The sewage discharged from the slaughter industry contains a lot of pollutants such as blood, oil, fat, meat scraps, visceral debris, undigested food, feces and other pollutants. The content of suspended solids is high. The sewage is reddish brown and accompanied by a heavier fishy smell. . Slaughter wastewater has high organic content and good biodegradability, but high-concentration organic substances are not easily degraded, and random discharge can easily cause eutrophication of river water, cause ecological disasters, and pollute the air, so it is difficult to treat.
A large number of automated equipment has made the slaughter industry and the meat processing industry more and more effective. However, the development of the slaughter industry and the meat processing industry has also brought pollution to the environment because of the high content of organic suspended solids in the slaughter wastewater. Prone to corruption. If it is discharged into the water body without treatment, it will cause serious eutrophication of the surrounding water body, destroy the self-purification ability of the water body, make the water body black and smelly, destroy the ecosystem, and pollute the environment. Polyacrylamide, as an additive in all industries, has a very good effect on the treatment of slaughter wastewater, so the treatment of slaughter wastewater is not difficult. The role of polyacrylamide for slaughter wastewater treatment.
Because the slaughter wastewater has good biochemical characteristics, coagulation sedimentation and air flotation processes can be used to treat the suspended solids in the slaughter wastewater. After treatment, it can generally meet the discharge standard or be recycled. The role of polyacrylamide for slaughter wastewater treatment. There are many methods to treat this kind of sewage, and polyacrylamide can be used in both coagulation and hydrolytic acidification-biological adsorption regeneration-contact oxidation process.
The wastewater passes through the grille to remove the larger pollutants in the water, the sediment is oil-separated to remove the grease and scum in the sewage. The sewage and sludge are fully mixed through the primary sedimentation tank and the adjustment tank to play the role of hydrolysis and acidification, and then flow into the reaction tank to complete The process of aeration, oxidation, precipitation, decanting and discharge of excess sludge. At this time, by adding polyacrylamide and polyaluminum chloride for flocculation precipitation, the problem of high BOD5, CODcr and SS in water is solved. The decanted water enters the contact settler to remove fine suspended solids and grease. The remaining sludge in the pond is discharged into the sludge pond by the submersible sewage pump for concentration, and the supernatant liquid of the sludge pond returns to the regulating pond. In the treatment of the biochemical sludge section, cationic polyacrylamide is used to desludge the sewage, which can be regularly sucked away by a vacuum fertilizer truck and used as farm manure.
Coagulation: The use of coagulation to treat sewage is currently the most popular domestic sewage treatment method. Among them, the inorganic flocculant polyaluminum chloride has a better effect on the treatment of slaughter wastewater. Sometimes in order to increase the flocs and make the flocs more compact, a small amount of polyacrylamide is added as a composite polymer coagulant to extract the fruit. But before using the coagulant to treat the slaughter wastewater, it is better to use calcium oxide to saponify the oil and protein in the water, so that the polyacrylamide will have a better treatment effect. The coagulation method has low cost of wastewater treatment, and has good treatment effect at low temperature. It is mostly used for the pretreatment of low-concentration wastewater or high-concentration wastewater.
Hydrolysis acidification-biological adsorption regeneration-contact oxidation process This water treatment method adopts the AB two-stage combined process, the A stage has a high load, and the addition of polyaluminum chloride and polyacrylamide polymer flocculants with strong adsorption capacity makes flocs It has good settling performance, compact flocs, large volume, fast settling speed, and strong impact load resistance, but the amount of sludge is high, so corresponding sludge treatment measures need to be taken. A small amount of difficult-to-settling pollutants in the effluent of the second settling tank in section B. Our polyacrylamide manufacturer recommends further removal by air flotation treatment to improve the quality of the effluent and meet the discharge standards.
Slaughter wastewater is more common in the food processing industry, especially in the meat and seafood processing industries. It is a typical industrial wastewater with industry characteristics. People rely on food as the sky. Today’s society consumes huge amounts of meat and pork. For example, as the upstream of the supply chain, the meat food processing industry has huge production and processing capabilities. Due to special sanitation requirements during the meat food processing process, a large amount of slaughter wastewater will be generated during the production process, which has large changes in concentration and high organic content. Characteristics, direct discharge into the environment will severely pollute water bodies.
Generally, slaughter wastewater comes from the slaughter workshop, mainly including:
① Wash the waste water of livestock before slaughter;
②Scalding and carcass washing wastewater;
③Waste water for cleaning internal organs;
④ Scour the workshop floor and appliance waste water;
⑤ Flushing waste water from the fence, etc.
The slaughter water quality has the following characteristics:
①The slaughter wastewater is generally reddish-brown with an unpleasant fishy smell, which contains a large amount of blood, grease, hair, meat scraps, bone scraps, visceral debris, undigested food, feces and other dirt, with high solid suspended solids content .
②The slaughter wastewater has high organic content and good biodegradability. The high-concentration organic matter is not easily degraded and the treatment is difficult. The nutrients in the slaughter wastewater are mainly nitrogen and phosphorus. Among them, nitrogen mainly exists in the form of organic matter or ammonium salt, while phosphorus Exist in the form of phosphate.
③Contains coliform, fecal streptococcus and other pathogenic bacteria that are harmful to human health.
④ Water quality and water volume change quite a bit within a day.
The slaughter wastewater is generally biodegradable. Although the pollutant index is relatively high, after the solid impurities are removed through pretreatment such as coagulation sedimentation, air flotation and other processes, the biochemical treatment can generally reach the discharge standard. In the treatment of biochemical sludge Cationic polyacrylamide is used in the treatment section, and among these sludge dewatering agents, we generally choose flocculants with relatively high ionicity and molecular weight.
In addition to the above characteristics, some special slaughter wastewater such as seafood processing wastewater and donkey-hide gelatin wastewater have higher salt content, and sometimes the salt content even exceeds the capacity of biochemical treatment. For this type of wastewater, it is necessary to conduct experiments based on detailed water quality. To formulate a design plan, consider the use of physical and chemical methods such as catalytic oxidation process, low temperature distillation process, membrane separation process, etc. for more real situations. In this case, anionic or long and short ion PAM can be used, and the slaughterhouse wastewater treatment is more complicated. Generally, cations with an ion degree of more than 40 will be used.
Wastewater from farms and meat products factories mainly comes from feed wastewater, disintegration wastewater, visceral cleaning wastewater and animal manure wastewater.
The slaughterhouse meat product factory wastewater contains a lot of organic matter, and the wastewater is reddish brown with a strong fishy smell.
Flocculants for farm wastewater are better: it is recommended that slaughter wastewater be treated with cationic polyacrylamide, or a design plan can be made after specific water quality tests. For more extreme cases, consider the use of physical and chemical methods such as catalytic oxidation, cryogenic distillation, and membrane separation. For this type of sewage, if the treatment effect is not satisfactory or does not meet expectations, it is recommended to use strong cationic polyacrylamide or use it with other inorganic flocculants. The use of cationic polyacrylamide flocculant can effectively decolorize and flocculate this type of wastewater, reduce the probability of eutrophication of the surrounding water body, maintain the self-purification ability of the water body, and ensure the sanitation of environmental water bodies* and agricultural irrigation water. Polyacrylamide, polychlorine Chemical aluminum, PAC, PAM, etc. are expensive. If it is not a large-scale farm, please use it with caution.