Design Tools for Chemical Process Safety: Accident Probability

EPA Grant Number: R825370C066
Subproject: this is subproject number 066 , established and managed by the Center Director under grant R825370
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).

Center: EERC - National Center for Clean Industrial and Treatment Technologies (CenCITT)
Center Director: Crittenden, John C.
Title: Design Tools for Chemical Process Safety: Accident Probability
Investigators: Crowl, D. A.
Institution: Michigan Technological University
EPA Project Officer: Klieforth, Barbara I
Project Period: January 1, 1997 through January 1, 1999
RFA: Exploratory Environmental Research Centers (1992) RFA Text |  Recipients Lists
Research Category: Center for Clean Industrial and Treatment Technologies (CenCITT) , Targeted Research

Objective:

The objective of this project is to provide design tools for including process safety in the conceptual design of chemical processes. In particular, this part of the effort will be directed towards providing design tools to estimate the probability of an accident, and how this can be coupled to a cash flow analysis.

Approach:

Previous CenCITT project efforts have developed computer-based methods to estimate the relative hazard associated with a chemical process and to estimate the capital loss (financial consequence) associated with a process accident. Since risk is comprised of both consequence and probability, the addition of a tool to estimate accident probability would provide the user with a greater capability to estimate risk.

The work plan is to provide a number of interactive computer-based programs to assist the conceptual designer in estimating the risk due to episodic accidents from the processing of flammable and toxic chemicals.

Risk is comprised of both accident consequence and probability. To date, a program to estimate the hazards and financial consequence of an accident involving toxic and flammable chemicals has been completed (Dow Fire and Explosion Index, Dow Chemical Exposure Index). The work will also develop a database module to provide failure rate data to the designer and to describe the failure modes for various pieces of equipment. Finally, a method for coupling the accident probability to a complete cash flow analysis for the process will be developed, including the financial effects of an accident. This would provide an estimate of financial risk due to an accident.

The approach for this project is to provide a number of interactive computer-based programs to assist the conceptual designer in estimating the risk due to episodic accidents from the processing of flammable and toxic chemicals.

Risk is comprised of both accident consequence and probability. To date, a program to estimate the hazards and financial consequence of an accident involving toxic and flammable chemicals has been completed (Dow Fire and Explosion Index, Dow Chemical Exposure Index). The work will also develop a database module to provide failure rate data to the designer and to describe the failure modes for various pieces of equipment. Finally, a method for coupling the accident probability to a complete cash flow analysis for the process will be developed, including the financial effects of an accident. This would provide an estimate of financial risk due to an accident.

The following activities have been completed on this project:
1) An implementation of the Dow Fire and Explosion Index and the Dow Chemical Exposure Index in an interactive Visual Basic environment has been completed. Final evaluation of this software (with implementation) will be competed by the end of the year. These indices are necessary to determine the relative hazard and financial consequences of an accident.
2) A database to provide failure rate data for various pieces of process equipment has been completed.
3) A database to provide failure mode information for major process equipment, such as tanks, reactors, distillation columns, etc. has been completed.
4) A Monte Carlo simulator has also been completed to include the probability of an accident in the cash flow analysis. The user enters the total capital loss, the business interruption loss, the day's outage, and the number (n) of simulations to run. The simulator builds n plants and operates them for 50 years each tracking the failures and the impact on the cash flow. At the completion, a histogram of net present values (NPV) is produced.

The simulator packages were applied to a natural gas liquids (NGL) plant. The results show that:
1) The Dow F&EI values alone show the greatest hazard in the storage areas, where the largest inventories of flammables occur. However, coupling the results to a cash flow analysis shows that the greatest financial impact on the NPV occurs with major pieces of in-line process equipment, where the greatest capital and business interruption losses occur.
2) The traditional method for including accidents in a cash flow analysis has been to calculate a continuous dollar loss determined by multiplying the failure probability times the total capital loss. The Monte Carlo analysis indicates that this method only works if the failure probability is low.
3) A general method for including episodic events in a cash flow analysis.

