Novel Method for Optimizing Emergency Response Facility Layouts in Gas Pipeline Networks

Effective management of gas accidents requires the rapid deployment of responders and resources from emergency response facilities to accident sites. In this study, a three-level optimization methodology of emergency response facility layout in a gas pipeline network is proposed. A set covering model is firstly established to determine the number of emergency response facilities. Meanwhile, the coverage regions are adjusted based on response timeliness, workload balance, and pipeline integrity. Then, a theoretical optimization model is developed to minimize the distance between the emergency response facilities and the gas accident hot spots (i.e., historical emergency points and high-consequence points). Finally, an adaptability evaluation model is constructed to determine the actual layout of the emergency response facilities according to the comprehensive index system, the analytic hierarchy process (AHP), and the technique for order preference by similarity to the ideal solution (TOPSIS). This methodology is applied to a typical gas pipeline network located in Chengdu, China. The results showed that the number of emergency response facilities could be reduced from 21 to 5 with a coverage radius of 13 km. It indicates that the emergency response costs could be decreased from the original CNY 5.25 million to 1.25 million per year, a reduction of 76.2%. In addition, the maximum response times of five different emergency response facility during the off-peak traffic period are 28, 26, 30, 29, and 23 min, respectively, and those during the peak traffic period are 42, 33, 41, 36, and 31 min, respectively, which could both be acceptable. Consequently, this method could greatly optimize the number, efficiency, costs, and loss prevention capability of emergency response facilities. It could further be applied to other fields, such as oil, mining, and chemical engineering.