The Development Of Physical Method For OIL Removal And Cleaning Agent For Equipment To Coal Chemical Industry Wastewater

In the coal conversion process, a large amount of oily wastewater are produced. The oil can cause adverse effects on the operating performance of the subsequent processing and COD of the effluent, therefore the oil must be removed from the wastewater. Oil has a wide density distribution and part of the oil is emulsified state in the wasterwater, so it is difficult to achieve a satisfying treatment effect through the conventional physical sedimentation and centrifugal separation, and coagulation precipitation and flotation have an unstable effect and can interfere with the subsequent membrane treatment process. A degreasing method of high efficiency and low side effects is in urgent need.In this paper, a efficient oil extraction process is used to reduce the pollution load of wastewater. The results show that the requirement of oil extraction can be reached in the phase ratio of 1:4. In the case, the removal efficiency is up to 90% and could relieve the problem caused by device fouling because of oil. For the oily wastewater oil extraction is a new method of oil and water separation because of many significant advantages such as good degreasing effect, recycled extracting agent and recycled the oil of the water. The distillation separeation process of oil and extracting agent is simulated by Aspen plus software and the result show that the requirement can be achieved.Aiming at the sediments which are deposited when wastewater flows through the equipment in the chemcal industry, we develop a cleaning agent with a good cleaning ability. Taking water as solvent, this cleaning agent adds appropriate amount of surfactant with 1% AEO-9,3% AES, and 4% OP-10, high boiling organic solvent with 20%2-Butoxy ethanol and cleaning assistant agent with 3% sodium tripolyphosphate, 0.5% silicate and appropriate sodium hydroxide. The solubility is 75% through performance evalution experiments. Industrial tests indicate that the cleaning agent has the advantages of good ability in removing the scale. The sediments in the equipment could be removed thoroughly after 5 hours of cleaning with an online cleaning device.