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Inherent Safety (inherent + safety)

Distribution by Scientific Domains
Chemistry100%

Selected Abstracts

Evaluation of available indices for inherently safer design options

PROCESS SAFETY PROGRESS, Issue 2 2003
Faisal I. Khan
Inherent safety is a proactive approach for loss prevention during process plant design. It has been proven that, considering the lifetime costs of a process and its operation, an inherent safety approach can lead to a cost-optimal option. Application of inherent safety at the early stages of process design yields the best results with respect to process selection, conceptual design, and engineering design. However, in spite of being an attractive and cost-effective approach to loss prevention, it is not widely used. Reasons have been suggested for this lack of widespread use, but the lack of systematic tools to apply inherent safety principles is perhaps the most important one. A detailed study was conducted to analyze the performance of available hazard indices with reference to various inherent safety principles (guidewords). The performance of four main indices (Dow, Mond, Inherent Safety, and Safety Weighted Hazard [SweHI] indices) was studied for five inherent safety guidewords. None of the indexing procedures can capture all of the inherent safety guidewords, although the SWeHI and Dow Index were found to be robust on many accounts. It is recommended that a new specific index be developed for inherently safer design evaluation. The SWeHI and Dow indexing procedures may be a good basis on which to build. [source]

Game theoretic approach to multiobjective designs: Focus on inherent safety

AICHE JOURNAL, Issue 1 2006
Anjana Meel
Abstract A method for designing processes that are inherently safer,with the primary focus on disturbances having the potential for unbounded hazardous responses,is introduced. In cases where safety is not threatened (as in isothermal fermentation reactors), but product quality can rapidly degrade, this method provides designs that ensure high product quality (as in pharmaceutical processes). Using game theory, the method accounts for the trade-offs in profitability, controllability, safety and/or product quality, and flexibility. For nonlinear processes that are hard to control; that is, have an unstable and/or nonminimum-phase steady state, over a wide range of operating conditions, extended bifurcation diagrams are introduced. When a steady state is nonminimum phase, the process may exhibit inverse response. The steady states of processes are classified on the basis of instability and nonminimum-phase behavior to segregate the operating regimes into distinct zones. Locally optimal designs, one corresponding to each zone, are obtained first. These are compared with other locally optimal designs at alternate operating conditions, and/or process reconfigurations, to obtain the globally optimal design using game theory. Four indices,profitability, controllability, safety and/or product quality, and flexibility,characterize the optimality of a design. A novel index for safe operation and/or product quality at a steady state is formulated as a function of the eigenvalues of the Jacobian of the process model and the Jacobian of the process zero dynamics, providing a quantitative measure of instability and nonminimum-phase behavior. The application of the proposed method to an isothermal, continuous stirred-tank reactor (CSTR) with van der Vusse reactions, an exothermic CSTR, and an anaerobic fermentor with substrate and product inhibition is presented. © 2005 American Institute of Chemical Engineers AIChE J, 2006 [source]

Incorporation of inherent safety principles in process safety management

PROCESS SAFETY PROGRESS, Issue 4 2007
Paul R. Amyotte
Abstract Process safety management (PSM) deals with the identification, understanding, and control of process hazards to prevent process-related injuries and incidents. Explicit incorporation of the principles of inherent safety in the basic definition and functional operation of the various PSM elements can help to improve the quality of the safety management effort. Numerous inherent safety examples, both technical and nontechnical, are given in this paper. Existing qualitative and quantitative tools that already include, or could incorporate, inherent safety are described. Recently developed inherent safety tools for quantitative hazard identification and assessment are identified from either the literature or the current authors' work. Qualitative protocols for incorporating inherent safety into PSM elements are also presented. The language of inherent safety, although largely unused in PSM documentation, has a key role to play in enhancing the effectiveness of PSM. © 2007 American Institute of Chemical Engineers Process Saf Prog 2007 [source]

Definition of inherent safety

PROCESS SAFETY PROGRESS, Issue 4 2006
David Moore PE
No abstract is available for this article. [source]

Definition of inherent safety

PROCESS SAFETY PROGRESS, Issue 4 2006
Arthur M. (Art) Dowell III PE
No abstract is available for this article. [source]

Chemical plants , inherent safety

PROCESS SAFETY PROGRESS, Issue 4 2006
Dennis Hendershot
No abstract is available for this article. [source]

Evaluation of available indices for inherently safer design options

PROCESS SAFETY PROGRESS, Issue 2 2003
Faisal I. Khan
Inherent safety is a proactive approach for loss prevention during process plant design. It has been proven that, considering the lifetime costs of a process and its operation, an inherent safety approach can lead to a cost-optimal option. Application of inherent safety at the early stages of process design yields the best results with respect to process selection, conceptual design, and engineering design. However, in spite of being an attractive and cost-effective approach to loss prevention, it is not widely used. Reasons have been suggested for this lack of widespread use, but the lack of systematic tools to apply inherent safety principles is perhaps the most important one. A detailed study was conducted to analyze the performance of available hazard indices with reference to various inherent safety principles (guidewords). The performance of four main indices (Dow, Mond, Inherent Safety, and Safety Weighted Hazard [SweHI] indices) was studied for five inherent safety guidewords. None of the indexing procedures can capture all of the inherent safety guidewords, although the SWeHI and Dow Index were found to be robust on many accounts. It is recommended that a new specific index be developed for inherently safer design evaluation. The SWeHI and Dow indexing procedures may be a good basis on which to build. [source]