CA2058440C - Use of mixed hydroxy ethers as aids for drying solids materials - Google Patents
Use of mixed hydroxy ethers as aids for drying solids materials Download PDFInfo
- Publication number
- CA2058440C CA2058440C CA002058440A CA2058440A CA2058440C CA 2058440 C CA2058440 C CA 2058440C CA 002058440 A CA002058440 A CA 002058440A CA 2058440 A CA2058440 A CA 2058440A CA 2058440 C CA2058440 C CA 2058440C
- Authority
- CA
- Canada
- Prior art keywords
- solids
- water
- carbon atoms
- surfactant
- alkyl group
- Prior art date
- Legal status (The legal status 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 status listed.)
- Expired - Fee Related
Links
- 239000007787 solid Substances 0.000 title claims abstract description 28
- 239000000463 material Substances 0.000 title claims description 7
- JSPLKZUTYZBBKA-UHFFFAOYSA-N trioxidane Chemical class OOO JSPLKZUTYZBBKA-UHFFFAOYSA-N 0.000 title abstract description 16
- 238000001035 drying Methods 0.000 title description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 24
- 125000004432 carbon atom Chemical group C* 0.000 claims abstract description 12
- 125000000217 alkyl group Chemical group 0.000 claims abstract description 11
- 239000003245 coal Substances 0.000 claims description 17
- 238000000034 method Methods 0.000 claims description 14
- 239000000571 coke Substances 0.000 claims description 3
- 238000001914 filtration Methods 0.000 claims description 3
- 239000010865 sewage Substances 0.000 claims description 3
- ZNQVEEAIQZEUHB-UHFFFAOYSA-N 2-ethoxyethanol Chemical compound CCOCCO ZNQVEEAIQZEUHB-UHFFFAOYSA-N 0.000 claims 6
- 230000018044 dehydration Effects 0.000 abstract description 21
- 238000006297 dehydration reaction Methods 0.000 abstract description 21
- 238000005187 foaming Methods 0.000 abstract description 3
- 239000004094 surface-active agent Substances 0.000 description 42
- 239000000243 solution Substances 0.000 description 6
- 238000007792 addition Methods 0.000 description 5
- ULUAUXLGCMPNKK-UHFFFAOYSA-N Sulfobutanedioic acid Chemical class OC(=O)CC(C(O)=O)S(O)(=O)=O ULUAUXLGCMPNKK-UHFFFAOYSA-N 0.000 description 3
- 239000012153 distilled water Substances 0.000 description 3
- 125000002496 methyl group Chemical group [H]C([H])([H])* 0.000 description 3
- 238000005065 mining Methods 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 125000002704 decyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 2
- 150000002170 ethers Chemical class 0.000 description 2
- 239000002736 nonionic surfactant Substances 0.000 description 2
- 125000001400 nonyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 2
- 125000002347 octyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 150000003254 radicals Chemical class 0.000 description 2
- WPWHSFAFEBZWBB-UHFFFAOYSA-N 1-butyl radical Chemical compound [CH2]CCC WPWHSFAFEBZWBB-UHFFFAOYSA-N 0.000 description 1
- SNRUBQQJIBEYMU-UHFFFAOYSA-N Dodecane Chemical group CCCCCCCCCCCC SNRUBQQJIBEYMU-UHFFFAOYSA-N 0.000 description 1
- 229920006063 Lamide® Polymers 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 150000001298 alcohols Chemical class 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 125000001204 arachidyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 125000000484 butyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 125000006165 cyclic alkyl group Chemical group 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 125000003438 dodecyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 150000002118 epoxides Chemical class 0.000 description 1
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 125000003187 heptyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 125000004051 hexyl group Chemical group [H]C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])* 0.000 description 1
- -1 hydroxy-- Chemical class 0.000 description 1
- 238000009533 lab test Methods 0.000 description 1
- 125000002960 margaryl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 125000001421 myristyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- 125000001196 nonadecyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 125000000913 palmityl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 125000002958 pentadecyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 125000001147 pentyl group Chemical group C(CCCC)* 0.000 description 1
- 229920000151 polyglycol Polymers 0.000 description 1
- 239000010695 polyglycol Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 125000001436 propyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
- 125000004079 stearyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 239000002352 surface water Substances 0.000 description 1
- 125000002889 tridecyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 125000002948 undecyl group Chemical group [H]C([*])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])C([H])([H])[H] 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
- 238000009736 wetting Methods 0.000 description 1
- 239000004711 α-olefin Substances 0.000 description 1
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F26—DRYING
- F26B—DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM
- F26B5/00—Drying solid materials or objects by processes not involving the application of heat
- F26B5/005—Drying solid materials or objects by processes not involving the application of heat by dipping them into or mixing them with a chemical liquid, e.g. organic; chemical, e.g. organic, dewatering aids
Abstract
The use of mixed hydroxyethers of the general formula I
R10-(CH2CH20)x-CH2-CH(OH)R2 (I) in which R1 denotes an alkyl group having 1 to 10 carbon atoms, R2 denotes an alkyl group having 8 to 20 carbon atoms, and x denotes a number in range from 1 to 20, as auxiliaries for the dehydration of water-containing finely divided solids, gives solids having a low water content without foaming in the water separated therefrom.
