CN110092531A - A kind of multifunctional assembled Tailwater Depth denitrogenation dephosphorizing artificial wet land system - Google Patents

Abstract

The invention discloses a combined multi-functional artificial wetland system for deep denitrification and phosphorus removal of tail water. The system includes a hydrolysis acidification area (1), a biomass filler placement area (2), a denitrification wet area (3), a nitrification wet area (4), denitrification wet area (5), enhanced phosphorus removal area (6). The tail water enters the hydrolysis acidification area (1) and contacts with the bio-film composite filler to effectively utilize the nitrogen and phosphorus elements of the tail water. The tail water enters the biomass filler placement area (2) through the diversion tank. Nitrification provides favorable conditions. The denitrification wet areas (3) and (5) adopt closed top covers, which can provide anoxic environment for microorganisms. The high-calcium fly ash ceramsite and sulfur-iron composite filler in the enhanced phosphorus removal zone (6) can effectively remove phosphorus. This system can effectively solve the contradiction between tail water dephosphorization and denitrification on the demand for carbon source. It is not easy to block, the effluent quality is good, and the investment is small. With the planting of aquatic plants, it can also achieve the effect of beautifying the landscape.

Description

A combined multi-functional tail water deep nitrogen and phosphorus removal artificial wetland system

technical field

The invention relates to the technical field of sewage treatment, in particular to a combined multifunctional artificial wetland system for deep denitrification and dephosphorization of tail water.

Background technique

At present, the effluent water quality of my country's sewage treatment plants generally implements the first-class A or B standard in the "Pollutant Discharge Standards for Urban Sewage Treatment Plants" (GB18918-2002). However, due to the unreasonable sewage treatment process and treatment equipment in many urban sewage plants, the efficiency of sewage treatment is low, the energy consumption is high, and a large amount of tail water from sewage plants is directly discharged to receiving water bodies. Although most of the tail water of the sewage treatment plant can meet the discharge standard, it still has a lot of pollutants. Taking the third class water on the surface as an example, the concentration of the effluent from the sewage treatment plant is 3-3% of the "Environmental Quality Standard for Surface Water" (GB3838-2002). 15 times (COD is 3 times; total nitrogen is 15 times), there is a big gap between the two, and direct discharge will bring a series of problems. The tail water of urban sewage treatment plants has a large amount of water, low concentration of organic matter and complex components, and high content of nitrogen and phosphorus, so it is difficult to carry out advanced treatment.

Constructed wetland technology is an ecological system that is artificially constructed and controlled to operate. Sewage and sludge are distributed to the artificially constructed wetland in a controlled manner. In the process of flowing sewage and sludge in a certain direction, soil and artificial media are used to The physical, chemical and biological triple synergy of plants, microorganisms absorb organic matter, nitrogen, phosphorus and other pollutants in sewage. The treatment of tail water by constructed wetland technology has the characteristics of low investment and maintenance costs and small secondary pollution, which meets the needs of modern water treatment development. However, the treatment efficiency of a single constructed wetland is not high, the treatment effect is unstable, and is greatly affected by temperature. The organic content of pollutants in the tail water is relatively small, and the growth of microorganisms requires the use of carbon sources, so the constructed wetland as a tail water treatment unit often cannot fully exert its treatment capacity.

The Chinese invention patent with the application number 201510680367.7 discloses a composite gravel bed for constructed wetlands. The composite gravel bed of the invention is composed of a growth matrix layer and a filler layer. The removal rate of COD is higher than 50%, and the removal rate of total nitrogen and phosphorus is also average. It is more than 60%, but when the hydraulic load and impact load of the influent are large, a single composite gravel bed cannot meet the water quality requirements of the effluent.

The Chinese invention patent with the application number 201610419636.9 discloses a combined artificial subsurface flow wetland treatment system for enhanced nitrogen and phosphorus removal. This invention removes suspended pollutants in sewage through screens, and uses microorganisms, plants, and matrix adsorption to remove nitrogen and phosphorus. , but when the organic matter in the sewage influent is insufficient, it is difficult to carry out denitrification and denitrification, resulting in the deterioration of the effluent water quality.

Therefore, aiming at the deficiencies of existing technologies, a system integrating tail water pretreatment and combined wetland denitrification and phosphorus removal is developed, which can save energy and reduce consumption, and combine with landscape, which can not only meet the current tail water treatment requirements, but also meet the Wetland treatment system for future tail water treatment needs.

Contents of the invention

Technical problem: The purpose of this invention is to provide a combined multifunctional tail water deep denitrification and phosphorus removal artificial wetland system, through the mutual combination between areas to treat the tail water, so that it can further meet the "Environmental Quality Standards for Surface Water" ( GB3838-2002) to meet the relevant requirements of future water treatment trends.

To achieve the above object, the present invention provides the following technical solutions:

A combined multifunctional tail water deep nitrogen and phosphorus removal artificial wetland system, the tail water passes through independent pretreatment functional areas and deep nitrogen and phosphorus removal treatment functional areas. The tail water is treated in combination between the functional areas, and the tail water in each functional area overflows through the partition and enters the next functional area.

