TO PROCESS SAFETY FOR

As a new engineer or an engineer new to process safety, it is very likely that you will be involved in some form of HIRA during your first few years in the process industry. In Table 2.1, the HIRA element corresponds to the Process Hazard Analysis (PHA). requirements of OSHA PSM and EPA RMP regulations. At Flixboroo, “the site engineer left at the beginning of the year and has not yet been replaced.

Figure 2.1. Picture of a nitroglycerine reactor in the 19th century.

Introduction

Purpose of this Handbook
Target Audience
Process Safety – What Is It?
Organization of the Book
References

The energy input from the deadhead pump increases the temperature and pressure of the fluid in the pump. Loss of contents may result in flammable or toxic releases, depending on the nature of the materials.

Process Safety Basics

Risk Based Process Safety

The Bhopal incident led to the establishment of the Center for Chemical Process Safety (CCPS) in 1985. Risk: To discuss a risk-based process safety program, the concept of risk must be understood.

Process Safety Culture

There are five elements to the pillar of Commit to Process Safety Process Safety Culture (Section 2.2). The organization strives to improve risk awareness and understanding as a means to continuous improvement in process safety performance.

Compliance with Standards

Organization for Economic Cooperation and Development – Guidelines on Chemical Accident Prevention, Preparedness, and1 Response, 2003 (Ref. 2.10) American National Standards Institute (Ref. 2.10). Malaysia – Department of Occupational Safety and Health (DOSH) Ministry of Human Resources Malaysia, Section 16 of Act 512 (Ref. 2.29).

Process Safety Competency

As a new engineer in a company, you will need to learn how your company ensures compliance with standards.

Workforce Involvement

This proactive engagement would illustrate at least two positives, the right people are involved in the review and the workforce, right down to operational staff, feel free to provide honest views without fear of negative consequences.

Stakeholder Outreach

Finally, the outreach element promotes the facility's involvement in the local community and facilitates the communication of information and facility activities that may impact the community. There are two elements in the pillar Understand risks and knowledge management of the risk process (Section 2.7) Risk identification and risk analysis (Section 2.8).

Process Knowledge Management

D]efficiencies in “process knowledge and documentation” and “capital project process safety reviews” contributed significantly to the incident.” Development and documentation of process knowledge starts early and continues throughout the process life cycle.

Hazard Identification and Risk Analysis

For example, early laboratory efforts to develop new materials, characterize those materials, and evaluate synthesis routes (including the potential for runaway reactions or other inherent hazards) typically become part of process knowledge. Process Hazard Analysis (PHA) is a HIRA that meets the specific regulatory requirements of the OSHA PSM standard in the US.

Table 2.4 Typical HAZOP review table format.

Operating Procedures

Asset Integrity and Reliability (Section 2.11) Supplier Management (Section 2.12) Training and Performance (Section 2.13) Management of Change (Section 2.14) Operational Readiness (Section 2.15) Operational Behavior (Section 2.16) Emergency Management (Section 2.17). Other workgroups, such as maintenance, should also be involved if the operating procedures could potentially affect them.

Safe Work Practices

Many countries may have specific regulations for safe work practices that industries must follow. Other safe work practices are often required by other regulations, regardless of the extent of chemical or other hazards present in the facility.

Figure 2.6. Collapsed tank at Motiva refinery, courtesy CSB.

Asset Integrity and Reliability

The involved line had 24 condition monitoring locations (CMLs), but there were no CMLs on the 52-inch section of pipeline. This element is covered by the mechanical integrity requirement of the OSHA PSM and EPA RMP regulations (see Table 2.1).

Figure 2.7. Rupture in 52-inch component of line, courtesy CSB.

Contractor Management

This section was more susceptible to sulphidation corrosion because it contained lower silicon levels than other sections of the pipeline (for piping components, lower silicon levels are known to be susceptible to high sulphidation corrosion rates). However, the use of contractors brings an external organization into the company's risk control activities.

Training And Performance Assurance

In this context, training broadly includes education in specific procedures related to operations, maintenance, work safety, and emergency planning and response, as well as the overall process and its risks. Training takes place both in the workplace and in the classroom and must be completed before an employee is allowed to work independently in a specific position.

Management of Change

Often, the final approval to implement the change comes from another designated individual, independent of the review team. The rule requires not only conducting the MOC review, but updating the Process Safety Information (PSI) and affected operating procedures and informing the workforce of the change.

