SU975591A1 - Process for treating precipitates after mechanical and biological purification of effluents containing fibrous components - Google Patents

Description

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The method of processing the axles is as follows.

The sediments after biological and mechanical purification of waste water containing fibrous components are subjected to aeration. The duration of the aerobic stabilization process depends on COOTIOCLINAL, the coppers on biological and mechanical cleaning and with an increase in the ratio from 1: 5 to 1: 5 increases from 3 to 8 days.

In the process of aerobic stabilization, the oxidation of easily oxidizable organic matter of the sediment occurs, which prevents rotting and improves the structure of the sediment. In addition, during the aerobic stabilization process, the biofloculating ability of the sediment is improved after biological treatment (active sludge). This leads to the adsorption of finely dispersed fibrous components on the claps of activated sludge and increases the effect of retaining the fibrous components during dehydration of aerobic-stabilized sludge.

Further aeration leads to an improvement in the structure of sediment1 and a reduction in the effect of retention of fibrous components as a result of the dying off of the microflora of activated sludge, the destruction of pops and the accumulation of metabolic products in the system.

Analysis of sludge water for suspended matter is carried out according to a standard procedure in the sample taken for analysis. Ilova water is separated within 0.5-1 hours with gravitational compaction of the sediment. The concentration of suspended substances during the aerobic stabilization process decreases from 1000-600 to 30-70 mg / l, namely, the process is completed before the beginning of the dying of the microflora of active sludge, which prevents the destruction of pops and the accumulation of fine and colloidal fractions.

The content of suspended solids in sludge water greater than 70 mg / l indicates a lack of structurization of the sediment and is accompanied by a decrease in the effect of retention of fibrous components, the concentration of suspended solids in silt water less than 30 mg / l under industrial conditions is not achievable.

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Further aeration leads to an increase in the concentration of suspended substances in the sludge water.

The separation of sludge water can also be carried out by nvTCM filtering: gravitational, floor vacuum or vacuum. .

The method of gravitational compaction is preferable, due to the simplicity of the design and the dependence of the pregel on the filtering material of the city.

The concentration of suspended solids in the sludge water depends on the method of separating the material of the filter septum and varies widely, however, a decrease in the concentration during aerobic stabilization to a minimum value and an increase in

its further aeration occurs at the same time.

The duration of the aerobic stabilization process is determined by the time over which the concentration of suspended solids in the sludge water decreases to the minimum value.

Example 1. A mixture of sediments after biological and mechanical

wastewater treatment of cardboard production in a dry matter ratio of 1: 4 with a solids concentration of 25 kg / m, an ash content of 25%, a resistivity value of USF 2000 -10 cm / g and a concentration of suspended substances in sludge water 900 mg / l, is subjected to aerobic stabilization. Aeration is carried out using a compressor unit. Dissolved oxygen concentration

support not less than 2-3 mg / l. At the same time, the amount of USF and the concentration of suspended substances in the sludge water are monitored.

Duration required

The process is determined by reducing the concentration of suspended solids in the sludge water to a minimum value of 41 mg / l.

Silt water separates from sediment.

with its gravitational compaction

within 30 minutes A decrease in the concentration of suspended solids in the sludge water indicates an increase in the solid phase retention effect.

The magnitude of the CSF in this period does not yet reach its minimum value. However, the subsequent aeration, leading to a decrease in the USF value, is accompanied by an increase in suspended solids in the sludge water due to the destruction of the cotton sludge and dispersion of the sediment.

PRI mme R 2. A mixture of precipitation from biological and mechanical wastewater treatment of cardboard production

in a dry matter ratio of 1: 0.5, with a solids concentration of 20 kg / m, an ash content of 20%, a GF value of 1500-10 cm / g and a concentration of suspended substances in sludge water

620 mg / l is subjected to aerobic stabilization as in example 1.

Example 3. A mixture of sediments after biological and mechanical treatment of waste water from cardboard injection in a dry ratio of 1: 2 with a solids concentration of 25 kg / m, an ash content of 25%, a USF value of 2000-S cm / g and a concentration of suspended solids in sludge 860 mg / l, subjected to aerobic stabilization as in example 1.

; PRI me R 4. A mixture of osschkov after biological and mechanical treatment of wastewater of cardboard production in a dry matter ratio of 1: 2, with a concentration of suspended matter in sludge water of 850 mg / l by coititration of the solid phase 23 kg / m, ash content 23t, USF 1800 is subjected to aerobic stabilization as in Example 1.

Example 5. A mixture of sediments after biological and mechanical treatment of wastewater from paperboard production in a 1: 5 ratio with a concentration of suspended solids in sludge water 1000 mg / l, concentration of the solid phase 28 kg / m-, ash content 26%, USF 2500-10 cm / g subject to azobic stabilization

similar to example 1.

Example b. The mixture of precipitation after biological and mechanical wastewater treatment of cardboard production in the ratio of 1: 5 with a concentration of suspended solids in sludge water 1200 mg / l, the concentration of the solid phase 30 kg / m, ash 20%, USF value 2800-10 cm / g subject to azrobio Stabilization of anaS is logical to Example 1.

The characteristics of the residuals obtained with azrob stabilization according to the proposed and known methods are given in the table.

Effect eaderzhan1; fibrous components are defined as the ratio of the concentration of suspended solids in the sludge water of the initial and aerobic stabilized sludge.

The use of this method will eliminate the stage of dehydration of waste water from the technological scheme of wastewater treatment, eliminate the cost of construction and equipment of the mechanical sediment dewatering shop and reduce electricity consumption for processing sludge 4-6 times, eliminate sludge transportation to the dump, reduce the load of sewage treatment plants due to exclude return fugate.

The annual economic effect from the introduction of this method is only on. treatment facilities of cardboard-ruberoid plants will be 1.71 million rubles.

Claims (3)

1. A method for treating sludge after mechanical and biological treatment of wastewater containing fibrous components by means of erobic stabilization followed by dehydration of aerobic-stabilized sludge separated from sludge water, characterized in that, in order to improve the structure of sediments and increase the degree of retention of fibrous components, aerobic stabilization is carried out until the concentration of suspended substances in sludge water is reduced to 30-70 mg / l. 2. The method according to claim 1, characterized in that the treatment is subjected to precipitation after mechanical and biological wastewater treatment, taken in a ratio of {0.5-5) il by weight of dry matter, respectively. 3. Method according to paragraphs. 1 and 2, characterized in that the dehydration is aerobically stabilized, the sediment is carried out after gravitational compaction for 0.5-1 hours. Sources of information | taken into account in the examination 1. Construction materials. 1976, 9, p. 6-7. 2. Abramov A.V. and others. Intensification of dehydration, precipitation of water and cardboard-ruberoid plants. NIESM, 1978, No. 11, p. 8-10.