WO2004028982A1

WO2004028982A1 - A method for treating wastewater

Info

Publication number: WO2004028982A1
Application number: PCT/CN2002/000691
Authority: WO
Inventors: Kunyuan Song; Fang Yan
Original assignee: Shanghai Gi Biotechnology Engineering Co., Ltd.
Priority date: 2002-09-27
Filing date: 2002-09-27
Publication date: 2004-04-08
Also published as: CN1305787C; AU2002338138A1; CN1668536A

Abstract

In a wastewater treatment method wherein wastewater is subjected to two-stage treatment, firstly conducts a primary treatment by a solid-liquid separation device which separates the solid from wastewater, and then the separated water is further subjected to a secondary treatment which combines the Best-Microorganism-System non-sludge biological treatment with the hydroxyl chemical oxidation treatment. During this process, there is no odour and sludge which are produced in the conventional wastewater treatment process.

Description

Sewage place «¾¾ Technical Field

The invention relates to a sewage treatment method, in particular to a comprehensive sewage treatment method for treating urban domestic sewage and industrial organic wastewater by using a combination of BMS bacteria-free sludge biological sewage treatment technology and HYDR0X device sewage physicochemical treatment technology. Background technique

Municipal wastewater is usually treated by a secondary treatment system, which is mainly biological treatment. Commonly used methods include activated sludge treatment systems (conventional activated sludge method, AO method, AB method, oxidation ditch method, etc.), biofilm treatment systems, stabilization ponds, and land treatment systems. Urban wastewater reuse treatment systems generally use physical, chemical or biological methods to remove nitrogen after secondary treatment systems of urban wastewater; chemical or biological methods to remove phosphorus; ozone or activated carbon adsorption to remove trace organic matter; ozone oxidation or chlorination method Pathogens and viruses. After further treatment, the effluent reaches the reuse standard. With the conventional secondary treatment system and the urban wastewater reuse treatment system, the main problems are as follows: ① There is an abnormal odor in the sewage and sludge treatment process, and the operating environment is poor in sanitation. ② Operation management is complicated, and abnormal phenomena such as sludge swelling or sludge clogging are prone to occur during operation. ③ A surplus activated sludge treatment system is required, and the system investment and operating costs are high. ④ The treatment effect is average and the area is large. For high-concentration industrial organic wastewater, especially high-concentration organic wastewater with poor biochemical properties, conventional treatment methods include coagulation, A / O biochemical treatment, membrane separation, extraction, and incineration. The common problems are: To meet emission requirements, investment costs and operating costs are high and extremely uneconomical. The investment costs and operating costs are in a relatively economic range, the treatment is difficult, the treatment efficiency is low, and it is difficult to meet the emission standards. Summary of the Invention

The purpose of the present invention is to provide a system with a high degree of automation, simple management, small floor area, no need to set up a surplus sludge treatment device, low investment and operating costs, high processing efficiency, and particularly suitable for poor biodegradability, high COD, and suspension Comprehensive sewage treatment method for low-level organic industrial wastewater.

The purpose of the present invention is achieved as follows: A comprehensive sewage treatment method includes primary treatment and secondary treatment. It is characterized in that the first-stage treatment adopts a solid-phase high-efficiency loading device, and the second-stage treatment is a method for treating BMS bacteria-free sludge biological wastewater treatment technology (referred to as BMS) and mechanical energy to generate hydroxyl radicals OH-chemical oxidation pollutants.

Confirm this Combination of physical and chemical processing technology (referred to as HYDROX). The sewage treatment process is as follows: the sewage first enters the solid-phase high-efficiency loading device, intercepts the impurities and enters the BMS treatment stage, and finally the water is treated by HYDROX. BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram of a BMS system of the present invention.

Figure 2 shows the removal efficiency of various COD sewage by the BMS system of the present invention. detailed description

The solid-state material high-efficiency load-blocking device is a gravity continuous conveyor belt filter. The sewage first passes through the gravity continuous conveyor belt filter. The sewage contains a large number of large particles of suspended matter and floating matter, and part of the suspended matter (SS) is trapped. After being collected by the solid phase automatic collection device, it will be shipped out. After filtering and intercepting the sewage, the gravity flows by itself into the four compartments of the BMS biological conditioning tank. The four compartments are three-phase fluidized biological reaction tanks. The biological oxidation tank is equipped with a variety of BMS bacteria, fillers and suspended biological growth devices and high-efficiency micro-aeration tubes.

