WO1997026068A1 - Method and apparatus for continuous adsorption of adsorbable contaminates and adsorber - Google Patents

Method and apparatus for continuous adsorption of adsorbable contaminates and adsorber Download PDF

Info

Publication number
WO1997026068A1
WO1997026068A1 PCT/US1996/015659 US9615659W WO9726068A1 WO 1997026068 A1 WO1997026068 A1 WO 1997026068A1 US 9615659 W US9615659 W US 9615659W WO 9726068 A1 WO9726068 A1 WO 9726068A1
Authority
WO
WIPO (PCT)
Prior art keywords
adsorber
inlet
chamber
desorbent
regeneratable
Prior art date
Application number
PCT/US1996/015659
Other languages
French (fr)
Inventor
Jerald L. Mestemaker
Russel C. Wooten
B. R. Thakker
Paul E. Vargas
Andrew N. Andrascik
Randel W. Gulley
Richard F. Smith
Roderick O. Koehler
Timothy V. Johnson
David L. Hickman
Original Assignee
Calgon Carbon Corporation
Corning, Incorporated
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Calgon Carbon Corporation, Corning, Incorporated filed Critical Calgon Carbon Corporation
Publication of WO1997026068A1 publication Critical patent/WO1997026068A1/en

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D53/00Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/02Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography
    • B01D53/06Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols by adsorption, e.g. preparative gas chromatography with moving adsorbents, e.g. rotating beds
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J20/00Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
    • B01J20/02Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material
    • B01J20/20Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof comprising inorganic material comprising free carbon; comprising carbon obtained by carbonising processes
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J20/00Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
    • B01J20/28Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
    • B01J20/28014Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their form
    • B01J20/28042Shaped bodies; Monolithic structures
    • B01J20/28045Honeycomb or cellular structures; Solid foams or sponges
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J20/00Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
    • B01J20/30Processes for preparing, regenerating, or reactivating
    • B01J20/34Regenerating or reactivating
    • B01J20/3416Regenerating or reactivating of sorbents or filter aids comprising free carbon, e.g. activated carbon
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01JCHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J20/00Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
    • B01J20/30Processes for preparing, regenerating, or reactivating
    • B01J20/34Regenerating or reactivating
    • B01J20/3483Regenerating or reactivating by thermal treatment not covered by groups B01J20/3441 - B01J20/3475, e.g. by heating or cooling
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2253/00Adsorbents used in seperation treatment of gases and vapours
    • B01D2253/10Inorganic adsorbents
    • B01D2253/102Carbon
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2253/00Adsorbents used in seperation treatment of gases and vapours
    • B01D2253/10Inorganic adsorbents
    • B01D2253/106Silica or silicates
    • B01D2253/108Zeolites
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2253/00Adsorbents used in seperation treatment of gases and vapours
    • B01D2253/30Physical properties of adsorbents
    • B01D2253/34Specific shapes
    • B01D2253/342Monoliths
    • B01D2253/3425Honeycomb shape
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2257/00Components to be removed
    • B01D2257/10Single element gases other than halogens
    • B01D2257/11Noble gases
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2257/00Components to be removed
    • B01D2257/70Organic compounds not provided for in groups B01D2257/00 - B01D2257/602
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2257/00Components to be removed
    • B01D2257/70Organic compounds not provided for in groups B01D2257/00 - B01D2257/602
    • B01D2257/704Solvents not covered by groups B01D2257/702 - B01D2257/7027
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2257/00Components to be removed
    • B01D2257/70Organic compounds not provided for in groups B01D2257/00 - B01D2257/602
    • B01D2257/708Volatile organic compounds V.O.C.'s
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2259/00Type of treatment
    • B01D2259/40Further details for adsorption processes and devices
    • B01D2259/40083Regeneration of adsorbents in processes other than pressure or temperature swing adsorption
    • B01D2259/40088Regeneration of adsorbents in processes other than pressure or temperature swing adsorption by heating
    • B01D2259/4009Regeneration of adsorbents in processes other than pressure or temperature swing adsorption by heating using hot gas
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2259/00Type of treatment
    • B01D2259/40Further details for adsorption processes and devices
    • B01D2259/40083Regeneration of adsorbents in processes other than pressure or temperature swing adsorption
    • B01D2259/40088Regeneration of adsorbents in processes other than pressure or temperature swing adsorption by heating
    • B01D2259/40096Regeneration of adsorbents in processes other than pressure or temperature swing adsorption by heating by using electrical resistance heating
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D2259/00Type of treatment
    • B01D2259/45Gas separation or purification devices adapted for specific applications
    • B01D2259/4541Gas separation or purification devices adapted for specific applications for portable use, e.g. gas masks

