FR2562564A1 - TREATMENT OF FIBROUS MATERIAL, PARTICULARLY WOOL, AND PLANT FOR CARRYING OUT SAID METHOD - Google Patents

Abstract

THE MATERIAL CROSSES ON AN ENDLESS CONVEYOR 1 A PREWASHING PART 6 OR IT IS TREATED WITH A HYDROCARBON SOLVENT, AN ACIDIFICATION PART 7 OR IT IS TREATED WITH AN ALCOHOLIC SOLUTION IN ACIDIFIED AQUEOUS SOLUTION, AN ELIMINATION PART OF THE ACIDIFIED EXCESS ACID 8 OR IT IS TREATED AGAIN WITH THE HYDROCARBON SOLVENT AND A CARBONIZER 10 OR THE CARBONIZATION TAKES PLACE IN A SOLVENT MEDIUM.

Description

The present invention relates to a material treatment method

  fibrous according to which the material is successively subjected to - a prewash, - an acidification, - an elimination of an excess of acid and

- charring.

  Such methods are particularly applied to

wool processing.

  Known methods of this kind include carbonization in an aqueous medium. Indeed, according to these known processes, acidification is carried out using a solution

  acidified aqueous solution and excess acid is removed by wringing.

  Despite this spinning the water retention of the material, therefore

  wool, for example, is still important.

  Carbonization is therefore of a long duration; it can damage wool fibers and cause

felting.

  The object of the invention is to remedy these drawbacks and to provide a rapid and economical treatment method

  giving a processed material of improved quality.

  For this purpose - the acidification is carried out using an alcoholic solvent in an acidified aqueous solution and - the excess acid is removed from a hydrocarbon solvent, the carbonization being thus carried out in a solvent medium . Carbonization takes place at a higher temperature and can therefore have a short, even shorter, duration.

two minutes.

  In a preferred embodiment of the invention, prewash, acidification, said removal of excess acid and carbonization of the material to be treated are carried out.

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  while the latter moves with the same carpet

perforated conveyor.

  In a particular embodiment of the invention, carbonization is carried out by circulating the material with a conveyor belt in several compartments and by circulating an inert gas at a temperature of the order of 120 C to 1400 C at

  against the current through these compartments.

  The invention also relates to an installation

  for the implementation of the process defined above.

  This installation comprises - an endless skeleton conveyor passing through series of compartments, - means for washing the material in a first series of these compartments, - means for acidifying the material in a second series of these compartments , - means for watering by means of a hydrocarbon solvent in a third series of these compartments with a view to eliminating an excess of acid, and - means for carbonizing the material in a

  fourth series of these compartments.

  Other details and features of the invention

  will emerge from the description of a treatment process

  of fibrous material and of an installation for implementing this method according to the invention, given below by way of nonlimiting example and with reference to the attached drawing. The figure is a schematic view of an installation

  for the treatment of fibrous material according to the invention.

  The installation according to the figure comprises a perforated endless conveyor belt 1 supported by two drums 2, one of which drums the belt. The direction of movement of the upper strand of the conveyor 1 is indicated by the

arrow 3.

  -3- Wool is allowed in 4 in one layer on the

upper section of the carpet 1.

  This wool successively passes through an entry airlock 5, a prewash part 6 o it is treated with a hydrocarbon solvent, an acidification part 7, o it is treated with an alcoholic solvent in an acidified aqueous solution, an elimination part excess

  of acid 8 o it is treated again with the hydro-

  carbonaceous, an airlock 9, a carboniser 10 and a

escape hatch 11.

  These parts 5 to 11 of the installation are mounted

  in line and crossed by the carpet 1.

  The prewash part 6 comprises three sections 12-13, 14-15 and 16-17, the acidification part 7 comprises two sections 18-19 and 20-21 and the removal part

  excess acid 8 includes a section 22-23.

  Each section includes a watering chamber 12, 14, 16, 18, 20 or 22, through which a part of the upper strand of the carpet 1 passes and the funnel bottom of which is provided with a discharge opening 24 leading to a

  decanter 13, 15, 17, 19, 21 or 23.

