RU2205924C2 - Station to purify surface runs-off - Google Patents

Abstract

FIELD: conservation of water resources, prevention of fouling of water objects by surface heavy-shower runs- off, in particular. SUBSTANCE: station to purify surface runs-off includes drain collector linked to intake-distribution chamber, unit of primary treatment of water from course- dispersive particles and oil products and unit of additional treatment of water with filters based on filtering load fitted with pipe-lines supplying water for purification and discharging purified water and system to flush filtering load. Unit of primary treatment has thickener, at least one hydrocyclone, separator connected in series and is linked to unit of additional treatment of water by buffer vessel equipped with system of hydraulic flushing of sediment in the form of perforated tube which is discharge tube of separator and is laid around the edges of bottom of buffer vessel. Unit of additional treatment is supplemented with multicyclone installed in front of filters which presents three vessels with filtering loads of gravel-sand, zeolite, shungite correspondingly installed in series. System to flush filtering load is provided with vessel of flushing fluid, vessel collecting solution after flushing of filtering load, filter and pump. Station also includes system for removal of thickened phase presented by Nutsche filter communicating with thickener and carrying fixture to unload dewatered sediment. EFFECT: increased efficiency of purification of surface runs-off when they are conveyed to water object to protect environment. 4 cl, 1 dwg

Description

 The invention relates to the protection of water, in particular, to the prevention of pollution of water bodies by surface storm water.

 A known wastewater treatment plant (RF patent 2094395, MKI C 02 F 9/00, priority July 16, 1996), including settling chambers, aeration tank, activated sludge recirculation system, system for removing purified water and sludge. The disadvantage of the design is that it does not allow to achieve the necessary degree of wastewater treatment to discharge them into water bodies.

 The closest technical solution to the proposed technical essence and the achieved result is a surface wastewater treatment plant (USSR author's certificate 1390320, MKI E 03 F 5/10, priority date 30.01.86), including a drainage collector connected to a receiving and distribution chamber, a unit for the primary treatment of water from coarse particles and oil products and a post-treatment unit with filters based on a filter load, equipped with pipelines for supplying water for purification and removal of purified water, a filter washing system th boot. However, the proposed rainwater treatment system does not provide the required quality of wastewater discharge, presented when these waters are discharged into a water body.

 An object of the invention is to increase the efficiency of surface water treatment when discharging them into water bodies in order to protect the environment.

 The stated technical problem is solved due to the fact that in the surface wastewater treatment plant, including a drain collector connected to the receiving and distribution chamber, a unit for primary treatment of water from coarse particles and oil products and a post-treatment unit with filters based on a filter charge, equipped with water supply pipelines for purification and removal of purified water, a washing system of the filter load, the primary water treatment unit contains a sequentially located thickener, at least one hyd the cyclone, the separator and is connected to the after-treatment unit with a buffer tank equipped with a sludge washout system in the form of a perforated pipe, which is a drain pipe of the separator and laid along the perimeter of the bottom of the buffer tank, the after-treatment unit additionally contains a multi-cyclone installed in front of the filters, which are three consecutive containers with filter loads gravel sand, zeolite, shungite, respectively, the washing system of the filter load is equipped with a washing solution tank, a collecting tank p after washing the filter load with a filter and a pump, while the station further includes a condensed phase removal system represented by a suction filter in communication with the thickener and having a device for unloading the dehydrated sludge. Moreover, the container with filtering loading gravel-sand has a layer-by-layer type of loading: three gravel - a sublayer, an unloading, a covering layer 200 mm thick and two sand layers 400 mm thick. In the washing system of the filter load, a volume-porous electrostatic precipitator is used. A bioreactor for treating the dehydrated sludge is included in the condensed phase removal system. As a washing solution, a solution of sodium chloride is used.

 The drawing shows a schematic diagram of a surface wastewater treatment plant.

 The surface wastewater treatment plant comprises a drainage collector 1, a receiving and distribution chamber 2, a primary water treatment unit for coarse particles and oil products, containing a sequentially arranged thickener 3, at least one hydrocyclone 4, a separator 5, a buffer tank 6; a post-treatment unit including a multicyclone 7, filters with gravel-sand charges 8, zeolite 9, shungite 10, respectively, the capacity of treated effluents 11, pipelines for supplying effluents for purification and removal of purified water 12. The condensed phase removal system is represented by a suction filter 13 having a device (pump) 19 for unloading the dehydrated sludge, for processing of which the bioreactor 14 is included in the system, with slurry pipes 15 suitable for the suction filter. The washing system of the filter load consists of a washing solution tank 16, a collecting tank target after washing the filter media 17, porous volume electrostatic precipitator 18, a pump 20 for supplying washing solution for washing the filter, after flushing solution pipeline filter media 21. Retraction of the filtrate from a suction filter is carried through conduit 22.

 Station surface water treatment works as follows. Surface storm runoff from the catchment area, flowing down the surface through the gutter collector 1, enters the receiving and distribution chamber 2, where garbage is collected on the trash racks, from where the surface runoff passes through all the cleaning stages sequentially through pipeline 12, and first it enters the primary water treatment unit , in which the flow is first fed to a vertical thickener 3. Suspended substances are concentrated by the action of centrifugal force at the walls of the thickener and flow into a sludge funnel, otku and for slurry pipe 15 are sent to the suction filter for dewatering.