Definitions

  • the present invention relates to a method and an apparatus for the removal of adsorbable contaminants from contaminant- laden fluid streams and more particularly to a method and an apparatus for the continuous removal of VOCs from a point source thereof and for the continuous regeneration of the adsorbent used in their removal.
  • VOC volatile organic compounds
  • the present invention comprises an adsorber and method for removing volatile materials from fluid streams containing the same.
  • the adsorber comprises an adsorber housing having a fluid stream inlet which can be connected, for example, to a source of gas containing contaminates to be removed prior to discharge to the atmosphere.
  • the adsorber housing also includes a fluid stream outlet which is connected to exhaust means for discharge to the atmosphere.
  • the adsorber housing also includes a plurality of adsorbent chambers.
  • Each chamber includes an electrically conductive adsorbent and at least one set of electrical connectors in contact with the adsorbent for selective connection with a source of electrical energy to provide resistive heating within the adsorbent.
  • each chamber is the form of one or more removable cassettes which contain the conductive adsorbent.
  • the cassettes include integrated electrical connectors which facilitate removal of individual cassettes in the event there is a need for replacement or repair of the adsorbent.
  • Each adsorbent chamber also includes a chamber fluid inlet and fluid outlet.
  • the chamber inlet is in communication with the adsorbent and in selective communication with the fluid stream inlet.
  • the chamber outlet is also in communication with the adsorbent and in communication with the gas stream outlet when both the fluid stream and chamber inlets are in communication with each other.
  • the housing includes a desorbent (regenerative) fluid inlet in selective communication with a chamber inlet and a source of desorbent fluid, normally nitrogen or other inert fluid.
  • a desorbent gas outlet is also provided in communication with said chamber outlet when the desorbent fluid inlet and chamber inlet are in commumcation with each other.
  • the desorbent fluid outlet is also in communication with a desorbent fluid exhaust means, typically a solvent regeneration, condensation or thermal oxidizing system.
  • the adsorber of the present invention also includes electrical control means for electrically connecting a source of electrical energy to at least one of the chambers to undergo regeneration. Electrical connection is made at least at the time desorbent fluid inlet and chamber inlet are in commumcation. Additionally, a desorbent fluid control means is provided for controlling the flow of desorbent through said desorbent inlet when it is in commumcation with the chamber inlet of an absorbent undergoing regeneration.
  • the adsorbent chambers are arranged in a rotatable wheel configuration.
  • one or multiple wheels may be employed depending upon the amount and nature of the fluid stream to be cleaned. These wheels may be arranged in parallel or, preferably, series to enhance removal of contaminates in a small sized system.
  • An important feature of the wheel configuration of the preferred embodiment is that at least one and preferably a majority of the chambers is rotated into alignment with the fluid inlet stream to remove contaminates therefrom. Simultaneously therewith, at least one of the chambers which has been exposed to the contaminated stream and saturated or substantially saturated with adsorbed solvents or organics is indexed with desorbent inlet to undergo regeneration. By utilizing a multiplicity of chambers, the adsorption/desorption process is substantially continuous.
  • the presently preferred embodiments of the invention utilize electrically heatable adsorbents extruded in the form of a monolithic honeycomb. These adsorbents are mounted within a removable cassette to provide an adsorbent having very efficient capacities which can be regenerated extremely fast.
  • the presently preferred embodiment of the invention provides for the continuous removal of VOCs in a package that is very cost effective and efficient.
  • Other advantages of the present invention will be apparent from a perusal of the following detailed description of the presently preferred embodiment taken in connection with the
  • Figure la is a diagrammatic view of the apparatus and method of the present invention employing a thermal oxidizer
  • Figure lb is a diagrammatic view of the invention employing solvent recovery means
  • Figure 2a is a sectional elevation of a preferred embodiment of a rotary wheel indexing configuration of the adsorbent chambers
  • Figure 2b is a sectional elevation of another embodiment of a rotary wheel adsorbent chamber
  • Figure 3 is a side elevation of the embodiment shown in Fig 2a;
  • Figure 4 is a side elevation of the chamber cassette of Figure 2a showing the preferred electrical connectors
  • Figure 5 is a sectional elevation taken along line V-V of Figure 4.
  • Figures 6 is a graphical profile of the temperature rise and cool down of the adsorbent and adsorbent chambers of the present invention.
  • Adsorber 10 comprises adsorber housing 11 having a gas stream inlet 12 and gas stream outlet 13.
  • Gas stream inlet 12 is adapted to connect to a source of solvent laden air or a gas stream contaimng VOCs.
  • the inlets and chambers can be designed to accommodate fluids other than gas. Because the efficiency of adsorber 10 is extremely high, it can be dimensioned to a relatively small, portable size. The small size allows the device to be either permanently or temporarily connected to a point source generator of gases to be treated. In its temporary configuration, adsorber 10 can be mounted on skids 43 (Fig 2a) to facilitate moving from point to point.
  • Adsorber housing 11 also includes a plurality of adsorbent chambers 14.
  • Each chamber 15 includes an electrically heatable adsorbent 16 (Fig. 2) and electrical connectors 18 and 19 for applying a current across the adsorbent.
  • the adsorbent is a monolithic extruded activated adsorbent such as those prepared and described in U.S. Patent No. [S.N. 08/249,897].
  • each chamber 15 be in the form of a removable cassette as described below.
  • the preferred monolithic or unitary structure comprises an activated carbon coated nonconductive inorganic substrate or unitary structure shaped entirely of activated carbon.
  • the substrate can be made from any nonelectrically conducting inorganic material so long as it has pores extending from its outer surface and is capable of withstanding the heat-treating temperatures used in forming the activated carbon coating. It is desirable that the overall open porosity of the substrate be at least about 10%; however, an open porosity between 40 and 50% is most desirable.
  • the pores of the substrate material create "interconnecting porosity" which is characterized by pores which connect into and/or intersect other pores to create a labyrinth network of porosity within the substrate.
  • Suitable porous substrate materials include ceramic, glass, and physical or chemical combinations thereof, e.g., mixtures, compounds, or composites. Some materials that are especially suitable such as those made of cordierite, mullite. clay, talc, zircon, zirconia, zirconates, zirconia-spinel, magnesium aluminosilicates, spinel, alumina, silica, silicates, borides, alumino-silicates, such as, porcelains, lithium aluminosilicates, alumina silica, feldspar, titania, fused silica, nitrides, borides, carbides, such as. silicon carbide, silicon nitride, or mixtures thereof.
  • Cordierite is preferred because its coefficient of thermal expansion is comparable to that of carbon, increasing the stability of the activated carbon body.
  • Some typical ceramic substrates are disclosed in U.S. Patents 4,127,691 and 3,885,977. These patents are herein inco ⁇ orated by reference.
  • the substrate preferably is a honeycomb but can take any known form including tubes, foams, or multicellular bodies; and typically, the substrate has open-ended channels for passage of a gas stream in and out of the body.
  • the substrate comprises a matrix of thin walls which form a multiplicity of open-ended cells extending between its ends.
  • honeycombs that are useful are those having about 172 cells/cm 2 (1100 cells/in 2 ), about 94 cells/cm 2 (600 cells/in 2 ), about 62 cells/cm 2 (400 cells/ in 2 ), or about 47 cells/cm 2 (300 cells/in 2 ), those having about 31 cells/cm 2 (200 cells/in 2 ), or about 15 cells/cm 2 (100 cells/in 2 ), or about 2.5 cells/cm 2 , (16 cells/in 2 ) or about 1.5 cells/cm 2 (9 cells/in 2 ).
  • Wall (web) thicknesses range typically from about 0.1 to about 1.3 mm (about 4 to about 50 mils). Other combinations of cell densities and wall thicknesses can be used.
  • cordierite honeycombs are especially preferred as substrates for the activated carbon.
  • a carbon coating is applied by contacting the substrate with a liquid carbon precursor (a carbon containing material which converts to a continuous carbon upon heating) which is cured and carbonized, and thereafter activated.
  • the carbon precursor is preferably liquified to penetrate into the interconnecting pores of the substrate so that upon curing and carbonizing, a coating is produced that is physically interlocked within the interconnecting pores of the substrate.
  • Carbon precursors useful in the present invention include any liquid or liquefiable, soluble or dispersible carbonaceous substance such as thermoplastic resins (e.g. , polyvinylidene chloride, polyvinyl chloride, polyvinyl alcohol, and the like), sugar solutions, furfuryl alcohol, and coal tar pitch.
  • thermoplastic resins e.g. , polyvinylidene chloride, polyvinyl chloride, polyvinyl alcohol, and the like
  • sugar solutions e.g. , furfuryl alcohol, and coal tar pitch.
  • Low viscosity carbon precursors e.g. , thermoset resins
  • Phenolic resins are most desirable because of their low viscosity, high carbon yield, high degree of cross-linking upon curing relative to other precursors, and low cost.
  • the carbon precursor liquid used in the present method can include a single precursor material or a mixture of two or more precursor materials.
