基于LCA的两种油田采出水处理工艺环境影响负荷对比研究

发布时间：2018-06-01 23:12

本文选题：生命周期评价 + CML2001　；参考：《哈尔滨工业大学》2015年硕士论文

【摘要】：随着我国几大主力油田逐渐进入石油开发的中后期阶段,采油过程中随之产生的油田采出水数量也逐渐增多,因此,对油田采出水处理的需求也逐渐增大。油田采出水处理工艺在其建设期、运营期和报废期均会产生一定的废水、废气与固体废物,对环境产生不利影响,故而在后续的工程实践中如何选择对环境更加友好的处理工艺也变得更加重要。不同于传统评价方法单一从经济效益和处理效果的角度去考虑问题,生命周期评价因将其视角聚焦在某一产品系统所产生的综合环境影响上,得到了广泛的关注。为了探究不同油田采出水处理工艺的环境影响负荷的差异,本文选择生命周期评价的方法对针对相同进出水标准的两种常用油田采出水处理工艺的环境影响负荷进行研究。本文选择大庆油田中十四污水处理站和中十六污水处理站为研究对象,从不同生命周期阶段和不同环境影响类型两个层面比较了两种工艺在运营年限为20年时的环境影响负荷差异,并分析相应的原因。最后基于生命周期评价进行了两种工艺的碳足迹对比分析,为后续工程实践的工艺选择提出了建议。研究结果表明,运营年限为20年时,中十六污水处理站的全生命周期环境影响负荷为中十四污水站的1.29倍,主要原因为中十六污水处理站运营期产生的环境影响负荷为于中十四污水处理站的1.86倍。并且随着运营年限的增加,二者的差值还会继续增大。从不同环境影响类型的角度来考虑,中十四污水处理站在全生命周期内对外界环境影响最大的为人类毒性潜能,为1.25×10-5,占其总环境影响负荷的62.00%。中十六污水处理站在全生命周期内对外界环境影响最大的为人类毒性潜能,为1.44×10-5,占其总环境影响负荷的55.56%,其他类型的环境影响负荷对总体的贡献均不足20%。从生命周期阶段的方面来考虑,在中十四污水处理站的各阶段中,对环境影响最大的为运营阶段,该阶段环境影响负荷为1.18×10-5,为其总体环境影响的58.76%。而对于中十六污水处理站,对环境影响最大的也是运营阶段,该阶段环境影响负荷为2.20×10-5,占其总体环境影响的84.66%。碳足迹分析结果表明,中十四污水处理站在建设阶段和报废阶段产生的碳足迹大于中十六污水处理站,但当运营年限超过3年时,中十六污水处理站的全生命周期碳足迹便会超过中十四污水处理站。因此,从碳足迹角度考虑,在能满足处理需求的情况下,在两种常用的处理工艺中,本文推荐中十四污水处理站采用的“自然沉降—混凝沉降—核桃壳过滤”工艺。本文对于油田采出水处理工艺的可持续发展具有重要意义,研究结果从环境影响的角度为后续工程实践提供了借鉴。
[Abstract]:With the major oil fields in China gradually entering the middle and late stage of oil development, the amount of produced water produced in the oil production process is also gradually increasing, therefore, the demand for the treatment of produced water in oil fields is also gradually increasing. The treatment process of oilfield produced water will produce certain waste water, waste gas and solid waste during its construction, operation and end-of-life, which will have a negative impact on the environment. Therefore, in the subsequent engineering practice, how to choose a more environmentally friendly treatment process has become more important. Different from the traditional evaluation method which only considers the problem from the angle of economic benefit and treatment effect, life cycle evaluation has been widely concerned by focusing its perspective on the comprehensive environmental impact of a product system. In order to explore the difference of the environmental impact load of different oilfield recovery water treatment processes, this paper chooses the method of life cycle evaluation to study the environmental impact load of two common oilfield production water treatment processes with the same water inlet and outlet standards. In this paper, Zhong14 sewage treatment station and 16 sewage treatment station in Daqing Oilfield are selected as the research objects. The difference of environmental impact load between the two processes with 20 years of operation was compared from two aspects of different life cycle stages and different environmental impact types, and the corresponding reasons were analyzed. Finally, based on the life cycle evaluation, the carbon footprint of the two processes is compared and analyzed, and some suggestions for the process selection of the subsequent engineering practice are put forward. The results show that, when the operating life is 20 years, the whole life cycle environmental impact load of Zhongxi sewage treatment station is 1.29 times of that of Zhong14 sewage treatment station. The main reason is that the environmental impact load of the sewage treatment station is 1.86 times of that of the wastewater treatment station. And with the increase in the number of years of operation, the difference between the two will continue to increase. From the point of view of different environmental impact types, the maximum environmental impact on the environment of Zhong14 sewage treatment Station is human toxicity potential, 1.25 脳 10 ~ (-5), which accounts for 62.00% of the total environmental impact load in the whole life cycle. In the whole life cycle of the sewage treatment station, the human toxicity potential is 1.44 脳 10 ~ (-5), which accounts for 55.56% of the total environmental impact load, and the contribution of other kinds of environmental impact load to the whole environment is less than 20%. From the aspect of life cycle stage, the operation stage is the most important one in each stage of middle 14 sewage treatment station. The environmental impact load of this stage is 1.18 脳 10 ~ (-5), which is 58.7665 of its overall environmental impact. However, the most important environmental impact is the operation stage, which is 2.20 脳 10 ~ (-5), which accounts for 84.66% of the total environmental impact. The results of carbon footprint analysis show that the carbon footprint produced by the sewage treatment station of No. 14 is larger than that of the sewage treatment station at the stage of construction and abandonment, but when the operating life is longer than 3 years, The full life cycle carbon footprint of the Secondary 16 sewage treatment Station will exceed that of the Secondary 14 sewage treatment Station. Therefore, considering from the point of view of carbon footprint, under the condition that can meet the needs of treatment, in the two common treatment processes, this paper recommends the process of "natural sedimentation-coagulation sedimentation-walnut shell filtration" adopted in the wastewater treatment station of No. 14. This paper is of great significance for the sustainable development of oilfield recovery water treatment process, and the research results provide a reference for the subsequent engineering practice from the point of view of environmental impact.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X741;X82

【参考文献】