SU791606A1 - Unit for biological purification of oil-containing water - Google Patents

Description

one

The invention relates to the field of treatment of industrial wastewater, in particular to means of biological treatment, and can be used to clean sea and fresh VOD from oil and oil products, as well as to decontaminate production STOKES of the refining and petrochemical industries.

A device for the biochemical treatment of waste BODs is known, which contains a vertical cleaning tank divided by height by. sections with perforated transverse partitions, overflow pipelines, E located in each section, aerators and a container for collecting activated sludge with activated sludge return pipeline l treatment of heavily polluted water and performance.

The purpose of the invention is to provide the POSSIBILITY of collecting and removing light impurities from the biological treatment zone.

To achieve this goal, in the installation, the transverse partitions 5 are bent. DOWN edge and attached alternately to the opposite walls of the vertical cleaning tank.

In addition, the installation has an additional pre-treatment tank for WATER, which is connected to the lower section of the cleaning tank by an overflow pipe. The overflow pipe of the upper section is connected to the collection tank.

activated sludge, and the return pipeline of excess sludge is connected to the upper section.

FIG. 1 shows the technological scheme of the installation; in fig. 220 is a variant of a sewage treatment plant consisting of two series-connected plants.

The installation contains a vertical cleaning tank 1 with drainage system

25 by tray 2, tank 3 for pre-treatment of WATER and tank 4 for collecting activated sludge, communicating with vertical cleaning tank 30 by filling pipe 5 and pipe- ing.

6 return pipe excess sludge. The tank 3 for pre-treatment of water has an inlet 7 and a device for removing sediment and sludge (not shown). Vertical cleaning tank 1 time divided by transverse L-shaped partitions 8 and 9 on the bottom 10 and top 11 sections. The baffles 8 and 9 are arranged one above the other and are rigidly attached alternately to the opposite and adjacent walls of the cleaning tank 1. In each section pneumatic aerators 12 and 13 are placed, which serve for dispersion. air in the treated water, overflow pipelines 14 and 15, connected respectively with a tank for preliminary purification of water and a tank for collecting activated sludge. Pneumatic aerators are ceramic filter filters that are sized according to horizontal partitions and are connected to the compressed air line 16 via control valves. A tank 4 for collecting activated sludge is connected to the upper section 11. of the cleaning tank 1 by a pipe 6 for returning excess sludge.

The installation works as follows.

The contaminated water through the inlet 7 fills the tank 3 for pre-purification of water (see Fig. 1 in which heavy undissolved impurities are captured and the water is settled to remove floating oil and oil products. Through the filling pipe 5, water, containing emulsified and dissolved petroleum and petroleum products., it flows by gravity into the lower section 10 of the vertical cleaning tank 1, where it is saturated with air using an aerator 12. In this section, due to the effect of flotation purification, ntrirovanie light impurities at the boundary of water with the air section, the air contained in the cavity.

Continuous removal of the surface layer of water saturated with oil pollution / is carried out with exhaust air trapped by the L-shaped transverse partition 8 through the overflow pipe 14 into the pre-treatment tank 3 according to the airlift principle. Part of the most polluted water returns to installations for settling and recycle flotation treatment.

From the lower section 10, the water containing the dissolved and finely dispersed oil fraction enters the upper section 11 of the cleaning tank 1, where it is subjected to biological purification. Recycling active.

The sludge adapted to this contamination is carried out by transferring it along with the water to be purified through the overflow pipe 15 to the tank 4 to collect the activated sludge and return the regenerated sludge through the pipeline 6 to the biological treatment zone. The geometrical dimensions {of the channel linking the lower 10 and upper 11 sections are chosen such that the vertical component of the water velocity exceeds

the rate of sedimentation of activated sludge, i.e. the value of 0.3-0.5 mm / s. The transfer of the sludge mixture into the tank 4 is carried out by an airlift due to the exhaust air going to aeration through the aerator 13 and captured by a L-shaped transverse partition 9..

Due to the constant saturation of the treated water with oxygen (due to the high recirculation ratio) in the tank 4 for collecting activated sludge, oxygen deficiency is eliminated and normal regeneration of activated sludge is achieved without additional aeration.

Purified water is discharged through tray 2 from the zone of vertical purification tank 1.

To dispose of industrial wastewater from several different class of pollutants at the same time, biodegradation of each of which can occur only in the presence of certain microbiocenosis, it is possible to use multi-stage cleaning with maintaining a certain microbiocenosis in each step (Fig.2).

The installation ensures efficient operation in the wide range of changes in the initial concentration of contaminants. Allows the fullest use of the facility. Due to the timely collection and removal of light impurities, the cleaning time is shortened. In addition, the effect of overflow pipelines on the principle of airlift contributes to the rational use of air and high recirculation of activated sludge.

Claims (2)

1. Installation for the biological purification of oily water, including a vertical cleaning tank divided in height into sections by transverse partitions, overflow pipelines placed in each section, aerators and an activated sludge collection tank with an activated sludge return pipe, which is so that, in order to ensure that II leads Light impurities, partitions have edges bent down and attached alternately to the opposite walls of the container. 2. Installation according to claim 1, wherein it has a capacity for pre-treatment of water, the overflow pipe of the lower section is connected to a capacity for pre-treatment of water, The overflow pipe of the upper section is equipped with a tank for collecting activated sludge, and the return pipe of excess sludge is connected to the upper section. Sources of information taken into account in the examination 1. USSR author's certificate 256658, cl. C 02 C 1/10, 1968. 1B