According to the above scheme, the tail water sequentially passes through the pretreatment functional zone hydrolysis acidification zone (1) and the biomass filler placement zone (2).

According to the above scheme, in the hydrolytic acidification zone (1), the unit diameter is 150mm and the length is 0.9m, and the double-circle polypropylene biofilm composite filler is vertically arranged, and the tail water enters through the diversion groove at the bottom of the hydrolysis acidification zone (1). The biomass filler placement area (2), the biomass filler placement area (2) is horizontally provided with a partition with a size of 25cm*25cm, the partition is opened with a diameter of 3cm round holes every 3cm, and the partition is placed on the partition. The biomass filler wrapped by amide fiber releases organic carbon source for the use of microorganisms, which is conducive to the denitrification of tail water.

According to the above plan, the system adopts multi-point water intake, and the tail water inlet pipe respectively passes through the water inlet pipe (7) of the hydrolysis acidification area, the water inlet pipe (8) of the biomass filler placement area, the water inlet pipe (9) of the denitrification wet area, and the water inlet pipe of the denitrification area. The water inlet pipe (10) in the wet area is sequentially connected to the hydrolytic acidification area (1), the biomass filler placement area (2), the denitrification wet area (3), and the denitrification wet area (5). Each water inlet is connected with a stainless steel thread The gate valve is connected to adjust the water flow so that the flow of each water inlet is Q/4. Among them, baffle plates are set in the denitrification wet area (3), nitrification wet area (4), and denitrification wet area (5), so that the tail water can overflow into the next area, and the tail water enters the denitrification wet area through the overflow pipe. area (3), nitrification wet area (4), denitrification wet area (5), enhanced phosphorus removal area (6), and finally the tail water is discharged through the outlet pipe (11) provided at the bottom of the enhanced phosphorus removal area (6).

According to the above scheme, when the tail water passes through the denitrification wet area (3) and the denitrification wet area (5), a removable PVC material top cover (12) with a size of 25cm*25cm is embedded on the top of the area, ( 13).

According to the above scheme, when the tail water passes through the wet denitrification area (3), plastic ball composite fillers with a height of 70 cm and a particle size of 25 mm made of polypropylene are set in the area.

According to the above plan, when the tail water passes through the nitrification wet area (4) and the enhanced phosphorus removal area (6), the first packing area, the second packing area, and the third packing area are sequentially formed from bottom to top inside the area through natural settlement. District, the nitrification wet area (4) is respectively filled with a thickness of 30cm with a particle diameter of 2-5mm gravel filler layer, a thickness of 20cm with a particle diameter of 1-3mm modified zeolite filler layer and a thickness of 20cm with a particle diameter of 1-3mm 2mm fine sand packing layer, the enhanced phosphorus removal zone (6) is filled with a gravel packing layer with a thickness of 30cm and a particle size of 2-5mm, and a 20cm-thick high-calcium fly ash ceramsite and sulfur iron with a particle size of 1-3mm Composite filler and fine sand filler layer with a thickness of 20cm and a particle size of 1-2mm.

According to the above scheme, when the tail water passes through the denitrification wet area (5), a polypropylene moving bed biological fluidized bed filler with a height of 70 cm and a particle size of 2 cm is set in the area.

According to the above scheme, when the tail water passes through the nitrification wet area (4) and the enhanced phosphorus removal area (6), planting in the area has a high removal effect on pollutants such as nitrogen and phosphorus, is easy to harvest, and can be used as Biomass carbon source can release wetland plants with higher COD and lower total nitrogen.

According to the above scheme, when the tail water passes through the biomass filler placement area (2), the biomass filler wrapped by polyamide fiber in the area can be planted by the nitrification wet area (4) and the enhanced phosphorus removal area (6). Plants are harvested.

Beneficial effect: the present invention has following characteristics:

(1) The system can ensure the effective further removal of nitrogen, phosphorus and other pollutants in the tail water.

(2) The system can make the tail water pass through the biomass filler placement area (2), increase the carbon-nitrogen ratio of the tail water, and provide carbon source for microbial denitrification.

(3) In the hydrolytic acidification zone (1), the bio-film composite filler of the system can effectively cut air bubbles, improve the transfer rate and utilization rate of oxygen, and enhance the nitrogen and phosphorus removal capacity of tail water.

(4) In the enhanced phosphorus removal zone (6) of the system, the filler has a strong removal effect on phosphorus, which further improves the quality of the effluent.

Description of drawings

The present invention will be further described below in conjunction with the accompanying drawings.

This figure is a schematic diagram of a combined multi-functional tail water deep nitrogen and phosphorus removal constructed wetland system.

Among them are: hydrolytic acidification area (1), biomass filler placement area (2), denitrification wet area (3), nitrification wet area (4), denitrification wet area (5), enhanced phosphorus removal area (6), Water inlet pipe for hydrolysis acidification area (7), water inlet pipe for biomass filler placement area (8), water inlet pipe for denitrification wet area (9), water inlet pipe for denitrification wet area (10), water outlet pipe (11), denitrification wet area The top cover (12), the top cover (13) of the denitrification wet area.