  • activated carbon can be added to the carbon precursor liquid to increase the ads
  • the amount of carbon precursor retained by the substrate can be increased, e.g. , by contacting the substrate with the precursor more than once and allowing the substrate to dry between contacting steps.
  • the amount of precursor retained by the substrate can be controlled in porous substrates by simply modifying the overall porosity of the substrate (e.g., increasing porosity will increase the amount of precursor retained by the substrate and in turn the amount of carbon formed thereon).
  • the substrate and carbon precursor are then subjected to heat-treatments to cure the precursor and thereafter convert the precursor to continuous carbon (carbonize).
  • the resulting carbon-coated substrate is then heat-treated to activate the carbon and produce an
  • Curing is accomplished typically by heating the coated substrate to temperatures of about 100°C to about 200°C for about 0.5 to about 5.0 hours. Curing is generally performed in air at atmospheric pressures. When using certain precursors (e.g., furfuryl alcohol), curing can be accomplished by adding an acid catalyst at room temperature.
  • precursors e.g., furfuryl alcohol
  • Carbonization comprises the thermal decomposition of the carbonaceous material which eliminates low molecular weight species (e.g. , carbon dioxide, water, etc.) and produces a fixed carbon mass and a rudimentary pore structure in the carbon.
  • low molecular weight species e.g. , carbon dioxide, water, etc.
  • Such conversion or carbonization of the cured carbon precursor is accomplished typically by heating the substrate to a temperature in the range of about 600 °C to about 1000°C for about 1 to 10 hours in a reducing or inert atmosphere (e.g., nitrogen, argon, etc.).
  • Curing and carbonizing the carbon precursor on the substrate results in a structure having a coating extending over the entire surface of the substrate in the form of a substantially uninterrupted layer of carbon.
  • This carbon coating is anchored into the porosity of the substrate and as a result is highly adherent.
  • the top surface of the carbon coating is an uninterrupted layer of carbon to carbon bonds.
  • Activation of the carbon layer to increase the size of the micro pores as well as increase the number of pores by well known methods. For example, exposing the structure to steam or carbon dioxide at high temperatures, e.g., 600-1000° C or above is suitable.
  • the plurality of chambers 14 are configured in the form of a rotatable indexing wheel 17 as shown in Figure 2a and 2b.
  • the number of chambers 15 depends upon the size and capacity of the adsorber desired as well as whether more than one adsorber wheel is to be used.
  • Adsorber wheels 17 may be arranged in series or parallel to achieve the maximum desired benefit of removal and regeneration.
  • Adsorber housing 11 also includes a desorber gas inlet 21 and a desorber gas outlet 22 which are adapted to selectively commumcate with at least one chamber inlet 51 and chamber outlet 52, respectively, through the adsorber.
  • Desorber gas inlet 21 and desorber gas outlet 22 are connected with a source of desorber gas 24 and exhaust 26, respectively.
  • Desorber gas outlet 22 is aligned for communication with chamber outlet 52 when desorber gas inlet 21 is in commumcation with chamber inlet for desorbing adsorbent 16.
  • Electrodes 18 and 19 of chamber 15 are electrically connected to a source of electrical energy 36 by means of connectors 31 and 32 are engagedly mounted on desorber gas inlet 21 and wires 37 and 38 respectively. (See Fig 4 and Fig 5).
  • Control connectors 31 and 32 provide electrical current to adsorbent 16 in a chamber 15 by electrodes 18 and 19 through electrical connectors 33 and 34, respectively. Electrical contact with source 36 is made when a chamber is connected for commumcation with a desorbent gas during the chamber's regeneration cycle.
  • a flow of desorbent gas through the electrically heated adsorbent desorbs from the adsorbent adsorbed volatile compounds and exhausts them through desorbent gas outlet 22.
  • the desorbent gas acts as a carrier of the volatiles to a thermal oxidizer 41 to oxidize the organics prior to discharge to the atmosphere.
  • organics or solvents can be recovered using a conventional condenser and decanter for stripping the solvent from a water phase, for example, as diagrammatically shown in Fig lb.
  • chamber 15 is first purged of any oxygen by passing a small amount of inert gas preferably nitrogen from a nitrogen generator 24.
  • absorbent 16 After purging, electrical energy is preferably applied to the absorbent 16 to cause absorbent 16 to reach a temperature between about 100°C and 250°C.
  • FIG 6 the time to heat adsorbent 16 to 200°C is shown.
  • temperature profiles of a carbon honeycomb adsorbent and the areas between the carbon and the insulation 53 used in the walls of chamber 15 are shown. What is important is the fact that the temperature of the adsorbent reaches a temperature of about 200 °C within a very short time to provide rapid regeneration.
  • the desorbent gas does not have to be heated, thus eliminating costly and inefficient desorbent, fluid heating means.
  • the regeneration cycle time of each chamber 15 is about 2 to 4 minutes. As the absorbent reaches the desired regeneration temperature VOCs and other adsorbed contaminates are desorbed from the absorbent 16. A small amount of deso ⁇ tion gas is directed through the deso ⁇ tion gas inlet and through chamber 15 undergoing regeneration to purge the gases or vapors therefrom.
  • an inert deso ⁇ tion gas such as nitrogen.
  • air may be optionally used, but it is not desirable.
  • the amount of gas needed to purge the volatiles from the absorbent is small because the heat generated by the electrical resistance of the absorbent supplies the heat necessary to effectuate deso ⁇ tion.
  • the flow rate of the deso ⁇ tion gas is preferable such that the pa ⁇ ial pressure of the volatiles in the deso ⁇ tion gas is slightly lower than the equilibrium pressure of the volatiles on the absorbent.
  • the maximum volatile concentration in the desorbent gas can be up to 50 vol % (500,000 ppmw) or higher.
  • FIG. 2a two embodiments of multiple chambers 15 are configured as an indexable wheel 7.
  • FIG. 2a six chambers 15a-f are positioned on the periphery of wheel housing 42 which preferably comprises part of adsorber housing 11.
  • Wheel housing 42 is rotatably mounted on skid frame 43 by a plurality of support wheels 44.
  • a hydraulic cylinder 47 mounted to skid frame 43 includes a hydraulic pump 48 used to activate indexable rotation wheel housing 42.
  • the wheel housing can be indexed by an electrically operated screw-linear activator.
  • wheel housing can include gear means into which a motor and transmission gear can engage to provide continuous or indexable rotation.
  • deso ⁇ tion gas inlet 21 is in commumcation with chamber inlet 51a of chamber 15a and desorber gas outlet 22 is in communication with chamber outlet 52a.
  • a seal made of stainless steel and teflon is provided around the periphery of deso ⁇ tion gas inlet 21 and abso ⁇ tion gas outlet 22 to seal the regeneration loop from the adso ⁇ tion loop.
  • chambers 15b-f are in communication with gas stream inlet 12 and gas stream outlet 13. At such time, chambers 15b is most nearly saturated with solvent and chamber 15f with the least having been most recently regenerated when wheel 17 is rotated in a counter-clockwise direction pe ⁇ endicular to the flow of gas.
  • an adsorbent shown in Figure 2a is shown in more detail.
  • a plurality of electrodes 18 and 19 are shown connected to connectors 31 and 32. It is important that the electrical contacts be configured to provide a uniform electrical distribution through the adsorbent so as not to create localized hot spots.
  • the conducting means must provide a resistivity of at least about 0.001 ohm.cm, but typically at least about 0.01 ohms, and most typically at least about 0.10
  • the resistivity is between about 0.10 ohm.cm and 25 ohm.cm.
  • the voltage and current requirement will vary depending on the application, and the resistivity can be adjusted as desired. For example, if the body is to be heated in an oxygen containing atmosphere, the voltage and current should be such as to raise the temperature so that no spot in the body is higher than about 350°C. If the body is to be heated in an inert or non-reacting atmosphere, e.g., N 2 , the voltage and current should be such as to raise the temperature so that no spot in the body is higher than about 1000°C.
  • Some especially preferred conducting materials are metals such as copper, silver, aluminum, zinc, nickel, lead, tin and their alloys, with the preferred being copper because of its high conductivity which minimizes resistance and is inexpensive.
  • the conducting means is typically either in the form of a strip of conducting material, electrode or a coating of conductive material on the monolithic structure.
  • an electrode it can be applied by pressure contact, e.g., a spring.
  • a strip of conducting metal 18 or 19 can also be used and can be attached to the structure by an electrically conducting adhesive such as conductive adhesive #3021 from Acme Chemicals and Insulation Co.
  • One especially preferred geometry is placing the conducting metal applied to opposing surfaces of the monolithic body.
  • opposing surfaces is meant surfaces that are so spaced according to the geometry of the body that passage of a current between the conductive surfaces produces a current that heats the carbon uniformly.
  • FIG. 2b another embodiment of the rotatable wheel configuration is shown in which multiple chambers 14 include additional chamber capacities 15(i).
  • deso ⁇ tion gas inlet 21 is configured in the shape of a "V" to access the additional chamber capacity 15(i).
  • electrical connectors 31a and 32a on chamber 15a connect with electrical connectors 33 and 34 mounted on inlet 21.
  • the temperature in the cells of adsorbent 16 quickly rises to the desired operating temperature.
  • chamber 15b Upon completion of the regeneration of chamber 15a, chamber 15b would be indexed for regeneration, and so on with the chamber being regenerated sequentially.
  • Nitrogen consumption 1.68 SCF per cycle Nitrogen Rate 5.0 SCFM

