Case analysis
CASE ANALYSIS
Product Category: Spray Sewage Treatment Engineering
Project Name: Jiangxi a spraying enterprise sewage treatment project
Pollution control type: spraying production wastewater and daily life sewage treatment
Treatment scale: the daily treatment capacity of 60 tons of implementation of the standard "urban sewage treatment plant pollutant discharge standard" (GB18918-2002) three standards
Treatment process: the combination of coagulation precipitation and air flotation separation method
Project introduction: spraying sewage treatment project, the treatment water volume of the project is 60m °/d, and the treatment effect reaches the third-level discharge standard.

Characteristics and difficulties of spraying sewage treatment
CHARACTERISTICS AND DIFFICULTIES OF SPRAYING SEWAGE TREATMENT
Spraying wastewater mainly comes from pre-degreasing, degreasing, surface conditioning, phosphating, passivation and other car body pretreatment processes. Cathodic electrophoresis process and intermediate coating and topcoat spraying process, automobile coating water contains resin, surfactant, heavy metal ions, pigments and other pollutants, especially the electrophoresis wastewater and painting wastewater have complex components, high concentration and poor biodegradability. Coating wastewater treatment mainly adopts the process of separation treatment, coagulation sedimentation, coagulation air flotation, sand filtration and so on.

Solutions and technical features
SOLUTIONS AND TECHNICAL FEATURES
(1) Physical treatment. There are separation methods, filtration methods, centrifugal separation methods, etc. The physical treatment method of spraying sewage is mainly used to remove suspended solids, jelly and other substances! The evaporation crystallization and high magnetic separation method are mainly used to remove jelly, suspended solids, soluble salts and various metal ions. If the addition of magnet powder and coagulant can also remove other non-metallic impurities.
(2) Chemical treatment. There are neutralization method, coagulation method, oxidation reduction method and so on.
① Neutralization method. The sewage acid-base neutralization, adjust the pH value of the solution, make it neutral or close to neutral, or suitable for the next step of the pH range. Neutralizers used in acid sewage neutralization include waste alkali, lime, carbide slag, limestone, dolomite, etc. Neutralizing agents used in alkaline sewage neutralization include waste acid, sulfur dioxide and carbon dioxide in flue gas. For a factory or an industrial area, when conditions permit, acidic sewage and alkaline sewage should be used to neutralize each other to treat waste and reduce costs.
② Coacervation method. The appropriate coagulant is added to the spraying sewage, so that the colloidal particles in the spraying sewage collide with each other and agglomerate into larger particles, which are separated from the solution. These include a series of complex processes of physical chemistry and colloid chemistry.
③ Oxidation-reduction method. In the redox reaction, the substances participating in the reaction will change their original characteristics and use it to purify water in water quality control and treatment technology.
(3) physical and chemical method. This method is used to treat wastewater with ion exchange, electrodialysis, reverse osmosis, air flotation separation, stripping, stripping, adsorption, extraction and other methods. The physical and chemical method is mainly used to separate the dissolved substances in the sewage, recover the useful material components, and make the sewage get advanced treatment.
(4) Biological treatment method: Also known as biochemical method, it uses the metabolic process of microorganisms to oxidize and decompose complex organic matter in sewage into carbon dioxide, methane and water. There are many types of biological methods, which can be divided into four categories according to the basic types of biological methods, namely, natural oxidation method, biological filter oxidation method, activated sludge method, and anaerobic fermentation method. Due to the complexity of the source of spraying sewage, the whole process of spraying sewage treatment is designed, including process, selection, maintenance, adjustment and management. Segmented treatment of coating and spraying sewage reasonable selection of emulsion and permeable cleaning fluid, so that two-phase or more than two-phase mixed phase body is easy to separate, barrier, but also easy to select the coagulant, to obtain high-fold concentrated liquid for evaporation and combustion.

Effect after treatment

THE EFFECT AFTER TREATMENT

The sewage treatment system designed for the spraying enterprise has good effluent quality, the main water quality index can meet the discharge standard, which can well adapt to the unstable influent water quality, and the effluent of the system can meet the sewage discharge standard, which effectively solves the reality of not meeting the standard. According to the actual requirements and design process, the combination of coagulation precipitation and air flotation separation is used to improve water quality, meet the requirements of effluent standards and ensure the long-term stable operation of the sewage treatment system.