R10-(CH2CH20)x-CH2-CH(OH)R2 (I) in which R1 denotes an alkyl group having 1 to 10 carbon atoms, R2 denotes an alkyl group having 8 to 20 carbon atoms, and x denotes a number in range from 1 to 20, as auxiliaries for the dehydration of water-containing finely divided solids, gives solids having a low water content without foaming in the water separated therefrom.
Description
a os ~ ~~yo Use of mixed hydroxyethers as auxiliaries for the dehydration of solids The invention relates to the use of mixed hydroxyethers of the general formula I
R10-(CH2CH20)x-CH2-CH(OH)R2 (I) in which R1 denotes an alkyl group having 1 to 10 carbon atoms, R2 denotes an alkyl group having 8 to 20 carbon atoms and x denotes a number in the range from 1 to 20 as auxilaries for the dehydration of water-containing finely divided solids.
In many branches of industry, e.g. in mining or in sewage treatment plants, large amounts of finely divided solids having high water contents, which have to be dehydrated before further processing of the solids or their disposal, are formed. Thus, for example, the dehydration of water-containing coal or coke is a central process in the processing of fuels based on coal.
The maximum allowable values for the water content of these materials demanded by the market can often be adhered to only with difficulty, since, for example, the coal supplied is produced in very fine particles due to the extensive mechanization of the underground coal mining. Currently, about 38% of the run-of-mine coal is fines having a particle diameter in the range from 0.5 to lOmm; a further 14% is duff having a particle diameter below that.
-z- ~o~~y~a It is known to use surfactants as dehydration auxiliaries for the dehydration of water-containing finely divided solids, in particular coals, which make it possible to reduce the residual moisture of fines and duff. This is explained by the property of the surfactant to reduce the surface tension and the capillary pressure of water in the material to be extracted. At the same time, this reduces the adhesive energy which must be supplied to remove the surface water. This leads to improved dehydration, when surfactants are used, while the amount of energy remains unchanged.
Dialkyl sulfosuccinates (USD- 2,266,954) and nonionic surfactants of the type of alkylphenol polyglycol ethers [Erzmetall 30, 292 (1977)] have been described as surfactant-based dehydrating auxiliaries of the above mentioned types. However, these surfactants have the disadvantage of showing excessive foaming, which leads to considerable problems in the processing plants, in particular in the recirculation of the water which is usually employed.
The invention is based on the finding that nonionic surfactants of the general formula I increase the dehydration rate without foaming and reduce the residual moisture of the dehydrated solids when employed in water/solid systems.
The group R1 of the mixed hydroxyethers to be used according to the invention of the general formula I is a straight-chain or branched or cyclic alkyl group having 1 to 10 carbon atoms, for example a methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl or decyl group. Alkyl groups of the above list having 1 to 4 carbon atoms are preferred. The group RZ in the general formula I is an alkyl group having 8 to 20 carbon atoms, for example an octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl or eicosyl group, in particular an :~ ;.
~058'1%D
alkyl group form the above list having 12 to 16 carbon atoms, straight-chain R2 radicals being particularly preferred. x in the general formula I is a number in the range form 1 to 20, the range from 2 to 15 being preferred.
In accordance with their use according to the invention, the mixed hydroxyethers of the general formula I have to be water-soluble. It may occur that the water solubility is not quite sufficient, if the mixed hydroxyethers of the general formula I have low values of x and long-chain radicals R1 and/or R2 where the chain lengths are within the abovementioned limits; however, the required water solubility can be obtained by increasing the value for x within the abovementioned range.
The mixed hydroxyethers of the general formula I are described in DE-A 3,723,323; they can be obtained by reacting,ethoxylated alcohols of the general formula II
R10(CH2CH20)x-OH (II) with epoxides of alpha-olefins of the formula III
R2 - CH - CH (III) ~ 2 ~O
in the presence of catalysts, in which Rl, R2 and x are as defined above.
In accordance with their preparation and the starting materials used, which are in most cases employed in the form of technical grade mixtures, the mixed hydroxyethers to be used according to the invention of the general formula I can also be present as technical grade mixtures.
In accordance with an advantageous embodiment of the invention, the mixed hydroxyethers of the general formula I are used in an amount of 0.5 to 10, in particular 3 to 8, kg per m3 of the water to be removed from the finely t .~., ~~~~44~
divided solids.