The processing steps are:

a. Fermentation tank: The filtered and intercepted sewage enters the fermentation tank, and the cultured multi-flora microorganisms are used to reduce BOD and COD in the water;

b. Decomposition tank: The effluent from the fermentation tank enters the decomposition tank, and the BMS multi-microbial flora is used to decompose the fermentation material and general harmful bacteria;

c. Digestion tank: The effluent from the decomposition tank enters the digestion tank. By adjusting and cultivating a large number of cocci in the BMS multi-organism microorganisms, it digests and digests various decay compounds and bacilli;

d. Outflow pond: After the water from the digestion tank enters the outflow tank, it is further aerated by biochemical treatment and then flows into the middle tank by gravity. The tank is equipped with a water level alarm device and an automatic control system. The processing steps are as follows: the water level is lower than the minimum level, the HYDROX working pump is self-closing, and the pump is automatically started above the set water level; the intermediate tank water is pressurized by the HYDROX working pump, the fluid is decelerated, and then enters the water tank, and further aerated biochemical treatment After gravity flows into the middle pool. The water level alarm device and automatic control system are set in the pool. The processing steps are: The water level is lower than the minimum level, the HYDROX working pump is automatically closed, and the pump is automatically started when the water level is higher than the set water level. After the water from the intermediate pool is pressurized and decelerated by the HYDROX working pump, Entering the HYDROX reactor, the fluid is subjected to compression and decompression processes, causing cavitation and expansion of bubbles. When the expansion force is greater than the surface tension of the fluid, the fine bubbles burst instantly, which causes the water to crack to produce hydroxyl radicals OH-. Generate final products (: 0 ₂ and 11 ₂ 0, sterilization;

e. When the water leaves the reactor, a part is discharged through the outlet valve, and most of the liquid is recirculated and enters the suction port of the pump for further processing. Due to the recirculation of the liquid, the residence time of the fluid in the reactor is increased, so as to improve the degradation rate of the harmful substances by the HYDROX device;

f. After the HYDROX device, the effluent depends on its own pressure, enters the municipal pipe network, or is reused as backwash water for gravity continuous belt filter.

BMS system

BMS systems are included in the fermentation tank, decomposition tank, digestion tank and / or effluent tank in the BMS process. The BMS system is Best- Microorganism- System, which mainly consists of (a) a porous carrier and (b) a multi-family microorganism coexisting on the porous carrier. A particularly preferred BMS system also contains; and (c) a microbubble supply device (see Figure 1). Porous carrier

The preferred porous carrier of the present invention is a wooden carrier, in which components that are liable to cause spoilage have been removed, but cellulose, lignin and pentosan components remain. The porosity of the present invention is 75-85%, and when placed in water, it can be semi-suspended in water, thereby increasing the gas, liquid, and solid three-phase contact areas.

In addition, the wooden carrier of the present invention has pores of different sizes and depths, thereby forming a certain degree of anaerobic, facultative and aerobic regions, thereby providing suitable growth environments for different types of microorganisms.

As used herein, "biological growth device" refers to a porous carrier carrying BMS polybacterial microorganisms. Multiflora

Symbiosis and coexistence on a porous carrier A multifamily microorganism is an aggregate composed of a variety of bacteria, which contains microorganisms selected from the group consisting of photosynthetic bacteria, lactic acid bacteria, yeasts, actinomycetes, and the like.