  Each section also includes a sprinkler device consisting of a number of sprinkler heads 25, a supply line 26 connecting the sprinkler device of the section to the upper part of its decanter and a pump 27 mounted in the pipe 26. From the discharge side of each chamber 12, 14, 16, 18, 20 and 22 are mounted two compression rollers 28 between which the strand passes

  top of carpet 1 and the layer of wool it carries.

  The sprinkler heads 25 are mounted above the wool layer but the chambers 14, 20 and 22 also include a sprinkler head directed towards the

  underside of upper side of carpet 1.

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  The pumps 27 discharge a hydrocarbon solvent under pressure to the sprinklers of the chambers 12, 14 and 16 of the prewash part 6, an alcoholic solvent in acidified aqueous solution under low pressure to the sprinklers of the chambers 18 and 20 of the acidification part 7 and a hydrocarbon solvent under adjustable pressure to the sprinkler devices of the

  chamber 22 of the excess acid removal part 8.

  Hydrocarbon solvent at 49 is introduced into the

  chamber 22 of the excess acid removal part 8.

  To this solvent is added the recycled solvent and watered under adjustable pressure by the sprinkler heads of this part. The solvent causes the excess acid and is collected in the decanter 23 where it forms the lower phase. This lower phase is sent via line 29 to the previous acidification section 20-21; for this purpose the pipe 29 opens into the supply pipe

26 of section 20-21.

  The upper phase of the decanter 23, comprising the hydrocarbon solvent, is allowed to overflow towards the upper part of the decanter 17, as indicated by the

arrow 30 in the figure.

  The decanter 17 is allowed to overflow towards the decanter 15 and the latter towards the decanter 13, as it is

  indicated by the arrows 31 in the figure. The hydro-

  carbonaceous therefore goes upstream against the prewash part

  6 while loading with fat. -

  Watering with a hydrocarbon solvent in the excess acid removal part 8 has in particular the effect of spinning the wool after acidification in traditional methods, but takes only a few seconds and does not

  requires no additional handling of the wool.

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  As the hydrocarbon solvent, it is possible to use

  efficiently and advantageously hexane.

  An alcoholic solution a is introduced at 50

  queuse in the watering chamber 20 of the last sec-

  acidification part 7 and sulfuric acid is added thereto separately by automatic dosing. We

  preferably add 5-10% concentrated sulfuric acid

  very compared to the added amount of alcoholic solution

  than. As alcohol, for example, alcohol is used

  isopropyl. The decanter 21 is overflowed from the bottom

  nier section of the acidification part 7 towards the upper part of the decanter 19 of the first section of this

  part, as indicated by arrow 32 in the figure.

  The acidification of the vegetable matter contained in the wool is done very quickly, thanks to the very high wettability of this by the acid solution, due to the presence of alcohol at average concentrations. The overflow of the decanter 19 feeds the upper part of the decanter 13 of the first section of the prewash part 6, as indicated by the arrow 33 in the figure. In this decanter 13, the alcoholic solution is mixed with the grease-loaded hydrocarbon solvent

  watering the wool in room 12.

  A part of the alcoholic solution supplied by a

  line 34 which is supplied by the overflow of a decan

  Complementary agent 35 described below.

  The prewash is therefore done with the same solvent

  hydrocarbon only the elimination of excess acid and only-

  using recycled hydrocarbon solvent.

  is done in two stages, first using a hydrocarbon solvent

  boné loaded with grease and alcoholic solution in chamber 12 of the first section and using hydrocarbon solvent loaded with grease alone in chambers 14 and 16 of the two other sections of the prewash portion 6. During - 6 - this prewash the wool grease is dissolved and the insoluble impurities, the earth and the sand, are

mechanically driven.

  Insoluble impurities are deposited in the decanters 13, 15, 17, 19 and 21. They are eliminated towards a degreasing device 37 mounted below the decanters. These insoluble impurities are transported using a transport screw to the end of the device located on the side of the excess acid removal part 8 and these impurities are washed against the current by the same hydrocarbon solvent with which the excess acid removal part 8 is fed. This solvent is introduced

  hydrocarbon through line 38 in device 37.

  The grease-loaded hydrocarbon solvent obtained after degreasing the insoluble impurities in the device 3 and the fat solution overflowing from the first settling tank 13 and comprising from 15 to 20% of fat, are pumped by a circulation pump 40; through line 39 to a utility 41 where the solution is deacidified by washing with an aqueous alcoholic solution. The deacidified solution is sent, possibly after refining in a refining unit, to a distillation unit not shown in the figure where it is recovered.

wool grease.

