Can anyone explain the principle and steps of sewage treatment system in a more systematic way

Sewage treatment system sewage treatment for sewage to achieve drainage of a water body or re-use of water quality requirements, and its purification process. Sewage treatment is widely used in construction, agriculture, transportation, energy, petrochemicals, environmental protection, cityscape, medical, catering and other fields, but also more and more into the daily lives of ordinary people. The following is an introduction to several common sewage treatment system. First, SPR high turbidity sewage treatment system along many years of the traditional "primary treatment" and "secondary treatment" water treatment technology and equipment has been difficult to adapt to today's high turbidity and high concentration of sewage purification requirements, the latest invention of the "SPR high turbidity sewage purification system" (U.S. patent) will be the sewage "primary treatment" and "tertiary treatment" procedures combined in a SPR sewage purifier tank design It is designed to combine the "primary treatment" and "tertiary treatment" processes in a single SPR tank and to be completed quickly in a 30-minute process. It allows direct inhalation of suspended solids (turbidity) up to 500 mg / l to 5000 mg / l of high turbidity sewage, after treatment of suspended solids (turbidity) of the effluent is less than 3 mg / l (degrees); it allows direct inhalation of CODcr 200 mg / l to 800 mg / l of high concentration of organic wastewater, after treatment of the effluent CODcr can be reduced to 40 mg / l or less. Only with the engineering investment equivalent to conventional primary and secondary sewage treatment plants and lower operating costs than conventional secondary treatment, it is possible to obtain the effect of tertiary treatment level and realize the regeneration and reuse of municipal wastewater. SPR wastewater treatment system firstly adopts chemical method to make the pollutants in the dissolved state precipitated from the real solution state, and form the colloidal particles or tiny suspended particles with solid-phase interface; selects highly efficient and economical adsorbent to separate the organic pollutants, chromaticity, etc. from the wastewater; and then adopts microscopic physical adsorption method to condense the colloidal and suspended particles in the wastewater into a large and dense floc; and then relies on the cyclone flow and filtration Then relying on cyclone and filtration, hydrodynamic and other principles of fluid mechanics, in the self-designed SPR high turbidity wastewater purifier to make the floc and water rapid separation; clear water through the tank after the formation of a dense layer of suspended mud filtration, to achieve tertiary treatment level, the effluent to achieve the level of reuse; the sludge in the concentration chamber is highly concentrated, and discharged periodically by pressure, due to the low water content of sludge, and dewatering performance, it can be directly into the mechanical dewatering device. Due to its low water content and good dewatering performance, the sludge can be directly sent to the mechanical dewatering device, and the sludge cake after dewatering can also be used to make sidewalk tiles, eliminating secondary pollution. The latest invention of SPR wastewater purification technology with its simple and reliable process, low investment and operating costs, occupies less land, good purification effect of the many advantages will be the world's urban wastewater reuse to create a new road. After the reuse of urban wastewater is realized, it provides the city with a second source of fresh water, which is indispensable for the sustainable development of the city, and its economic and social benefits are immeasurable. SPR wastewater treatment system with distinctive technical characteristics 1, urban sewage and treatment chemicals are mixed mainly in the pump before the suction pipeline, sewage pump impeller, serpentine reaction tube and ceramic ball reaction tank under the combined effect of the completion of the turbulent velocity, mixing time, and hydraulics of the structural data design, to be very full of mixing to achieve the best coagulation purification effect and maximize savings in pharmaceuticals to create a Prerequisites. This is the past conventional primary treatment and secondary treatment of the hydraulic structure can not do. 2, SPR system to deal with urban sewage, the use of more than five kinds of sewage treatment chemicals and their optimal combination of formulations, relying on the chemical reaction to make the sewage in the dissolved state of organic pollutants, heavy metal ions and harmful salts from the water precipitation, solid-phase interface to become tiny particles (which contains a sewage tertiary treatment of the role of). One of the adsorbents, which is very effective and inexpensive, was also chosen to adsorb the organic pollutants and coloration. The disinfectant kills bacteria and E. coli in a 30-minute process. By coagulation of physicochemical adsorption of suspended solids and various types of impurities into a large and dense floc. This is different from the conventional physicochemical method, which utilizes the individual effects of each agent and the cross-linking effect between them. And SPR system using a combination of pharmaceutical formulations, only with very fine hydrodynamic parameters designed SPR sewage purifier and its system to give full play to their role in the conventional water system can not be used. 3, SPR system devices can be in accordance with the formula derived from the simulation test, with the help of atmospheric pressure and flow meters, very accurately add coagulants and flocculants, not due to overdose and cause drug residues in the purified water, and power consumption is very small. 