As mentioned at the beginning, the mixed hydroxyethers of the general formula I are suitable in particular for the dehydration of water-containing finely divided coal or coke; however, they can also be used in the dehydration of other water/solid systems, for example for beneficiated ores or gangue materials in ore mining, sewage sludges and the like. In this respect, a further advantage of the surfactants to be used according to the invention of the general formula I is that they are compatible with surfactants of different composition, which may be present, for example with dialkyl sulfo-succinates such as di-noctyl sulfosuccinates or polyacry-lamides, which were added to the solids to be dehydrated in previous processing steps.
The invention is illustrated in more detail below by way of preferred embodiments.
In the examples, washed fines having the following analytical data were used:
6.8 % by weight of water 3.7 % by weight of ash (wf; calculated with respect to water-free coal) 27.2 % of volatile components (waf; calculated with respect to water- and ash-free coal) Screen analysis of the fines gave the following values:
- 0.5 mm 1.5 %
0.5 - 2.0 mm 23.1 %
R10-(CH2CH20)x-CH2-CH(OH)R2 (I) in which R1 denotes an alkyl group having 1 to 10 carbon atoms, R2 denotes an alkyl group having 8 to 20 carbon atoms and x denotes a number in the range from 1 to 20 as auxilaries for the dehydration of water-containing finely divided solids.
In many branches of industry, e.g. in mining or in sewage treatment plants, large amounts of finely divided solids having high water contents, which have to be dehydrated before further processing of the solids or their disposal, are formed. Thus, for example, the dehydration of water-containing coal or coke is a central process in the processing of fuels based on coal.
The maximum allowable values for the water content of these materials demanded by the market can often be adhered to only with difficulty, since, for example, the coal supplied is produced in very fine particles due to the extensive mechanization of the underground coal mining. Currently, about 38% of the run-of-mine coal is fines having a particle diameter in the range from 0.5 to lOmm; a further 14% is duff having a particle diameter below that.
-z- ~o~~y~a It is known to use surfactants as dehydration auxiliaries for the dehydration of water-containing finely divided solids, in particular coals, which make it possible to reduce the residual moisture of fines and duff. This is explained by the property of the surfactant to reduce the surface tension and the capillary pressure of water in the material to be extracted. At the same time, this reduces the adhesive energy which must be supplied to remove the surface water. This leads to improved dehydration, when surfactants are used, while the amount of energy remains unchanged.
Dialkyl sulfosuccinates (USD- 2,266,954) and nonionic surfactants of the type of alkylphenol polyglycol ethers [Erzmetall 30, 292 (1977)] have been described as surfactant-based dehydrating auxiliaries of the above mentioned types. However, these surfactants have the disadvantage of showing excessive foaming, which leads to considerable problems in the processing plants, in particular in the recirculation of the water which is usually employed.
The invention is based on the finding that nonionic surfactants of the general formula I increase the dehydration rate without foaming and reduce the residual moisture of the dehydrated solids when employed in water/solid systems.
The group R1 of the mixed hydroxyethers to be used according to the invention of the general formula I is a straight-chain or branched or cyclic alkyl group having 1 to 10 carbon atoms, for example a methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl or decyl group. Alkyl groups of the above list having 1 to 4 carbon atoms are preferred. The group RZ in the general formula I is an alkyl group having 8 to 20 carbon atoms, for example an octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, nonadecyl or eicosyl group, in particular an :~ ;.
~058'1%D
alkyl group form the above list having 12 to 16 carbon atoms, straight-chain R2 radicals being particularly preferred. x in the general formula I is a number in the range form 1 to 20, the range from 2 to 15 being preferred.
In accordance with their use according to the invention, the mixed hydroxyethers of the general formula I have to be water-soluble. It may occur that the water solubility is not quite sufficient, if the mixed hydroxyethers of the general formula I have low values of x and long-chain radicals R1 and/or R2 where the chain lengths are within the abovementioned limits; however, the required water solubility can be obtained by increasing the value for x within the abovementioned range.
The mixed hydroxyethers of the general formula I are described in DE-A 3,723,323; they can be obtained by reacting,ethoxylated alcohols of the general formula II
R10(CH2CH20)x-OH (II) with epoxides of alpha-olefins of the formula III
R2 - CH - CH (III) ~ 2 ~O
in the presence of catalysts, in which Rl, R2 and x are as defined above.
In accordance with their preparation and the starting materials used, which are in most cases employed in the form of technical grade mixtures, the mixed hydroxyethers to be used according to the invention of the general formula I can also be present as technical grade mixtures.
In accordance with an advantageous embodiment of the invention, the mixed hydroxyethers of the general formula I are used in an amount of 0.5 to 10, in particular 3 to 8, kg per m3 of the water to be removed from the finely t .~., ~~~~44~
divided solids.
