SU833566A1 - Method of purifying return waste water - Google Patents

Description

(54) METHOD FOR CLEANING REVERSE SEWAGE WATER

one

The invention relates to methods for the treatment of wastewater from suspended substances and can be used to lighten the circulating effluents of enrichment and metallurgical production.

A known method of purification of wastewater containing suspended solids using a mixture of salts of aluminum and iron i.

The disadvantage of the method is unsatisfactory, the degree of purification of solutions containing suspended particles, peptized with liquid glass. .

but

The purpose of the invention is to improve the degree of purification from suspended substances, peptized with liquid glass.

This goal is achieved using coagulants of a mixture of aluminum and iron salts, while coagulants use a mixture containing the double aluminum salt AlClg-HSQj and natural siderite.

Siderite before use is subjected to roasting with sodium chloride at 400-500 ° C.

In addition, the coagulated mixture is introduced at the rate of 6–20% of the weight of the LUGHHHX substances with a ratio of Altl2 to HS04 and natural siderite equal to 1-2: 1.

The method is illustrated by the following examples.

Example 1. Circulating wastewater from the processing plant, containing up to 600 g / m of suspended solids, peptized (liquid glass), is treated with a mixture containing A1C12-HS04 and natural siderite in a 1: 1 weight ratio at a rate of 80 g / m L Pulp is settled into for 1 hour. At the same time, the clarified part of the effluent in the amount of 78.2% contains on average 30.4 g / m suspended substances. In the supernatant solution, the solids content is 3%, water 97.0%. The overall degree of wastewater treatment from suspended particles is 95%, the degree of purification by a known method is up to 70-80%.

Example 2. Circulating wastewater with the content of suspended substances analogously to example 1 is treated with a mixture of mineral coagulants containing siderite, subjected to segregating roasting for 40 min with NaCI at 400-500 ° С. A mixture containing components at a 1: 1 ratio is introduced at the rate of 80 g / ml. After an hour

Of these, the clarified part of the effluent is 82%, it contains on average 18.6 g / m-weighed substances. In the sludge solution, the solids content is 3.8%, water is 96.2%, the total degree of purification is 97.0%.

Table 1 shows the effect of the consumption of a mixture of coagulants and the ratio of components in it on the indicators of clarification at a ratio of salts and iron; the settling time is 4 g, it is burned.

Table 1

Table 2 presents the results of experiments on the effect of the ratio of aluminum and iron salts on water clarification at a flow rate of a coagulant mixture of 20% by weight of suspended solids, settling time 4 h, burned siderill.

table 2

200

68

0.5: 1

The application of the proposed method provides a high degree of cleaning solutions, peptized liquid with Tekla.

Claims (3)

1. A method for purification of recycled wastewater containing suspended substances, including the introduction of coagulants - a mixture of aluminum and iron salts, characterized in that In order to increase the degree of purification from suspended substances, peptized with liquid glass, a mixture containing the aluminum double salt AlCl2-HSO and natural siderite is used as coagulants. 2. Method according to Claim 1, characterized in that siderite is fired with sodium chloride at 400-500 ° C before use. 3. The method according to Claim 1 and Claim 2, which is based on the fact that the coagulating mixture is administered at the rate of 5-20% by weight of suspended substances with a ratio of components AICl2.HS04 and natural siderite, equal to 1-2: 1. Information sources, taken into account in the examination , 1. Proskurkov V. A., Schmidt L. I. Wastewater treatment in chemical consistency. Chemistry, 1977, p. 106