4, SPR sewage purifier internal structure is completely in accordance with the precise design of the coagulation mechanism, the formation of the vortex flow and each part of the appropriate water velocity, so that the colloidal particles have the most collision between the number of times, and there is the optimal flow rate environment required for cohesion and adsorption. Thus, in a very small volume to obtain a very full cohesion effect. This is the conventional water device can not be compared. 5, according to the coagulation of the floc formed by the actual situation, accurately determine the SPR sewage purifier internal hydrodynamic data, so that in the tank in the upper part of the formation of a few dozen centimeters thick, very dense suspended mud layer. All the coagulated effluent must be filtered through this suspended mud layer, before ascending to the upper part of the tank fresh water collection area. It is very successful to play a very important role in the advanced sewage treatment process filtration. This dense suspended mud layer is formed by the sludge in the sewage and coagulation chemicals in the floc itself. With the floc upward movement from the bottom, so that the mud layer of the lower surface layer is constantly increasing, thicker; at the same time, with the filtration hydraulics principle of the formation of the tank bypass flow, guiding the suspended mud layer of the upper surface layer of the mud layer continues to flow into the center of the sludge bucket, the upper surface layer is constantly reduced, thinner. In this way, the thickness of the suspended mud layer reaches a dynamic balance. When the coagulated water from the bottom up through the suspended mud layer, the floc filter layer by interface physical adsorption and electrochemical properties and van der Waals force, the suspended colloidal particles, flocs, bacteria and other impurities are all intercepted in the suspended mud layer, so that the effluent quality of the water to achieve the level of three-tier treatment. As the mud layer is composed of flocs, high density, filtration efficiency is much higher than the conventional sand layer filtration; because it is in a suspended state of floc mud layer as a filter layer, the head (resistance) loss of filtration is very small, so the power consumption is much lower than the conventional sand layer filtration, microporous filtration, or reverse osmosis membrane filtration; and because of the filtration of the mud layer is purified in the process of sewage sludge automatically supplemented by the addition of the sludge, and automatically led away, that is, the filtration of the mud layer itself in the water quality to achieve the level of tertiary treatment. And because the filter mud layer is automatically added by the sludge in the sewage during the purification process, and is automatically led away, that is, the filter mud layer itself is constantly renewed, the filter mud layer always maintains a stable thickness, and always maintains a stable physical adsorption and electrochemical adsorption performance, so it can obtain stable filtration effect. Moreover, it completely eliminates the backwashing of the filtration layer which is essential in the conventional system, as well as the many troubles caused by backwashing. This structure and principle and conventional tertiary sewage treatment filtration device is completely different, there is no expensive reverse osmosis membrane filtration, microporous filtration, or activated carbon filtration and other devices. Therefore, investment savings, low power consumption, low operating costs is the inevitable advantage of the SPR system. 6, SPR system selected flocculant, but also a good sludge filter aid, so the system finally discharged sludge slurry, its dewatering performance is good, can not add another filter aid, it is directly pumped into the filter press dewatering. The sludge cake can be made into sidewalk tiles for reuse without bringing the problem of secondary pollution. It does not have the traditional biochemical method of sludge produced by the high water content, poor dewatering performance of the Achilles heel. 7, this type of sewage purifier has been on the run to deal with pig farm sewage, chicken farm sewage, coal mine pit sewage, pig slaughterhouse sewage, sorghum brewery lees sewage, textile printing and dyeing sewage, recycled paper sewage and urban sewage sewage and so on, containing a large number of organic pollutants and ammonia nitrogen sewage; but also successfully applied to the ceramic plant sewage, wall tile factory sewage, marble buffing and polishing sewage, coal washing sewage, It is also successfully applied to the purification and reuse of sewage with extremely high content of suspended solids, such as sewage from ceramic factory, wall tile factory, marble water grinding and polishing sewage, coal washing sewage, wet dust