The microorganisms that can be used in the present invention are not particularly limited, and may be any bacteria that decompose and utilize various pollutants such as organic matter, sulfide, nitrogen oxide, and organic phosphorus in sewage. As for the main types of microorganisms mentioned above, photosynthetic bacteria are mainly used to break down low fatty acids and aromatic compounds; lactic acid bacteria mainly break down proteins and substances such as glucose, lactic acid, acetic acid, and propionic acid; yeasts are mainly excellent for high-concentration organic wastewater Effect; Actinomycetes mainly degrade a variety of organic substances including aromatic compounds. Representative examples of microorganisms include, but are not limited to: ammonium bacteria, nitrifying bacteria, denitrifying bacteria used to eliminate NH ₃ ; sulfur sulfide bacteria (such as Thiobacillus) used to eliminate sulfide, filamentous sulfur bacteria (such as Bayesian Sulfur bacteria, sulfur-producing bacteria), photosynthetic sulfur bacteria (such as green sulfur bacteria, red sulfur bacteria); ammoniating bacteria (such as Bacillus), nitrifying bacteria, denitrifying bacteria, phosphorus bacteria (such as sand Lectobacillus). These microorganisms can be commonly used in the field, and can also be obtained by conventional methods from environments such as garbage dumps and wastewater treatment plants. Micro bubble supply equipment

The micro-bubble supply device is located under the wooden carrier to provide oxygen for the multi-flora microorganisms.

The air supply tube of the micro-bubble supply device has many fine pores (preferably "I" pores), and the cross section of the pores has a certain slope, so that the micro-bubbles are not only small and dense, but also can be automatically covered to prevent blockage when the air supply is stopped. .

The BMS system reactor simulates a natural environment ecosystem with a long food chain consisting of many types of microorganisms. The BMS flora residing in the carrier is usually dormant. When exposed to wastewater and biological agents, the flora quickly changed from dormant to active. Organic matter in the wastewater is adsorbed to the bacteria within a short time (about 10-30 minutes), and soluble matter penetrates directly into the cells. The nutrients entering the cells are converted into simple inorganic substances such as carbon dioxide and water by a series of biochemical reactions under the action of intracellular enzymes. At the same time, energy is generated. Microorganisms use the energy released from the breath and the intermediate products produced during the oxidation process to synthesize cellular substances, causing the bacteria to reproduce in large numbers. Microorganisms continue to carry out biological oxidation, and organic matter in the environment is continuously reduced, so that sewage is purified.

The BMS system used in the present invention has the following main features;

(1) The BMS system simulates the natural ecological environment, and its purification process and process principle are different from traditional biological treatment processes. The BMS system can not only rapidly decompose organic substances, suppress and eliminate the generation of odors such as hydrogen sulfide, ammonia, but also make the entire No residual sludge is discharged during the process.

(2) The BMS biological treatment system is different from the traditional biological treatment method. The system has neither the clogging phenomenon of the traditional biofilm method nor the sludge swelling phenomenon of the traditional activated sludge method; oxygen transfer efficiency, oxygen utilization ratio, treatment efficiency, Biomass, activity, economics and other indicators are significantly better than traditional biological treatment methods; the system has high-efficiency nitrogen and phosphorus removal and deodorization effects that traditional biological treatment methods cannot replace. (3) The wooden carrier of the present invention is different from the currently commonly used biological carriers. The carrier has a moderate specific gravity within the carrier, forming an ecological system with biological species and a reasonable number distribution.

(4) An efficient micro-aeration system with self-resistance can not only generate uniform fine bubbles, but also not block, and provide a sufficient oxygen source for the microbial flora. The water-gas ratio of the treatment system is about 1 / 3-1 / 2 of traditional biological treatment, with low energy consumption and high oxygen utilization rate.

(5) The micro-bubble supply equipment provides the best conditions for the growth and reproduction of microorganisms.

(6) High equipment processing efficiency (see Figure 2 for COD removal efficiency), small footprint, low investment cost, and high degree of integration. Example:

A comprehensive sewage treatment method includes primary treatment and secondary treatment. It is characterized by a high-efficiency solid-phase blocking device for primary treatment. The secondary treatment is the physical and chemical treatment of BMS flora sludge-free biological wastewater treatment technology (BMS for short) and mechanical energy to generate hydroxyl radicals and chemical oxidation pollutants. Technology (referred to as

HYDROX). The sewage treatment process is as follows: the sewage first enters the solid-phase high-efficiency holding device, intercepts the impurities, enters the BMS stage, and is finally treated by HYDROX to produce water.

