DEVELOPMENT OF A PROCESS SECURITY ASSESSMENT TOOLBOX FOR CHEMICAL REACTION SYSTEMS

1. DEVELOPMENT OF A PROCESS SECURITY ASSESSMENT TOOLBOX FOR CHEMICAL REACTION SYSTEMS Cristina Piluso, Korkut Uygun, and Yinlun Huang Department of Chemical Engineering and Materials Science, Wayne State University Security Assessment Page Abstract Chemical processes are operationally more risky, environmentally more harmful, and potentially more dangerous than other types of manufacturing activities when abnormal or destructive situations arise. In the extreme, explosions, toxic release, and loss of life will occur rapidly, particularly when an adversary who has sufficient technical background on chemical operations makes a premeditated attack. Obviously, such security threatening situations must be swiftly detected, the possible impacts on production must be precisely evaluated, and operational solutions must be quickly derived. The mathematical framework for the Fast Process Security Assessment theory is the -analysis technique (Uygun et al., AIChE J., 49(9), 2445, 2003). In the theory, a process is defined as “secure” if the time needed to detect the threat and take the essential countermeasures to eliminate the threat is less than the time it takes for the system to reach disaster conditions, assuming the worst conditions. The -analysis is to examine directly the gradient of time derivative equations of a plant dynamic model, rather than integrating them that is very time consuming. This allows quick estimation for the minimum time that the process can go to disaster under a security threat. The estimation yields lower and upper bounds on the actual time the process will take to go to disaster, which are named process critical time and security limit time, respectively. In this work, a MATLAB-based process security assessment tool is developed for educational as well as limited industrial use. The software allows the user to define a customizable reactor system and analyze its security. Based on the Fast Process Security Assessment Theory, the software enables quick, yet thorough, vulnerability analysis. It can run scenario-simulations quickly. The basic assessment is based on process critical timeand security limit time. Additional analysis tools include: (i) priority list that enables quantitative evaluation of the effect of each variable on security, (ii) process security mapsthat are a visual aid for quick interpretation of results, (iii) “Ascent to Disaster” curves for zonal analysis of the problem, (iv) NCM matrices for identification of strictly coupled behavior in the system, and (iv) threat profiling for quantitative analysis of the security attack that leads to disaster. The current version of the software is restricted to CSTRs where exothermic reactions take place, but is otherwise fully customizable (i.e., reaction, operation conditions, etc., can be changed readily). • Process Security Assessment Software Highlights • Developed for educational use in process security and safety lectures • Allows the user to detect how secure their process is • Calculates how significant each system parameter is to plant security Example 2: Reactor Property Change • Detailed Methodology • -analysis technique • Mathematical framework for process security assessment theory • Examination of the gradient of time derivative equations of a plant dynamic model directly • Quick estimations for the minimum time that the process can go to disaster under a security threat • Definition of a “secure” process • If the time needed to detect the threat, and take the essential countermeasures to eliminate the threat, is less than the time it takes for the system to reach disaster conditions • Assumption of the worst conditions possible Process Security vs. Process Safety • Basic feature of most existing safety tools • Qualitative (for high-level decision making) • Probabilistic (for risk assessment) • Quantitative and deterministic analysis tools needed to complement existing tools • Core assumptions for process security • Possibility of technological sabotages • Control system malfunctions • Concurrent event occurrence • More conventional attacks • Bombing, takeover, etc. • Security threats • Possible but not probable • Focus • Eliminate vulnerabilities Ascent to Disaster Profile Software Help Boxes Brief descriptions or definitions of most software functions (right clicking the button) Software: Main Page Priority List Page • Security and Process Security • Security concerned • Conventional security • Brute-force attacks • Cyber security • Hacker attacks on information systems • Process security • Vulnerability of the process • Runaway reactions • Pressurized equipment Concluding Remarks The tool highly desirable for quantitative analysis of process security The tool ideal eventually for undergraduate education Future Work To broaden the range of security-sensitive operations To investigate design and operation aspects in much detail To be available on the web site: http://che.eng.wayne.edu/~yhuang • Software Features • Main functionalities • Calculation of the security assessment • Calculation of the system’s priority list • Security Assessment • Computation of the lower (critical time) and upper (limit time) bound times • A time range where the process goes from normal operation to disaster • Valuable for users to determine if the process is secure • Generation of Ascent to Disaster temperature profiles for the critical and limit times • Priority List • Calculation of the significance and percent significance values for each system parameter • Alert for the user to the parameters with the greatest significance to security • Parameters for closer watch • Fast Security Assessment Theory • For obtaining quick and reliable estimates to process security • Based on the minimum time to disaster concept (MTD) • MTD: The time for reaching disaster conditions in a worst-case scenario • Additional analysis tools • -maps • Priority list • Nonlinear contribution matrix • Threat profiles • Methodology: for reliable process security analysis & assessment • Low CPU-time & technical ease: attractive for large-scale problems • Con: Prediction of a range, not an exact value Most significant system parameters: jacket temp. (74.56%), liquid volume (26.28%) Software Flexibility Fully customizable for other reaction types Changeable of all system parameters Acknowledgement Example 1: Stream Data Adjustment National Science Foundation (CTS, 0211163) (CCLI, 0127307) (DGE,9987598) Sandia Nat’l Labs – Security Systems and Technology Center EPA Nat’l Risk Assessment Research Lab – Division of Sustainable Technology Wayne State University – Research Enhancement Program on IT