Detailed ways

The invention is a combined multifunctional tail water deep denitrification and phosphorus removal artificial wetland system. The tail water passes through the hydrolysis and acidification area (1), the biomass filler placement area (2), the denitrification wet area (3), and the nitrification wet area in sequence. Area (4), denitrification wet area (5), enhanced phosphorus removal area (6) for advanced treatment. The tail water inlet pipe respectively passes through the water inlet pipe (7) of the hydrolysis acidification area, the water inlet pipe (8) of the biomass filler placement area, the water inlet pipe (9) of the denitrification wet area, and the water inlet pipe (10) of the denitrification wet area respectively enters the hydrolysis acidification area (1), biomass filler placement area (2), denitrification wet area (3), denitrification wet area (5), the influent flow rate is Q/4. The tail water enters the biomass filler placement area (2) through the diversion groove at the bottom of the hydrolysis acidification area (1), and baffles are installed in the denitrification wet area (3), nitrification wet area (4), and denitrification wet area (5) , so that the tail water can overflow into the next area, and the tail water enters the denitrification wet area (3), the nitrification wet area (4), the denitrification wet area (5), and the enhanced phosphorus removal area (6) through the overflow pipe. Finally, the tail water is discharged through the outlet pipe (11) provided at the bottom of the enhanced phosphorus removal zone (6).

The tail water enters the hydrolysis and acidification zone (1) and fully contacts with the biofilm-hanging composite filler with a diameter of 150mm and a length of 0.9m. The composite filler can not only hang a membrane, but also effectively cut air bubbles, improve the transfer rate and utilization rate of oxygen, The water-air biofilm can be fully exchanged, and the organic matter in the water can be efficiently treated. At the same time, the membrane-hanging microorganisms can effectively use the nitrogen and phosphorus elements of the tail water as their own nutrients. The tail water enters the biomass filler placement area (2) through the bottom diversion tank. The biomass filler can release a large amount of organic matter to increase the carbon-nitrogen ratio of the tail water, improve the biodegradability of the tail water, and provide favorable conditions for subsequent denitrification and denitrification. The tail water passes through the denitrification wet area (3) with a height of 70cm and a diameter of 25mm made of polypropylene plastic balls to perform biological denitrification under anaerobic conditions. The tail water enters the nitrification wet area (4) by way of overflow, and is filled with a gravel packing layer with a height of 30 cm, a modified zeolite packing layer with a height of 20 cm, and a fine sand packing layer with a height of 20 cm, during which nitrification takes place. The tail water enters the denitrification wet area (5) by way of overflow, passes through the polypropylene moving bed biofluidized bed filler with a height of 70 cm and a diameter of 2 cm, and performs nitrification and denitrification reaction under alternating conditions of anoxic and aerobic. The tail water enters the enhanced dephosphorization zone (6) through overflow, and removes organic matter in the water under aerobic conditions. At the same time, through the enhanced dephosphorization zone (6) filled with high-calcium fly ash ceramsite and sulfur-iron composite filler, Phosphorus-containing pollutants are removed to further improve the quality of tail water. Finally, the purified tail water is discharged from the outlet pipe 11.

Wetland plants such as calamus, windmill grass, water hyacinth, rush grass, water onion and the like can be planted in the nitrification wet area (4) and the enhanced phosphorus removal area (6). The biomass filler wrapped by polyamide fibers in the biomass filler placement area 2 can be harvested from the wetland plants planted in the nitrification wet area 4 and the enhanced phosphorus removal area 6 .

Claims (4)

1. A combined multifunctional tail water deep denitrification and phosphorus removal artificial wetland system, characterized in that the system passes the tail water through the hydrolysis acidification area (1), and the biomass filler placement area (2) increases the carbon and nitrogen of the tail water Ratio, improve the biodegradability of tail water, tail water through denitrification wet area (3), nitrification wet area (4), denitrification wet area (5), enhanced phosphorus removal area (6) for a series of denitrification and removal Phosphorus improves the quality of effluent water. 2. hydrolytic acidification zone (1) according to claim 1, is characterized in that, be 150mm by the unit diameter that is vertically arranged in the said zone, the double-circle polypropylene biofilm composite packing that length is 0.9m. 3. according to the described biomass filler placing area (2) of claim 1, it is characterized in that, in the described area, horizontally set up the partition plate with the hole that size is 25cm*25cm, every 3cm is opened on the partition plate and is 3cm circular hole with diameter , by placing the biomass filler wrapped by polyamide fibers on the separator, the organic carbon source is released for use by microorganisms. 4. According to claim 1, the system adopts multi-point water intake, which is characterized in that the water inlet is connected to the hydrolysis acidification area (1), the biomass filler placement area (2), the denitrification wet area (3), and the denitrification wet area (3). In the nitrifying wet area (5), each water inlet is connected with a stainless steel threaded gate valve to adjust the water flow, so that the flow of each water inlet is Q/4. The wet denitrification area (3) and the wet denitrification area (5) are all embedded with removable PVC material top covers (12) and (13) with a size of 25cm*25cm on the top of the area, which is conducive to the formation of an anoxic environment .