Operational Readiness

Experience has shown that the frequency of incidents is higher during process transitions such as startup. For all startups (including those after minor, short-term shutdowns involving no changes), readiness reviews ensure that the process is safe to be released to operations by examining issues such as the equipment range, leak tightness, proper isolation from other systems. yet ready for startup, and cleanliness.

Conduct of Operations

A consistently high level of human performance is a critical aspect of any process safety program; Indeed, a less than adequate level of human performance will adversely affect all aspects of operations. As the complexity of operational activities increases, a commensurate increase in the formality of operations must also occur to ensure safe, reliable and consistent execution of critical tasks.

Emergency Management

Intended actions, such as evacuation versus shelter-in-place, should also be considered when incorporating scenarios into the emergency plan. Written contingency plans specify offensive response actions and form the basis for determining what facilities, equipment, personnel, training, communications, coordination, and other resources or activities are required.

Figure 2.8. Aerial view of the burning Monsanto plant after the 1947 Texas City Disaster, (http://texashistory.unt.edu/ark:/67531/metapth11883) University of North Texas Libraries, The Portal to Texas History, crediting Moore Memorial Public Library, T

Incident Investigation

There are four elements in the Commitment to Process Security Incident Investigation pillar (Section 2.18). Incident investigation is part of the OSHA PSM and EPA RMP regulations (see Table 2.1) and is covered by local and other country regulations.

Figure 2.9. CCPS and API Process Safety Metric Pyramid (Ref. 2.46).

Measurement and Metrics

Backlog indicators are generally not sensitive enough to be useful for continuous improvement of process safety management systems because incidents occur too infrequently. As a new engineer, you may be involved in collecting and even analyzing data for leading and lagging indicators.

Auditing

It complements other RBMP control and monitoring activities in the areas of data (paragraph 19), management review (paragraph 21) and inspection activities that are part of the elements of asset integrity and performance of operations (paragraphs 2.11 and 16) . Audits may be conducted by a team of qualified personnel selected from a variety of sources depending on the scope, needs and other aspects of the specific situation.

Figure 2.10. Photograph of failed end of heat exchanger, Ref. 2.33.

Management Review and Continuous Improvement

An audit or incident may eventually reveal incomplete or overdue training, but by then it may already be too late. The management review process provides for regular health checks of process safety management systems to identify and correct any current or emerging deficiencies before they can be revealed by an audit or incident.

Summary

Operators and perhaps maintenance personnel should be trained on the new procedure, process, etc. Changes to piping and equipment must be done in a safe manner (safe work practices).

According to the HSE, which investigates incidents in the UK, "the presence of corrosion was known but the full extent was not recognized because it was not inspected at the point of failure, where there were problems with inspection access." If they run dry (i.e. the inlet is blocked), the bearings can be damaged, causing high temperature.

Table 3.1 Selected incidents and Process Safety Management systems.

The Need for Process Safety

Process Safety Culture: BP Refinery Explosion, Texas City, 2005

Summary
Detailed Description
Causes
Key Lessons
References and Links to Investigation Reports

The investigation team concluded that Splitter was overworked and overheated because "the Shift Board Operator did not properly understand the process or the potential consequences of his actions or inactions on March 23rd.". Perhaps the most surprising of the CSB's findings are those regarding the process safety culture at BP and the Texas City plant.

Figure 3.2. Process flow diagram of the Raffinate Column and blowdown drum, source (CCPS, 2008)

Asset Integrity and Reliability: ARCO Channelview, Texas Explosion, 1990

Summary
Causes
Key Lessons

The preventive maintenance program for the oxygen analyzers and other safety-critical equipment was improved. The oxygen analyzer failed and the loss of nitrogen sweep was not noticed by the operators.

Process Safety Culture: NASA Space Shuttle Columbia Disaster, 2003

Summary
Causes
Key Lessons

The uncertainty over the long-term future of the program has led to reduced investment, with security upgrades delayed or postponed. An example of the poor safety culture at NASA is the refusal of requests by the Debris Assessment Team to image the wing while the shuttle was in orbit.

Figure 3.6. Columbia breaking up, courtesy NASA.

Process Knowledge Management: Concept Sciences Explosion, Hanover

Summary
Cause
Key Lessons
References and links to Investigation Reports

Also, CSI has not made any attempt to conduct tests to determine the extent of HA's danger. CSI did not implement any of the recommendations from the hazard assessment that they did.

Figure 3.8. Damage to Concept Sciences Hanover Facility, courtesy Tom Volk, The Morning Call

Hazard Identification and Risk Assessment: Esso Longford Gas Plant

Summary
Cause
Key Lessons

Methane rises to the top of the towers, with heavier hydrocarbons dissolving in the liquid hydrocarbon condensate, see Figure 3.10. All the plant's engineers were moved to the head office in Melbourne, Australia in 1992.

