An MILP model for safe multi-floor process plant layout using the domino hazard index

Abstract

In this paper, an optimisation-based approach to obtain safe multi-oor process plant layout designs using the Domino Hazard Index (a sub-index of the Integrated Inherent Safety Index) is presented. A mixed integer linear programming (MILP) model is proposed to obtain the economically optimal multi-oor layout design considering connection by pipes, horizontal and vertical pumping of process uids, purchase of land, xed and area-dependent construction of oors, the nancial risk associated with hazardous events and their escalation potential, and the installation of passive protection devices. Hazardous events such as pool res, jet res, ash res, reballs and blast waves resulting from explosions are considered using a novel and more realistic estimation of safety distances between equipment items. A bi-objective optimisation problem is also considered, minimising the layout costs and the total domino hazard index values for the plant, adopting the -constraint method. The proposed model is then applied to an 11-unit case study susceptible to each of these hazardous events, obtaining results with the optimal layout and protection device congurations in a relatively short amount of time.

Multi-objective optimisation for safe multi-floor process plant layout using the Dow’s Fire & Explosion Index

“…Tugnoli et al (2008b) first applied the DHI to assess safety levels of different layout configurations, but de Lira-Flores et al ( 2014) developed an MINLP model to handle single floor cases. Ejeh et al (2021) further extended such model to account for multi-floor cases via single and bi-objective MILP models. These models accounted for pool fires, jet fires, fireballs, flash fires and explosions, and the effect such incidents had on other equipment as a function of separation distances and the presence of protection devices.…”

“…The proposed mathematical model presented is a modified form of the MILP model presented by Ejeh et al (2021) (summarised in Appendix A) for safe multi-floor process plant layout using the Domino Hazard Index (DHI) and an extension of the considerations of Patsiatzis et al (2004) to multi-floor process plants. Constraints are modified to evaluate the areas of exposure for pertinent process equipment and the associated MPPD with/without the availability of protection devices.…”

“…Distance constraints for connected equipment items (i ∈ I c ) are as described by Ejeh et al (2021) with eqs. (A.16) -(A.19) in Appendix A.…”

“…It is common practice that safety analysis, and the layout configuration, of chemical process plants are carried out after the detailed design of such plants are completed (Ortiz-Espinoza et al, 2021). This leaves little or no room for design modifications to improve on the overall safety levels of the plant which can lead to fatal consequences, disruption of production activities, and irreparable losses to the plant and neighbouring environment (Ejeh et al, 2021). From a safety point of view, this has led to the incorporation of inherent safety principles at the design stages of chemical process plants ( Khan and Amyotte, 2004).…”

Estudo Do Gerenciamento De Risco Envolvendo Incêndio Em Estruturas Industriais E Comerciais: Uma Revisão Sistemática Da Literatura

“…ElMeouche et al (2020) analisaram estruturas probabilísticas de risco de incêndio para otimizar o layout de canteiros de obra Ejeh et al (2021). utilizaram um modelo de programação linear inteira mista para propor layouts seguros de plantas de processos de vários andares usando o índice associado a um efeito cascata.…”