Integration of thermo-vapor compressors with phenol and ammonia recovery process for coal gasification wastewater treatment system

Abstract

Current phenol and ammonia treatment process consumes a large amount of hot utilities to recover crude phenol and aqua ammonia, which includes 0.5 MPag steam (2.68 MW), 1.0 MPag steam (10.17 MW), and 2.5 MPag steam (1.97 MW) based on the benchmark treatment capacity of 100 t/h. This paper fixates on the further improvement of energy efficiency by process integration and innovation. A novel integrated process is proposed in this paper to abate utilities consumption. Two scenarios have been analyzed following the Grand Composite Curve. The results show that one of the new integrated processes performs better energy saving efficiency. It requires 53.7% (7.96 MWsteam) less hot utility consumption and 57.5% (6.86 MWcw) less cooling water consumption at the expense of 68.7% (662 kWelec) more electricity use, as suggested in simulation results. The estimated cost savings relevant to the improved process is 1.095 million US$/y, and the emission reduction is 5237 t CO2 e/y.