Expected Results:

Previous CenCITT project efforts have developed computer-based methods to estimate the relative hazard associated with a chemical process and to estimate the capital loss (financial consequence) associated with a process accident. Since risk is comprised of both consequence and probability, the addition of a tool to estimate accident probability would provide the user with a greater capability to estimate risk.

Publications and Presentations:

Publications have been submitted on this subproject: View all 1 publications for this subprojectView all 157 publications for this center

Supplemental Keywords:

Computing technology, technology for sustainable environment, environmental chemistry, chemical properties, physical property data, clean technology, environmental engineering, risk assessment, chemical processing, Monte Carlo simulator, occupational safety, cash flow analysis, health risk. Human exposure., RFA, Scientific Discipline, INTERNATIONAL COOPERATION, Ecosystem Protection/Environmental Exposure & Risk, Sustainable Industry/Business, cleaner production/pollution prevention, computing technology, Economics and Business, pollution prevention, Environmental Engineering, in-process changes, in-process waste minimization, industrial design for environment, industrial process design, chemical process safety, occupational safety, cleaner production, environmentally conscious manufacturing, green design, pollution prevention design tool, cash flow analysis, decision making, clean technology, physico-chemical properties, computer science, Clean Process Advisory System (CPAS), CPAS, industrial process, process modification, industry pollution prevention research, Monte Carlo simulator, information technology, innovative technology, industrial innovations, outreach and education, green technology, environmentally conscious design, decision support tool

Progress and Final Reports:

  • 1997
  • Final

  • Main Center Abstract and Reports:

    R825370    EERC - National Center for Clean Industrial and Treatment Technologies (CenCITT)

    Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
    R825370C032 Means for Producing an Entirely New Generation of Lignin-Based Plastics
    R825370C042 Environmentally Conscious Design for Construction
    R825370C046 Clean Process Advisory System (CPAS) Core Activities
    R825370C048 Investigation of the Partial Oxidation of Methane to Methanol in a Simulated Countercurrent Moving Bed Reactor
    R825370C054 Predictive Tool for Ultrafiltration Performance
    R825370C055 Heuristic Reactor Design for Clean Synthesis and Processing - Separative Reactors
    R825370C056 Characterization of Selective Solid Acid Catalysts Towards the Rational Design of Catalytic Reactions
    R825370C057 Environmentally Conscious Manufacturing: Prediction of Processing Waste Streams for Discrete Products
    R825370C064 The Physical Properties Management System (PPMS™): A P2 Engineering Aid to Support Process Design and Analysis
    R825370C065 Development and Testing of Pollution Prevention Design Aids for Process Analysis and Decision Making
    R825370C066 Design Tools for Chemical Process Safety: Accident Probability
    R825370C067 Environmentally Conscious Manufacturing: Design for Disassembly (DFD) in De-Manufacturing of Products
    R825370C068 An Economic Comparison of Wet and Dry Machining
    R825370C069 In-Line Copper Recovery Technology
    R825370C070 Selective Catalytic Hydrogenation of Lactic Acid
    R825370C071 Biosynthesis of Polyhydroxyalkanoate Polymers from Industrial Wastewater
    R825370C072 Tin Zeolites for Partial Oxidation Catalysis
    R825370C073 Development of a High Performance Photocatalytic Reactor System for the Production of Methanol from Methane in the Gas Phase
    R825370C074 Recovery of Waste Polymer Generated by Lost Foam Technology in the Metal Casting Industry
    R825370C075 Industrial Implementation of the P2 Framework
    R825370C076 Establishing Automated Linkages Between Existing P2-Related Software Design Tools
    R825370C077 Integrated Applications of the Clean Process Advisory System to P2-Conscious Process Analysis and Improvement
    R825370C078 Development of Environmental Indices for Green Chemical Production and Use