  We can return the alcoholic solution after

  extraction of the acid towards the acidification part 7.

  The sludge drained from the decanters 13, 15, 17, 19 and 21, collected and degreased in the device 37, are sent by the pump 42 through the pipe 43 to the additional decanter 35. As already mentioned, the upper phase of this decanter 35 on the first prewash section. The sludge from this decanter is collected which has a solid matter concentration close to% and it is pumped using the circulation pump 44 through line 45 to a neutralization unit not shown in the figure. After neutralization, this sludge can be distilled in order to recover the alcohol. The sludge is then found in a concentrated aqueous solution at%, with a minimum consumption of steam. This sludge has a fertilizing value and can be used

  as fertilizer, either as is or after drying.

  After acidification and elimination of the excess acid, the wool still deposited on the conveyor belt 1 is made to penetrate via the transfer airlock 9 into the carbonizer 10. This carbonizer 10 is divided into a series of sections 46 in which fans 47 blow an inert gas heated to 120 C to 140 C through the layer of wool to carbonize it - the vegetable matter

impregnated with acid.

  For safety reasons, given the presence of solvents, air which has been

  rid of its oxygen by combustion.

  This gas is introduced via line 48 in the last section 46. This gas rises up the carbonizer against the current while taking charge of solvents. The acid contained

  in plants is thus concentrated.

  The gas from the first section 46 is evacuated and this gas is treated in an annex unit, not shown

  in the figure, where the solvents are recovered.

  Since thanks to the presence of solvents, the water retention of the wool after acidification is reduced, a very rapid rise in temperature and carbonization are possible. Because of the pressure rollers 28 in the excess acid removal part 8, the

  solvent retention is ultimately less than 50%.

  Carbonization can be completed in less than two minutes, at temperatures between 120 and 140 C and the solvents can simultaneously be recovered by

  methodical extraction against the current with an inert gas.

  The number of sections of the carbonizer depends on the desired capacity and the content of

woolen plants.

  The wool is unloaded from the conveyor belt 1

  leaving the carbonizer 10 via the airlock 11.

  This wool is sent to conventional grinding and dusting installations. Then the wool can be deacidified, either with water on a standard line with four or five baths, or using aqueous alcoholic solutions of rinsing and neutralization on

  a line with a perforated conveyor belt.

  In the latter case, a final rinsing with hydrocarbon solvent added with a slight amount of wool grease from the prewash is added to the neutralization. The purpose of this additional treatment, divided into one or two sprinkling sections, is to improve the dedusting of carbonized wool, to reduce the water and alcoholic solvent content before drying and to reload the wool fiber with a sufficient fat content

  to facilitate the following operations, such as carding.

  The process described above is particularly

  indicated for treating wools with a high vegetable content.

  Prewashing, acidification and carbonization are carried out together on a single line of

  treatment in less than three minutes.

  The exceptional speed of the process is due to the very high efficiency of the extraction of fat and soluble impurities, to the very rapid acidification of plant materials thanks to the presence of alcohol at medium concentrations, to the elimination of excess acid using a sprinkling of a hydrocarbon solvent, and rapid charring due to retention

in very reduced wool water.

  The carbonization being carried out in a solvent medium the wool fibers are much less altered after

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  char and felting is reduced. This results in a higher carded ribbon yield. This is due to the fact that the prewash is carried out cold without the intervention of water, that the acidification is carried out in an alcohol medium for a limited period and at acid concentrations lower than the concentrations normally used in known processes, than removal of excess acid is done in a simple and efficient way, that carbonization is done in an extremely fast way and that during the whole

  of the process no mechanical agitation of the wool takes place.

  All of the by-products are recovered and the solvents used are recycled after recovery of the by-products. Since there is no rejection, no

pollution is not caused.

  Despite the complete recovery of the by-products, the steam consumption is reduced and lower than that of known traditional processes and the water consumption is also very low, i.e. less than 1 kg / kg

of material treated.

  More than 95% of the fat extracted can be recovered, either as it is or in the form of lanolin

  refined anhydrous or its derivatives.

