SU1031909A1 - Method for cleaning water from suspended substanges - Google Patents

Abstract

1. METHOD FOR CLEANING WATER FROM SUSPENDED SUBSTANCES with polyelectrolyte flocculant, characterized by the fact that, in order to increase the purity of the purification and simplify the purification process of acid effluent, water-soluble cationic polyurethane semiconductor containing 0.81 is used as flocculant. ion centers. 2. The way pop. 1, I differ by the fact that flocculating nt is introduced in the amount of 10–25 mr; l (I

Description

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This invention relates to a wastewater treatment method using polyp electrolyte cells.

It is known that for purification of natural waters such synthetic materials as polyacrylamide, polyethyleneimine, copolymers of maleic anhydride with vinyl acetate L are used.

The closest in technical essence to the present invention is a method for the purification of high-flowing waters using pbleacrylamide 2}

The disadvantage of polyacrylamide (PAD) is hydrolytic instability and poor solubility in water, which reduces its effectiveness as flocculant. In addition, it thickens at low and high temperatures, which significantly complicates the dissolution and dosing of flocculant and in some cases results to block the filters. All in all, this greatly complicates the process of acid wastewater treatment.

The purpose of the invention is to improve the degree of purification and infect the process of purifying acidic wastewater from suspended substances. .

The goal is achieved by using as a flocculant water-soluble cationic polyurethanesmicarbazides containing 0.8-1.66 macv / g of polymer ion centers, preferably in an amount of 10-25 mg / l.

Cationic polyurethane-semicarbazide (KPUS) is obtained on the basis of the macro isocyanates and chain extenders, containing no ternary two hydrogen atoms and a tertiary amino group. Macrodiisocyanates are products of aliphatic or aromatic reactions.

diisocyanates (preferably toluene diisocyanate) with complex or simple oligoesters (mol. M. 10005000) with terminal hydroxyl groups.

P-methyldiethanolamine and various bifunctional hydrazine derivatives (preferably hydrazine and dicarboxylic acid hydroxides with alkyl radicals in the side chain) can be used as chain extenders. The molar ratio of oligoester, diisocyanate, P-methyldiethanolamine and hydrazine derivative, respectively, is 1: (3,747) :( 2.3-5B (0.5-1.0).

CPC, containing not less than 0.8 meq / g of polymer ion centers, is an aqueous solution or dispersion with a dry matter concentration of 20–30%, pH 3.5–6.5 unlimitedly dissolved in water.

PRI me R. The studied industrial wastewaters are characterized by the following indicators: pH 1.0, acidity 400-1380 mg-eq / l, amount of suspended particles (2-9.0) g / l,

To 500 ml-Wastewater with a concentration of suspended substances of 2, 3 g / l, a 0.1% solution of cationic polyurethane semicarbazide, containing 1.1 meq / g of polymer ion centers, is added in an amount of 10 mg / l and mixed in for 1 min After 45 minutes of settling, a sample is taken and the amount of suspended particles in the sample is determined by dry residue. The clarification efficiency is 74%.

Comparative data on the degree of purification of acidic wastewaters with flocculant polyurethane-semicarbazides and polyacrylamide (the prototype is presented in the table.

10 598.0 1-4 KPUS Based on Macrodiisocyanate and Hydrate Hydrozine Hydrate 15 156.1 Number of ionic centers 1.1 meq / g of polymer 2960.15 5-9 KPUS based on Macrodiisocyanate and hydrazide 2604.5 butyl malonic acid 2175.0 292.1 4.0 9.6 1.20 480.0 2300.0 3.2 1.0 1280.0 6250.0

The number of ionic centers 0.8 mEq / g polymer

KPUS based

Macrodiisocyanate and Dihydrazid Butyl Malo Nova Acid

Number of ion & x centers 1.1 mEq / g polymer

KPUS based

macrodioisocyanate and butylmalonic acid dihydrazide

The number of ionic centers 1.1 mEq / g polymer

9-22 KPUS on the basis of macrodiisocyanate and butylmalonic acid dihydrazide

Number of ionic centers 1.66 meq / g of polymer

26 KPUS based; Macrodiisocyanate and Butylmalonic Acid Dihydrazide

Number of ionic centers 1.66 meq / g of polymer

Table continuation

As can be seen from the table, using polyurethane-semicarbazides proposed as flocculants, the maximum degree of purification of acidic effluent reaches 97-98.2% at a dose of 1012 mg / l (experiments 23 and 24), while the PAA at the same doses the maximum degree of purification is slightly lower and equal to 93.4-97% (examples 28 and 29).

At the same time, the CCPs are more hydrolytically and temperature stable, since for at least 10 days their aqueous solutions remain unchanged pH (whereas in the solutions of PAA already on the fourth day the continuation of the table

hydrolysis of the amide groups is given), and 5-10% of the CCPC solutions have a thickening temperature (8% PAA 2.5 ° C).

The technical and economic efficiency of the method consists in simplifying the cleaning process, since, due to the high water solubility, hydrolytic and temperature stability of the proposed filters, their doping is facilitated, filters are blocked, and their efficiency remains unchanged for a long time. In addition, the range of domestic flocculants for water purification is expanding.

Claims (2)

1. METHOD FOR WATER PURIFICATION FROM WEIGHTED SUBSTANCES with a polyelectrolyte flocculant, characterized in that, in order to increase the degree of purification and simplify the process of acid wastewater treatment, water-soluble cationic polyurethane-semicarbazides containing 0.81.66 meq / g of polymer are introduced as a flocculant. 2. The method of pop. 1, distinguished by the fact that the flocculant is administered in an amount of 10-25 ^ m ^ / l. 1 1031909 ¹