摘要
Abstract
As a high-energy-consuming unit in refineries,sour water stripping units account for approximately 6.5%of the total energy consumption and 4%of the carbon emissions of a refinery.This paper focuses on the operation status of a dual-tower pressurized stripping unit in a specific refinery.Through an in-depth analysis of the mechanisms by which key process parameters,such as temperature gradients,system pressure,cold feed,and ammonia nitrogen concentration,affect steam consumption,By increasing the final heat exchange temperature of raw water by 12.7℃,the steam consumption is reduced by 2.52 t/h.By optimizing the cold feed rate of hydrogen sulfide stripper and the top recovery of ammonia stripper,and the steam consumption is further reduced by 0.61 t/h.The transformation to a singletower pressurized side-line ammonia extraction process is expected to save 0.072 t of steam per ton of water.A heat pump system for the ammonia stripping tower is added to utilize the latent heat of the overhead ammonia gas,which can save 20 t/h of steam.High-efficiency heat exchangers are replaced to increase the final temperature of raw water heat exchange to 135℃.After comprehensive optimization,the energy consumption of the unit is reduced by 14.01%,with an annual steam saving of 26,300 tons,carbon reduction of 8,269 tons,and annual cost reduction of 5.38 million yuan.The investment payback period of the heat pump system is only 1.31 years.The research provides an effective path for energy saving and carbon reduction of high-concentration sulfur-containing wastewater treatment,and helps the refinery achieve the"dual carbon goals".关键词
污水汽提装置/蒸汽消耗/优化/技术改造/热泵系统/双碳Key words
sour water stripping units/steam consumption/optimization/technical transformation/heat pump system/dual carbon分类
能源科技