As mentioned at the beginning, the mixed hydroxyethers of the general formula I are suitable in particular for the dehydration of water-containing finely divided coal or coke; however, they can also be used in the dehydration of other water/solid systems, for example for beneficiated ores or gangue materials in ore mining, sewage sludges and the like. In this respect, a further advantage of the surfactants to be used according to the invention of the general formula I is that they are compatible with surfactants of different composition, which may be present, for example with dialkyl sulfo-succinates such as di-noctyl sulfosuccinates or polyacry-lamides, which were added to the solids to be dehydrated in previous processing steps.
The invention is illustrated in more detail below by way of preferred embodiments.
In the examples, washed fines having the following analytical data were used:
6.8 % by weight of water 3.7 % by weight of ash (wf; calculated with respect to water-free coal) 27.2 % of volatile components (waf; calculated with respect to water- and ash-free coal) Screen analysis of the fines gave the following values:
- 0.5 mm 1.5 %
0.5 - 2.0 mm 23.1 %
2.0 - 6.3 mm 51.5 %
+ 6.3 mm 23.9 %.
The efficiency of the mixed hydroxyethers of the general formula I in the dehydration was determined by treating the fines with aqueous solutions of the mixed hydroxy-- ~0~~~~~
ethers of defined concentration and dehydrating them under defined conditions; the residual moisture obtained with and without the addition of surfactant was determined according to DIN 51718 by drying at 106°C and weighing.
The present examples are laboratory tests in which the amounts of surfactants used in kg are based on 1000 kg each of the solids to be dehydrated (calculated as water-free solids). In practice, the necessary amounts of surfactants will be less than the ones used in the examples; moreover, the necessary amounts of surfactants used depend on the amount of the water to be removed from the solids, when the solids are dehydrated in practice.
The structure of the mixed hydroxyethers tested of the general formula I and their abbreviations used below can be seen from Table 1.
The term "surfactant" used here and hereinafter refers to the mixed hydroxyethers of the general formula I.
Table 1 Mixed hydroxyethers of the formula I
R10- ( CHZCHzO ) =-CHz-CH ( OH )-Rz Surfactant Rl Rz x CH3 n-ClzHzs 2 B CH3 n-ClzHzs 4 C n-C~H9 n-ClzHzs 2 D n-C4H9 n-C16H33 2 Example 1 Dehydration in a pressure filter 50 g of coal were added to 400 ml of distilled water or surfactant solutions in distilled water and were filtered after being exposed for 60 seconds. This was done by using a pressure filter which consisted of a sealed neutral filter which was filled with the material to be dehydrated. The dehydration was carried out by subjecting the filter to a pressure of 3 bar. The dehydration time was 30 seconds. The filter material used was a filter fabric having a mesh size of 0.2 mm.
The surfactants tested, the surfactant concentration of the solution with which the coal was treated, the amount of surfactant calculated per 1000 kg of coal and the residual moisture determined are summarized in Table 2.
Table 2 Pressure filter test Surfactant Surfactant Amount of sur- Residual concentra- factant (kg) moisture tion per 1000 kg (% by wt.) (g/1) of coal A 1.0 g g,g 8 1.0 g g,5 C 1.0 g ~,2 D 1.0 g g,9 without the addition of surf actant - - 11. 6 As can be seen from Table 2, the residual moisture of the dehydrated coal is substantially reduced, when the surfactants to be used according to the invention are used compared with that without the addition of surfactant.
Example 2 Dehydration in a centrifuge In this example, a bucket-type centrifuge was used with which at revolutions of 300 to 3,400 per minute - ' - Q~~4~
centrifugal characteristic values of 15 to 2000 can be obtained. Perforated plates having sieve openings of 0.4 x 4.0 mm were used as sieve plate for the centrifuge. The surfactants used as filtering aids (mixed hydroxyethers of the general formula I) were dissolved in distilled water in concentrations of 0.1 g/1 and 1.0 g/1. To carry out the tests, 400 ml each of the surfactant-containing solutions were poured into a glass vessel. 25 g of coal were dipped into each of these solutions. The wetting time was in each case 60 seconds. This was followed by predehydration of the samples at a constant dripping time of 180 seconds. The values obtained in the predehydration of the samples, the surfactant concentration and the amount of surfactant calculated per 1000 kg of coal are summarized in Table 3.
To dehydrate the predehydrated samples in the bucket-type centrifuge, centrifugal characteristic values of 43.2, 111 and 389 (corresponding to revolutions of 500, 800 and 1500 per minute) were established. The dehydration time was 30 seconds. The results obtained are summarized in Table 4.
In a second test series, a surfactant concentration of 1.0 g/1 at a centrifugal characteristic value of 111 (corresponding to revolutions of 800 per minute) was tested at dehydration times of 5, 10 and 30 seconds. The results obtained are summarized in Table 5.