removal sewage from coal-fired boiler, and quartz sand washing sewage. Authoritative testing departments around the world tested the relevant data of the sewage purifier influent and effluent. The test report form shows that: ammonia nitrogen removal rate can reach 85%, total nitrogen removal rate can reach 95%, organic nitrogen removal rate can reach 96%, BOD removal rate can reach 95%, the removal rate of suspended solids is as high as 98.3%~99.6%, and the turbidity of the effluent water reaches less than 3 degrees (3mg/liter). This is the water purification system in the low investment, low operating costs under the premise of the obtained water indicators. This is the conventional physical and chemical methods and biochemical methods of primary and secondary treatment systems can not be achieved. In addition to the developed countries have a special urban sewage pipeline system, the actual city wastewater is often mixed with a lot of industrial sewage, poor biochemical and pollutant composition of irregular rapid change is the reality we face, and for the degradation of an organic pollutant microbial growth, reproduction process is too long, so the traditional biochemical system is difficult to adapt to today's more and more industrialized city wastewater.SPR system SPR system has the adaptability to deal with a large number of industrial wastewater and physical and chemical methods have the ability to adapt quickly, easy to cope with changes in the quality of sewage inlet through automated means of the system to maintain a stable purification effect. 8, in the SPR system put sterilization and disinfection chemicals, as long as you increase the amount of chlorine (without additional equipment) can play a role in using chlorine to oxidize ammonia, and further improve the efficiency of the wastewater treatment system to remove ammonia and nitrogen. 9, if the SPR system after treatment of ammonia nitrogen content of the effluent has not yet reached the more stringent requirements (such as some developed countries or developed regions will be set as a drainage standard containing ammonia nitrogen below 1 mg / l), can also be followed up in series to set up a level of ion exchange devices, relying on the oblique hair zeolite ion exchange columns ultimately reach the goal of removing ammonia nitrogen. Because of the oblique hair zeolite ion exchange system requires that the suspended solids content of the imported water to be less than 35 mg / l, otherwise it will affect the function and life of the ion exchange column, thus greatly increasing the operating costs of ion exchange. In the past, it was difficult for conventional primary and secondary wastewater treatment units to achieve such a pre-treatment level in a long-term and stable manner, thus limiting the wide application of the ion exchange method for ammonia nitrogen removal technology. Now, the SPR sewage treatment system can absolutely guarantee that the suspended solids content of the purified water is less than 3 mg / l (the actual operation of the suspended solids content of the water more than 1 mg / l), so that the subsequent oblique hair zeolite ion exchange system to remove ammonia and nitrogen load to reduce a lot of the service life of the exchange column will be greatly extended, that is, the ion exchange operating costs will be greatly reduced, the ion exchange method will remove the advantages of the ammonia technology to be more fully realized. The advantages of the ion exchange method of ammonia nitrogen removal technology will be more fully realized. 10, in fact, after SPR sewage purification system after treatment of the water, its suspended solids content is less than 3 mg / l, turbidity is also less than 3 degrees (mg / l), up to the tap water standards, no longer clogging the water pipeline, and has been through a good disinfection. It is very safe and reliable to send this water back to the city as watering water for urban lawns and trees. After SPR system treatment of the effluent water, the residual nitrogen content has been very low, nitrogen as a plant growth nutrients do not have to remove, or do not have to remove so clean. Thus, the investment in deep treatment of nitrogen removal and its operating costs can be eliminated, which not only ensures the environmental quality, but also saves a large amount of money for the community. With this reuse water to replace tap water as urban green water, will greatly save the city's freshwater resources, reduce the pressure of urban municipal departments of the water supply, the overall economic development of the city will have a very great benefit. This is a new concept of urban wastewater reuse. 11, this purely physical and chemical method of sewage treatment system, by the weather, the environment and the influence of human factors less, the operator to control the ability to deal with the system and flexibility are greatly superior to the biochemical method, which is well known. Second, continuous cyclic aeration sewage treatment system (CCAS) (a) Introduction to the CCAS process CCAS process, that is, continuous cyclic aeration system process (Continuous Cycle Aeration System), is a continuous feed SBR aeration system. This process is in the SBR (Sequencing Batch Reactor, sequencing batch treatment method) based on the improvement of the SBR process as early as 1914, that is, successful research and development, but due to the manual operation and management is too cumbersome, backward means of monitoring and easy to block the aerator and other issues and difficult to promote the application of large-scale wastewater treatment plants. Small-scale sewage treatment plant. Into the 60's, automatic control technology and monitoring technology has developed rapidly, the new type of non-clogging microporous aerator has also been successfully developed, for the widespread use of intermittent treatment method to create the conditions. 