RU2259962C1 - Sewage water biochemical cleaning method - Google Patents

Abstract

FIELD: cleaning of sewage water.

SUBSTANCE: invention relates to biochemical cleaning of sewage water and it can be used for local cleaning of sewage of enterprises, offices and dwelling houses. Proposed method of biochemical cleaning of sewage water includes treatment of sewage water in primary settler, saturation of water with oxygen from air and recirculation of active sludge in aeration tank and cleaning of water in secondary settler. Saturation of water with oxygen from air and recirculation of active sludge is done in aeration tank furnished with bioblocks by means of ejector installed in intake chamber. Preliminary cleaning of water from coarse mechanical impurities is carried out in sand trap with subsequent cleaning of sewage water in biofilter located after secondary settler and chlorine water meter.

EFFECT: improved cleaning, reduced volume of sediment formed in process of cleaning.

2 cl, 1 dwg

Description

The invention relates to biochemical wastewater treatment and can be used for local wastewater treatment from enterprises, institutions, residential buildings.

A known method of biochemical wastewater treatment, which consists in the fact that the wastewater is sequentially treated in the primary sump, aeration tank, secondary sump, then on the biofilter and in the tertiary sump. In the primary sedimentation tank, settling impurities are released, in the aeration tank and the biofilter, the remaining contaminants are oxidized by aerobic microorganisms of activated sludge (aeration tank) and biological film (biofilter). Secondary and tertiary sedimentation tanks are designed to separate sludge and biofilm from purified water [1].

However, during wastewater treatment, a significant amount of excess active, in particular filamentous microorganisms, which do not stand out in secondary and tertiary sedimentation tanks, is formed. In addition, the absence of a sand trap in front of the primary sump leads to disruption of the treatment facilities due to the ingress of large mechanical impurities into the sump and further into the aeration tank, and the absence of recirculation of activated sludge in the treatment plant scheme gives a low cleaning effect.

To fix filamentous bacteria in the cleaning scheme, they are fixed on bioblocks installed in aerotanks, activated sludge are recycled in aerotanks, and a sand trap is installed in front of the primary settler.

The closest technical solution is a method of biochemical wastewater treatment, including wastewater treatment in a biofilter, in the primary sump, in the aeration tank and in the secondary sump, characterized in that in order to increase the degree of purification and reduce the amount of sludge formed, activated sludge from the aeration tank is recycled to the biofilter [2].

The disadvantages of this method is that the scheme does not have a sand trap, and wastewater is supplied directly to the biofilter, which leads to a load calculation, and filamentous bacteria are removed from aeration tanks.

The problem solved by the invention is to increase the degree of purification and reduce the volume of precipitate formed.

This problem is solved by the fact that in the method of wastewater treatment, including their treatment in the primary sump, oxygen saturation and recycling of the active or in the aeration tank, cleaning in the secondary sump, according to the invention, the water is saturated with oxygen and recycling the activated sludge in an aeration tank equipped with bioblocks with the help of an ejector installed in the receiving chamber, the preliminary purification of water from coarse mechanical impurities is carried out in a sand trap with subsequent post-treatment of wastewater in bio This filter is placed after the secondary clarifier and perchloric water dispenser.

The advantage of the proposed method compared to the prototype is the reduction of metal equipment and stabilization of the quality of treated wastewater.

The present invention meets the criterion of "industrial applicability", confirmed by a combination of the following conditions.

The invention is intended for local wastewater treatment from enterprises, institutions, residential buildings.

The drawing shows a schematic diagram of the water technology of the proposed method.

The scheme contains a pumping station 1, a grill 2, a sand trap 3, a primary sump 4, an aeration tank 5, a receiving chamber 6, an ejector 7, a secondary sump 8, a metering chamber 9, a siphon 10, a sand and gravel filter 11, a chlorine water meter 12, a contact tank thirteen.

Wastewater treatment is as follows. The initial sewage pumping station 1 through the grate 2 is fed into the sand trap 3, where large mechanical impurities are retained, then the primary settler 4 passes, enter the aeration tank with a polyethylene load 5, the receiving chamber 6 and the secondary settler 8. To increase the oxidative power of the aeration tank, increase the degree dispersing air, increasing the working dose of activated sludge and fixing filamentous bacteria in the aeration tank, a load in the form of blocks from the rows of a polyethylene mesh is located and the sludge mixture is recycled and the receiving chamber by means of the ejector 7. The distance between the rows of load of 10 cm. In the secondary settling tank activated sludge settles. Wastewater treatment is carried out on a biofilter or sand and gravel filter 11, in front of which a metering chamber 9 and a chlorine water meter 12 are installed. Dosing of chlorine water before purification ensures disinfection of effluents and prevents siltation of the biofilter or sand and gravel filter.

Examples of the method.

A method of wastewater treatment is implemented in the sanatorium "Chemist".

The results of the analysis of wastewater at the inlet and outlet of treatment facilities are shown in table 1.

Table 1. The results of wastewater analyzes of the Khimik sanatorium at the inlet and outlet of treatment plants The name of indicators The results of the analysis, mg / l entrance Exit Suspended matter 298.5 6.3 Oil products 0.09 0.05 Ammonium nitrogen 19.0 0.16 Phosphates 2.6 1,0 SPAS 0.37 0.05 COD 48.5 19.3 Nitrite 0.01 0.05 Nitrates 1,2 30.6 Chlorides 43.5 43.0 Iron 1.25 0.19 Sulphates 38,4 35.5

From table 1 it can be seen that the quality of the treated wastewater at the outlet of the treatment plant meets the requirements of MPC _pkh .

Literature

1. Designer reference. Sewerage of populated areas and industrial enterprises. M .: Stroyizdat, 1963, p. 347-348.

2. RF patent 952762, MKI C 02 F 3/02. The method of biochemical wastewater treatment. / Feofanov Yu.A. / BI No. 31. - 1982.

Claims (2)

1. The method of biochemical wastewater treatment, including wastewater treatment in the primary sump, oxygen saturation and recirculation of activated sludge in the aeration tank, cleaning in the secondary sump, characterized in that air oxygen saturation and recirculation of activated sludge is carried out in an aeration tank equipped with bioblocks, using an ejector installed in the receiving chamber, preliminary purification of water from coarse mechanical impurities is carried out in a sand trap with subsequent post-treatment of wastewater in a biofilter, laid after the secondary sump and chlorine water dispenser. 2. The method according to claim 1, characterized in that the polyethylene loading is used as bioblocks.