The normal operation of meat processing plants produces a warm wastewater with naturally high levels of COD, total nitrogen and phosphorus, total suspended solids and fats, oils and grease. The removal of these excessive fats, oils and grease is important prior to subsequent biological treatment. Furthermore, as the industry moves towards more sophisticated biological treatment processes, the removal of oil and grease (O&G) is becoming increasingly important in order to avoid severe operational problems. The industry also faces increasingly stringent regulations for waste disposal, together with intensification of meat processing.

To date, the most effective and most widely used process for achieving near complete removal of O&G from raw wastewater has been dissolved air flotation. Hydrocyclones are another technology that may offer significant benefits for the removal of O&G from wastewater streams and have recently been introduced to the meat processing industry in Australia, with approximately 5 – 6 units being installed in the past 18 – 24 months.