1968 Australia's University of New South Wales and the United States of America ABJ company developed the "use of intermittent reactor system of continuous water intake, cycle of water discharge, time-delayed aeration aerobic activated sludge process". In 1986, the U.S. National Environmental Protection Agency formally recognized the CCAS process belongs to the innovative alternative technology (I/A), which has become the most advanced computer-controlled biological phosphorus removal, denitrogenation treatment process. CCAS process for sewage pretreatment requirements are not high, only a gap of 15mm mechanical grating and sand sedimentation tank. The core of biological treatment is CCAS reaction pool, phosphorus removal, denitrification, degradation of organic matter and suspended solids and other functions are completed in the pool, the effluent can meet the discharge standards. The pre-treated sewage continuously enters the pre-reaction tank in front of the reaction tank, in which most of the soluble BOD in the sewage is adsorbed by the activated sludge microorganisms and enters into the reaction area at a low flow rate (0.03-0.05m/min) from the main and pre-reaction areas of the lower part of the partition wall. In the main reaction area in accordance with the "aeration (Aeration), idle (Idle), precipitation (Settle), drainage (Decant)" program cycle operation, so that the sewage in the "aerobic - anoxic" repeated to complete the decarbonization, denitrification, and in the "aerobic - anoxic" repeatedly. and phosphorus removal in the "aerobic - anaerobic" repeatedly. The time of each process and the operation of the corresponding equipment are prepared in advance, and can be adjusted by the computer centralized self-control program. The unique structure and operation mode of CCAS process makes it have unique advantages in the process: (1) When aeration, sewage and sludge are in a completely ideal mixing state, to ensure that the removal rate of BOD, COD, the removal rate is as high as 95%. (2) The repeated operation mode of "aerobic-anoxic" and "aerobic-anaerobic" strengthens the absorption of phosphorus and nitrification-denitrification, so that the removal rate of nitrogen and phosphorus reaches more than 80%, which ensures that the effluent index is qualified. (3) sedimentation, the entire CCAS reaction pool is in a completely ideal precipitation state, so that the effluent suspended solids (SS) is very low, low SS value also ensures the removal of phosphorus. The disadvantage of the CCAS process is that the pools run intermittently at the same time, manual control is almost impossible, all rely on computer control, the quality of management personnel of the treatment plant requires high quality, design, training, installation, commissioning and other work requirements are more stringent. (B) domestic and international urban sewage treatment plant development overview Water is an important factor in economic development and sustainable social development. With the continuous expansion of urban scale and population increase, water environmental pollution has become a major problem. Urban sewage is an important cause of pollution of rivers and lakes, and is one of the main reasons restricting the sustainable development of many cities. "Environmental protection" is China's basic national policy, China's sustainable development strategies and countermeasures formulated by the year 2000 governance goals, requiring centralized urban sewage treatment rate of 20%. At present, China is in the urban sewage treatment business in a period of great development, especially with the implementation of the national strategy for the development of the west, central and western China, environmental and ecological protection has been put on the top of the agenda. Urban sewage treatment has received more and more attention since the industrial revolution 200 years ago. The rate of urban sewage treatment has become an important symbol of civilization in a region. In the past 200 years, urban sewage treatment has developed from the original natural treatment and simple primary treatment to the utilization of various advanced technologies, in-depth treatment of sewage, and reuse. Treatment process has also developed from the traditional activated sludge method, oxidation ditch process to A/O, A2/O, AB, SBR (including CCAS process) and other processes to achieve different effluent requirements. China's urban sewage treatment relative to foreign developed countries, a late start, the current urban sewage treatment rate of only 6.7%. At the same time we vigorously cause foreign advanced technology, equipment and experience, must be combined with the development of our country, especially the actual local situation, to explore the actual urban wastewater treatment system suitable for our country. Combined with China's actual