As one of the industrial wastewater coating wastewater, mainly from pre-degreasing, degreasing, surface adjustment, phosphating, passivation and other body pre-treatment processes, in particular the electrophoretic waste water, spray paint wastewater complex, high concentration, poor biodegradability . Painting wastewater treatment mainly uses the sub-quality treatment, coagulation and sedimentation, coagulation floatation, sand filtration and other processes on the coating wastewater treatment. 1, coating wastewater treatment characteristics 1, Phosphating - Spray painting is a commonly used method of steel surface protection and effective treatment. In recent years, with the rapid development of China's automobiles, motorcycles, household appliances and other industries, the phosphating-spray painting process has been developed rapidly and its application is getting wider and wider. The large number of applications of these processes is bound to produce a large number of harmful waste water pollution of the environment. From the aspect of environmental protection, it is imperative to research and develop and popularize the application of reasonable and reliable coating wastewater treatment technologies. 2, the source of coating wastewater and its harmfulness Iron coating process: Pre-degreasing - degreasing - washing - washing - washing - surface adjustment - Phosphating - washing - washing - washing - drying - painting - drying. Plastic parts coating process: degreasing - washing - washing - washing - activation of the interface - drying - spray paint - bake thousand - spray conductive agent - electrostatic spray paint - drying. After degreasing the water contains a lot of surfactant and emulsified oil, COD in water: about 700mg / L, BOD about 200mg / L, this kind of water if untreated directly discharged into the river, the waste water The organic matter in the water decomposition consumes a large amount of dissolved oxygen, thus undermining the balance of oxygen in the water, the water quality produce stench. Phosphatized washing water containing more than the emission standards of nickel ions (Ni ten), zinc ions (Zn ten) and other heavy metals. As we all know, nickel ions are carcinogens; excess zinc has obvious toxic effects on aquatic organisms. In the painting process will produce paint fog, it is necessary to the normal production will be discarded paint spray removed from the spray booth, a common and effective way is to paint the side of the line (that is, the population of the exhaust duct) to set the curtain, so that the curtain The agent absorbs most of the paint mist, and the exhaust gas that has not been absorbed by the water curtain is treated again by the method of treating the exhaust gas. A wide range of paint, painting shop paint formulations are kept confidential, but regardless of any paint, paint and organic solvents are toxic, or even very toxic. Organic solvents are usually the following types: aromatic type: such as toluene, xylene, ethyl acetate and other vinegar: such as acetic acid vinegar, butyl acetate and other ketones: such as acetone, cyclohexanone and other alcohols: such as ethanol , Butanol, isopropanol and other curtain agent - is generally composed of caustic soda and alkaline and can absorb paint mist composite organic composition. Water spray paint mist, the composition of the water becomes very complex, toxic - also large, high organic content, according to analysis of its CODcr often at thousands of mg / L, and sometimes up to 13000mg / L. Although scouring water is usually recyclable after scum (or sediment) scum removal, there are also two things that must happen: it is that part of the curtain water is drained into waste water and replenished with enough fresh water and dragee; The second is after the curtain water cycle - all the updates after the regular cycle of use. This kind of high content and very toxic water curtain water directly discharged into rivers and lakes (untreated), which is harmful to human beings, is unimaginable and must be dealt with. 3, process flow 3.1, inorganic waste, inorganic waste water treatment process 3.2, organic waste, organic waste water treatment process 4, processing technology 4.1, waste treatment process Due to the high concentration of waste liquid pollutants, the number of emissions instability, the discharge time is not fixed, so waste