Improving Process Safety

Future technology developments in paraffin alkylation will be greatly influenced by environmental considerations. The demand for alkylate product will continue to increase because alkylate is one of the most desirable components in modern low emission gasoline formulations. Increased attention will be focused on improving process safety, reducing waste disposal requirements, and limiting the environmental consequences of any process emissions. 

The book does not focus on occupational safety and health issues, although improved process safety can benefit these areas. Detailed engineering designs are outside the scope of this work. This book intends to identify issues and concerns in batch reaction systems and provide potential solutions to address these concerns. This should be of value to process design engineers, operators, maintenance personnel, as well as members of process hazards analysis teams. While this book offers potential solutions to specific issues/concerns, ultimately the user needs to make the case for the solutions that provide a balance between risk... 

There may be well-run facilities in which the operators are doing their best to be careful with facilities or systems that could be redesigned to be inherently safer. These facilities will be inherently safer if designed for operability. Note that inherently safer human factors features can reduce risk of injury to employees (improved personnel safety) and can reduce risk to the process from the worker (improved process safety). 

This book has been written to show how the science of human factors can be applied at the plant level to significantly improve human performance and reduce human error, thus improving process safety. 

The likelihood of success of any endeavor is largely dependent on the commitment to that success. This is especially true with improving process safety and reducing human errors. That commitment must start at the very top and flow strongly through all levels of the organization. 

Over 50 corporations from all segments of the chemical process industries (CPI) support the Center. They help fund the Center they select CCPS projects relevant to improved process safety and they furnish the professionals who give the Center s works technical direction and substance. 

As the chemical process industries have developed more sophisticated ways to improve process safety, we have seen the introduction of safety management systems to augment process safety engineering activities. ... 

As noted above, batch and semi-batch-based operations result in periodic high loads and subsequent over-design and increased capital cost. By destroying the hypochlorite in situ, within the scrubber recycle loop, the end of cycle concentration can be reduced and the load on the end-of-pipe hypochlorite destruction system lowered allowing an overall cost reduction. The reduced free chlorine concentration also leads to improved process safety, although increased heat removal is required. 

Although the main cost advantage arises in batch systems the same principle can be applied to continuously operated scrubbers. This allows operation at a lower standing hypochlorite concentration in the scrubber and thus leads to improved process safety... 

The process and equipment documentation, as well as the operating and upset procedures, should create an archival history of the operation. In addition, while it is important to know the status of the operation, it is also important to be able to look back and learn from the operation s history to improve process safety continuously. 

ACC has published a resource guide to aid member companies in implementing the Responsible Care Process Safety Code (ACC, 1989). Although the guide provides suggestions on how to continually improve process safety, it does not prescribe how to comply with the code. It does not list specific requirements for reactive hazard management, but does require management systems to be developed-several of which could apply to reactive hazards as determined by each member company. 

Secondary prevention and mitigation, by themselves, are unable to eliminate the risk of serious or catastrophic chemical accidents, although improved process safety management can reduce their probability and severity. Most chemical production involves transformation processes, which are inherently complex and tightly coupled. Normal accidents are an unavoidable risk of systems with these characteristics [11]. However, the risk of serious, or catastrophic, consequences need not be. Specific industries use many different processes. In many cases, alternative chemical processes exist which completely or almost completely eliminate the use of highly toxic, volatile, or flammable chemicals [12]. 

These different temperature and feed control strategies and their impact on reactor safety, together with general rules for assessing and improving process safety, are presented below. The choice of the reactor temperature and feed rate is also of primary importance for safety and this point will be discussed in the last section of this chapter. 

Kletz also considers that the technical design of the process has a positive impact on its safety. Here too he quotes several principles to improve process safety by technical design ... 

The CCPS s process safety management system approach that uses risk-based strategies and implementation tactics that are commensurate with the risk-based need for process safety activities, availability of resources, and existing process safety culture to design, correct, and improve process safety management activities. 

To provide guidance to companies at corporate and site levels on how to use performance metrics effectively to improve process safety performance ... 

Process Safety Specialists—those at the corporate and facility levels responsible for the process safety system including tailoring the system to specific facilities and using metrics to monitor and maintain or improve process safety performance. 

Corporate Leaders—those providing the leadership commitment, setting the expectations, for a process safety performance and the supporting metrics system including the resources necessary to develop and implement such a program throughout the corporation to improve process safety. 

Other audiences and stakeholders interested in improving process safety are also likely to find this book useful and informative and may include ... 

Chapter 9—Future Trends in the Development and Use of Process Safety Metrics for improving process safety performance and broader societal interests... 

Justifying financial support for improving process safety systems often requires priority over competing business systems needs, and experienced opinion alone is not always sufficient justification. Company leaders are usually more influenced by data-supported justifications. 

Any organization that wishes to improve and sustain process safety performance must clearly establish its performance goals and objectives. Efforts to sustain and improve process safety performance will require a means to measure and evaluate that performance. Collecting performance information enables an organization to achieve their desired goals and objectives by helping to ... 

As an organization begins an effort to improve process safety performance, it should establish specific goals and objectives that reflect performance outcomes and the desired future state of process safety. Senior leadership needs to lead the development of goals and objectives to signal full support and demonstrate active engagement. 

An organization will follow various strategies to strengthen its process safety system. While developing the plans to improve process safety, the organization may identify many improvement opportunities. It is often impractical to address all identified opportunities simultaneously since the sheer number of potential failures... 

---