As can be seen from Tables 3 to 5, all surfactants tested have a very good effect on the dehydration. Even in the predehydration (Table 3), the efficiency of the surfactants compared with a sample without the addition of surfactant became obvious. While the untreated sample had a residual moisture of 43.6 % after a dripping time of 180 seconds, this value could be reduced down to 26.5 % by means of the surfactants used according to the invention. This corresponds to a relative reduction in residual moisture by 39 %.
-As can be seen from Tables 4 and 5, the residual moisture could be reduced not only by increasing the centrifugal characteristic value but also by adding the surfactants to be used according to the invention.
A surfactant solution of 0.1 g/1 made it possible to reduce the residual moisture to 4.0 % by weight at a centrifugal characteristic value of 111. A surfactant solution of 1.0 g/1 decreased the residual moisture down to 3.0 %. These values can also be reached with short dehydration times.
Table 3 Centrifuge test Results of the predehydration Surfactant Surfactant Amount of Residual concentra- surfactant moisture tion (g/1) (kg) per (% by wt.) 1000 kg of coal A 10 16 26.5 H 1.0 16 30.3 C 10 16 30.1 1.0 16 34.8 without surfactant - - 43.6 A 0.1 1.6 37.5 0.1 1.6 31.9 _ g _ Table 4 Centr ifugal dehydration Revolutions per minute 500 800 1500 500 800 1500 S Centrifugal characteristic value 43.2 111 389 43.2 111 389 Surfactant concentra-IO tion (g/1) 0.1 0.1 0.1 1.0 1.0 1.0 Surfactant Residual moisture A 5.7 5.3 3.5 3.6 3.1 2.6 B 4.5 4.0 3.7 3.? 3.0 2.5 C 5.8 4.7 3.1 6.0 4.8 3.3 15 D 6.9 5.9 4.1 7.0 5.2 3.7 without addit-ion of surfac taut 7.8 6.1 3.9 7.8 6.1 3.9 Table 5 20 Results at a centrifugal racteristic value 111 cha of Dehydration times) 5 10 30 Surfactant Residual moisture (% by wt.) 25 A 3.6 3.2 3.1 3.8 3.5 3.0 C 5.5 5.1 4.8 D 5.7 5.5 5.2 without surfactant 6.8 6.7 6.1 ~
+ 6.3 mm 23.9 %.
The efficiency of the mixed hydroxyethers of the general formula I in the dehydration was determined by treating the fines with aqueous solutions of the mixed hydroxy-- ~0~~~~~
ethers of defined concentration and dehydrating them under defined conditions; the residual moisture obtained with and without the addition of surfactant was determined according to DIN 51718 by drying at 106°C and weighing.
The present examples are laboratory tests in which the amounts of surfactants used in kg are based on 1000 kg each of the solids to be dehydrated (calculated as water-free solids). In practice, the necessary amounts of surfactants will be less than the ones used in the examples; moreover, the necessary amounts of surfactants used depend on the amount of the water to be removed from the solids, when the solids are dehydrated in practice.
The structure of the mixed hydroxyethers tested of the general formula I and their abbreviations used below can be seen from Table 1.
The term "surfactant" used here and hereinafter refers to the mixed hydroxyethers of the general formula I.
Table 1 Mixed hydroxyethers of the formula I
R10- ( CHZCHzO ) =-CHz-CH ( OH )-Rz Surfactant Rl Rz x CH3 n-ClzHzs 2 B CH3 n-ClzHzs 4 C n-C~H9 n-ClzHzs 2 D n-C4H9 n-C16H33 2 Example 1 Dehydration in a pressure filter 50 g of coal were added to 400 ml of distilled water or surfactant solutions in distilled water and were filtered after being exposed for 60 seconds. This was done by using a pressure filter which consisted of a sealed neutral filter which was filled with the material to be dehydrated. The dehydration was carried out by subjecting the filter to a pressure of 3 bar. The dehydration time was 30 seconds. The filter material used was a filter fabric having a mesh size of 0.2 mm.
The surfactants tested, the surfactant concentration of the solution with which the coal was treated, the amount of surfactant calculated per 1000 kg of coal and the residual moisture determined are summarized in Table 2.
Table 2 Pressure filter test Surfactant Surfactant Amount of sur- Residual concentra- factant (kg) moisture tion per 1000 kg (% by wt.) (g/1) of coal A 1.0 g g,g 8 1.0 g g,5 C 1.0 g ~,2 D 1.0 g g,9 without the addition of surf actant - - 11. 6 As can be seen from Table 2, the residual moisture of the dehydrated coal is substantially reduced, when the surfactants to be used according to the invention are used compared with that without the addition of surfactant.
