ABSTRACT
Dairy plants process a wide variety of products including milk, cheese, butter, ice cream, yogurt, nonfat dry milk, whey, and lactose. The volume and composition of dairy wastes from each plant depends on the types of products produced, waste minimization practices, types of cleaners used, and water management in the plant. Because most dairy plants process several milk products, waste streams may vary widely from day to day. The main source of dairy effluents are those arising from the following:
1. Spills and leaks of products or by-products 2. Residual milk or milk products in piping and equipment before
cleaning 3. Wash solutions from equipment and floors 4. Condensate from evaporation processes 5. Pressings and brines from cheese manufacture
Dairy plant operators may choose from a wide variety of methods for treating dairy wastes from their plants. This may range from land application for small plants to operation of biological wastewater treatment systems for larger plants. Some dairy plants may pretreat the effluents and discharge them to a municipal wastewater treatment plant. Dairy wastes are segregated and treated separately from sanitary wastes generated in employee facilities. The objectives of treating dairy wastes are to (a) reduce the organic content of the wastewater, (b) remove or reduce nutrients that could cause pollution of receiving surface
waters or groundwater, and (c) remove or inactivate potential pathogenic microorganisms or parasites.
