(104bd) Multi-Objective Optimization of Hazardous Substance Storage Facilities. the Decision Between Risks and Costs Associated to the Project

When designing a hazardous substance storage facility, a lot of effort is put into planning the safety measures that it will require, like fire protection systems, insulation, or pressure relief valves; these devices, though very necessary and useful, sometimes do not perform as expected, either because of fails in maintenance, or because an accident renders them ineffective.

Recently, Medina et al. [1] demonstrated that it is possible to find an optimum number of tanks to store a certain mass of a dangerous substance; since the consequences of an accident are directly proportional to the mass of material involved, then it is possible to lower the consequences of accidents by using more tanks to store the same amount of substance. Therefore it is possible to find an optimum number of tanks that will represent the minimum risk for the facility by using quantitative risk analysis techniques coupled with optimization principles.

However, as more tanks are built, the costs associated to the project increase, and a new decision problem arises between improving the design risk-wise and lowering the costs associated to the project. In this work, a decision making tool based on multi-objective optimization is presented to solve this problem.

Multi-objective optimization is ideal to solve problems where a trade-off exists between different objectives; in the case presented in this work, there is a trade-off between the number of units to store, which is equivalent to the costs, and the risk associated to the project. The tool developed will allow observing the interaction between the two objectives, which will improve the decision making process at the moment of designing a storage installation of hazardous substances.

References:

[1] H. Medina, J. Arnaldos, J. Casal, (2009), Process design optimization and risk analysis, Journal of Loss Prevention in the Process Industry, 22 (2009) 566-573.