SU1199761A1 - Method of producing polymer for flocculation of waste water sediment - Google Patents

Abstract

A method for producing a polymer for flocculation of sewage sedimentation by the interaction of a technical polyacrylamide solution containing 1550% of the ammonium salt with formaldehyde and dimethylamine, characterized in that, in order to reduce the consumption of formaldehyde and dimethylamine and reduce the content of the polymer in toxic materials, to reduce the consumption of formaldehyde and dimethylamine and reduce the amount of toxic in the polymer, the amount of toxic gases in order to reduce the consumption of formaldehyde and dimethylamine and reduce the amount of toxic substances in the polymer in order to reduce the consumption of formaldehyde and dimethylamine and to reduce the amount of formaldehyde and dimethylamine. polyacrylamide sodium hydroxide is added to pH 12-12.5, air is blown through this solution to remove ammonia to a residual concentration of 0-20 mg / l, then dimethylamines and formaldehyde are introduced to the molar ratio of polyacrylamide, formaldehyde and dimethylamine in the resulting solution, respectively, 1:

Description

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9d. The invention may be used to obtain reagents used for the flocculation of suspensions and sludges and, in particular, for the flocculation of sediments formed during mechanical, biological and physicochemical treatment of wastewater, before their dehydration on mechanical devices: centrifuges , filter presses and vacuum filters. The purpose of the invention is to reduce the consumption of formaldehyde and dimethylamine and reduce the retention rate; product of toxic low molecular weight mines. P p i. measure 1. To 500 ml of a 1.0% technical polyacrylamide solution — a gel containing 14.7% of sugar; Pyfate ammonium, add 10 ml of a 40% sodium hydroxide solution. Then, through a solution whose pH is 12 , 5, purge for 30 minutes purged and dried air. Thereafter, 6 g of a 37% formaldehyde solution and 9 g of a 33% dimethyl amine (molar ratio of polyacryl amide: formaldehyde: dimethylamine 1:; 1.05: 0.95), heated to 70 ° C., Live at this temperature for 30 minutes, cooled and acidified with hydrochloric acid to a pH of 2.5. The resulting α-reagent solution, in which 1.82% of a polymeric amine containing 3.2 mg eq / g of cationic groups and traces of low molecular weight amines, is used to flocculate the sediment of the primary septic tanks of sewer systems. With a reagent consumption of 0.3% by weight of the solid phase and a separation factor of 1520, the effect of a solid phase in the laboratory centrifuge was 98, 4–99.1%. Comparative npimep la. In a solution of a reagent obtained at the same ratio of components, pH and heating conditions, but not removed from the reaction mass of ammonia, there is 1.2% of a polymeric amine containing 0.38% of cationic groups. The reagent has a significantly worse flocculating effect. At a dose of p agent of 0.3%, the effect of retention of the solid phase in a laboratory centrifuge was 61–63%. Comparative example 16. In a solution of a reagent prepared by the conventional method with a molar ratio of polyacrylamide: formaldehyde: dimethylamine 1: 5.6: 6.0, there is 1.6% of a polymeric amine containing 2.4 mEq / g cationic groups, and 10,800 mg / l of low molecular weight amines. With a reagent dose of 0.3%, the effect of retention in the laboratory centrifuge of the solid phase of the sediment of the primary clarifiers was 83.5-86.7%. Example 2. A reagent obtained at the same ratio of components, pH and heating conditions as in Example 1, but using a solution of technical polyacrylamide gel, in which, after adding sodium hydroxide and blowing air for S h, ammonia was not detected contains 1.84% of a polymeric amine and traces of low molecular weight amines. At a flow rate of reagent of 0.3% by weight of the solid phase, the effect of retention in the laboratory centrifuge of the solid phase of the sediment of the primary clarifiers was 98-99.5%. Example Z. K1.2m3 of a 1.5% aqueous solution of technical polyacrylamide dry containing 50% ammonium sulphate is added 24 liters of a 39% aqueous solution of sodium hydroxide. Then through a solution with a pH of 12.0 barbears. for one hour the air. After blowing air, the ammonia content in the solution decreases to 20 mg / l. To this solution, 19 kg of 37.5% form, aldehyde and 28 kg of 43% dimethylamine (molar ratio of polyacrylamide formaldehyde: dimethylamine 1: 0.95: 1.05) are added, heated to 75 ° C, maintained at this the temperature is 25 minutes, the acidification is cooled and the hydrochloric acid is pH 2.3. I The resulting reagent solution, in which there are 2.39% polymer amine containing 2.83 mg eq / g of cationic groups and 49 mg / l of low molecular weight amines, is used for flocculation of an aerobically stabilized mixture of activated sludge and sediment of primary settlers on a centrifuge firm Alfa Loval. With a centrifuge capacity of 2 m / h, a separation factor of 1500 and a reagent dose of 0.45% by weight of solid, the delayed effect was 97.8%. Comparative example For. The reagent solution obtained by lime, 11997614

This way, it contains 2.03% poly-. Thus, the proposed surfactant number 1 and 8300 mg / l are low, which reduces the consumption of formolecular amines. The effects of the retention of aldehyde and dimethylamine and containing the NIL of the solid phase under the same conditions, toxic in the finished product as in Example 3, is 84.3%. with low molecular weight substances.

Claims (1)

METHOD FOR PRODUCING A POLYMER FOR FLOCULATION OF WASTEWATER SEDIMENTS by reacting a technical polyacrylamide solution containing 1550% ammonium salt with formaldehyde and dimethylamine, characterized in that, in order to reduce the consumption of formaldehyde and dimethylamine and to reduce the content of toxic low molecular weight molecules sodium hydroxide is added to a solution of polyacrylamide to a pH of 12-12.5, air is blown through this solution to remove ammonia to a residual concentration of 0-20 mg / l, then dimethylamines and formaldehyde are added to a mol the ratio of polyacrylamide, formaldehyde and dimethylamine in the resulting solution, respectively, 1: (0.95-1.05) :( 0.95-1.05), heated to 70-75 C, kept at this temperature for 25-30 minutes, cooled and acidified to a pH of 2.3-2.5.