SU1101414A1 - Apparatus for treating effluents - Google Patents

Abstract

1. INSTALLATION FOR TREATMENT OF WASTE WATERS containing a water intake in the form of a housing with and pipes for collecting and returning untreated water, a circulation pipe with forward and backward branches, a circulation pump installed on the forward branch of the circulation pipeline, flotator, pressure pipeline permanently flow rate, connecting the water intake with the flotation cell, the Isham tank and the tank of purified water, the pipeline with the pump for pumping Ishama and the pipeline with the pump for pumping, purified water, and the control unit of the installation, excl In order to increase the efficiency of using the installation by ensuring operational reliability and continuity of its operation, it is equipped with a pipeline connected to a constant-flow pressure pipe and a circulation pipe installed on the forward branch of the circulation pipe before the circulation pump by the sensor vacuum and also placed on the discharge pipe of a constant flow rate av (L) a automatic shut-off valve controlled by a vacuum sensor through the control unit laziness. 2. Installation under item 1, characterized in that the water intake is provided with a casing located behind the grid with a hole in its lower part, while the water intake grid is installed with an inclination in the direction of the flow of return water. four

Description

The invention relates to combined plants for the treatment of domestic and industrial wastewater and can be used to treat shipboard wastewater that is generated on board a ship. A known installation for sewage treatment on ships, comprising a block for separating solid components from sewage, a pressure tank, a flotation cell, a chemical cleaning unit, an oxidation unit, an ejector unit, an ozone generator, a piping system, and pumps. The coarse cleaning unit contains a coarse filter, a receiving tank and a sludge tank. At the same time, the coarse filter is a rotary grid installed directly under the receiving nozzle of the receiving tank. The sludge tank is located in close proximity to the receiving tank and is associated with it in the area of the rotating grid. The wastewater is drawn by a special centrifugal pump from the ship's faecal tank and is fed to a swivel grid installed in the receiving tank. The large impurities contained in the waste water are trapped by this net, and the water flows into the receiving tank. From the receiving tank, water is fed for further cleaning and disinfection. Large impurities accumulated on the rotary grid are dumped into the sludge container by rotating the grid. Then the grid is returned to its original position. The grid is rotated to the Isham capacitor and returned to its original position manually. This installation provides good quality of cleaning and disinfection of wastewater Cl However, the operation of the installation is possible only with constant monitoring by the staff and applying manual labor. This is due to the fact that it is necessary to constantly monitor the accumulation of large impurities on the rotary grid for preventing its complete clogging and, as a result, sewage into the sludge tank. Cleaning the rotating grid is carried out manually. Centrifugal pump. Feeding untreated sewage from a faecal tank to a receiving tank is often clogged with large impurities contained in the sewage, and is also manually cleaned. Also known is an installation comprising a water intake device, a pressure floater with a scraper mechanism for removing foam, a slurry tank and a purified water tank connected with a flotation cell, a pipeline with a pump for pumping sludge, a pipeline with a pump for pumping purified water, as well as an installation control unit. The water intake device includes a water intake in the form of a housing with a grid and nozzles for — intake and return of untreated water, as well as a circulation pipe with direct and reverse branches connected to said nozzles, and a circulation pump installed on the forward branch of the circulation pipe. pipeline The water intake grid is located perpendicular to its body, i.e. perpendicular to the flow of untreated water drawn from the faecal cistern. To clean the mesh from the retained large impurities, a flushing nozzle is installed, mounted on the nozzle for water intake and connected to the ship's intake water line. A pressure tank is installed between the direct and reverse branches of the circulation pipe. The flotation