  The length of the treatment line is less

  to the lines used to carry out the known methods.

  It should be understood that the invention is in no way limited to the embodiment described above and that many modifications can be made to it, in particular as to the form, the arrangement, the composition and the number

  elements involved in its realization.

  In particular, the prewash part does not necessarily have to include three sections. The number of sections depends on the washed performance of the wool and

especially its fat content.

  _ The acidification part does not necessarily have to have two sections. The number of sections of this

  part depends on the vegetable content of the wool.

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Claims (15)

  1. A method of treating fibrous material according to which the material is successively subjected to - a prewash, - an acidification, - an elimination of an excess of acid and - a carbonization, characterized in that the acidification is carried out using an alcoholic solvent in an acidified aqueous solution and - that the excess acid is removed from a hydrocarbon solvent, carbonization taking place in a solvent medium.   2. Method according to the preceding claim, characterized in that the hydrocarbon solvent used is hexane.   3. Method according to one or other of the   previous claims, characterized in that it realizes   acidification using an alcoholic solvent in an acidified aqueous solution for sulfuric acid at a concentration from 5 to 10%.   4. Method according to either of the claims   previous, characterized in that the prewash is carried out using the hydrocarbon solvent.   5. Method according to either of the claims   above, characterized in that the prewash, the acidification, the said elimination of the excess acid and the carbonization of the material to be treated are carried out while the latter   moves with the same perforated conveyor belt.   6. Method according to the preceding claim, characterized in that each of the operations of - 12 _ - 2562564   prewash, acidification and elimination in at least one section comprising at least one watering device above the carpet and at least one decanter below this carpet and that at least part of the upper phase is recycled forming in the decanter towards the corresponding sprinkler device. 7. Method according to the preceding claim, characterized in that downstream of each sprinkler device the material is compressed and the unbalanced liquid is collected in the settling tank of the section.   8. Method according to either of the claims   previous, characterized in that the sludge settling in the sections preceding the elimination of the excess acid is degreased by transporting it in counter-current with solvent hydrocarbon.   9. Method according to claims 4, 6 and 8,   characterized in that the same hydrocarbon solvent is used for the prewash and the removal of excess acid, that hydrocarbon solvent is added in the excess acid removal section, which 'we send the lower phase forming in this section and comprising the excess acid entrained on the previous acidification section, we send the upper phase forming in this same section partly to the sprinkler -this section and partly by   an overflow to the prewash section.   10. Method according to the preceding claim, characterized in that both the prewash and the acidification are carried out in several sections, that alcoholic solvent in acidified aqueous solution is added to the last section of the acidification part, which '' the upper phase forming in the decanters of the sections of the acidification part by overflow is sent to a previous decanter of this same acidification part, with the exception of the phase - 13 - 2562564 - 13 -   upper forming in the decanter of the first section of the acidification part which is sent to the first section of the prewash part where the prewash is carried out using a mixture of hydrocarbon solvent loaded with grease and alcoholic solution, and send the upper phase forming in the decanter of the section of the elimination part   of excess acid to the last section of the prela-   where the prewash is carried out using solvent hydrocarbon loaded with grease.   11. Method according to claim 8, characterized in that the defatted sludge is transported in an additional decanter from which an alcoholic solution is recovered   which is directed to the first section of the pre-   washing. 12. Method according to the preceding claim, characterized in that neutralizes the sludge from the settling tank   and that the alcohol is recovered by distillation.   13. Method according to either of the claims   above, characterized in that carbonization is carried out by circulating the material with a conveyor belt in several compartments and by circulating an inert gas at a temperature of the order of 120 C to 140 C at   against the current through these compartments.   14. Method according to either of the claims   above, characterized in that the material is subjected after carbonization to deacidification by means of an aqueous alcoholic solution and to rinsing with a hydrocarbon solvent with added fat.   15. Installation for implementing a process   according to either of the preceding claims,   characterized in that it comprises: - an endless conveyor with clearing through series of compartments, - means for washing the material in a first series of these compartments, -14 - 2562564   - means for acidifying the material in a second series of these compartments, - means for watering by means of a hydrocarbon solvent in a third series of these compartments with a view to eliminating an excess of acid , and - means for carbonizing the material in a   fourth series of these compartments.