Due to the complicated source of sewage, it is necessary to set up a solid phase material efficient blocking device to ensure the normal operation of the subsequent processing device. A gravity continuous conveyor belt filter with a high degree of automation is used instead of the grid device. The sewage first passes through a gravity continuous conveyor belt filter. The sewage contains a large number of large particles of suspended matter and floating matter, and some of the suspended matter are trapped. Removing the above substances has an important protective effect on the pump unit and subsequent processing structures. The retentate is collected and transported by an automatic solid-phase collection device. The DZ-0.7-500 gravity continuous belt filter uses German technology applied to sewage treatment. The filter has a high rejection rate and a low moisture content in the collected solid phase. There is no need to set up a dewatering device, and the collected materials can be transported directly.

Sewage is filtered by a belt filter and gravity flows into the BMS biological regulation tank. When the amount of sewage varies greatly within a day, a regulating tank needs to be set up. The regulating tank is one of the main sources of odor. The BMS biological conditioning tank is equipped with high-efficiency microporous aeration equipment, a variety of BMS bacteria and suspended biological growth devices, forming a three-phase fluidized biological reaction tank. Due to the design of the aeration tube position and aeration volume in the tank, The circulatory system forms a certain proportion of anaerobic, facultative and aerobic biological areas. Sewage is repeatedly processed by the A / A / O biological treatment process in the pond along the system water flow direction. Bio-growth adsorbs organic matter, especially macromolecular insoluble organic matter, and many kinds of symbiotic bacteria quickly digest and decompose organic matter. The BMS biological treatment system is used as the biological regulation tank, The water quality and quantity can be adjusted, and the odor can be suppressed and eliminated by the BMS flora. The BMS bacteria can digest and remove nitrogen and phosphorus and oxidatively decompose organic matter, and cushion the impact load, which can ensure the normal working conditions of subsequent devices. The removal rate of suspended matter in the BMS biological treatment tank system is 80%. At the same time, the removal rate of suspended matter in the primary treatment is 82%, and the removal rate of COD is about 30-40% through biological flocculation and biological oxidation. These two indicators can effectively ensure the normal working conditions and processing efficiency of HYDROX.

The effluent of the BMS biological regulation pond flows into the middle pond by gravity, and the water level alarm device and automatic control system are set in the pond. The water level is lower than the minimum level. The effluent of the intermediate pool is pressurized and decelerated by the HYDROX working pump, and then enters the HYDROX reactor after the fluid is compressed and decompressed, causing cavitation and expansion of bubbles. When the expansion force is greater than the surface tension of the fluid, the fine bubbles burst instantly and cause local high temperature (2000k) and high pressure (up to 200 bar), which causes the water to crack and generate hydroxyl radicals OH-. A strong oxidant, a hydroxyl radical, can oxidatively decompose organic compounds to produce final products ( ₀₂ and 11 ₂ 0, which are sterilized. When water leaves the reactor, a part is discharged through an outlet valve, and most of the liquid is recirculated and entered the pump suction port again. Treatment. Due to the recirculation of the liquid, the residence time of the fluid in the reactor is increased to increase the degradation rate of the harmful substances by the HYDROX device. After the HYDROX device, the effluent can enter the municipal pipe network or be reused as an intermittent process by its own pressure. Type gravity continuous belt filter backwash water.

The effluent indicators are lower than the discharge requirements, and the COD removal rate of HYDROX system is 85%, which can completely eliminate pathogens. The treated water quality index: COD <60mg / L, BOD ₅ <15mg / L, NH ₃ -H ^ 8mg / L, TP 0.2mg / L, SS 20mg / L. The beneficial effects of the present invention are that since the first-stage treatment uses a solid-phase material retention device with advanced technology and a high degree of automation, a gravity continuous conveyor belt filter, the interception efficiency is high, the solid-phase material moisture content is low, and the traditional processing system can be omitted. Dewatering device. The BMS bio-regulation tank can not only balance water quality and quantity, but also remove part of COD and most of suspended matter. BMS bacteria can remove nitrogen and phosphorus and oxidatively decompose organic matter, and buffer shock load to ensure normal working conditions of subsequent devices. The BMS biological treatment tank system has a suspended matter removal rate of 80%. At the same time, through biological flocculation and biological oxidation of insoluble organic matter, the primary treatment suspended matter removal rate is 82%, the COD removal rate is about 30-40%, and there is no remaining in the BMS biological adjustment tank. The sludge is discharged, so the whole process does not need to be provided with a sludge treatment device, and the investment and operating cost of the treatment system are low. HYDROX physical and chemical reactor The strong oxidant-hydroxyl radical oxidizes and decomposes organic matters and various reducing substances, and sterilizes. HYDROX system COD removal rate is 85%, which can completely eliminate pathogens. The process is odorless and tasteless, and the environmental sanitation conditions are good.

