Product Name: wastewater treatment equipment Features: urban sewage through level after secondary treatment, in order to achieve a certain degree of reuse water standard sewage water reuse as a further treatment process for the production or life. Scope: suitable for electroplating industry, PCB industry, chemical industry, food processing, power industry, textile, paper industry, leather industry, steel industry, mining and smelting. Wastewater treatment process 1, the physical chemistry physical chemistry method is by mechanical principles closure, chemical precipitation, chemical oxidation, ion exchange to remove contaminants from the water. ① mechanical closure. The easiest method is to filter mechanical closure, pure quartz sand filtration media commonly used for suspended solids and colloids have good removal, water turbidity, SS generally lower, for COD and color also have some effect. ② chemical precipitation. Coagulation and sedimentation process is the most commonly used wastewater treatment process, the majority of our sewage plant in depth treatment process are used in this method. Adding chemicals to the water, after hydrolysis agents and pollutants interact to form large particles through floc coagulation process, be separated by sedimentation or flotation. Coagulation and sedimentation process economics, mature, but the treatment effect influenced by changes in water quality (algae, Ph, temperature, etc.), time and higher water quality requirements, the process is unable to meet the treatment effect. ③ chemical oxidation. Chemical oxidation is the basis for a variety of advanced oxidation technology, which is the use of chemical oxidants oxidizing pollutants into slightly toxic, harmless substances or converted to form tractable. Common chemical oxidants including H2O2, O3, ClO2, K2MnO4, K2FeO4 like. O3 is a strong oxidant, almost all the elements in the periodic table, except the reaction of platinum, gold, iridium, fluorine and, especially in an acidic solution, the standard redox potential Eo = 2.107V after fluorine, having strong oxidation. ④ ion exchange: ion exchange resins have been widely used in various fields. Ion exchange method is the use of the characteristics of the resin material in water contaminated by mines or exchange OH- adsorbed on the resin, to achieve the purpose of removal of pollutants. 2, biological method using microorganisms themselves may organics, nitrogen-containing compounds, phosphorus compounds and other substances decompose to produce characteristic energy and absorption of nutrients, cultivate certain microorganisms, use this feature to their process wastewater pollutants, achieve the purpose of water purification. Lower operating costs in general biological treatment, biological culture acclimation ripe, usually without artificial enhancement of pollutants in the water can be removed in the course of its own growth, the process is simple and easy to manage. Biological treatment methods include aerobic and anaerobic treatment of two categories. Biofilm is aerobic biological treatment and activated sludge and the like, with high efficiency, easy operation and management, etc., play an important role in wastewater treatment. BAF been extensively studied in recent years, a new biological treatment technology, with high efficiency, small footprint, low capital investment, operating costs, ease of management and strong impact load capacity and other characteristics, can be used for SS , removal of organic matter and ammonia, denitrification and other secondary and tertiary sewage treatment, has a good potential for the development and application of advanced treatment of wastewater and reuse resources. 3, a combination of physical and chemical and biological methods due to the biological wastewater treatment plant secondary effluent some contaminants remain high, composition is relatively complex, so in the course of their treatment, either alone chemical method, or biological methods alone are difficult to reuse water effluent meet the national standard, generally a separate process by the impact load is poor, and sometimes resorted to in order to improve water quality, costs will increase even several times. Combined process not only can make full use of the advantages of the process itself, but also can play a different process collaboration, achieve the treatment goal, saving operating costs. Coagulating sedimentation process and biological aerated filter technology portfolio, can be SS in coagulation and sedimentation stage, the removal of part of the organic matter, reducing the SS to the clogging BAF improve backwash cycle time, reduce filter load increase the efficiency of filter, improving water quality, and because the poles barrier, coagulation and sedimentation sewage directly without having to deal with compliance, reduce dosage coagulant drug cost savings. Oxidation technology and biological aerated filter technology portfolio, the former stage of the process the oxidizing strong oxidizing agent to improve the water quality of the structure, will be detrimental to the bioavailability of organic molecules into favor bioavailable small molecule organic compounds, contribute to the strengthening under a stage biological treatment, treatment effectiveness and operational costs much better than the sum of the two processes separate treatment. Select a different oxidant treatment effect will be quite different, mainly due to the different oxidation strength oxidants, change the structure of the different effects of contaminants in water, the degree of improvement of the depth of treatment is different. 