Abstract

A regeneratable adsorber (10) for adsorbing adsorbable contaminates from a fluid stream containing same is disclosed. The adsorber includes an adsorber housing (11) in which there is a fluid stream inlet (12) and a fluid stream outlet (13). The adsorber also includes a plurality of adsorber chambers (15) which are arranged in an indexable wheel configuration. Each chamber includes an electrically conductive adsorbent, such as a monolithic activated carbon, a set of electrical conductors (18, 19) in contact with the adsorbent, and an inlet (51) and outlet (52). A chamber is either in contact with a source of contaminate fluid or a desorbent fluid used to regenerate the adsorber. The adsorber includes control means for selectively indexing chambers for adsorption or desorption to provide continuous contaminate adsorption and regeneration.

Description

METHOD AND APPARATUS FOR CONTINUOUS ADSORBTION OF ADSORBABLE CONTAMINATES AND ADSORBER.
FIELD OF THE INVENTION
The present invention relates to a method and an apparatus for the removal of adsorbable contaminants from contaminant- laden fluid streams and more particularly to a method and an apparatus for the continuous removal of VOCs from a point source thereof and for the continuous regeneration of the adsorbent used in their removal.
BACKGROUND OF THE INVENTION
Methods and apparatus for the removal of adsorbable contaminants, in particular, volatile organic compounds ("VOC") from air streams are very well known. Typical of such systems is the use of activated carbon for the removal of VOCs and the use of a heated regeneration gas for desorbing the adsorbed VOCs from the adsorbent. To provide a substantially continuous removal process, at least two adsorber vessels are used in which one adsorber is adsorbing the VOCs from the gas stream while the other adsorber is being regenerated for use. In some cases more than two vessels are used to enhance the continuity of the system's performance.
The apparatus and methods of the prior art that are used for VOC removal from the commercial gas stream provide satisfactory removal rates. However, these processes require the use of large stationary systems with high flow rates of hot desorption (regenerative) gases. Many require the use of external combustion means to heat the desorption gases to facilitate the desorption process, often with inefficient thermal transfer to the adsorbent. These systems also require large processing equipment to handle the large flow of gases to recover or oxidize the solvents/VOCs removed from the adsorbent.
Accordingly, it is an object of the present invention to provide a method and apparatus for the efficient removal of VOCs, other organic contaminates and adsorbable materials from fluid streams using reduced desorbent fluid flows. It is a further object of the invention to provide apparatus for the removal of contaminates which can be made portable and capable of being attached to point sources of contaminate generation. It is yet a further object of the invention to provide an apparatus which is capable of continuous adsorption and removal of VOCs and other adsorbable contaminates with substantially simultaneous regeneration of the adsorbent using reduced flows of desorbent fluids without external heating means to achieve high thermal desorption efficiency.
SUMMARY OF THE INVENTION
The present invention comprises an adsorber and method for removing volatile materials from fluid streams containing the same. Generally, the adsorber comprises an adsorber housing having a fluid stream inlet which can be connected, for example, to a source of gas containing contaminates to be removed prior to discharge to the atmosphere. The adsorber housing also includes a fluid stream outlet which is connected to exhaust means for discharge to the atmosphere.
The adsorber housing also includes a plurality of adsorbent chambers. Each chamber includes an electrically conductive adsorbent and at least one set of electrical connectors in contact with the adsorbent for selective connection with a source of electrical energy to provide resistive heating within the adsorbent. Preferably, each chamber is the form of one or more removable cassettes which contain the conductive adsorbent. Preferably, the cassettes include integrated electrical connectors which facilitate removal of individual cassettes in the event there is a need for replacement or repair of the adsorbent.
Each adsorbent chamber also includes a chamber fluid inlet and fluid outlet. The chamber inlet is in communication with the adsorbent and in selective communication with the fluid stream inlet. The chamber outlet is also in communication with the adsorbent and in communication with the gas stream outlet when both the fluid stream and chamber inlets are in communication with each other.
The housing includes a desorbent (regenerative) fluid inlet in selective communication with a chamber inlet and a source of desorbent fluid, normally nitrogen or other inert fluid. A desorbent gas outlet is also provided in communication with said chamber outlet when the desorbent fluid inlet and chamber inlet are in commumcation with each other. The desorbent fluid outlet is also in communication with a desorbent fluid exhaust means, typically a solvent regeneration, condensation or thermal oxidizing system.
The adsorber of the present invention also includes electrical control means for electrically connecting a source of electrical energy to at least one of the chambers to undergo regeneration. Electrical connection is made at least at the time desorbent fluid inlet and chamber inlet are in commumcation. Additionally, a desorbent fluid control means is provided for controlling the flow of desorbent through said desorbent inlet when it is in commumcation with the chamber inlet of an absorbent undergoing regeneration.
In a presently preferred embodiment of the invention, the adsorbent chambers are arranged in a rotatable wheel configuration. In the preferred embodiment, one or multiple wheels may be employed depending upon the amount and nature of the fluid stream to be cleaned. These wheels may be arranged in parallel or, preferably, series to enhance removal of contaminates in a small sized system. An important feature of the wheel configuration of the preferred embodiment is that at least one and preferably a majority of the chambers is rotated into alignment with the fluid inlet stream to remove contaminates therefrom. Simultaneously therewith, at least one of the chambers which has been exposed to the contaminated stream and saturated or substantially saturated with adsorbed solvents or organics is indexed with desorbent inlet to undergo regeneration. By utilizing a multiplicity of chambers, the adsorption/desorption process is substantially continuous.
During the desoφtion process or immediately before commencement of the desoφtion process, electrical energy is directed into the chamber(s) that is to be regenerated. By impressing a current through the electrically resistive heating adsorbent, the adsorbent's temperature is increased to facilitate desoφtion of the adsorbed volatiles in the presence of a desoφtion fluid such as nitrogen. In the preferred embodiment of the invention, the temperature of the adsorbent is quickly raised to between about 155°C and 200° C. Electrically heatable adsorbents are disclosed and described in U.S. Patent No. [S.N. 08/249,897 filed 5/26/94] which is incoφorated herein by reference. The presently preferred embodiments of the invention utilize electrically heatable adsorbents extruded in the form of a monolithic honeycomb. These adsorbents are mounted within a removable cassette to provide an adsorbent having very efficient capacities which can be regenerated extremely fast.
The presently preferred embodiment of the invention provides for the continuous removal of VOCs in a package that is very cost effective and efficient. Other advantages of the present invention will be apparent from a perusal of the following detailed description of the presently preferred embodiment taken in connection with the
accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure la is a diagrammatic view of the apparatus and method of the present invention employing a thermal oxidizer;
Figure lb is a diagrammatic view of the invention employing solvent recovery means;
Figure 2a is a sectional elevation of a preferred embodiment of a rotary wheel indexing configuration of the adsorbent chambers;
Figure 2b is a sectional elevation of another embodiment of a rotary wheel adsorbent chamber;
Figure 3 is a side elevation of the embodiment shown in Fig 2a;
Figure 4 is a side elevation of the chamber cassette of Figure 2a showing the preferred electrical connectors;
Figure 5 is a sectional elevation taken along line V-V of Figure 4;
Figures 6 is a graphical profile of the temperature rise and cool down of the adsorbent and adsorbent chambers of the present invention.
PRESENTLY PREFERRED EMBODIMENT
Referring to Figure la, a presently preferred embodiment of the regeneratable adsorber 10 of the invention for use in the removal of VOCs from gas streams is shown. Adsorber 10 comprises adsorber housing 11 having a gas stream inlet 12 and gas stream outlet 13. Gas stream inlet 12 is adapted to connect to a source of solvent laden air or a gas stream contaimng VOCs. However, as is known to those skilled in the art, the inlets and chambers can be designed to accommodate fluids other than gas. Because the efficiency of adsorber 10 is extremely high, it can be dimensioned to a relatively small, portable size. The small size allows the device to be either permanently or temporarily connected to a point source generator of gases to be treated. In its temporary configuration, adsorber 10 can be mounted on skids 43 (Fig 2a) to facilitate moving from point to point.
Adsorber housing 11 also includes a plurality of adsorbent chambers 14. Each chamber 15 includes an electrically heatable adsorbent 16 (Fig. 2) and electrical connectors 18 and 19 for applying a current across the adsorbent. Preferably, the adsorbent is a monolithic extruded activated adsorbent such as those prepared and described in U.S. Patent No. [S.N. 08/249,897]. When a monolithic adsorber 16 is used, it is preferred that each chamber 15 be in the form of a removable cassette as described below. The preferred monolithic or unitary structure comprises an activated carbon coated nonconductive inorganic substrate or unitary structure shaped entirely of activated carbon. The substrate can be made from any nonelectrically conducting inorganic material so long as it has pores extending from its outer surface and is capable of withstanding the heat-treating temperatures used in forming the activated carbon coating. It is desirable that the overall open porosity of the substrate be at least about 10%; however, an open porosity between 40 and 50% is most desirable. Preferably, the pores of the substrate material create "interconnecting porosity" which is characterized by pores which connect into and/or intersect other pores to create a labyrinth network of porosity within the substrate.
Suitable porous substrate materials include ceramic, glass, and physical or chemical combinations thereof, e.g., mixtures, compounds, or composites. Some materials that are especially suitable such as those made of cordierite, mullite. clay, talc, zircon, zirconia, zirconates, zirconia-spinel, magnesium aluminosilicates, spinel, alumina, silica, silicates, borides, alumino-silicates, such as, porcelains, lithium aluminosilicates, alumina silica, feldspar, titania, fused silica, nitrides, borides, carbides, such as. silicon carbide, silicon nitride, or mixtures thereof. Cordierite is preferred because its coefficient of thermal expansion is comparable to that of carbon, increasing the stability of the activated carbon body. Some typical ceramic substrates are disclosed in U.S. Patents 4,127,691 and 3,885,977. These patents are herein incoφorated by reference.
The substrate preferably is a honeycomb but can take any known form including tubes, foams, or multicellular bodies; and typically, the substrate has open-ended channels for passage of a gas stream in and out of the body. In the preferred form the substrate comprises a matrix of thin walls which form a multiplicity of open-ended cells extending between its ends. Some examples of honeycombs that are useful are those having about 172 cells/cm2 (1100 cells/in2), about 94 cells/cm2 (600 cells/in2), about 62 cells/cm2 (400 cells/ in2), or about 47 cells/cm2 (300 cells/in2), those having about 31 cells/cm2 (200 cells/in2), or about 15 cells/cm2 (100 cells/in2), or about 2.5 cells/cm2, (16 cells/in2) or about 1.5 cells/cm2 (9 cells/in2). Wall (web) thicknesses range typically from about 0.1 to about 1.3 mm (about 4 to about 50 mils). Other combinations of cell densities and wall thicknesses can be used.
For puφoses of the present invention, cordierite honeycombs are especially preferred as substrates for the activated carbon. Preferably, a carbon coating is applied by contacting the substrate with a liquid carbon precursor (a carbon containing material which converts to a continuous carbon upon heating) which is cured and carbonized, and thereafter activated. The carbon precursor is preferably liquified to penetrate into the interconnecting pores of the substrate so that upon curing and carbonizing, a coating is produced that is physically interlocked within the interconnecting pores of the substrate. One preferred body of this type is described in U.S. patent application [S.N. 08/011,385, filed 1/29/93] and is incoφorated by reference herein as filed.
