since shenzhen qingquan knowledge seminar-oily sewage treatment technology and key technologies entered the new century, with the rapid improvement of market economy level in china, all walks of life have achieved very rapid development, and the living standards and quality of life of urban residents have also been significantly improved, but at the same time, china's ecology. the environment has also suffered serious damage. various kinds of pollution are continuously eroding the ecological environment of our country. among them, water pollution is a complex subject with many sources of pollution, and the treatment of oily sewage is a very difficult task in china's water pollution treatment work. we should fully analyze the source of oily sewage, analyze its harm, clarify the working process of oily sewage treatment, so as to formulate a scientific work. reasonable countermeasures. in this paper, the sources and hazards of oily sewage, the process flow of oily sewage treatment and the key technical methods of oily sewage treatment are analyzed and analyzed in detail, and the oily sewage treatment work in china is discussed in detail.
1. sources and hazards of oily sewage
1.1 source analysis of oily wastewater
the sources of oily wastewater in china are very extensive. oily wastewater will be produced in the process of steel refining, industrial production, oil exploitation, pesticide and food processing. these oil pollutants mainly exist in four forms: dissolved oil, dispersed oil, slick oil and emulsified oil.
(1) petrochemical industry. in china's petrochemical industry, oil-bearing sewage will be produced at almost any stage from initial exploitation to final transportation and consumption. with the rapid development of science and technology in china, tertiary oil recovery technology has been widely used, which improves the effect of oil displacement, but also makes pollution. the composition of water is more complex.
(2) chemical pharmaceutical engineering. the main source is oily sewage from high concentration process. in the manufacturing process, water and lubricant will be used in a large number of stages, such as raw material reaction, product separation and raw material pretreatment, so a large number of oily sewage will be produced in the later stage.
(3) metal smelting industry. in the process of metallurgy, we should cool, clean and lubricate the materials or equipment contacted with oil, and the lubricating oil may also be directly contacted with them, so oily sewage will be formed.
(4) food processing and production. in the process of food processing and production in our country, oily sewage is produced in the stages of equipment cleaning and machine lubrication.
1.2 hazard analysis of oily sewage
(1) oily sewage pollutes drinking water sources. if our daily drinking water source is polluted by oily sewage, not only people and livestock will be infected with diseases, but also food poisoning may result in great harm. in addition, oily sewage is also a certain amount of carcinogens containing oil, so it may increase the incidence of cancer in oily sewage polluted areas. rate;
(2) oily sewage is discharged into rivers and lakes. the density of oily sewage is lower than that of normal pure water, so once oily sewage is discharged into rivers and lakes, it will adhere to the surface of water, the atmosphere and water gas can not be exchanged normally, the oxygen content in water is declining continuously, then aquatic plants can not grow normally and the quality of water body is affected. as a result, the utilization value of water resources has been greatly reduced.
(3) oily sewage enters the soil. if oily sewage is used as irrigation water to irrigate soil, then oil stains will deposit on the surface of crops, soil can not effectively exchange with the outside air, soil metabolism slows down, thus affecting the normal growth of crops, and even lead to crop death, if oily crops are eaten by human beings. it will also do harm to our health.
2. process flow of oily wastewater treatment
usually, in the process of treating oily wastewater, the process is to separate oil and water for the first time, and then separate oil and water further by coagulation or floatation. at this time, we should add pam and pac quantitatively to ensure the full occurrence of flocculation and coagulation reaction. the process flow can avoid the occurrence of oil blockage treatment devices, and the degreasing performance of each device can also be fully developed. when oily sewage enters the highly efficient combined air flotation, a large number of ss and oil have been removed. at this time, we should first measure the water quality. if the water quality still does not meet the standards, then we should use activated carbon filter or quartz sand filter to filter it, to ensure that it meets the quality standards before it can be discharged. the main purpose of our first oil-water separation is to reduce the emulsification degree of oily wastewater. if oily wastewater with high solidification point and large particle size should be treated with heat preservation and heating equipment. if oily wastewater with small oil-water ratio difference should be filtered. when choosing the material of the treatment device, we should take the temperature parameter into full consideration. when the high-efficiency combined air flotation slag is discharged into the sludge storage tank, the pneumatic diaphragm pump is pumped to the chamber filter press for filtration and dewatering, and finally it is transported to the outside for treatment.
3 key technological methods for oily sewage treatment
3.1 coagulation.
this method is mainly aimed at the separation of tiny suspended oil particles and colloidal oil particles in oily sewage. firstly, we should add a certain amount of chemicals into oily sewage.
