 |
White Papers
SIS Design Basis Revalidation
Since the time of the original release of ANSI/ISA 84.00.01, a lot of process industry users have made great strides at updating and improving their safety instrumented system (SIS) implementation practices to be in conformance with the standards. Even so, some control system practitioners and loss prevention specialists are beginning to question the validity of both the design basis documentation that has been developed and the ability of the installed equipment and management systems to meet those targets because of process changes and erroneous initial assumptions. Because procedures are not always followed and mistakes occur, the regulators and the standards writers have included provisions in their respective guidance documents to periodically go back and review prior hazard analysis studies and design basis documents to ensure that they are still valid.
Download
Hydrocracker Reaction Safeguarding
Emergency depressuring of Hydrocracking process units in refineries received a large amount of attention after some catastrophic accidents. Many refiners decided that automatic depressuring of the unit when excess temperature was detected should be a safety instrumented function and replace the traditional manual depressuring. When attempting to implement the ISA 84.01 safety lifecycle, refiners found that applying this safety instrumented function is quite difficult in terms of risk analysis to determine the required safety integrity level (SIL). This white paper discusses the selection of a SIL for the depressuring function. The Hydrocracking process is of great interest in terms of SIL selection because of the advanced methods that are required to provide reasonable results.
Download
Safeguarding Oxidation Reactions
Reactions which oxidize hydrocarbon feed stocks to create chemical intermediates are extremely common in the process industries. These processes involve a number of hazards that can be effectively controlled by the use of safety instrumented systems. This white paper discusses typical oxidation processes, describes hazards that they pose, presents a history of accidents from oxidation reactions, and provides an overview of some typical safety instrumented functions that are employed on oxidation reactions with typical.
Download
Functional Safety Assessment and Certification to IEC 61511
Certification by independent third parties is a valuable tool that has been utilized by industrial companies to ensure that the products (and more recently services) that they receive are performed in compliance with some national or international standards of relevance. Standards and certifications that are related to functional safety of safety instrumented systems and the equipment that is employed in safety instrumented system service have a high level of importance due to the very significant consequences that could occur if these equipment or these services were performed in a non-compliant manner.
Download
Artificial Intelligence Advancements Applied in Off-The-Shelf Controllers
Since the earliest process units were built, CPI engineers have employed Artificial Intelligence to prevent losses. The expanding use of computer-based systems for process control has allowed the amount of intelligence applied in these expert systems to drastically increase. Standard methods for performing Expert System tasks are being formalized by numerous researchers in industry and academia. Work products from these groups include designs for the representation of knowledge of process hazards in a structured, hierarchical, and modular manner.
Download
Process Control Safety Standards as Institutional Memory
Design standards and guidance documents that are the basis for BPCS design should include an “institutional memory” of the incidents and accidents that have occurred in the plant and industry. All accidents should be analyzed to determine their root cause. The root causes of accidents should also be reviewed to determine how to prevent the accidents from occurring in the future. When the root cause or contributor to an accident is the result of a BPCS failure or design flaw, process control design documents need to be altered so that similar accidents can be avoided in the future.
Download
Justifying the Use of High Integrity Pressure Protection Systems (HIPPS)
As chemical plants and petroleum refineries plan for future expansion, the capability of existing pressure relief systems to safely dispose of higher capacities is often a significant constraint. Current codes and standards now allow for the use of High Integrity Pressure Protection Systems (HIPPS) in lieu of increasing the capacity of emergency relief systems. There is a significant body of knowledge on how to design a HIPPS system once the requirement for one has been established. However, there is gap in knowledge of what situations allow for HIPPS and what practical steps can be taken to determine when a HIPPS is justified. This paper describes the analytical techniques that can be used by engineers to justify a design using instrumented protection in lieu of upgrading the relief system. A review of applicable requirements from codes and standards is included along with risk-based methods to ensure a HIPPS design is as safe as -- or safer than -- conventional relief design.
Download
Oxidation Reaction Safeguarding with SIS
A variety of useful chemical compounds are economically produced using catalyzed oxidation reactions. These products include many common organic acids and anhydrides, industrial alcohols, and organic peroxides. Safely conducting catalyzed oxidation reactions on an industrial scale is a core competency of many chemical companies. However, there is a history of numerous incidents involving fire and explosion in oxidation reactors, and these accidents are compelling reminders of the hazards of oxidation reactions.
Download
Advancing Quantitative Fire and Gas Detection and Suppression Systems Analysis
Fire and Gas detection and suppression systems have long formed an important part of the Loss Prevention toolkit for plants that process highly hazardous chemicals, both flammable and toxic. While every effort is made to prevent loss of containment of flammable and toxic chemicals, history has shown us that not only do these events occur, but those that are not prepared for them suffer major businesswrecking losses from which they may never recover.
Download
|
|