Carbon precursors useful in the present invention include any liquid or liquefiable, soluble or dispersible carbonaceous substance such as thermoplastic resins (e.g. , polyvinylidene chloride, polyvinyl chloride, polyvinyl alcohol, and the like), sugar solutions, furfuryl alcohol, and coal tar pitch. Low viscosity carbon precursors (e.g. , thermoset resins) are preferred because their lower viscosity allows greater penetration of the carbon precursor into porous inorganic substrates. Phenolic resins are most desirable because of their low viscosity, high carbon yield, high degree of cross-linking upon curing relative to other precursors, and low cost. The carbon precursor liquid used in the present method can include a single precursor material or a mixture of two or more precursor materials. Optionally, activated carbon can be added to the carbon precursor liquid to increase the adsoφtive capability of the activated carbon structure.
The amount of carbon precursor retained by the substrate can be increased, e.g. , by contacting the substrate with the precursor more than once and allowing the substrate to dry between contacting steps. In addition, the amount of precursor retained by the substrate can be controlled in porous substrates by simply modifying the overall porosity of the substrate (e.g., increasing porosity will increase the amount of precursor retained by the substrate and in turn the amount of carbon formed thereon).
The substrate and carbon precursor are then subjected to heat-treatments to cure the precursor and thereafter convert the precursor to continuous carbon (carbonize). The resulting carbon-coated substrate is then heat-treated to activate the carbon and produce an
activated carbon structure.
Curing is accomplished typically by heating the coated substrate to temperatures of about 100°C to about 200°C for about 0.5 to about 5.0 hours. Curing is generally performed in air at atmospheric pressures. When using certain precursors (e.g., furfuryl alcohol), curing can be accomplished by adding an acid catalyst at room temperature.
Carbonization comprises the thermal decomposition of the carbonaceous material which eliminates low molecular weight species (e.g. , carbon dioxide, water, etc.) and produces a fixed carbon mass and a rudimentary pore structure in the carbon. Such conversion or carbonization of the cured carbon precursor is accomplished typically by heating the substrate to a temperature in the range of about 600 °C to about 1000°C for about 1 to 10 hours in a reducing or inert atmosphere (e.g., nitrogen, argon, etc.).
Curing and carbonizing the carbon precursor on the substrate results in a structure having a coating extending over the entire surface of the substrate in the form of a substantially uninterrupted layer of carbon. This carbon coating is anchored into the porosity of the substrate and as a result is highly adherent. The top surface of the carbon coating is an uninterrupted layer of carbon to carbon bonds.
Activation of the carbon layer to increase the size of the micro pores as well as increase the number of pores by well known methods. For example, exposing the structure to steam or carbon dioxide at high temperatures, e.g., 600-1000° C or above is suitable.
Preferably, the plurality of chambers 14 are configured in the form of a rotatable indexing wheel 17 as shown in Figure 2a and 2b. The number of chambers 15 depends upon the size and capacity of the adsorber desired as well as whether more than one adsorber wheel is to be used. Adsorber wheels 17 may be arranged in series or parallel to achieve the maximum desired benefit of removal and regeneration.
Adsorber housing 11 also includes a desorber gas inlet 21 and a desorber gas outlet 22 which are adapted to selectively commumcate with at least one chamber inlet 51 and chamber outlet 52, respectively, through the adsorber. Desorber gas inlet 21 and desorber gas outlet 22 are connected with a source of desorber gas 24 and exhaust 26, respectively. Desorber gas outlet 22 is aligned for communication with chamber outlet 52 when desorber gas inlet 21 is in commumcation with chamber inlet for desorbing adsorbent 16.
Electrodes 18 and 19 of chamber 15 are electrically connected to a source of electrical energy 36 by means of connectors 31 and 32 are engagedly mounted on desorber gas inlet 21 and wires 37 and 38 respectively. (See Fig 4 and Fig 5). Control connectors 31 and 32 provide electrical current to adsorbent 16 in a chamber 15 by electrodes 18 and 19 through electrical connectors 33 and 34, respectively. Electrical contact with source 36 is made when a chamber is connected for commumcation with a desorbent gas during the chamber's regeneration cycle.
A flow of desorbent gas through the electrically heated adsorbent desorbs from the adsorbent adsorbed volatile compounds and exhausts them through desorbent gas outlet 22. In a preferred embodiment, the desorbent gas acts as a carrier of the volatiles to a thermal oxidizer 41 to oxidize the organics prior to discharge to the atmosphere. Alternatively, organics or solvents can be recovered using a conventional condenser and decanter for stripping the solvent from a water phase, for example, as diagrammatically shown in Fig lb. In the process of regeneration, chamber 15 is first purged of any oxygen by passing a small amount of inert gas preferably nitrogen from a nitrogen generator 24. After purging, electrical energy is preferably applied to the absorbent 16 to cause absorbent 16 to reach a temperature between about 100°C and 250°C. Referring to Figure 6, the time to heat adsorbent 16 to 200°C is shown. In this illustration, temperature profiles of a carbon honeycomb adsorbent and the areas between the carbon and the insulation 53 used in the walls of chamber 15 are shown. What is important is the fact that the temperature of the adsorbent reaches a temperature of about 200 °C within a very short time to provide rapid regeneration. Moreover, because the heat is generated internally of chamber 15, the desorbent gas does not have to be heated, thus eliminating costly and inefficient desorbent, fluid heating means.
The regeneration cycle time of each chamber 15 is about 2 to 4 minutes. As the absorbent reaches the desired regeneration temperature VOCs and other adsorbed contaminates are desorbed from the absorbent 16. A small amount of desoφtion gas is directed through the desoφtion gas inlet and through chamber 15 undergoing regeneration to purge the gases or vapors therefrom.
In cases where flammable mixtures are to be desorbed, it is very desirable to utilize an inert desoφtion gas such as nitrogen. However, where the mixtures are not flammable, air may be optionally used, but it is not desirable. The amount of gas needed to purge the volatiles from the absorbent is small because the heat generated by the electrical resistance of the absorbent supplies the heat necessary to effectuate desoφtion. The flow rate of the desoφtion gas is preferable such that the paπial pressure of the volatiles in the desoφtion gas is slightly lower than the equilibrium pressure of the volatiles on the absorbent. The maximum volatile concentration in the desorbent gas can be up to 50 vol % (500,000 ppmw) or higher.
Referring to Figures 2a and 2b, two embodiments of multiple chambers 15 are configured as an indexable wheel 7. In figure 2a, six chambers 15a-f are positioned on the periphery of wheel housing 42 which preferably comprises part of adsorber housing 11. Wheel housing 42 is rotatably mounted on skid frame 43 by a plurality of support wheels 44.
A hydraulic cylinder 47 mounted to skid frame 43 includes a hydraulic pump 48 used to activate indexable rotation wheel housing 42. The wheel housing can be indexed by an electrically operated screw-linear activator. Alternatively, wheel housing can include gear means into which a motor and transmission gear can engage to provide continuous or indexable rotation.
Referring to Figure 2a and Figure 3, desoφtion gas inlet 21 is in commumcation with chamber inlet 51a of chamber 15a and desorber gas outlet 22 is in communication with chamber outlet 52a. Preferably, a seal made of stainless steel and teflon is provided around the periphery of desoφtion gas inlet 21 and absoφtion gas outlet 22 to seal the regeneration loop from the adsoφtion loop. During the period chamber 15a is undergoing regeneration, chambers 15b-f are in communication with gas stream inlet 12 and gas stream outlet 13. At such time, chambers 15b is most nearly saturated with solvent and chamber 15f with the least having been most recently regenerated when wheel 17 is rotated in a counter-clockwise direction peφendicular to the flow of gas.
Referring to Figures 4 and 5 , an adsorbent shown in Figure 2a is shown in more detail. In this embodiment, a plurality of electrodes 18 and 19 are shown connected to connectors 31 and 32. It is important that the electrical contacts be configured to provide a uniform electrical distribution through the adsorbent so as not to create localized hot spots. Generally, the conducting means must provide a resistivity of at least about 0.001 ohm.cm, but typically at least about 0.01 ohms, and most typically at least about 0.10
ohm. cm. For most puφoses of the present application, the resistivity is between about 0.10 ohm.cm and 25 ohm.cm.
The voltage and current requirement will vary depending on the application, and the resistivity can be adjusted as desired. For example, if the body is to be heated in an oxygen containing atmosphere, the voltage and current should be such as to raise the temperature so that no spot in the body is higher than about 350°C. If the body is to be heated in an inert or non-reacting atmosphere, e.g., N2, the voltage and current should be such as to raise the temperature so that no spot in the body is higher than about 1000°C.
Some especially preferred conducting materials are metals such as copper, silver, aluminum, zinc, nickel, lead, tin and their alloys, with the preferred being copper because of its high conductivity which minimizes resistance and is inexpensive.
The conducting means is typically either in the form of a strip of conducting material, electrode or a coating of conductive material on the monolithic structure.
If an electrode is used, it can be applied by pressure contact, e.g., a spring. A strip of conducting metal 18 or 19 can also be used and can be attached to the structure by an electrically conducting adhesive such as conductive adhesive #3021 from Acme Chemicals and Insulation Co.
On the other hand, it has been found that a conductive coating is cost effective and gives a uniform resistance path so as to avoid hot spots in this application.
One especially preferred geometry is placing the conducting metal applied to opposing surfaces of the monolithic body. By opposing surfaces is meant surfaces that are so spaced according to the geometry of the body that passage of a current between the conductive surfaces produces a current that heats the carbon uniformly.
With reference to Figure 2b, another embodiment of the rotatable wheel configuration is shown in which multiple chambers 14 include additional chamber capacities 15(i). In this embodiment, desoφtion gas inlet 21 is configured in the shape of a "V" to access the additional chamber capacity 15(i). When chamber 15a is indexed into a sealing engagement with desorbing gas inlet 21, electrical connectors 31a and 32a on chamber 15a connect with electrical connectors 33 and 34 mounted on inlet 21. As described above, upon positioning of chamber 15a in communication with the desoφtion gas, and the commencement of electrical energy, the temperature in the cells of adsorbent 16 quickly rises to the desired operating temperature. Upon completion of the regeneration of chamber 15a, chamber 15b would be indexed for regeneration, and so on with the chamber being regenerated sequentially.
Set forth below is an example of preferred operating parameters of a small adsorber 10 having a wheel 17 diameter of 48" used to remove toluene from a gas stream.
GAS STREAM
SLA Flow 4,000 SCFM
SLA Temperature 100 F
Solvent Type Toluene
Cone. 300 PPMW
Rate 5.4 Lbs. per hour
Removal efficiency 98%
WHEEL
Type Carbon Coated Ceramic Honeycomb
Cell Density 400 Cells/sq. in.
Bulk Density 0.39 Gms/ml
Adsorbent Sp. Heat 0.18 Btus/Lb/F
Size 48" Diameter Depth 4"
Adsorbent Volume 4.2 Cu. Ft.
Adsorbent Weight 102 Lbs.
Total Area 12.56 Sq. Ft.
Speed 3 Revolutions per hour
Time per Revolution 20 minutes
CYCLE TIMES
Adsoφtion 16 Minutes Regeneration 4 Minutes
Purge 20 Seconds
Desoφtion 180 Seconds
Cooling 40 Seconds
ADSORPTION
Zone 80% wheel
Flow Area 10.05 Sq. Ft.
SLA Velocity 420 FPM
Pressure Drop 0.61 W.C.
Solvent Adsorbed/rev. 1.8 Lbs.
Expected Working Capacity 8.6 Gms/litre 2.2 Wt
REGENERATION
Zone 20% wheel
PURGE
Nitrogen consumption 1.68 SCF per cycle Nitrogen Rate 5.0 SCFM
DESORPTION
Temperature 300°F Nitrogen Velocity 0.5 SFPM Nitrogen Flow 1.25 SCFM Solvent Desorbed 0.45 Lbs per cycle Heat Requirement 19,553 Btus/hr 5.56 KW While presently preferred embodiments of the invention have been shown in particularity the invention may be otherwise embodied within the scope of the appended claims.