machine is connected to a pressure tank with a constant flow pressure pipe, which is a calibrated tube. A coagulum container is connected to the pressure pipeline of constant flow through the metering pump. A pipe connecting the flotation unit and the tank of purified water is connected to a tank with a disinfectant reagent through a pump doser. An ejector connected through the air to the sludge tank and the tank of purified water is installed on the reverse leg of the circulation pipe. When the installation is in operation, the circulation pump draws water through the nozzle for water intake from the water intake housing installed in the ship's faecal tank and drives it under excessive pressure along the straight branch of the circulation pipeline to the pressure tank. In this case, large contaminants contained in the wastewater are retained from the water intake. In a pressurized tank, a cos3 .1 gives an excess pressure of p d ka 2-3 atm. Approximately 60% of the water from the pressure tank is returned to the water intake case along the return leg of the circulation pipe. An ejector installed on the return branch of the pressure pipelines enriches the water with air. For this reason, the water in the pressure tank contains a significant amount of dissolved air. Approximately 40% of the water from the pressure tank comes through a constant-flow pressure pipeline to the flotation cell. The conduit is a calibrated tube. With a constant pressure in the pressure tank, the flow of water through the pipeline is also kept constant. On the way, coagulum is introduced into the water. The flotation process is a process of pressure flotation. The resulting sludge in the form of foam is removed by a scraper mechanism into the sludge tank, the purified water enters the tank of purified water. On the way, a disinfecting solution is introduced into it - 2J. However, the operational reliability of a known installation is not high enough. This is explained in the following. During plant operation, large contaminants contained in the waste water are retained by the net. In the initial period of operation of the installation, the reverse flow of water through the return nozzle flushes these contaminants from the grid. However, the grid is gradually becoming dirty. This leads to a decrease in the volume of water entering the pressure tank. Drainage of water from a pressure tank through a constant flow discharge pipe to the float & is constant in volume. This leads to a decrease in the flow of water returning along the return leg of the circulation pipe to the water intake and falling onto the grid. The grid is even more polluted. The volume of water supplied by the circulation pump to the pressure tank is further reduced. The discharge of water from the pressure tank through a constant flow pressure pipeline is kept constant in volume. This further reduces the flow of water, returning 1yce through the return leg of the circulation pipeline, etc. Such a process, if the plant continues to operate, will be irreversible and may lead to 44 failure of the circulation pump. To prevent this, the installation must be stopped and the grid cleaned by supplying water to the water intake from the intake water line from the ship. Only after this installation will be ready to work again. The aim of the invention is to increase the efficiency of use of the installation by ensuring operational reliability and continuity of its operation. The goal is achieved by the fact that a sewage treatment plant containing a water intake in the form of a housing with a net and nozzles for collecting and returning untreated water, a circulation pipe with forward and backward branches, and a circulation pump installed on the right my branch of the circulation pipe, a flotation machine connected to a constant flow pressure pipe with a water intake device behind the circulation pump, a sludge tank and a tank of purified water connected to the flotation cell, t The pipeline with the pump for pumping slurry and the pipeline with the pump for cleaning the treated water, as well as the unit control unit, is equipped with a pipeline connected to the pressure pipeline of a constant flow rate and the circulation pipeline installed on the straight branch of the circulation pipeline before the circulation pump by a sensor a vacuum, as well as an automatic shut-off valve installed on the discharge flow pipe of a constant flow, controlled by a discharge sensor through a control unit. In addition, the