Example 2 Dehydration in a centrifuge In this example, a bucket-type centrifuge was used with which at revolutions of 300 to 3,400 per minute - ' - Q~~4~
centrifugal characteristic values of 15 to 2000 can be obtained. Perforated plates having sieve openings of 0.4 x 4.0 mm were used as sieve plate for the centrifuge. The surfactants used as filtering aids (mixed hydroxyethers of the general formula I) were dissolved in distilled water in concentrations of 0.1 g/1 and 1.0 g/1. To carry out the tests, 400 ml each of the surfactant-containing solutions were poured into a glass vessel. 25 g of coal were dipped into each of these solutions. The wetting time was in each case 60 seconds. This was followed by predehydration of the samples at a constant dripping time of 180 seconds. The values obtained in the predehydration of the samples, the surfactant concentration and the amount of surfactant calculated per 1000 kg of coal are summarized in Table 3.
To dehydrate the predehydrated samples in the bucket-type centrifuge, centrifugal characteristic values of 43.2, 111 and 389 (corresponding to revolutions of 500, 800 and 1500 per minute) were established. The dehydration time was 30 seconds. The results obtained are summarized in Table 4.
In a second test series, a surfactant concentration of 1.0 g/1 at a centrifugal characteristic value of 111 (corresponding to revolutions of 800 per minute) was tested at dehydration times of 5, 10 and 30 seconds. The results obtained are summarized in Table 5.
As can be seen from Tables 3 to 5, all surfactants tested have a very good effect on the dehydration. Even in the predehydration (Table 3), the efficiency of the surfactants compared with a sample without the addition of surfactant became obvious. While the untreated sample had a residual moisture of 43.6 % after a dripping time of 180 seconds, this value could be reduced down to 26.5 % by means of the surfactants used according to the invention. This corresponds to a relative reduction in residual moisture by 39 %.
-As can be seen from Tables 4 and 5, the residual moisture could be reduced not only by increasing the centrifugal characteristic value but also by adding the surfactants to be used according to the invention.
A surfactant solution of 0.1 g/1 made it possible to reduce the residual moisture to 4.0 % by weight at a centrifugal characteristic value of 111. A surfactant solution of 1.0 g/1 decreased the residual moisture down to 3.0 %. These values can also be reached with short dehydration times.
Table 3 Centrifuge test Results of the predehydration Surfactant Surfactant Amount of Residual concentra- surfactant moisture tion (g/1) (kg) per (% by wt.) 1000 kg of coal A 10 16 26.5 H 1.0 16 30.3 C 10 16 30.1 1.0 16 34.8 without surfactant - - 43.6 A 0.1 1.6 37.5 0.1 1.6 31.9 _ g _ Table 4 Centr ifugal dehydration Revolutions per minute 500 800 1500 500 800 1500 S Centrifugal characteristic value 43.2 111 389 43.2 111 389 Surfactant concentra-IO tion (g/1) 0.1 0.1 0.1 1.0 1.0 1.0 Surfactant Residual moisture A 5.7 5.3 3.5 3.6 3.1 2.6 B 4.5 4.0 3.7 3.? 3.0 2.5 C 5.8 4.7 3.1 6.0 4.8 3.3 15 D 6.9 5.9 4.1 7.0 5.2 3.7 without addit-ion of surfac taut 7.8 6.1 3.9 7.8 6.1 3.9 Table 5 20 Results at a centrifugal racteristic value 111 cha of Dehydration times) 5 10 30 Surfactant Residual moisture (% by wt.) 25 A 3.6 3.2 3.1 3.8 3.5 3.0 C 5.5 5.1 4.8 D 5.7 5.5 5.2 without surfactant 6.8 6.7 6.1 ~
Claims (13)
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. The process of dehydrating water-containing finely divided solids, comprising contacting said solids with a mixed hydroxyether of formula I
R10-(CH2CH20)x-CH2-CH(OH)R2 (I) wherein R1 represents an alkyl group having 1 to 10 carbon atoms R2 represents an alkyl group having 8 to 20 carbon atoms, and x represents a number from about 1 to about 20.
R10-(CH2CH20)x-CH2-CH(OH)R2 (I) wherein R1 represents an alkyl group having 1 to 10 carbon atoms R2 represents an alkyl group having 8 to 20 carbon atoms, and x represents a number from about 1 to about 20.
2. The process as in claim 1 wherein R1 represents an alkyl group having 1 to 4 carbon atoms.
3. The process as in claim 1 wherein R2 represents an alkyl group having 12 to 16 carbon atoms.
4. The process as in claim 1 wherein x represents a number from about 2 to about 15.
5. The process as in claim 1 wherein said mixed hydroxyether is present in an amount of from about 0.5 to about 10 kg per m3 of the water to be removed from said solids.
6. The process as in claim 1 wherein said mixed hydroxyether is present in an amount of from about 3 to about 8 kg per m3 of the water to be removed from said solids.