situation, with reference to foreign advanced technology and experience, the construction of urban sewage treatment plants should be consistent with the following directions of development: (1) the total investment province. China is a developing country, the capital required for economic development is very large, so strict control of the total investment in the national economy is very beneficial. (2) low operating costs. Running costs is an important factor in the normal operation of sewage treatment plants, is one of the main indicators to judge the merits of a set of processes. (3) Occupying land. China's large population, per capita land resources are extremely scarce. Land resources are an important factor in the development and planning of many cities in China. (4) nitrogen and phosphorus removal effect. With the eutrophication of large areas of water environment in China, the de-nitrogenization and de-phosphorization of sewage has become an urgent issue. China's latest implementation of the national "comprehensive sewage discharge standards" (GB8978-1996) also clearly stipulates that applies to all sewage disposal units, very strict provisions of the phosphate discharge standards and ammonia nitrogen discharge standards. This means that in the future, the vast majority of urban sewage treatment plants have to consider the problem of nitrogen and phosphorus removal. (5) The organic combination of modern advanced technology and environmental protection engineering. Modern advanced technology, especially the emergence and improvement of computer technology and automatic control system equipment for the development of environmental protection engineering provides strong support. At present, most of the sewage treatment plants in foreign developed countries use advanced computer management and self-control systems to ensure the normal operation of sewage treatment plants and stable qualified water, while China is still relatively backward in this regard. Computerized control and management is also bound to be the direction of the development of China's urban sewage treatment plant. (C) Comparison of several treatment systems In order to choose the most reliable process, the most economical investment, the most convenient management of urban wastewater treatment system, combined with the actual situation of the local community, we have researched the mature experience and development trend of domestic and foreign wastewater treatment plants, and made a comparison. At present, most of the domestic and foreign municipal wastewater treatment plant treatment processes use primary treatment and secondary treatment. Primary treatment is the use of physical methods, mainly through the grille interception, sedimentation and other means to remove large suspended solids and sand particles and other substances in the wastewater. This treatment process has matured both at home and abroad, with little difference. Secondary treatment is the use of biochemical methods, mainly through the life of microorganisms and other means to remove suspended wastewater, dissolved organic matter and nitrogen, phosphorus and other nutrients. At present, this treatment process has a variety of methods, in summary, representative processes are mainly traditional activated sludge, oxidation ditch, A/O or A2/O process, SBR and CCAS process. At present, these several representative processes have practical applications at home and abroad. Third, rural domestic sewage non-powered multi-stage anaerobic composite ecological treatment system Rural domestic sewage non-powered multi-stage anaerobic composite ecological treatment system technology is suitable for decentralized household kitchen, laundry, bathing and other low concentration of rural domestic sewage treatment, especially suitable for decentralized households with terrain differences or 2 to 5 joint households of rural domestic sewage treatment. The technology can be used in Luodu Village and Longnu Village, Heilong Town, Qingshen County, Meishan City. Anaerobic biology expert Prof. G. lettinga asserts that anaerobic treatment biotechnology can become the core means of decentralized domestic wastewater treatment mode if there is a suitable post-treatment method to match, and this mode is more sustainable and vital than the traditional centralized treatment method, which is especially suitable for the situation of developing countries. 1. Basic principle For China's current shortage of funds, energy and pollution is becoming increasingly serious status quo, anaerobic treatment technology is particularly suitable for China's national conditions of a technology. But because the separate anaerobic on nitrogen, phosphorus and other nutrients basically no removal capacity, nitrogen and phosphorus in the sewage will make the water body eutrophication. At the same time, separate anaerobic treatment can not remove germs well, anaerobic effluent usually can not meet the national discharge standards. Therefore, anaerobic treatment alone can still only be used as a pre-treatment, and a suitable subsequent treatment unit must be selected. Based on the above background, for the treatment of single-family or joint-family domestic wastewater, a set of mature anaerobic treatment combined with ecological beds has basically been formed, referred to as the non-powered multi-stage anaerobic composite ecological treatment