关键词: 气田水, 回注系统, 安全风险, 评价方法, 指标体系

Abstract:

Water reinjection system has four subsystems，including surface treatment station，water pipelines，reinjection
wellbore and reinjection layers. When a problem develops in any part of any subsystem，the whole water reinjection system
will be paralyzed or lead to great environmental pollution，but there is not a reliable，perfect risk assessment method of gas field
water reinjection system. In this paper，all failure factors and their evaluation standards of each subsystem are summarized，and
the weight of each index is determined according to the statistical results for failure frequency of each failure factor. Complete，
practical risk evaluation method for gas field water reinjection system and each subsystem was established through combining
with the influencing factors evaluation of leakage and referring to Kent risk evaluation model. Meanwhile，two kinds of safety
grade division standard were provided. This evaluation method includes both direct evaluation on the reliability of the system
and the evaluation of the leak consequence；it can not only be used to evaluate of each subsystem but also can be used to evaluate
the whole reinjection system by weighting evaluation results of each subsystem. The risk evaluation of reinjection system in
East Sichuan Gas Fields agree with the on-site observation，which has proved the feasibility of this risk assessment method.

Key words: gas field water, reinjection system, safety risk, assessment method, norm system