SU545591A1 - Wastewater treatment method - Google Patents

Description

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The invention relates to wastewater treatment methods and can be used for the wastewater treatment of the microbiological and hydrolysis industry in the production of amino acids and biologically active substances (antibiotics, enzymes, etc.).

The biological method of wastewater treatment is known, however, its implementation requires large sizes of sewage treatment plants (treatment in aeration tanks, biofilters), maintaining a culture of activated sludge, regeneration of sludge, sludge dewatering by coagulation and filtration, burning sludge in kilns, which is cost-effective only in large-scale industries, such as pulp and paper production.

For relatively small-scale microbiological and hydrolysis production, methods are acceptable for cleaning by coagulation of salts of iron, chromium, ammonium and other metals, bleaching with activated carbon. However, coagulating agents reduce BPKb by 30-40%. Activated carbons are effective for lightly colored solutions and for the purification of waste water from the production of amino acids, enzymes and other biologically active substances, the consumption of coal is 30-40% of the volume of the clarified liquid, which makes its use unprofitable.

There is a method of sewage treatment with ferric chloride treatment, filtration through layers of gravel sand and angrazite, followed by sorption with activated carbon. The reduction in BiiKs by this method is 70-75%. To increase the degree of purification from organic compounds by the proposed method, chemical treatment is carried out by the introduction of milk of lime and then orthophosphoric

acid to pH 8.0-9.0. The sorption is carried out with an ion exchange resin based on metaphenylene diamine hydrochloride with formaldehyde and resorcinol (IA-1).

Purified water is treated with lime milk with a solids content of 20-30%. With this, the pH of the mixture rises to 11.0-11.5 and a flocculent precipitate is formed. The stirring is carried out for 10-30 minutes. Then the mixture is neutralized with orthophosphoric acid and stirred for 10-30 minutes. At the same time, the formed polymer calcium phosphate gel has a high sorption capacity in this pH range. When reducing RP sorption capacity

gel falls. Fresh impurities are sorbed by organic impurities. The sorption process ends after 10-30 minutes after the start of contact. The spent calcium phosphate gel is separated from the liquid by automatic production filter presses.

The precipitate after filtration is elastic plates with moisture content of 55-70%, which are conveniently transported.

For further purification of the waste liquid, it is passed through a brightening microporous resin column IA-1. The filtrate after the clarifying columns is a colorless, odorless, transparent liquid. The percentage of cnnezi MIC 80-90%.

Resin IA-1 regenerate 2 and. alkali solution at the rate of two volumes per resin volume. The regenerating solution from the clarifying column is shifted together with the effluent at the neutralization stage, which is available for cleaning, before treatment with Ca phosphate. Its volume is based on the volume of wastewater being treated. The spent Ca phosphate precipitate is swept at 500-600 ° C for 1–3 hours and Ca phosphate that is suitable for fertilizer is obtained.

Example 1. A 10 liter of post-yeast brewing gpdrolizodrozhzhevoj dark brown plant with a content of suspended particles of 1.87 g / l and stirred for 10 minutes with 500 g of 20% milk of lime. The mixture is then neutralized with orthophosphoric acid to a pH of 8.2-8.5, stirred for 15 minutes and filtered through a belting fabric under vacuum. The resulting filtrate is transparent, l: yellow color with. The precipitate is dense, with a humidity of 60%. The filtrate is passed through a column of resin at the rate of 30 volumes of filtrate per volume of resin. Get purified stock, clear and colorless c. The reduction rate of BODB is 80%.

Resin IA-1 in the column is recovered 600 ml 2 n. solution KaOP. The alkaline eluate is directed at the lime treatment stage.

Example 2. Alkaline eluate obtained

during the regeneration of clarifying columns loaded with an IA-1 sorbent, in the technological production of L-lysine has the following characteristics: mg Og / l, optical density (chromaticity) 16.8 (at 535 mmk, cuvette 10 mm). The eluate is neutralized with nitric acid to RP 5.0 and mixed for 10 minutes with 20% milk of lime, taken at the rate of 5% of milk per volume of eluate. The mixture is neutralized with orthophosphoric acid to an RP of 8.2-8.5 and stirred for 15 minutes. Then the addition of milk of lime and orthophosphoric acid is repeated in the same doses and in the same regimen. The resulting suspension is filtered through belting fabric.

The filtrate after separation of the precipitate is a slightly colored liquid with a color of 0.6 and mg Og / l. To further discolor and reduce BOD, the filtrate is passed through a column of IA-1 resin in an amount of 35 volumes of filtrate per volume of resin at a rate of 4 volumes of solution per volume of resin in the column. Bleached liquid is obtained with BOD-920. The degree of reduction in BODR is 85%.

Claims (2)

1. A method of sewage treatment by chemical treatment, filtration and sorption, characterized in that, in order to improve the degree of purification from organic compounds 1Y, chemical treatment is carried out by injecting milk of lime and then orthophosphoric acid to RP 8.0-9.0. 2. Method according to c. 1, characterized in that the sorption is carried out by an ion exchange resin based on hydrochloric acid metaphenylene diamine with formaldehyde and resorcin.