system. The system mainly consists of 2-3 compartments of anaerobic tanks and 1 compartment of composite ecological beds with large specific surface area of gravel, fine soil and other substrates, in which the pools are connected by pipelines, and the sewage stays in the pools for 5 to 7 days. After anaerobic treatment of domestic sewage, suspended solids in domestic sewage can be precipitated, and difficult to degrade organic pollutants are transformed into small molecule organic matter by anaerobic microorganisms. Aquatic organisms can be planted on the surface of the composite ecological bed. Composite ecological bed in addition to play a filtering role, the bed of organic matter can also improve the treatment effect. First, the growth of plants to change the flow pattern of ecological bed, the growth of plant roots and stems on the water flow obstruction is conducive to the uniform distribution of water to extend the hydraulic retention time; Second, the root system of plants to create a micro-environment conducive to the growth of a variety of microorganisms, the extension of plant roots and stems in the plant root system near the formation of nitrification is conducive to the formation of aerobic micro-area, at the same time, away from the root system of the anaerobic zone contains a large number of available carbon sources, which in turn Provides denitrification conditions; Third, plant growth on a variety of nutrients, especially nitrate nitrogen absorption. Sewage by anaerobic "coarse" treatment, the subsequent "fine" treatment unit load is relatively small, which can save the ecological bed of the footprint, the suspended solids in the sewage by the anaerobic reactor, most of which can be effectively removed, which can also prevent the ecological bed of clogging. Clogging. Therefore, this combination can not only effectively remove organic matter, but also effectively solve the current difficulties in sewage treatment of nitrogen and phosphorus can meet the standards. 2. Technical process The process flow of powerless multi-stage anaerobic composite ecological treatment system is as follows: Sewage - Sewage collection system (pipeline) - 3 compartments of anaerobic fermentation tank - composite ecological bed The process is described as follows: (1) Sewage collection system The object of this system is generally for the treatment of sewage produced by the kitchen and the bathing room, and the sewage pipeline is connected by a concealed tank between the sewage pipeline and the sewage pipeline. (1) Sewage collection system The system treats sewage generated from kitchens and bathhouses, and connects sewers and sewage pipes with concealed tanks, and sets up a grating at the entrance of the well to remove large particles. (2) The treatment tank consists of an anaerobic fermentation tank and a composite ecosystem bed, forming an integrated structure. The anaerobic fermentation tank consists of three compartments. The first compartment of anaerobic fermentation is mainly used to regulate the water quantity, and at the same time, it also has the role of uniform water quality and primary sedimentation to some extent; the second and third compartments effectively degrade the organic matter in the sewage, which is favorable for the treatment of composite ecological bed. Calculation of the total volume of the treatment tank: V = Q * T where V - ascending pool design volume (m) Q - ascending pool is expected to deal with the volume of water (m / h) T - sewage in the ascending pool residence time (h) T is generally taken as 6 to 7 days, V - the current demonstration of the success of the pool in rural areas have 3 m and 4.5m. (3) Composite ecological bed structure Composite ecological bed is the main structure in the treatment system, is one or two percolation ponds combined into a rectangular brick structure. The ponds are equipped with substrates such as gravel and artificial soil. (4) Composition and thickness of sand and gravel and artificial soil Ⅰ sand and gravel layer consists of sand and gravel of different grain sizes, generally divided into 3 to 4 layers, sand and gravel using porous, large specific surface area of inorganic substrate. Ⅱ Selection of Artificial Soil There are a wide variety and a huge number of various bacteria, fungi, actinomycetes, algae, protozoa, etc., which are indispensable components to maintain the soil and complete the transformation of matter and energy in the ecosystem function, and they are the decomposers and transformers of the matter and energy cycle in the soil ecosystem. Therefore, artificial soil should be selected from sand, high fertility till loamy soil and grass charcoal. The thickness of artificial soil is generally 10-20cm. 3. Technical characteristics The treatment system has a simple process, good water quality, strong shock resistance, no need for artificial aeration, sludge reflux, mixing and stirring and other measures, there is no large-scale processing machinery and complex operation and control systems, so the operation is extremely simple, does not require a large number of trained operators and managers, is very suitable for the current rural areas of China's urgent need for economic, efficient, energy-saving and energy-saving measures. Rural areas in urgent need of economic, efficient, energy-saving, technologically advanced and reliable sewage treatment process and technology.