Theory And Structure Research On Vacuum Belt Press Dehydrator Of Oil Sludge

Oil sludge is produced in the process of raw oil dehydrating in oil field corporations and oily sewage disposal in the petrochemical industry factories. Oil sludge which is black and brown, ropy ,smelly, with higher water ratio and larger volume, is dangerous solid wastes with poison. It will pollute environment seriously if they are thrown away randomly. The first step of oil sludge disposal is reducing its water ratio so that its volume becomes smaller. So it is necessary to research these theories and structure of oil sludge dehydrating equipment and has very important practical values in engineering.Vacuum belt filter and belt press filter are the usual equipments of oil sludge dehydrating. But they have respective virtues and shortcomings. The vacuum belt press dehydrator of oil sludge, as a new type of oil sludge dehydrating equipment, is based on these virtues of the two types of equipments. In this paper some key theories and structure about vacuum belt press dehydrator of oil sludge for the purpose of much higher dehydrating ratio.In this paper vacuum filtration theory, shearing and press theory with press roll, offset adjustment of belt principle are studied. Vacuum filtration belongs constant pressure filtration. According to the basic equation of constant pressure filtration, the effects of filtration time and pressure difference to water ratio of oil sludge are analyzed and the relational expression between filtration time and water ratio of oil sludge is deduced. On the basis of the basic press theory, shearing and press principle with press roll is analyzed and the pressure formula of press roll is deduced. Filtration belt is flexible part. It plays an important role in the working process. Its function is not only filtration and press but also dragging and loading. Because of its long operation period, manufacture and installation error, belt offset is inevitable. It is the key factor to affect the normal operation of vacuum belt filter and belt press filter. The reason of belt offset is analyzed in this paper. The conclusion drew is proved correctly by the practice. These theories researched above provide base of theory for properly allocating vacuum filtration time, assignment of press roll and the optimum design of roll's radius, the design of belt offset adjustment structure. These principles have important values in engineering.The structure of rolls, which has important effect on the last water ratio of oil sludge, is the core of Vacuum belt filter and belt press filter in the whole design. Inthis paper the structures of press roll, adjustment mechanics and flatten roll are designed properly. This type of structure avoids the overflow of sludge and belt offset as possible in the process of press.