We present a Mixed Integer Non-Linear Programming (MINLP) model capable of choosing the best design considering economic profit, availability, and safety. The model takes into account the probability of suffering a failure in a year of operation, as well as the revenue generated and the probability of the process units of being in a non-functional state. The inclusion of programmed maintenances of a specified duration is considered in the model, assuming an equal distribution in the maintenances time. The performance of the model is illustrated by small examples to help the reader to better understand the model, before applying it to the methanol synthesis case study, where the economic and safety objectives are represented in a Pareto front. The results showcase the possibility of considering safety during the early design stage.

我们提出了一种混合整数非线性编程（MINLP）模型，该模型能够考虑经济效益，可用性和安全性来选择最佳设计。该模型考虑了在一年的运营中遭受故障的可能性，以及所产生的收益和过程单元处于非功能状态的可能性。在模型中考虑了指定持续时间的计划维护，假设维护时间分布相等。通过小例子说明模型的性能，以帮助读者在将模型应用于甲醇合成案例研究之前更好地理解该模型，在该案例中，经济和安全目标以帕累托曲线表示。结果表明在设计的早期阶段就可以考虑安全性。