water intake grid is installed with an inclination in the direction of the return water flow, the water intake is equipped with a network installed (a casing with a hole in its lower part. With a clean water intake grid, it is circulating, the pump draws water through the water inlet direct branch of the circulating pipeline. In this case, the vacuum in the direct branch of the circulating pipeline before the circulating pump 51 does not exceed the established one, no signal is received from the vacuum sensor and The automatic valve on the pressure piping to supply water to the flotation device is open. In this case, the flow of water moving along the straight leg of the circulation piping reaches the discharge piping of this flow, forks: a smaller part of the flow goes through this the pipeline for cleaning and disinfection directly into the flotation cell, and most of the flow returns through the return branch of the circulation pipeline to the water intake housing, flushing large impurities from the grid, containing EU in the waste water. At the moment when the grid starts to contaminate, an increase in the discharge in the direct branch of the circulation pipe of the wire in front of the circulation pump triggers the vacuum sensor and, accordingly, closes the automatic valve on the constant flow pressure pipe. In this case, the entire flow of water injected circulating at the pump, enters from the direct branch of the circulating pipeline to its reverse branch and returns to the water intake housing. The flow and pressure of water coming from the water return pipe to the water intake grid increases dramatically, which leads to its rapid purification from large impurities that clog it. At the same time, there is no decrease in the volume of water circulating along the contour of the water intake - the circulation pipe, and there is no danger to the circulation pump. Due to all this, the operational reliability of the installation is increased. When cleaning the grid from contaminated backflow streams of water, passing through the free grid cells, are reflected by the end wall of the casing and run onto the outside of the grid at an acute angle. As a result of this contamination, the mesh clogged, I am impacted from two sides; backflow jets that act on contaminants from inside the hull tend to tear them away from the grid, and reverse flow jets reflected on the grid with a casing remove the contaminants from the net. Such an impact on the soils that clog the grid dramatically increases the efficiency of the cleaning of the grid with a reverse flow of water, which increases the operational reliability of the installation. In addition, large soils contained in wastewater are usually unevenly distributed throughout the volume of liquid: some of the pollution floats and is in the upper layer of the wastewater, and some of the pollution falls to the bottom of the fecal tank. At the same time, the average part of the effluent contains a smaller number of large impurities. The water intake casing, which is open at the bottom, allows water to be taken from the middle part of the effluent in the fecal tank, thereby increasing the reliability of the grid and reducing the likelihood of clogging. FIG. 1 shows a plant for wastewater treatment; Fig.2 water intake, longitudinal section. The installation includes a water intake device 1, including a water intake 2, made in the form of a housing 3 with a grid 4, a pipe 5 for the intake and a pipe 6 for returning the raw water, as well as the circulation pipe 7. The circulation pipe 7 has a forward 8 and a reverse 9 branches connected to the nozzles 5 and 6 of the water intake 2, respectively. On the straight branch 8 of the circulation piping 7 there is a circulating pump 10. A rotary pump 11 and a manual valve 12 are installed in front of the circulating pump 10 and a manual valve 13 on the return branch 9 of the circulating pipeline 7. The grid 4 is tilted in the direction of return water flow . The grid 4 is covered with a casing 14 mounted on the housing 3. The casing 14 covers the grid 4 from the front and from the sides. Access of water in the grid 4 is possible only from below. If we consider the position of the casing 14 relative to the grid 4 along the return water flow, then it is located behind the grid 4. The housing 3 of the water intake 2, the water inlet nozzle 5 and the water return nozzle 6 are mounted on the flange 15, with which the water intake 2 is mounted on the faecal tank 16 . For 771