Claims

WHAT IS CLAIMED IS:
1. A regeneratable adsorber for adsorbing adsorbable contaminates from a fluid stream containing same, said regeneratable adsorber comprising:
A. an adsorber housing having:
(i) a fluid stream inlet in commumcation with a source of such contaminated stream;
(ii) a fluid stream outlet connected to an exhaust means;
(iii) a plurality of adsorber chambers, each of said chambers including:
(a) an electrically conductive adsorbent,
(b) at least one set of electrical conductors in contact with said
adsorbent,
(c) a chamber inlet for communication with said fluid stream inlet, and
(d) a chamber outlet in communication with said adsorbent and for communication with said fluid stream outlet when said chamber inlet and fluid stream inlet are in communication;
(iv) a desorbent fluid inlet in selective communication with said chamber inlet and a source of desorbent fluid; and
(v) a desorbent fluid outlet in communication with a desorbent gas exhaust means and with said chamber outlet when said desorbent fluid inlet and chamber inlet are in communication;
B. means for selectively positioning at least one of said adsorber chamber inlets in communication with said fluid stream inlet; C . control means for electrically connecting at least one of said adsorber housing chambers to a source of electrical energy; and
D. desorbent fluid control means for selectively controlling the flow of desorbent fluid from a source thereof through a desorber inlet in communication with a chamber inlet.
2. A regeneratable adsorber as set forth in Claim 1 wherein said adsorber chambers are arranged in at least one wheel configuration.
3. A regeneratable adsorber as set forth in Claim 1 wherein said adsorber chambers are arranged in a plurality of wheel configuration.
4. A regeneratable adsorber as set forth in Claim 3 wherein said adsorber chambers comprise at least two wheels in series.
5. A regeneratable adsorber as set forth in Claim 1 wherein said fluid is selected from one of air, gas and vapor.
6. A regeneratable adsorber as set forth in Claim 5 wherein said adsorbable contaminate is selected from the group consisting of a volatile organic compound, hydrocarbon based solvents and radon.
7. A regeneratable adsorber as set forth in Claim 1, 2, 3, 4, 5, or 6 wherein said electrically conductive adsorber comprises a monolithic carbon structure having interconnecting pores for fluid passage.
8. A regeneratable adsorber as set forth in Claim 6 wherein said monolithic carbon is
in the form of a honeycomb.
9. A regeneratable adsorber as set forth in Claims 1, 2, 3, 4, 5 or 6 wherein said conductive adsorber is a monolithic structure selected from activated carbon and zeolite.
10. a regeneratable adsorber as set forth in Claims 1, 2, 3, 4, 5 or 6 wherein said conductive adsorbent comprises a monolithic activated carbon structure.
11. A regeneratable adsorber for removing volatile organic compounds from a gas stream containing same, said adsorber comprising:
A. a housing having:
(i) a gas stream inlet in communication with a gas stream containing volatile organic compounds;
(ii) a gas stream outlet means;
(iii) a plurality of adsorber chambers rotatable into and out of communication with said inlet and outlet, each chamber including:
(a) an electrically conductive monolithic adsorbent,
(b) a set of electrodes electrically connected to said adsorbent,
(c) a chamber inlet for commumcation with said gas stream inlet, and
(d) a chamber outlet for communication with said gas stream outlet means;
(iv) a desorbent gas inlet in selective communication with said chamber inlet and a source of desorbent gas;
(v) a desorbent gas outlet in commumcation with a desorbent exhaust means and with said chamber outlet when said desorbent gas inlet and chamber inlet are in communication; C. means for rotative said adsorber chamber;
D. control means for electrically connecting at least one adsorber chamber to a source of energy; and
E. desorbent gas control means.
12. A regeneratable adsorber as set forth in Claim 11 wherein said adsorbent is a monolithic activated carbon
13. A regeneratable adsorber as set forth in Claim 12 wherein said monolith is in the form of a honeycomb.
14. A regeneratable adsorber as set forth in Claim 11, 12, or 13 wherein said desorbent gas exhaust means includes a thermal oxidizer.
15. A regeneratable adsorber as set forth in Claim 11 , 12, or 13 wherein said desorbent exhaust means includes at least a condenser cooler and decanter.
PCT/US1996/015659 1995-09-28 1996-09-30 Method and apparatus for continuous adsorption of adsorbable contaminates and adsorber WO1997026068A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US08/534,931 US5628819A (en) 1995-09-28 1995-09-28 Method and apparatus for continuous adsorption of adsorbable contaminates and adsorber regeneration
US08/534,931 1995-09-28

Publications (1)

Publication Number Publication Date
WO1997026068A1 true WO1997026068A1 (en) 1997-07-24

Family

ID=24132123

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US1996/015659 WO1997026068A1 (en) 1995-09-28 1996-09-30 Method and apparatus for continuous adsorption of adsorbable contaminates and adsorber

Country Status (3)

Country Link
US (1) US5628819A (en)
TW (1) TW313530B (en)
WO (1) WO1997026068A1 (en)

