DD299821A5 - PROCESS FOR PREPARING LATEX-CONTAINING WASTE WATER - Google Patents

Abstract

The invention relates to a process for the treatment of latex-containing wastewater, as for example in the coating of textile materials with synthetic rubber latex, preferably in the carpet industry anfaellt. The object of the invention is an effective and cost-effective process for the treatment of latex-containing effluents. The invention has for its object to develop a method that allows an improvement in the separation of solid and geloesten constituents from the latex-containing wastewater and avoids re-salting of the treated wastewater. According to the invention, the object is achieved by adding, in a one-step process, latex-containing wastewater as flocculant, coagulation and adsorption agent to non-reusable, neutral-acting, cellulosic textile dust. This allows the complete separation of the solid and dissolved components. Subsequent neutralization of the treated wastewater is not required. {Procedure, one-stage; Wastewater treatment; Separation; components; latex-containing effluents; synthetic rubber; Coating of textile materials; Carpet industry; coagulant; flocculant; adsorbent}

Description

Characteristic of the known state of the art

There are bokannt various methods for the treatment of latex-containing wastewater, in which, for example, added as a primary flocculant FeCl ₃ , AICI ₃ or MgCl ₃ , wherein a strongly acidic wastewater is obtained with an insufficiently settleable or filterable colloid system. In DE-OS 2515162 Ca (OH) ₂ or NaOH are therefore added for neutralization. In addition, in DE-OS 1642850 used as Sekundärflockungsmitto ¹ anionic high molecular weight compounds, such as partially saponified polyacrylamides. The wastewater treated in this way is clarified by blowing air through a flotation or filtered or decanted after sedimentation.

Since only small filter throughputs are achieved because of the fine-pored sludge, the addition of sawdust and the blowing of hot air is recommended in DD-PS 204217. In addition, a method is known in DD-PS 118 205, are used in the cleaning in addition to flocculation and oxidizing agents. DE-PS 503169 and DE-PS 2321 509 describe a process in which synthetic organic polymers are used to remove water-insoluble dyes. DE-PS 2428928 describes a process in which the wastewater is treated in successive combination of primary and secondary flocculants using metal salts and organic polymers. DE-PS 1642886 provides for the use of clay minerals instead of the metal salts.

However, the use of hydrolisiorender metal salts shows a strong pH-dependent cleaning effect, so that with varying wastewater quality also highly fluctuating results are achieved. In order to improve the effect, the use of novel metal salts with enormously acid character is recommended in DE-OS 3417106. However, a subsequent neutralization is essential in this process.

In all known methods is largely based on the approach that commercial chemicals are used. In addition to the high procurement and cost expenses, such methods lead to statements by dissolved chemicals, which lead to high evaporation residues. The treated wastewater can usually not be reused as service water.

Furthermore, the reaction times of the overall process are delayed by the separate implementation of the operations of precipitation initiation, neutralization and coagulation, complicates the technical design and ultimately reaches wastewater levels that have insufficient purity, such as. B. pH and residues.

Object of the invention

The object of the invention is to treat the latex-containing wastewater by an effective and inexpensive process so that it can be reused as service water or can be derived with a small proportion of residues in flowing waters while maintaining the required levels.

Explanation of the essence of the invention

The invention has for its object to develop a method which allows over the known methods using physically and chemically reactive substances to improve the separation of solid and dissolved components from the latex-containing wastewater, with a post-salting of the treated waste water should be avoided.

According to the invention, this object is achieved in that in a one-step process to be treated latex-containing wastewater, optionally after previous precipitation of the filler, such as chalk, flocculation, coagulation and adsorbent so far not reusable, neutral-acting, cellulosic textile etching dust in amounts of 1 -1 Okg per cubic meter of wastewater in powdered form or as a highly concentrated aqueous suspension at temperatures of 5 to 50 ° C is added.

The cellulosic textile etch dust in the dry etching technology of cellulosic Ätzstickb accrues with aluminum sulfate in the embroidery industry, wherein the aluminum sulfate is dehydrated and decarbonated by the thermal-mechanical treatment.

The orfindungsgemäße agent is added to the latexhaitigen wastewater with constant stirring or blowing air. During the Durohmischens takes place the chomisch-Physlkalischo treatment of latexhaitigen waste water. After that will only

stirred slowly until it comes to flocculation.

Surprisingly, it was found that previously not reusable toxtilor Ätzstaub with high

economic benefit for the treatment of latex-containing wastewater can be used.

By synergistic effect in the simultaneous Einklitung the flocculation reaction and physical coagulation and In addition, adsorption is surprisingly saved by known methods of flocculation chemical modification

and the flocculation zoit is shortened until the coagulation products are discontinued. In addition, compound chemicals such as stabilizers, emulsifiers and soaps, bound by adsorption, are entrained to the surface of the cellulosic textile etch dust by its high affinity and entrained in the sewage sludge.

Another significant advantage of this invention is based on the fact that compared to known methods by the

inventive means makes no subsequent addition of a Noutralisationsmittols required. Thus, a

Salination of the treated wastewater avoided.

Flotation, filtration or decantation, separated from the flocculated components and reused as process water or introduced into flowing waters while maintaining the required levels.

Aufführungsbelsplele The invention will be explained below with reference to two embodiments example 1

Latexhaitigen the waste water in a reservoir under slow stirring 1 to 10kg per cubic meter of textile Ätzstaub latexhaltigem waste water, preferably 3 to 5kg, added at a Temperatui of 10 ⁰ C. The following results were achieved:

parameter ME Experiment no. 2 1 4.5 Ätzstaub kg / m ³ 3.8 6.3 reached pH - 6.5 0.5 evaporation residue kg / m ³ 1.0 5 filterable residue g / m ³ 42

After a service life of 8 to 24 hours, preferably 12 to 16 hours, the treated wastewater is separated from the flocculated components by conventional methods such as flotation, filtration or decanting and used as process water or discharged into flowing waters.

Example 2

1 to 10 kg of textile etching dust per cubic meter of latex-containing wastewater, preferably 3 to 5 kg, at a temperature of 23 ° C. are added to the waste-containing wastewater in a collecting tank while stirring slowly. The following results were achieved:

parameter ME Experiment no. 2 1 4.5 Ätzstaub kg / m ³ 3.8 6.3 reached pH - 6.5 0.4 evaporation residue kg / m ^J 0.8 2 filterable residue "* ^ * g / m ³ 38

The-on-prepared wastewater is weiterbehnndelt as in Example 1 on.

Claims (1)

Process for the preparation of latexhaltigom Abwnsse basis of synthetic rubber latex with and without fillers and Compoundchemiknlion, such as stabilizers, emulsifiers and soaps, characterized in that in a one-step process cellulosic textile Ätzstaub in quantities of 1 to 10kg per cubic meter of wastewater at temperatures of 5 to 50 ⁰ C is added as a neutral flocculant, coagulant and adsorbent and the Ausflockten ingredients after a period of 8 to 24 hours from the treated wastewater by known methods, such as flotation, filtration or decanting separated. Field of application of the invention The invention relates to a process for the treatment of letoxhaltigem wastewater, as obtained, for example, in the coating of textlien materials with synthetic rubber latex preferably in the carpet industry.