4, BAF technology Biological Aerated Filter (referred BAF) is the second third-generation sewage treatment trickling filter biofilm reactor and after filtration and drying systems, which give full play to the role of biological metabolism, physical filtration the role of biofilms and physical adsorption fillers and grading predation of the food chain in the reactor, the biofilm technology not only has advantages, but also plays an effective spatial filter effect [3]. The basic principle of BAF is enhanced on the basis of level to particulate fillers and attached growth biological membrane as the main treatment media, give full play to the role of biological metabolism, physical filtration, biofilm and physical adsorption filler Predation of the role and classification within the reactor of the food chain, to achieve the removal of contaminants in the same unit of the reactor. BAF draws biological contact oxidation reactor design principles and deep bed filtration, eliminating the need for secondary sedimentation equipment. BAF main problems exist as follows, ① BAF influent suspended solids higher requirements, the best control in 60mg / 1 or less, so that the treatment process BAF before high requirements. ② BAF head loss is large, since the residence time is short, nitrification is not sufficient, a large amount of sludge production and poor sludge stability, further treatment difficult. ③ phosphorus removal in general, need to add chemical phosphorus removal. ④ lack of high selectivity, low cost of media, there is no uniform standard filter system. 5, electric adsorption technology (EST) currently produces a large number of wastewater treatment using carbon materials for adsorption for heavy metal ions, organic contaminants and removal of colored substances applied mainly carbon, including granular activated carbon and fibrous activated carbon. Although the activated carbon adsorption to remove pollutants in water and air in applications it has many advantages, but there are also some disadvantages. Advantages electrosorption is: can adsorb and remove biodegradable organic matter; good degree of purification, can be used to deal with a dilute solution system; low energy consumption and low operating costs. Thus electric regenerative adsorption technology of deep purification of wastewater treatment and water separation and recovery of organic matter, adsorbents and so has a good prospect. Moreover electric adsorption method can also be used to enrich valuable chemical or biological substances. EST system original tanks, pumps, pre-filter, EST module, after filter, finished water tank, pipe valve systems, power systems, instrumentation and electrical control system components. EST module is not particularly limited to the original chlorine, organic compounds, high ion concentration, so the main requirement is that the pretreatment filter sediment, suspended solids removal, can usually be PP filter filter, sand filters and other means. If there is high demand for finished water, you can add precision filter, UV disinfection or ozone sterilization and other post-processing device in the EST module. EST work module is a gap-like, back electrode in saturation, it needs to be regenerated. 6, membrane separation membrane separation technology is based polymer membrane as the representative of a new type of fluid separation unit operation technology. Its biggest feature is the separation process is not accompanied by phase change alone some pressure as the driving force will be able to achieve high separation efficiency, it is a very energy-saving separation technology. Microfiltration can remove bacteria, viruses and parasites, etc., but also can reduce the phosphate content of the water. Tianjin Development Zone sewage treatment plant using microfiltration of SBR advanced treatment of secondary effluent to meet the landscape, flushing the toilet and other pavement and municipal use and life Utility needs. Ultrafiltration is used to remove large molecules, for secondary effluent COD and BOD removal efficiency greater than 50%. Beijing Gaobeidian sewage treatment plant using ultrafiltration depth of secondary effluent treatment, water production reached living miscellaneous water standards, reuse wastewater for washing, annual savings of water 4700m3. Reverse osmosis is used to reduce salinity and total dissolved solids removal for secondary effluent desalination rate of more than 90%, COD and BOD removal rate was about 85%, bacterial removal rate of 90%. Myanmar in a power plant using reverse osmosis membranes and electrodeionization hyphenated techniques for boiler feed water. Water treated by reverse osmosis, to remove most of the inorganic salts, organic matter and microorganisms. Nanofiltration reverse osmosis and ultrafiltration between its operating pressure is generally 0.5 ~ 1.0MPa, a notable feature of nanofiltration membranes having ion selectivity, it divalent ions removal of up to 95% or more, a lower monovalent ion removal rate of 40% to 80%. Using membrane bioreactor - NF integration process molasses alcohol wastewater system and achieved good results, the effluent COD less than 100mg / L, wastewater reuse rate of more than 80%. Our membrane technology with the world's advanced level in the field of deep processing big difference. Future research focuses on the development, manufacturing high strength, long life, anti-pollution, high flux membrane material, focus on solving the key problem of membrane fouling, concentration polarization and cleaning.