Clearing of industrial sewage.

The Mechanical way of clearing is based on catching and sedimentation of the weighed substances. For this purpose primenja - jutsja various sediment bowls, peskolovki, zhirolovki, petrotraps.

Sediment bowls happen various depending on the size of the weighed particles in sewage. It is known, that in motionless water at depth of a sediment bowl of 2 m during 1,5 ch drop out particles in diameter of 0,016 mm, during 4 ch - diameter 0,01 mm. Upholding is applied, for example, to allocation of particles of dead rock from sewage rudoobogatitelnyh factories etc.

Peskolovki are intended for removal from sewage grubodispersnyh the weighed substances as the least diameter of detained particles in them makes 0,2-0,25 mm. Speed of movement of sewage in peskolovkah from 0,15 to 0,3 km/s. Duration of stay of sewage in them not less than 30 with.

ZHirolovki apply on meat-packing plants to sewage treatment from fat.

The Mehanohimichesky way of clearing includes upholding with coagulation application, ekstraktsiju. Thus to an intensification of process of upholding of the weighed substances apply koaguljanty and flokkuljanty. In quality koaguljantov use aluminium sulphate, chloride of iron (III) etc. more often. Speed of sedimentation vysokodispersnyh suspensions thus makes 0,35-0,7 mm/with. In quality flokkuljantov apply poliakrilamid (PAA). Thus speed of sedimentation increases by 20-30%, in bolshej degrees than at coagulation are integrated hlopn formed gidroksidov.

ekstraktsija it is applied to extraction from sewage of substances valuable to a national economy (phenols etc.). This process is carried out at processing of drains ekstragentom - an insoluble liquid in water. Thus the substances containing in sewage, pass in ekst-ragent, and then are taken from it. ekstragent can be reused for sewage treatment. In quality ekstragentov apply four-chloride carbon, chloroform, benzene, etc. the Physical and chemical way of clearing consists of an ionic exchange, neutralisation, sorbtsii.

Ionoobmennye sewage treatment methods allow to take and return such valuable substances as nickel in manufacture, zinc, copper, phenols, etc. These methods are based on application synthetic ionoobmennyh pitches (karboksilnyh, phenolic) which are capable to exchange hydrogen ions for others kationy. In the presence of the basic properties of pitch exchange gidroksilnye ions of the bases for others aniony. At ionoobmennom a method there is a replacement of easy ions of hydrogen or alkaline metals ions of colour and heavy metals. In process of replacement of ions there is an accumulation of the fulfilled grains of pitch which then subject regenerations.

Neutralization is carried out by processing of sour sewage izvestju on special constructions or by means of a filtration through magnesite, dolomite, limestones.

Sorbtsija it is recommended for substances which are in water in the dissolved condition. It is carried out by means of the various sorbents, for example activated coal. There is it by a sewage filtration through a sorbent.

The Biochemical way of clearing of industrial sewage is based on aerobic and anaerobnyh processes and used for liquidation of organic substances.