Dairy wastewater generally contains fats, lactose, whey proteins, and nutrients. Casein precipitation causes the effluent to decompose into a dark, strong-smelling sludge. Fluid waste contains soluble organic matter, suspended solids, and gaseous organic matter, which cause undesirable taste and smell, grant tone and turbidity, and advance eutrophication, which plays an essential role in increasing biological oxygen demand (BOD) in water. It also contains detergents and disinfecting agents from the rinses and washing processes, which increase the need for chemical oxygen (COD). One of the characteristics of dairy effluents is their relatively high temperature, high organic contents, and wide pH range, so the discharge of wastewater into water bodies without treatment leads to deterioration of water quality and ecological imbalance, and therefore treatment is required. To remove or reduce environmental damage. Dairy wastewater treatment includes mechanical, physical, chemical, and biological methods.
Organic treatment techniques are reasonable for treating wastewater from the dairy business because of their high biodegradability. Notwithstanding, the long-chain unsaturated fats framed during lipid hydrolysis show an inhibitory impact during anaerobic treatment. Chain block reactors (SBR) and top stream anaerobic slop cover of sludge (UASB) frameworks are the most encouraging advancements for the organic treatment of dairy wastewater. Many papers have applied high-impact exercise and technical methods to the dairy business's anaerobic wastewater treatment of dairy wastewater. However, the two techniques actually have a few disadvantages. The most vital objective of these studies is to track down savvy and naturally manageable ways to deal with and empower the reuse and management of wastewater and waste. Consequently, elective treatments to organic treatment are physical and substance techniques, for example, coagulation, retention, layer cycles, and electrolysis. This section gives a primary survey zeroing in on physical and compound treatment strategies for dairy wastewater treatment. It is under study and checked for its viability.