Selection of food waste wastewater treatment process

Food waste wastewater is organic wastewater with a high concentration, and its water quality will vary greatly depending on the type, scale, and season of the waste. According to the water quality analysis of similar projects, the general influent water quality is BOD/COD=0.3~0.6, with good biodegradability, and the biological treatment process can effectively treat most of the COD and SS in the sewage. Aiming at the characteristics of wastewater containing oil and high SS concentration, cyclone deoiler and air flotation are used to remove oil and SS in wastewater as pretreatment before wastewater biochemical treatment. Due to the high concentration of COD and ammonia nitrogen in wastewater, when the biological treatment process is adopted, since the wastewater contains more difficult-to-degrade organic matter, the COD value of the effluent after pretreatment and biological treatment can generally reach 600~800mg/L, and it is difficult to reach 500mg Below /L, restaurant waste wastewater is characterized by high pollutant concentration and high ammonia nitrogen content. The MBR treatment process is used to set up nitrification and denitrification treatment facilities, which can effectively remove COD and ammonia nitrogen.

Polyaluminium chloride.jpg

The MBR process is used for the treatment of kitchen waste wastewater. Due to the high sludge concentration, the volume of the treatment structure is greatly reduced, the project investment is low, the treatment effect is stable, and the cost performance is high. Comprehensive adjustment tank: The wastewater still contains a large amount of suspended solids and oil after anaerobic fermentation. To ensure the normal operation of the subsequent treatment process, the oil and suspended solids in the wastewater must be removed first. Therefore, before the wastewater enters the MBR treatment system, it first enters the cyclone deoiler, and then enters the air flotation tank to remove oil and large particles in the sewage. Air flotation tank: sewage flows into a small aeration section equipped with a releaser (or gas-liquid mixing pump), and the sewage is fully mixed by the microbubbles generated in the aeration section during the ascent process. Due to the density imbalance between the gas-water mixture and the liquid, a vertical upward buoyancy is generated, bringing the SS to the water surface. During the ascent process, the microbubbles will adhere to the SS, and after reaching the water surface, the SS will rely on these bubbles to support and maintain the water surface. The SS floating on the water is intermittently removed by the chain scraper. Biochemical system: The ultrafiltration part of the MBR system adopts an internal (external) ultrafiltration membrane module and an online cleaning system. The pretreated wastewater enters the biochemical tank, which is the internal (external) MBR biochemical treatment system. The MBR biochemical reactor consists of a pre-denitrification tank and a nitrification tank, both of which are secondary denitrification and nitrification processes. In the nitrification tank, through the action of highly active aerobic microorganisms, most of the organic matter is degraded, and the ammonia nitrogen and organic nitrogen are oxidized to nitrate and nitrite, which are returned to the denitrification tank and reduced to nitrogen in anoxic environment. To achieve the purpose of denitrification. In order to improve the utilization rate of oxygen, an efficient internal circulation jet aeration system is adopted, and the utilization rate of oxygen can reach 35%. The sludge reflux can make the sludge concentration in the biochemical reactor reach 15g/L. The microbial flora formed after continuous domestication can gradually degrade the organic matter that is difficult to biodegrade in the wastewater. The front denitrification reactor maximizes the use of carbohydrates present in wastewater. The removal rate of ammonia nitrogen in the nitrification and denitrification tank can reach more than 90%, the pollutant removal load is high, and the sludge concentration can reach 15g/L.

Related NEWS

  • 05-06-2021

    Analysis on the classification of industrial sewage treatment and industrial waste water

    Analysis on the classification of industrial sewage treatment and industrial waste waterIndustrial wastewater treatment technology should take into account the characteristics of industrial wastewater treatment. Industrial wastewater treatment is an important aspect of my country's industrial de

  • 04-12-2021

    Selection of PAM

    According to ionic characteristics, polyacrylamide can be divided into four types: non-ionic, anionic, cationic and amphoteric polyacrylamide. According to the molecular weight, there are different specifications of molecular weight, ion degree, etc., and many models are derived. Faced with the mark