Families Citing this family (37)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2738501B1 (en) * 1995-09-07 1997-10-17 Inst Francais Du Petrole PROCESS AND DEVICE FOR PURIFYING VASES OF GASEOUS EFFLUENTS LOADED WITH POLLUTANT SUBSTANCES
US5912423A (en) * 1997-01-23 1999-06-15 Calgon Carbon Corporation Method and means for purifying air with a regenerable carbon cloth sorbent
US5925323A (en) * 1997-05-12 1999-07-20 Durr Environmental, Inc. Concentration averaging device for impurities in industrial air stream
US6121179A (en) * 1998-01-08 2000-09-19 Chematur Engineering Ab Supercritical treatment of adsorbent materials
US6136072A (en) * 1998-01-20 2000-10-24 Electric Power Research Institute, Inc. Apparatus and method for the removal of contaminants in gases
US5948143A (en) * 1998-01-20 1999-09-07 Electric Power Research Institute, Inc. Apparatus and method for the removal of contaminants in gases
US5980612A (en) * 1998-01-21 1999-11-09 Compliance Environmental Management, Inc. Adsorbent activated carbon fiber sheet filter and method of regeneration
WO2000074819A1 (en) 1999-06-04 2000-12-14 Flair Corporation Rotating drum adsorber process and system
US6372289B1 (en) * 1999-12-17 2002-04-16 Corning Incorporated Process for manufacturing activated carbon honeycomb structures
US6527837B2 (en) 2000-03-30 2003-03-04 Nichias Corporation Rotor and sealing device for rotary adsorber
DE10032385B4 (en) * 2000-07-06 2005-07-14 M + W Zander Facility Engineering Gmbh Process for the regeneration of electrically conductive adsorbents loaded with organic substances
FR2815273B1 (en) * 2000-10-13 2003-03-28 Rivard Daniel PROCESS FOR DESORPTION OF AN ADSORBENT CARTRIDGE ON-BOARD ON ROLLING EQUIPMENT AND AN INSTALLATION FOR CARRYING OUT THIS PROCESS
US6375716B1 (en) * 2000-12-13 2002-04-23 Ut-Battelle, Llc Device for separating CO2 from fossil-fueled power plant emissions
CA2367818C (en) 2001-01-18 2010-05-11 Electric Power Research Institute, Inc. Method and apparatus for renewable mercury sorption
GB0106082D0 (en) * 2001-03-13 2001-05-02 Mat & Separations Tech Int Ltd Method and equipment for removing volatile compounds from air
US6905534B2 (en) * 2001-04-16 2005-06-14 Electric Power Research Institute, Inc. Method and apparatus for removing vapor phase contaminants from a flue gas stream
CA2381610C (en) 2001-04-16 2010-07-06 Electric Power Research Institute, Inc. Method and apparatus for removing vapor phase contaminants from a flue gas stream
GB0117212D0 (en) * 2001-07-16 2001-09-05 Mat & Separations Tech Int Ltd Filter element
US6752853B2 (en) 2002-10-31 2004-06-22 Samsung Electronics Co., Ltd. Article and method for elimination of hydrocarbon emissions from printer exhaust
US7309379B2 (en) * 2002-11-08 2007-12-18 Tw Environmental, Inc. Moving bed adsorber/desorber and low flow (high yield) desorber devices and their methods of use
US7276098B2 (en) * 2003-10-17 2007-10-02 Kx Technologies, Llc Tangential in-line air filter
US20050217481A1 (en) * 2004-03-31 2005-10-06 Dunne Stephen R Rotary adsorbent contactors for drying, purification and separation of gases
US8080095B2 (en) * 2006-05-10 2011-12-20 The Board Of Trustees Of The University Of Illinois Steady state tracking desorption system and method
US7781361B2 (en) * 2006-05-11 2010-08-24 Corning Incorporated Method for regeneration of activated carbon catalyst beds
US8052783B2 (en) * 2006-08-25 2011-11-08 Ut-Battelle Llc Rotary adsorbers for continuous bulk separations
US20080083336A1 (en) * 2006-10-09 2008-04-10 Michael Ford Tschantz Electrically conductive adsorptive honeycombs for drying of air
US7871460B2 (en) * 2007-02-23 2011-01-18 Tw Environmental, Inc. System and method for a moving bed adsorber for contaminant removal
US20090249952A1 (en) * 2008-04-03 2009-10-08 Corning Incorporated Method and system for sorption of liquid or vapor phase trace contaminants from a fluid stream containing an electrically charged particulate
SE532586C2 (en) * 2008-06-04 2010-02-23 Eero Erma Drying system with circulating gas
US8940072B2 (en) 2009-02-27 2015-01-27 Inventys Thermal Technologies Inc. Parallel passage fluid contactor structure
NO332547B1 (en) * 2009-07-10 2012-10-22 Statoil Asa Compact absorption-desorption process using concentrated solution
TW201138933A (en) * 2010-05-14 2011-11-16 Cherng Jye Air Cond Co Ltd Adsorbent material fluidized cyclotron cleaner
US10315159B2 (en) 2010-08-27 2019-06-11 Inventys Thermal Technoogies Inc. Method of adsorptive gas separation using thermally conductive contactor structure
CN103180028B (en) 2010-08-27 2016-07-06 英温提斯热力技术有限公司 The method using thermal conductive contact device structure adsorption seperation of gas
US9155561B2 (en) 2013-03-06 2015-10-13 Stryker Trauma Sa Mini-rail external fixator
US10531896B2 (en) 2015-08-10 2020-01-14 Stryker European Holdings I, Llc Distraction tube with wire clamp
TWI776252B (en) * 2020-10-08 2022-09-01 昇詳工程有限公司 Switchable organic exhaust gas treatment device and operation method thereof

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59177119A (en) * 1983-03-28 1984-10-06 Nippon Soken Inc Dehumidifying apparatus
DE3517105C1 (en) * 1985-05-11 1985-11-28 Daimler-Benz Ag, 7000 Stuttgart Process for removing constituents from a gas stream by adsorption onto activated charcoal
US4737164A (en) * 1984-07-06 1988-04-12 Seinajoen Kylmakone A ja T Saikkonen Ky Process for recovering contaminants from gases
DE4104513A1 (en) * 1990-02-14 1991-08-29 Chmiel Horst Regeneration method for adsorbent carbon - by electrical heating of carbon material which has been removed from its locating unit and pressed into shapes or fibres
EP0450888A1 (en) * 1990-03-31 1991-10-09 Taikisha, Ltd. Rotary gas treating apparatus
US5169414A (en) * 1990-07-03 1992-12-08 Flakt, Inc. Rotary adsorption assembly
DE4225272A1 (en) * 1992-07-31 1994-02-03 Bluecher Gmbh Adsorption filter for air purification or off-gases - contains adsorber granules, e.g. active carbon, fixed on a support which can be heated, e.g. electrically, to regenerate the filter
EP0627252A1 (en) * 1993-06-03 1994-12-07 Taikisha, Ltd. Rotary adsorption/desorption gas treating apparatus
EP0684071A2 (en) * 1994-05-26 1995-11-29 Corning Incorporated Electrically heatable activated carbon bodies for adsorption and desorption applications