Figure 3.10. Simplified schematic of absorber, (CCPS, 2008).

Operating Procedures: Port Neal, IA, Ammonium Nitrate Explosion, 1994 77

Causes
Key Lessons

Calculations showed that the clearing of the nitric acid line would have lowered the pH at the time of the shutdown to about 0.8. As with the Esso Longford explosion (Section 3.5), no hazard assessment of the AN process had been carried out.

Figure 3.12 Neutralizer and rundown tank, source, (EPA, 1996).

Safe Work Practices: Piper Alpha, North Sea, UK, 1988

Summary
Causes
Key Lessons
Summary
Cause
Key Lessons

The investigation revealed that the immediate cause of this incident was the failure of the work permit system to control maintenance and inspection work on the platform. This pressure relief valve was located in the module above and out of sight of the pump.

Figure 3.14. Piper Alpha platform, source (CCPS, 2008).

Asset Integrity and Reliability: Explosion at Texaco Oil Refinery, Milford

Summary
Causes
Key Lessons

The wet gas compressor restarted successfully, but caused the pressure inside the debutanizer to rise again resulting in the PRV column reopening to ignite. Liquid levels also continued to rise in the wet gas compressor knock drums until it eventually shut down due to a high level in its interstage knock drum.

Figure 3.18. Ref. ( CCPS, 2008) Picture courtesy of Western Mail and Echo Ltd.

Conduct of Operations: Formosa Plastics VCM Explosion, Illiopolis, IL,

Summary
Causes
Key Lessons

When the bottom valve was opened, VCM poured out of the reactor and the building quickly filled with flammable liquid and vapor. In the case of the Formosa VCM explosion, the blaster's operators faced an error-prone design.

Figure 3.20. Smoke plumes from Formosa plant, source (CSB 2007).

Management of Change: Flixborough Explosion, UK, 1974

Summary
Cause
Key Lessons

This incident is significant in the history of process safety as a prime example of the importance of the MOC program. Although the presence of a mechanical engineer might not have changed the result if the MOC inspection had not been done in the first place, it is more likely that someone in the factory would have recognized the importance of the change.

Figure 3.23. Schematic of Flixborough piping replacement, source Report of the Court of Inquiry

Emergency Management: Sandoz Warehouse Fire, Switzerland, 1986

Summary
Key Lessons
References and links to investigation reports

Guidance on managing process security risks during organizational change (CCPS 2013) covers this topic in more detail. CCPS 2008, “Incidents That Define Process Safety”, American Institute of Chemical Engineers, Center for Chemical Process Safety, New York, NY, 2008.

Figure 3.27. Sandoz Warehouse firefighting efforts, source (CCPS, 2008)

Conduct of Operations: Exxon Valdez, Alaska, 1989

Summary
Causes
Key Lessons

Another operational problem was the Exxon Shipping Company's inability to supervise the captain. Factory management should spend some time in the field to observe and communicate with the factory conditions and staff behavior.

Figure 3.29. Exxon Valdez tanker leaking oil, courtesy of Exxon Valdez Oil Spill Trustee Council

Compliance with Standards: Mexico City, PEMEX LPG Terminal, 1984

Summary
Causes
Key Lessons

The orbs crashed to the ground as the legs buckled from the heat of the fire. Population density around a location is usually one of the inputs to these studies.

Figure 3.33 Layout of PEMEX LPG Terminal, source, CCPS, 2008).

Process Safety Culture: Methyl Isocyanate Release, Bhopal, India, 1984

Summary
Key Lessons

A pipe rack can be seen on the left and the partially underground storage tanks (three in total) for MIC are located in the. No adjustments have been made to the MIC storage tank protection strategy, such as increased monitoring or a reduction in the amount stored, as the layers have been removed.

Figure 3.36. Schematic of emergency relief effluent treatment system that included a scrubber and flare tower in series, source AIChE

Failure to Learn, BP Macondo Well Blowout, Gulf of Mexico, 2010

Summary
Key Lessons

Willey 2006, Willey et al., "The Accident at Bhopal: Observations 20 Years Later", Presentation to AIChE Spring National Meeting, April 2006). During this time, the well should be monitored for abnormalities, specifically a "kick" (an influx of hydrocarbons into the well that forces drilling mud back up the well).

Figure 3.38. Fire on Deepwater Horizon, source (CSB, 2010).

