炼油污水“三泥”减量化处理技术探讨

广州石化公用工程部炼油污水处理装置,原“三泥”处理单元,采用的是上世纪90年代生产的带式压滤机,工艺比较落后,设备老化严重,“三泥”处理能力及处理效果已不能满足生产要求,直接影响到炼油污水处理装置外排污水的稳定达标.通过对现有“三泥”处理单元进行技术改造,将带式压滤机更换成离心脱水机:并通过源头减量化控制、筛选污泥脱水絮凝剂等工艺优化措施,解决了炼油千万吨改扩建后污水处理装置“三泥”产量增大,带式压滤机处理能力不足,脱水后干泥含水率偏高,“三泥”直接外运,处理费用高等难题,使现有的“三泥”处理单元能满足炼油污水处理装置的正常生产需要,基本实现污泥脱水的减量化处理,炼油污水处理装置外排污水合格率也相应提高.广州石化炼油污水处理装置工艺改造中,增上了一套“三泥”热萃取装置,待其调试开工后,经热萃取处理系统处理后的产物的含水率将小于5％,可送至CFB锅炉直接焚烧,将真正实现污泥的减量化、资源化和无害化处理.

A Discussion on Technologies for Reducing Sludge in Refinery Sewage

Sinopec Guangzhou Company′s refinery sewage treatment plant originally used a belt filter manufactured in the 1990s in its sludge treatment unit.Due to the use of outdated technology and the aging of equipment,the plant′s sludge treating capacity and effect were unable to meet demand from production and this had directly impacted the quality of effluent from the refinery sewage treatment plant.Through a technological upgrade on the existing sludge treatment unit,the problems with the sewage treatment plant,which popped up since a 10mt/a refining capacity expansion,were resolved,including increased sludge output,insufficient capacity of the belt filter,high water cut of dehydrated dry sludge and high cost of refinery sludge processing outsourcing.The measures taken in the upgrade included replacing the belt filter with a centrifugal dehydrator,controlling the production of sewage at the source and using the appropriate sludge dewatering flocculant.As a result of the optimization,the existing sludge treatment unit is again able to meet the demand for treating refiner sewage and the amount of sludge that needs to be hydrated is reduced.The percentage of effluent meeting discharge requirements from the refinery sewage treatment plant has also increased.In the technological upgrade on the refinery sewage treatment plant,Sinopec Guangzhou Company added a sludge hot extraction unit to the plant.The water cut of the products treated in the hot extraction process is lower than 5% and the products can be sent to the CFB boiler for direct incineration.The refinery sludge has therefore become a useful resource.