7. The process as in claim 1 wherein said solids are selected from the group consisting of finely divided coal and coke.
8. The process as in claim 1 wherein said solids are selected from the group consisting of beneficiated ores and gangue materials.
9. The process as in claim 1 wherein said solids are selected from the group consisting of sewage sludges.
10. The process as in claim 1 wherein said mixed hydroxyether is present in an aqueous system.
11. The process as in claim 1 including filtering said solids after contacting said solids with said mixed hydroxyether.
12. The process as in claim 11 wherein said filtering step is conducted under pressure.
13. The process as in claim 1 including centrifuging said solids after contacting said solids with said mixed hydroxyether.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DEP3918274.6 | 1989-06-05 | ||
| DE3918274A DE3918274A1 (en) | 1989-06-05 | 1989-06-05 | USE OF HYDROXYMISCHETHERS AS A SOLVENT FOR SOLIDS HEATING |
| PCT/EP1990/000851 WO1990015295A1 (en) | 1989-06-05 | 1990-05-28 | Used of mixed hydroxy ethers as aids for drying solids materials |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CA2058440A1 CA2058440A1 (en) | 1990-12-06 |
| CA2058440C true CA2058440C (en) | 2001-03-27 |
Family
ID=6382085
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA002058440A Expired - Fee Related CA2058440C (en) | 1989-06-05 | 1990-05-28 | Use of mixed hydroxy ethers as aids for drying solids materials |
Country Status (11)
| Country | Link |
|---|---|
| US (1) | US5215669A (en) |
| EP (1) | EP0475969B1 (en) |
| AU (1) | AU631647B2 (en) |
| BR (1) | BR9007418A (en) |
| CA (1) | CA2058440C (en) |
| DE (2) | DE3918274A1 (en) |
| NO (1) | NO178838C (en) |
| PT (1) | PT94261A (en) |
| TR (1) | TR24599A (en) |
| WO (1) | WO1990015295A1 (en) |
| ZA (1) | ZA904275B (en) |
Families Citing this family (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE4019174A1 (en) * | 1990-06-15 | 1992-01-02 | Henkel Kgaa | EXTRACTS FOR FILTRATION AND / OR DEHUMIDIFICATION OF MINERAL AND CARBON SUSPENSIONS |
| DE4218050A1 (en) * | 1992-06-01 | 1993-12-02 | Henkel Kgaa | Process for dewatering fine particulate suspensions |
| DE4218074A1 (en) * | 1992-06-01 | 1993-12-02 | Henkel Kgaa | Process for dewatering fine particulate suspensions |
| US5670056A (en) * | 1995-04-17 | 1997-09-23 | Virginia Tech Intellectual Properties, Inc. | Chemical-mechanical dewatering process |
| US6526675B1 (en) | 1999-06-07 | 2003-03-04 | Roe-Hoan Yoon | Methods of using natural products as dewatering aids for fine particles |
| US6855260B1 (en) | 1999-06-07 | 2005-02-15 | Roe-Hoan Yoon | Methods of enhancing fine particle dewatering |
| US6375853B1 (en) * | 2000-03-17 | 2002-04-23 | Roe-Hoan Yoon | Methods of using modified natural products as dewatering aids for fine particles |
| US6799682B1 (en) | 2000-05-16 | 2004-10-05 | Roe-Hoan Yoon | Method of increasing flotation rate |
| AU2000277395B2 (en) | 2000-09-28 | 2005-11-10 | Roe-Hoan Yoon | Methods of using natural products as dewatering aids for fine particles |
| JP4022595B2 (en) * | 2004-10-26 | 2007-12-19 | コニカミノルタオプト株式会社 | Imaging device |
| AP2447A (en) * | 2005-02-04 | 2012-08-31 | Mineral And Coal Technologies Inc | Improving the seperation of diamond from gangue minerals |
Family Cites Families (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2266954A (en) * | 1939-08-26 | 1941-12-23 | American Cyanamid Co | Wetting agent in settling of oe pulps |
| US2975123A (en) * | 1957-11-04 | 1961-03-14 | Int Nickel Co | Dewatering metal ore concentrates |
| US3194758A (en) * | 1961-05-24 | 1965-07-13 | Petrolite Corp | Method of agglomerating finely divided solids in an aqueous medium |
| US3327402A (en) * | 1964-12-28 | 1967-06-27 | Shell Oil Co | Solvent drying of coal fines |
| LU47975A1 (en) * | 1965-02-12 | 1966-08-12 | ||
| US4014104A (en) * | 1975-06-23 | 1977-03-29 | Continental Oil Company | Drying of lignite using nonaqueous solvents |