Claims

Rights request

1. A comprehensive sewage treatment method, including primary treatment and secondary treatment, which is characterized in that the primary treatment is carried out by a solid-phase material high-efficiency loading device, and the secondary treatment is a technology for biologically treating sewage without sludge by BMS flora. The BMS technology is combined with HYDROX technology, which is a physical and chemical treatment technology that generates hydroxyl radicals and chemically oxidized pollutants by mechanical energy. The sewage treatment process is: The sewage enters the high-efficiency solid-phase blocking device first, and the impurities enter the BMS treatment stage. Finally, Water is treated after HYDROX treatment.

2. The method according to claim 1, characterized in that the high-efficiency solid-phase material holding device is a gravity continuous conveyor belt filter, and the sewage first passes through the gravity continuous conveyor belt filter. The sewage contains a large number of large particles. Suspended matter, floating matter and part of suspended matter are intercepted. The retentate is collected by the solid-phase material automatic collection device and then transported. The sewage is filtered and intercepted by gravity to flow into the BMS biological oxidation regulating tank.

3. The method according to claim 1, characterized in that the filtered and intercepted sewage enters the four-cell sub-cell of the BMS biological oxidation regulating tank in sequence, and the four-cell sub-cells are all three-phase fluidized biological reaction tanks. BMS multi-family microorganisms, fillers and suspended biological growth devices and high-efficiency micro aeration tubes are installed. The processing steps are:

c. Digestion tank: The effluent from the decomposition tank enters the digestion tank. By adjusting and cultivating a large number of cocci in the BMS multi-organism microorganisms, it can swallow and digest various decay compounds and bacilli. Cycle

d. Outflow pond: After the effluent from the digestion tank enters the outflow pond, it is further gravity-flowed into the intermediate pond after further aerated biochemical treatment.

4. The method according to claim 1, characterized in that the effluent of the BMS bio-oxidation regulation tank enters the middle tank by gravity, and the tank is equipped with a water level alarm device and an automatic control system. The processing steps are: a. The water level is lower than the minimum water level, HYDROX The working pump is self-closing, higher than the set water level, and automatically starts the pump; b. The water from the intermediate pool is pressurized and decelerated by the HYDROX working pump and enters the HYDROX reactor after decelerating, causing the fluid to undergo compression and decompression, causing cavitation and air bubbles. Expansion when the expansion force is greater than the fluid When the surface tension of the micro-bubble bursts instantly, the water is cracked to produce hydroxyl radicals OH-; c. When the water leaves the reactor, part of it is discharged through the outlet valve, most of the liquid is recycled and enters the suction port of the pump Process again;

d. After the HYDROX device, the effluent can enter the municipal pipe network by its own pressure, or be reused as backwash water for the gravity continuous belt filter.

5. The method according to claim 3, wherein the fermentation tank, decomposition tank, digestion tank and / or effluent tank in the BMS process comprise a BMS system, the system comprising (a) a porous carrier, (b ) Symbiosis Coexisting multi-flora microorganisms on a porous support.

6. The method according to claim 5, wherein the BMS system further comprises (c) a micro-bubble supply device.

7. The method according to claim 5, wherein the porous support is a wooden support with a porosity of 75-85%, and can be semi-suspended in water when placed in water.

8. The method according to claim 5, wherein the multi-organism microorganisms coexisting on the porous carrier contain the following microorganisms: photosynthetic bacteria, lactic acid bacteria, yeasts, and actinomycetes.