RECOVERY OF WASTE OINTMENTS BY ULTRAFILTRATION METHOD

Abstract

Ultrafiltration devices are currently being developed and manufactured around the world, and productivity varies greatly from 1 to 300,000 m/day. In practice, ultrafiltration parameters are used and performed in batch, semi-periodic and continuous modes. Continuous and semi-periodic modes are mainly used for large volumes of liquids. In the case of a small volume, the batch mode prefers the continuous mode - the area of the membrane is smaller and it is easier to clean. The deposition of spent grease is based on the fact that mechanical impurities and water are in a suspended state and settle over time. When selecting the process of restoring the quality of the lubricant to the required level, first use a mechanical cleaning method to remove free water and hard dirt. In practice, rough cleaning of the lubricant is carried out using filter elements made of metal mesh with a filtration fineness of 60 ... 80 μm. A complex filter element made of non-woven materials is used for fine cleaning. Type of oil filter "FMN" (cleaning accuracy 15 ... 20 microns). However, these filters cannot provide a degree of purification of the spent lubricant, as the latter contains a large amount of carbon contaminants, preferably with a particle size of less than 5 μm. In the process of ultrafiltration of oil, the initial stream is separated and concentrated. Varnish, resin and other small contaminants are retained by the superporous layer on the surface and are continuously washed away by a tangential flow of purified oil. Only cleaned grease can pass through the membrane. This allows for a long filtration process without replacing the membrane filter element. The ultrafiltration process is performed at a pressure of 0.3-1 MPa and a flow rate of 2-5 m/s, using membranes with a size of 0.1-0.005 μm.