Experimental study on energy consumption of mechanical vapor recompression evaporation method for recovery of water from oily wastewater

Direct reinjection and discharge of water mixed with oil leads to environmental pollution and exhaust heat waste. Of the various methods used to treat wastewater, the mechanical vapor recompression (MVR) evaporation method has obvious advantages in energy consumption and environmental protection. In this paper, the use of MVR for water recovery from water co-produced with oil was studied and analyzed through experimentation. Based on the design calculations for the MVR system, the MVR rig was set up and a series of experimental studies were conducted. The results show that when keeping the suction pressure constant at 0.035 MPa, the compressor power increases with the increase of discharge pressure. The experimental value of the compressor power was slightly greater than the theoretical value, with a deviation of less than 5%. The amount of distilled water produced rose slightly when the compressor discharge pressure was increased. The power consumption for producing 1 m3of distilled water increased with the increase of discharge pressure, which is also in accordance with the design condition. The experimental value of the power consumption per unit of distilled water is larger than the theoretical value, but the deviation is within 10%.