Cavitation Air Flotation Machine for Sewage Treatment in Refinery Factory

//Cavitation Air Flotation Machine for Sewage Treatment in Refinery Factory

Cavitation Air Flotation Machine for Sewage Treatment in Refinery Factory

Cavitation air flotation machine is a special wastewater treatment equipment for sewage treatment, referred to as CAF. The cavitation air flotation machine injects or generates fine bubbles in water, and utilizes multiple physical effects such as tension, buoyancy and pressure of the fine bubbles in the water to adsorb the impurity flocs in the sewage. At the same time, the specific gravity of the bonded body of the impurities and the fine bubbles is smaller than that of the water, and naturally floats to the surface of the water to achieve the purpose of separating from the liquid and purifying the water body. Cavitation air flotation technology treats oil, gel and solid suspended matter in urban sewage and industrial wastewater, thus effectively alleviating the damage caused by production and domestic sewage to the overall environment, and is an effective means to protect the environment.

Cavitation air flotation is mainly divided into five parts, a gas-filled section, an air-floating section, a mud scraping system, a solid waste discharge system and a partial water return system. Refining is a heavily polluting production industry, so doing a good job in refinery waste disposal is of great significance to environmental protection. Refineries produce large amounts of pollutants every day, especially industrial wastewater. The wastewater produced by the refinery production unit has a large oil content and a high content of organic components (for example, the COD concentration is high), the biodegradability is poor, and the concentration of biochemical components such as ammonia and nitrogen is high, and a certain concentration of volatile phenols and sulfides is also contained. The refinery’s sewage water discharge has a large fluctuation range, and the sewage water quality changes are also unstable. Therefore, some simple traditional sewage treatment technologies are difficult to make the discharge water quality meet the national emission standards.

Cavitation air flotation machine for refinery sewage treatment

Refinery wastewater is mainly produced by direct distillation of crude oil or cracking and distillation of heavy oil. Refinery wastewater will generally be classified according to the classification of wastewater quality. According to its characteristics, sewage is divided into free oily wastewater, emulsified oil wastewater, cooling water, boiler drainage, sulfur-containing wastewater, alkali-containing wastewater, and acid-containing wastewater. Cavitation air flotation machine can play a huge role in the primary sewage treatment, which can effectively decompose and remove the oil slick, emulsified oil and suspended solids in the refinery sewage.

The sewage after sorting and diverting enters the inflating section, and the vortex aerator in this section uses a diffusing impeller at the bottom of the liquid to rotate at a high speed at the bottom of the liquid to create a certain vacuum area. Then the air duct can transfer the air on the water surface to the underwater to fill the vacuum area, and the oxygen in the air is also input into the water to generate fine bubbles. The fine bubbles enter the water body and begin to adhere to the impurities in the water body, and the density between mixture and the water body is not balanced, generating a certain buoyancy. The mixture of microbubbles and impurities enters the air flotation tank with the agitation impeller stirring at the bottom of the water, and spirals up to the water surface through the air flotation tank. During the floating process, the fine bubbles continuously adsorb impurities, particulate matter and emulsified oil in the water body. The vortex aerator forms an open and complete return line from the aeration section to the air floatation tank, which facilitates the formation of a negative pressure zone at the bottom of the water. The formation of the negative pressure zone ensures the generation of fine bubbles and ensures air floating section can work smoothly.

At this time, the pollutants in the water are pushed from the inlet end of the flotation tank to the outlet end, and then enter the scraping system. The chain scraper in the scraping system can remove the pollutants floating on the water surface and discharge the sludge into the pipeline. The sludge discharge pipe is an integral part of the solid waste discharge system. The auger in the pipeline pushes the sludge into the mud collection tank to form a complete solids discharge step. Purified sewage flows into the overflow tank for biochemical treatment to form a recycling of water resources.

Cavitation air flotation machine technical parameters

  • Model of cavitation air flotation machine is RN- PRQF30
  • Treatment capacity is 30m3/h
  • Water Pump Power is 4 kw
  • Scraper Power is 0.37kw
  • Size of CAF machine is 5800*1200*1500mm
Cavitation Air Flotation Machine for Sewage Treatment in Refinery Factory
CAF - Cavitation Air Flotation Machine for Sewage Treatment in Refinery Factory
Cavitation Air Flotation Machine for Sewage Treatment in Refinery

Cavitation Air Flotation Machine features

Cavitation air flotation machine has a simple structure and is mainly composed of air floating box, electric motor, hollow main shaft, impeller, mechanical seal and so on. Regardless of the large effluent tank, a cavitation air flotation machine can complete the entire air flotation process of the initial treatment of sewage. Moreover, cavitation air flotation machine has no pressure vessel, air compressor, circulating pump and the like, and thus the equipment investment is small and can be installed directly in the sewage sump.

The equipment has a small footprint and less investment in civil works, which can reduce the production cost of the refinery. At the same time, due to the simplicity of the equipment, the operation of the equipment is relatively simple and the operating cost is low. Therefore the labor intensity of the operating equipment and the maintenance cost of the equipment are greatly reduced. Water demand in the refinery is large, and the daily sewage discharge is also rising and the composition of the sewage is complicated. The aeration of cavitation air flotation machine is stable and huge, and the air floatation effect is good, and the amount of refinery sewage and the complicated sewage water quality can be fully coped with. The effect of cavitation air flotation machine on sewage treatment is very significant: the removal rate of petroleum and solid suspended solids in sewage can exceed 80%. Cavitation air flotation machine can exert a huge effect in the refinery sewage treatment, effectively removing water pollutants such as oils, gels and solid suspended matter generated during the refinery production process.

At this stage, cavitation air flotation machines are widely used in most oil refining enterprises. Because cavitation air flotation machine can effectively improve the oil removal rate of refinery wastewater, and meet the water demand, it also has the characteristics of saving investment, less land occupation, energy saving and low operating intensity, so it is widely recognized by most oil refining enterprises. Therefore, the promotion of the equipment plays an important role in the development of the refining industry.


Shandong RUNNENG Environmental Technology Co., Ltd (RUNNENG) had been dedicated to supplying one stop wastewater equipment and Water Resource Recovery Facility (WRRF) solutions to worldwide customers for over 20 years. RUNNENG has over 30 professional experts and more than 150 staffs. Our high quality innovative wastewater equipment includes dissolved air flotation equipmentbar screen waste remover, sludge scraper and integrated sewage treatment equipment, etc. All our wastewater equipment has been passed the certificates of ISO9001, ISO14001 and OHSAS18001, we also have the Grade B engineering design certificate issued by the Ministry of Environmental Protection. Hope to be your partner.

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By |2018-12-17T14:30:09+00:00December 17th, 2018|Wastewater equipment cases|Comments Off on Cavitation Air Flotation Machine for Sewage Treatment in Refinery Factory

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