节水新技术在长庆石化公司的应用

The Application of New Water Saving Technology in PetroChina Changqing Petrochemical Company

长庆石化先后建设两套70m3/h初级再生水深度处理回用装置、一套60m3/h反渗透浓水回用装置和一套80m3/h凝结水除油除铁装置,采用的超滤、反渗透、陶瓷超滤等新技术,具有装置分离效果好、占地面积小、操作简单、安全环保等优点,应用"超滤+反渗透"双膜系统,其污水水质逐步改善,浊度明显下降,由过去的平均25NTU,下降为8NTU,实现了废水回用,有利于循环水系统的长周期运行,特别在减少换热设备腐蚀和黏泥生成,延长换热设备寿命、提高换热效率上有突出作用;浓水反渗透及二级除盐水系统的建立,实现了废水高等级回用,在同等工况下,2008年与2007年相比,除盐水消耗量平均减少1663t/d;应用无机陶瓷滤膜技术,又在实现废水高等级回用的同时,将其热能一并回收利用,真正达到高水高用的目的。几套装置合计投资为991万元,新增收益合计为680.2万元,投资收益比为0.69,投资回收期在2a以内。应用上述工艺处理后的废水,分别用作循环水系统、空冷装置和工业锅炉的补充水,吨油耗水从2002年的1.08t/t,下降为2010年的0.58t/t。

PetroChina Changqing Petrochemical Company has installed two 70m3/h primary regenerated water deep-processing and recycling units,one 60m3/h reverse osmosis enriched water recycling unit and one 80m3/h condensate water deoiling and deferrization unit.These units using new hyper-filtration,reverse osmosis and ceramic hyper-filtration technologies have good unit separation effects,do not occupy much area and are easy to operate and safe and environmentally friendly.With the use of hyper-filtration plus reverse osmosis dual-membrane system,the quality of the sewage has gradually improved and the turbidity has dropped significantly（from an average of 25NTU to 8NTU）,allowing for the reuse of waste water.This is instrumental to the long-term operation of the circulating water system.Particularly,the dual-membrane system plays a key role in reducing corrosion and slime generation in heat exchangers,extending the life of heat exchangers and raising heat exchange efficiency.The establishment of the enriched water reverse osmosis and secondary water desalting system enables the high-level recycle of waste water.Under the same working conditions,in 2008,the consumption of desalted water dropped by 1663t/d over 2007.The application of inorganic ceramic filter membrane technology enables the recycle of heat from waste water on top of the high-level recycle of waste water.Investment in these units totals 9.91 million yuan and new returns on the investment amount to 6.802 million yuan.The ratio of returns on this investment is 0.69.The investment will be recovered within two years.Waste water treated using the above technologies is used by Changqing Petrochemical as make-up water to feed the circulating water system,air cooling units and industrial boilers.The company′s water consumption in producing one ton of oil dropped to 0.58t/t in 2010 from 1.08t/t in 2002.