Family Cites Families (44)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1912784A (en) * 1931-03-31 1933-06-06 Silica Gel Corp Rotary adsorber unit
US2617986A (en) * 1949-01-24 1952-11-11 Jefferson Lake Sulphur Co Rotatable adsorption apparatus
US3197944A (en) * 1961-08-07 1965-08-03 Hayes Inc C I Rotary adsorber having intermittent movement
US3183649A (en) * 1961-08-29 1965-05-18 Mass Transfer Inc Stepwise rotary adsorber including inflatable seal
SE332052B (en) * 1967-07-20 1971-01-25 Munters C
GB1274909A (en) * 1968-11-20 1972-05-17 Getters Spa Improvements in or relating to getter pumps
US3626671A (en) * 1969-05-02 1971-12-14 Air Prod & Chem Adsorber element and temperature controlled adsorber purification system
US3734293A (en) * 1970-03-04 1973-05-22 Air Prod & Chem Thermoelectric adsorber
US4134743A (en) * 1970-03-31 1979-01-16 Gas Developments Corporation Desiccant apparatus and method
US3844737A (en) * 1970-03-31 1974-10-29 Gas Dev Corp Desiccant system for an open cycle air-conditioning system
US3795730A (en) * 1971-03-29 1974-03-05 J Kalvinskas Carbon adsorption-reduction process for nitric oxides
US3780498A (en) * 1972-03-31 1973-12-25 Universal Oil Prod Co Sulfur oxides removal system
US4012206A (en) * 1972-12-02 1977-03-15 Gas Developments Corporation Air cleaning adsorption process
US3885977A (en) * 1973-11-05 1975-05-27 Corning Glass Works Anisotropic cordierite monolith
JPS5198679A (en) * 1975-02-26 1976-08-31
DK148195C (en) * 1977-01-10 1986-04-01 Erling Lauritz Anderberg GAS DEHUMIDIFIER
US4127691A (en) * 1977-06-20 1978-11-28 Corning Glass Works Thermal shock resistant honeycomb structures
US4293423A (en) * 1977-10-18 1981-10-06 Rohm And Haas Company Process and apparatus for ion exchange by use of thermally regenerable resin
JPS56163721A (en) * 1980-05-23 1981-12-16 Mitsubishi Heavy Ind Ltd Stanchion structure for gas treating equipment
JPS5726331A (en) * 1980-07-24 1982-02-12 Toyobo Co Ltd Air cooling system and air conditioning system using activated carbon fiber
DE3031446A1 (en) * 1980-08-20 1982-07-22 Mittex AG, 9490 Vaduz METHOD FOR CAREFULLY DRYING HEAT-SENSITIVE GOODS, DEVICE FOR CARRYING OUT THE METHOD AND SYSTEM WITH SUCH DEVICES
JPS57124637A (en) * 1981-01-26 1982-08-03 Toshiba Corp Air-conditioning apparatus
US4409006A (en) * 1981-12-07 1983-10-11 Mattia Manlio M Removal and concentration of organic vapors from gas streams
US4589892A (en) * 1983-04-07 1986-05-20 Bry-Air, Inc. Sequenced modular bed carousel dehumidifier
US4574874A (en) * 1983-04-07 1986-03-11 Pan Tech Management Corp. Chemisorption air conditioner
US4599225A (en) * 1983-12-15 1986-07-08 Internorth, Inc. Continuous flow separation with moving boundary sorption
US4548802A (en) * 1983-12-15 1985-10-22 Internorth, Inc. Continuous flow separation with moving boundary sorption
DE3465703D1 (en) * 1983-12-21 1987-10-08 Ruetgerswerke Ag Method for continuously purifying exhaust gaz with active coal
US4522726A (en) * 1984-07-30 1985-06-11 Progress Equities Incorporated Advanced separation device and method
JPS62110747A (en) * 1985-11-08 1987-05-21 Shinryo Air Conditioning Co Ltd Regeneration of active carbon
DE3609981A1 (en) * 1986-03-25 1987-10-01 Bayer Ag SURFACE SIZING AGENT FOR PAPER
US4778492A (en) * 1987-02-19 1988-10-18 Advanced Separation Technologies Incorporated Continuous gas treatment method and apparatus for adsorption processes
US4775484A (en) * 1987-03-09 1988-10-04 Life Systems, Inc. Method and apparatus for the continuous separation of contaminants from a fluid mixture
JPS63236514A (en) * 1987-03-25 1988-10-03 Toyobo Co Ltd Gas adsorption treatment method
DE3836856A1 (en) * 1987-10-28 1989-05-11 Daikin Ind Ltd SOLVENT RECOVERY DEVICE, THIS USING SOLVENT RECOVERY CIRCUIT SYSTEM AND GASKET DESIGN
AT389822B (en) * 1988-07-08 1990-02-12 Andritz Ag Maschf METHOD FOR CONTINUOUSLY CLEANING GASES OF CARRYING LOADED MATERIALS AND DEVICE FOR ITS IMPLEMENTATION
US5124023A (en) * 1988-11-28 1992-06-23 Union Oil Company Of California Continuous removal of polynuclear aromatics from hydrocarbon recycle oil
US5017202A (en) * 1989-04-13 1991-05-21 Taikisha Ltd. Gas treating apparatus
US5110328A (en) * 1989-06-07 1992-05-05 Kabushiki Kaisha Kobe Seiko Sho Solvent adsorber and solvent recovery system
US5057128A (en) * 1990-07-03 1991-10-15 Flakt, Inc. Rotary adsorption assembly
FR2667801B1 (en) * 1990-10-11 1992-12-04 Air Liquide PROCESS AND EQUIPMENT FOR SEPARATION BY ADSORPTION OF AT LEAST ONE CONSTITUENT OF A GASEOUS MIXTURE.
US5176005A (en) * 1991-06-24 1993-01-05 Baltimore Aircoil Company Method of conditioning air with a multiple staged desiccant based system
JP2557307B2 (en) * 1992-10-22 1996-11-27 日立造船株式会社 NOx adsorption removal method
US5451444A (en) * 1993-01-29 1995-09-19 Deliso; Evelyn M. Carbon-coated inorganic substrates

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS59177119A (en) * 1983-03-28 1984-10-06 Nippon Soken Inc Dehumidifying apparatus
US4737164A (en) * 1984-07-06 1988-04-12 Seinajoen Kylmakone A ja T Saikkonen Ky Process for recovering contaminants from gases
DE3517105C1 (en) * 1985-05-11 1985-11-28 Daimler-Benz Ag, 7000 Stuttgart Process for removing constituents from a gas stream by adsorption onto activated charcoal
DE4104513A1 (en) * 1990-02-14 1991-08-29 Chmiel Horst Regeneration method for adsorbent carbon - by electrical heating of carbon material which has been removed from its locating unit and pressed into shapes or fibres
EP0450888A1 (en) * 1990-03-31 1991-10-09 Taikisha, Ltd. Rotary gas treating apparatus
US5169414A (en) * 1990-07-03 1992-12-08 Flakt, Inc. Rotary adsorption assembly
DE4225272A1 (en) * 1992-07-31 1994-02-03 Bluecher Gmbh Adsorption filter for air purification or off-gases - contains adsorber granules, e.g. active carbon, fixed on a support which can be heated, e.g. electrically, to regenerate the filter
EP0627252A1 (en) * 1993-06-03 1994-12-07 Taikisha, Ltd. Rotary adsorption/desorption gas treating apparatus
EP0684071A2 (en) * 1994-05-26 1995-11-29 Corning Incorporated Electrically heatable activated carbon bodies for adsorption and desorption applications

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 009, no. 032 (C - 265) 9 February 1985 (1985-02-09) *

Also Published As

Publication number Publication date
US5628819A (en) 1997-05-13
TW313530B (en) 1997-08-21

Similar Documents

Publication Publication Date Title
US5628819A (en) Method and apparatus for continuous adsorption of adsorbable contaminates and adsorber regeneration
EP0684071B1 (en) Electrically heatable activated carbon bodies for adsorption and desorption applications
US8052783B2 (en) Rotary adsorbers for continuous bulk separations
US5658372A (en) System and method for adsorbing contaminants and regenerating the adsorber
EP0745416B1 (en) Device for removal of contaminants from fluid streams
US5308457A (en) Self-contained system for controlling gaseous emissions from dilute organic sources and a process for using that system
EP0578371B1 (en) A sorbing sheet and a sorbing laminate
US6964695B2 (en) Method and equipment for removing volatile compounds from air
US20100212495A1 (en) Sorbent Structure Applicable for Carbon Dioxide Capture
WO1996009104A1 (en) Electrically conductive sorption system and method
US5908490A (en) Organic solvent recovering system and organic solvent recovering method
JP2013059760A (en) Adsorption unit, adsorption device, and method for regenerating thereof
WO2010151271A1 (en) Method and apparatus for gas removal
JPH0157045B2 (en)
US5759496A (en) Apparatus for removing VOC's from an exhaust gas stream
KR100834800B1 (en) Honeycomb adsorptive catalytic element having both adsorption and catalysis function for voc simultaneously and manufacturing method thereof, voc removal method and apparatus thereby
KR20010083897A (en) Thermomembrane method and device
JP3994157B2 (en) Method and apparatus for purifying gases containing organic contaminants
JP2002102693A (en) Method for regenerating conductive adsorbing agent charged with organic substance
US20080083336A1 (en) Electrically conductive adsorptive honeycombs for drying of air
CA2485915A1 (en) Sorption concentrator with electrically heated desorption regeneration
KR980008301A (en) Organic gas adsorption removal sheet and organic gas adsorption removal element
JP3265219B2 (en) Exhaust treatment device
WO1998056491A1 (en) A combined concentrator-oxidation system for voc emission control
JP2001070737A (en) Solvent recovery apparatus and solvent recovery method

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): BR CA CN JP KR MX

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): AT BE CH DE DK ES FI FR GB GR IE IT LU MC NL PT SE

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
NENP Non-entry into the national phase

Ref country code: CA

122 Ep: pct application non-entry in european phase