 The use of a vertical thickener in the scheme ensures the use of a centrifugal sediment instead of gravitational sedimentation, which creates conditions for the coalescence of finely dispersed suspensions, emptying immediately after the interruption of stormwater, and the possibility of receiving subsequent ones in the event of repeated rainfall. The past stage of purification, the water from the vertical thickener 3 is pumped through a pipeline 12 to a hydrocyclone 4, where sand and mineral particles with a diameter of up to 0.02 mm are separated from the stormwater runoff. The clarified water through the pipeline 12 then under residual pressure enters the separator 5, where coarse and finely dispersed (drop) oil products are separated, as well as suspended fine particles up to 0.005 mm in size. Caught petroleum products are unloaded in special containers.

 The wastewater (purified water) after the separator 5 is sent to the second stage of purification, to the after-treatment unit through a buffer tank 6, designed to accumulate pre-treated effluents and equalize the hydrodynamic load. The buffer tank 6 is equipped with a water wash system in the form of a perforated pipe 5, which is a separator drain pipe laid along the perimeter of the bottom of the tank 6. The use of the buffer tank 6 is due to the fact that, when the cleaning process is completely automated, it is necessary to stabilize the hydrodynamic regime to facilitate cleaning conditions on multicyclones 7 and filters 8-9, an additional opportunity is created for the purification of already clarified water by gravitational sedimentation, which took place in the buffer tank 6. From the buffer tank 6 clean boiled water is fed into the post-treatment unit to multicyclone 7, wherein the flow completely cleaned of fine sediment that provides operation gravel-sand filter 8, which further receives a stream for long periods without regeneration of the filter loading. Gravel-sand filter 8 has a layer-by-layer type of loading: three gravel - sublayer, discharge and cover layers 200 mm thick and two sand layers 400 mm thick. Such an optimal loading method is adopted to reduce hydrodynamic drag. The water stream for filtration is served from below. From above comes a stream of effluents, finally cleaned of suspended solids and oil products, which is then sent to the second stage of filtration - a filter with a filter charge zeolite 9 having a mesoporous structure. Here, wastewater is purified at the ionic level from fine gel-like substances.

 The third stage of filtration is carried out on a filter with a filter charge of shungite 10, which has a high selectivity to carbon-containing ions, has bactericidal properties. This filter conducts deep ionic treatment of effluents from soluble contaminants. Pure water after filtration in the filter 10 under residual pressure is collected in a clean water tank 11, from where it overflows into the overflow well and then enters the collector of the city drain. It is possible to supply water from the clean water tank 11 to flush the filter media. The thickened precipitate from hydrocyclone 4, separator 5, multicyclone 7 through the sludge pipe 15 enters the working surface of the suction filter 13, where it is dehydrated and fed to the bioreactor 14 for biological degradation by means of a discharge device 19, and the filtrate is fed to the process head through a pipe 22 , to a thickener 3. A system for washing filter loads is provided in the installation to restore the properties of the load as it becomes dirty.

 The prepared sodium chloride solution from the washing solution tank 16 is fed from above to the filters 8, 9, 10, passing through the charge of which it is enriched with the accumulated impurities from the washing of wastewater, and through a pipe 21 it is supplied to the container 17 collecting the solution after washing the filters 8, 9, 10 The solution pipeline after washing the filters 21 communicates with the thickener 3, through which the water contaminated after washing the filters is returned to the cleaning. A volume-porous electrostatic precipitator 18 is included in the system for processing the solution from the reservoir 17 before it is supplied to the washing water reservoir 16, from where water is used to rinse the filter media. Flushing the filter media takes place in a closed system.

 The proposed station provides the necessary effect of the treatment of surface effluents when they enter water bodies. The pollution content in them: for suspended solids - 1.2-3 mg / l, for petroleum products - 0.05 mg / l.

Claims (5)

 1. A surface wastewater treatment plant, including a drainage collector connected to a reception and distribution chamber, a primary water treatment unit for coarse particles and oil products, and a post-treatment unit with filters based on a filter charge, equipped with pipelines for supplying water for treatment and removal of purified water, a washing system filter loading, characterized in that the primary water treatment unit contains a sequentially arranged thickener, at least one hydrocyclone, a separator and is connected to the unit tertiary treatment with a buffer tank equipped with a sludge washout system in the form of a perforated pipe, which is a drain pipe of the separator, and laid along the perimeter of the bottom of the buffer tank, the tertiary treatment unit additionally contains a multicyclone installed in front of filters representing three tanks in series with filtering gravel-sand, zeolite, schungite, respectively, the washing system of the filter load is equipped with a washing solution capacity, a capacity collecting solution after washing the filter load and, with a filter and a pump, the station further includes a condensed phase removal system represented by a suction filter in communication with the thickener and having a device for unloading the dehydrated sludge.  2. The station according to claim 1, characterized in that the container with a filter loading gravel-sand has a layer-by-layer type of loading: three gravel - a sublayer, an unloading, coating layer 200 mm thick and two sand layers 400 mm thick.  3. A station according to any one of claims 1 or 2, characterized in that a volume-porous electrostatic precipitator is used in the washing system of the filter load.  4. A station according to any one of claims 1 to 3, characterized in that a bioreactor for treating the dehydrated sludge is included in the condensed phase removal system.  5. The station according to any one of claims 1 to 4, characterized in that a solution of sodium chloride is used as a washing solution.