| JPS5613099A (en) * | 1979-07-10 | 1981-02-07 | Nichireki Chem Ind Co Ltd | Treating method of sludge |
| JPS5784708A (en) * | 1980-11-18 | 1982-05-27 | Kao Corp | Improving agent for filtration/dehydration property of metal hydroxide slurry |
| GB2152490B (en) * | 1984-01-09 | 1987-09-03 | Dow Chemical Co | Mineral dewatering method |
| DE3723323C2 (en) * | 1987-07-15 | 1998-03-12 | Henkel Kgaa | Hydroxy mixed ethers, processes for their preparation and their use |
| US4866856A (en) * | 1987-10-13 | 1989-09-19 | The Standard Oil Company | Solids dewatering process and apparatus |
| US4990264A (en) * | 1989-10-13 | 1991-02-05 | Sherex Chemical Company, Inc. | Ore dewatering process and compositions therefor |
-
1989
- 1989-06-05 DE DE3918274A patent/DE3918274A1/en not_active Withdrawn
-
1990
- 1990-05-28 DE DE59005545T patent/DE59005545D1/en not_active Expired - Fee Related
- 1990-05-28 US US07/777,389 patent/US5215669A/en not_active Expired - Fee Related
- 1990-05-28 AU AU56685/90A patent/AU631647B2/en not_active Ceased
- 1990-05-28 EP EP90908227A patent/EP0475969B1/en not_active Expired - Lifetime
- 1990-05-28 CA CA002058440A patent/CA2058440C/en not_active Expired - Fee Related
- 1990-05-28 BR BR909007418A patent/BR9007418A/en not_active Application Discontinuation
- 1990-05-28 WO PCT/EP1990/000851 patent/WO1990015295A1/en active IP Right Grant
- 1990-06-01 TR TR90/0510A patent/TR24599A/en unknown
- 1990-06-04 ZA ZA904275A patent/ZA904275B/en unknown
- 1990-06-04 PT PT94261A patent/PT94261A/en not_active Application Discontinuation
-
1991
- 1991-10-11 NO NO914001A patent/NO178838C/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| TR24599A (en) | 1992-01-01 |
| EP0475969B1 (en) | 1994-04-27 |
| US5215669A (en) | 1993-06-01 |
| ZA904275B (en) | 1991-02-27 |
| DE59005545D1 (en) | 1994-06-01 |
| WO1990015295A1 (en) | 1990-12-13 |
| NO914001D0 (en) | 1991-10-11 |
| AU631647B2 (en) | 1992-12-03 |
| AU5668590A (en) | 1991-01-07 |
| PT94261A (en) | 1991-02-08 |
| BR9007418A (en) | 1992-06-16 |
| CA2058440A1 (en) | 1990-12-06 |
| EP0475969A1 (en) | 1992-03-25 |
| NO178838C (en) | 1996-06-12 |
| NO914001L (en) | 1991-10-11 |
| NO178838B (en) | 1996-03-04 |
| DE3918274A1 (en) | 1990-12-06 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4207186A (en) | Process for dewatering mineral concentrates | |
| CA2058440C (en) | Use of mixed hydroxy ethers as aids for drying solids materials | |
| US4210531A (en) | Process for dewatering mineral concentrates | |
| US4156649A (en) | Dewatering ore concentrates with branched alkyl ethoxylated alcohol | |
| DD159202A1 (en) | METHOD FOR THE EFFICIENCY OF A WAESS-RICH INCLOSURE OF CARBON | |
| US4206063A (en) | Dewatering aid composition | |
| US2864765A (en) | Dewatering ore concentrates | |
| US4231868A (en) | Process for dewatering mineral and coal concentrates | |
| US4323365A (en) | Dewatering of solid residues of carbonaceous materials | |
| CA1252016A (en) | Mineral dewatering method | |
| GB2225260A (en) | Additive compositions for recovering coal fines by froth flotation | |
| US5372727A (en) | Auxiliaries for the filtration and/or dewatering of mineral and coal suspensions | |
| GB2156243A (en) | Froth flotation | |
| EP0423061A1 (en) | Ore dewatering process and compositions therefor | |
| KR0171265B1 (en) | Agent for separation unburned carbon from fly ash | |
| CA2146236A1 (en) | Internal hydroxy mixed ethers | |
| AU556007B2 (en) | Improved mineral dewatering method | |
| WO1992004092A1 (en) | Use of glycerine ethers as dewatering aids for solids | |
| SU1077643A1 (en) | Method of flotation of coal | |
| US4532049A (en) | Dewatering agent compositions for sulfide materials | |
| SU947180A1 (en) | Method for dehydrating coals | |
| SU1704837A1 (en) | Method of coal flotation | |
| GB2184036A (en) | Separation | |
| SU1263354A1 (en) | Method of flotation of coal slimes | |
| US4568475A (en) | Dewatering agent compositions for sulfide materials |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EEER | Examination request | ||
| MKLA | Lapsed |