Summary

The Flixborough incident (Section 3.11) is often cited as a good example of the need for a good management of change programme. An outcome of the Exxon Valdez incident (Section 3.13) was Exxon's development of its Operational Integrity Management System (OIMS).

This can entail hazards depending on the properties of the fluid being moved. Loss of butadiene through the leaky valve resulted in significant changes in tray composition in the lower part of the column.

Table 4.1. Process safety activities for new engineers.

Process Safety for Engineering Disciplines

Introduction

Process Knowledge Management

With this information, they can determine the design and equipment used to control the process and the SIS. In smaller organizations, safety engineers may have a much larger role in process safety than in a larger facility, which may have separate responsibilities for job safety and process safety.

Compliance with Standards

During the project design phase, I&E and Control engineers are involved in the design of process control systems, safety control alarms and interlocks (SCAI), and safety instrumented systems (SIS). I&E and Control engineers are involved in the design of control systems, safety control alarms and interlocks (SCAI) and safety instrumented systems (SIS).

Hazard Identification and Risk Analysis, Management Of Change

The CCPS book Guidelines for the Management of Process Safety Risks during Organizational Change 2013 (Ref. 4.3) covers this topic. Just as a new engineer might engage in a MOOC review, he or she might also engage in a MOOC review for an organizational change.

Asset Integrity and Reliability

Reduction in staffing levels: After staffing reductions, the remaining ISOM operators are likely to be exhausted from working 12-hour shifts for 29 or more consecutive days. Reduction in staffing levels: Formosa eliminated an operator group leader position and passed responsibility to tour supervisors, who were not always as available as group leaders once were.

Safe Work Practices

I&E and control engineers will often be tasked with designing SCAI and safety instrumented (SIS) systems and ensuring that the required reliability and probability of failure are achieved as required. They may often be required to develop procedures for safety instrument system test protocols, instrument calibrations and tests, control loop response capabilities, etc.

Incident Investigation

Resources for Further Learning

All new technicians must sign up to receive the CCPS Process Safety Beacon (PSB) and Chemical Safety Board (CSB) press releases at the sites listed below. The CCPS Process Safety Beacon is a tool aimed at conveying process safety messages to plant operators and other production personnel.

Summary

The program can predict potentially harmful interactions between two chemicals and display them in a compatibility chart. It provides physical and hazardous properties of many chemicals and allows the user to build a pool of chemicals and determine the hazards of uncontrolled mixing.

Failures in heat transfer equipment can lead to loss of temperature control, contamination of one of the fluids, or loss of inhibition. Upon their return, one of the two owners went to the control room to help.

Process Safety in Design

Process Safety Design Strategies

Minimize – use small amounts of hazardous materials, reduce the size of equipment that operates under hazardous conditions such as high temperature or pressure. Resources for ISD include Inherently Safer Chemical Processes – A Life Cycle Approach (Ref. 5.1) and Process Plants – A Handbook for Inherently Safer Design (Ref. 5.2).

General Unit Operations and Their Failure Modes

Pumps, Compressors, Fans
Heat Exchange Equipment
Mass Transfer; Distillation, Leaching and Extraction, Absorption
Mechanical Separation / Solid-Fluid Separation
Reactors and Reactive Hazards
Fired Equipment
Storage

The loss of liquid level at the bottom of the column exposed the reboiler tubes, allowing the tube wall temperature to approach the temperature. When other parts of the plant were shut down, the temperature of the steam in the reactor rose to 300 C.

Figure 5.1. Damage from fire caused by mechanical seal failure.

Petroleum Processing

General Process Safety Hazards in a Refinery
Crude Handling and Separation
Light Hydrocarbon Handling and Separation
Hydrotreating
Catalytic Cracking
Reforming
Alkylation
Coking

Transient Operating States

Overview
Example Process Safety Incidents
Design Considerations

Course Material

Introduction

Inherently Safer Design

Process Safety Management and Conservation of Life

Process Safety Overview and Safety in the Chemical Process Industries

Process Hazards

Chemical Reactivity Hazards
Fires and Explosions
Other Hazards

Hazard Identification and Risk Analysis

Emergency Relief Systems

Case Histories

Runaway Reactions
Other Case Histories

Other Modules

Summary

Process Safety in the Workplace

What to Expect

Formal Training
Interface with Operators, Craftsmen

New Skills

Non-Technical
Technical

Safety Culture

Conduct of Operations

Operational Discipline
Engineering Discipline
Management Discipline
Other Conduct of Operations Topics for the New Engineer

Summary

Chemical Reaction Hazard Identification

Reaction Process Design Considerations

Resources and Publications

Screening Table and Flowchart