should not be directly discharged to the automatic control of the wastewater treatment tank. We are the waste into inorganic, organic two, were pre-treatment. According to the test results, the waste treatment methods are summarized as follows: 4.1.1 Inorganic waste disposal methods: per waste liner basis Add 0.50-1.Okg of calcium chloride, 0.50-1.Okg 1 # coagulant and sodium hydroxide solution was added to adjust the pH of the solution to 10-11, pre-precipitation of phosphate and heavy metal ions. 4.1.2 organic waste treatment methods: add per person basis 0.50-1.Okg Demulsifier 1 # and adjust the pH of the solution to 8-9 pre-demulsification. After the waste liquid is pre-treated, it is pumped to the corresponding wastewater treatment tank respectively for further treatment. 4.2 Wastewater Treatment Process 4.2.1 Inorganic wastewater treatment process The optimum pH value of the precipitate of freshly formed Ca3 (P04) 2 was above 10.50 due to Ni (OH) 2 precipitation. The Zn2 + generated Zn (OH): the optimum pH range of precipitation is 8.5-10, so to be divided into two steps precipitation. 4.2.1.1 step - step chemical precipitation process conditions: per waste per meter automatically added 0.1-0.2kg calcium chloride, 0.1-0.2kg1 # coagulant, 3-4mg1 # flocculant, and by pH-controlled device , Automatically added NaOH solution to pH10.5-11.2, after mixing with drugs, the waste water through the sedimentation tank with a honeycomb accelerated precipitation tube to accelerate the sedimentation of Ni (OH) 2, Ca3 (P04) [also have Zn (OH): sedimentation], the supernatant overflow to the sedimentation tank. Factors affecting the effect of chemical precipitation treatment: (1) the amount of calcium chloride: calcium chloride is both a precipitating agent, but also inorganic coagulant, the experimental results per ton of wastewater plus 0.1-0.2kg calcium chloride is appropriate. Addition of less, precipitation is poor, the cohesive effect is poor, resulting in a high Nit Nitrite content of the supernatant resulting in Nit Nit Nitric Oxide emissions exceeded; excessive use of calcium chloride, Ca (OH): precipitation will be too much, resulting in Sludge volume and waste of medicines, increasing the cost of wastewater treatment. (2) The dosage of 1 # coagulant: The experimental results add 0.1-0.2kg1 # coagulant per ton wastewater. The dosage is too small, the cohesive effect is poor, reach the purpose of treatment; excessive use, not only sludge, and the mud is too loose, the settlement effect is poor, but will make the treatment effect worse, but also a waste of medicines. (3) 1 # flocculant dosage: It is the role of adsorption, tape, adhesion and so on, the coagulation of small particles flocculation into a large proportion of large particles of the network, thus accelerating the settlement of sludge. We found through experiments to wide supply, flocculation effect, good adaptability and wide 1 # flocculant. And determine the amount of 3-4n na Lo (4) Effect of pH value: Ni (OH) 2, Ca3 (P04): The optimum pH value for precipitation is 10.50 or more. We use 10.50-11.20, so that both to meet the requirements of precipitation, but also save the consumption of alkali and the next - step acid consumption. (5) Precipitation time: The settling time can meet the requirements in about 1 hour. The longer the settling time is, the better the settling effect is. However, if the settling time is too long, the area of ​​the sedimentation tank is large and the precipitation time is 1.5 hours. 4.2.1.2 The second step and the precipitation treatment process conditions: the pH control device to control the amount of sulfuric acid added to pH8.5-9.0, and per waste water meter automatically added 3-4mg / 1 # flocculant. Because of the presence of a portion of the coagulant in solution in the pre-step weakly alkaline medium, no coagulant is added at this time. After mixing the reaction, the wastewater is accelerated sedimentation through a pool of honeycomb sedimentation inclined tubes. After two-step precipitation, the supernatant is basically colorless and transparent, pH7.5-8.6, Ni <0.10mg / L, Zn <1.10mg / L, and then by the micro-filter to ensure that all indicators are eligible for discharge. Pogo Pin Connectors,Pogo Pin Magnetic Connector,Pogo Pin Connector Production,Pogo Pin Spring Connector DA CHENG MINGHUA LIMITED , https://www.alpsswitch.com