The washing of the net 4 with seawater is provided by a branch pipe 17 connected to the ship intake water system. The circulating pipeline cb is connected to a constant-pressure discharge pipe 18 with: an electrochemical flotation device 19. The pipeline 18 has an automatic valve 20 and an orifice plate 21, which ensures the constant flow of water through the pipeline 18. The flotation device 19 has a pneumatic device for foam removal. The flotation device 19 is connected by a pipe 22 with a tank 23 of purified water. An automatic valve 24 is provided on the pipe 22. The flotation device 19 is also connected to a pipe 25 with a slurry tank 26. The pipeline 27 with pump 28 serves to remove the purified water from the tank 23; A pipe 29 with a pump 30 serves to remove the sludge from the sludge tank 26.

For pumping out the sludge, there is a pipeline 31 to feed the sludge into the incinerator and the pipeline 32 to return the sludge to the faecal tank 16. Manual valves 33 and 34 are installed on these pipelines. The installation is vented by a fan 35. The installation is switched on by a float sensor 36 of the upper level , and. off - from the sensor 37 of the lower level. The installation is fully automated and controlled by the installation control unit 38.

The installation works as follows.

When the unit is turned on, the circulation pump 10 draws water from the casing 3 of the water intake 2 through the pipe 5 and pumps it into the straight branch 8 of the circulation pipe 7. The grid 4 retains large contaminants in the wastewater. Casing 14 makes it difficult to access the grid of 4 large soils that are suspended in a thick layer of sewage. With a normal flow of water into the casing 3 of the water intake 2, the vacuum in the forward branch 8 of the circulation pipe 7 before the circulation pump 10 does not exceed the set, no signal from the vacuum sensor 11 goes to the control unit, and the automatic valve 20 on the discharge pipe

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18 constant flow open. The flow of water moving along the straight leg 8 of the circulation conduit 7, reaching the pressure conduit 18, splits. A smaller part of the water flow (about 30%) goes to the pressure pipe 18, and a large part (about 70%) goes to the return branch 9 of the circulating pipe 7. This separation of the flow is provided by the orifice plate 21 installed in the pressure pipe 18. Cleaned water flows through this pipeline into the flotation cell 19, where its final cleaning and disinfection takes place. The sludge enters the flotation unit 19 through conduit 25 into the sludge tank 26. Purified water enters the flotation unit 19 through conduit 22 into the purified water tank 23. From the reverse branch .9 of the circulation pipeline 7, water flows into the body 3 of the water intake 2 and flushes grids 4 large impurities retained by it.

At the time of the start of the pollution of the grid 4, an increase in the vacuum in the straight branch 8 of the circulation pipe 7 in front of the pump 10 occurs, which causes the sensor to operate 11 times

cutting The control unit 38 instructs to close the automatic valve 20 on the pressure pipe 18. After the valve 20 is closed, all the water flow pumped by the circulation pump 10 comes from the forward branch 8 of the circulation pipeline 7 to its reverse branch 9 and returns to the water intake body 2 . The flow of water coming from the nozzle b for returning water to the grid 4. water intake, rarely increases, which leads to a rapid purification from impurities clogging it. This process is intensified by the presence of the casing 14 and the inclination of the grid 4 in the direction of flow of the return water. The return water flow jets, having passed through the free cells of the grid 4, are reflected by the end wall of the casing 14 and run onto the outer side of the grid 4. at an acute angle. As a result of this contamination, clogged grid 4 is affected from two sides: backflow jets affecting the contamination from inside the housing 3 tend to tear them off from grid 4, and

return flow of water reflected on mesh 4 by casing 14 - reduce contamination from mesh 4. Such an effect on soils clogged mesh 4 dramatically increases the cleaning efficiency of mesh 4 by reverse flow of water. As a result of intensive cleaning of mesh 4, the water flow from the faecal tank 16 to the water intake 2 increases and the vacuum before the circulation pump 10 decreases, causing the vacuum sensor 11 to re-activate. The control unit 38 vanishes. signal “to open the automatic valve 20 on the pressure pipe 18 and the water to be purified continues to flow into the flotation cell 19.

The technical advantage of the proposed installation is a higher operational reliability

The expected annual economic effect will amount to 130,000 rubles. on one installation.

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Claims (2)

1. SEWAGE TREATMENT PLANT containing a water intake in the form of a housing with a net and intake pipes for untreated water, a circulation pipe with direct and reverse branches, a circulation pump installed on the straight branch of the circulation pipe, a flotator, a constant pressure discharge pipe connecting the water intake with flotator, sludge tank and purified water tank, piping with a pump for pumping out sludge and a pipeline with a pump for pumping purified water, as well as the unit control unit, ex Moreover, in order to increase the efficiency of the installation by ensuring operational reliability and continuity of its operation, it is equipped with a pipeline connected to a constant flow pressure pipe and a circulation pipe installed on a straight branch of the circulation pipe in front of the circulation pump with a vacuum sensor, as well as an automatic shut-off valve located on the constant flow pressure pipe, controlled by a vacuum sensor through the control unit. 2. Installation according to claim 1, characterized in that the water intake is provided with a casing located behind the grid with an opening in its lower part, while the water intake grid is installed with an inclination in the direction of the return water flow. SU „., 1101414