Chemical Processing Unit shutdown Safety

Overview of Safety during Continuous Chemical Processing Unit shutdown

Process safety is a significant, mandatory investment in today’s competitive global market. It takes care of plant assets and ensures the protection of workforce safety and maintains a safe work environment. Most chemical manufacturing units are operational round the clock and round the year, to prevent any major breakdown and maintain the safety and health of equipment and their components, a planned or scheduled shutdown of the entire unit is essential which is called turnaround also. Shutdowns are scheduled as per market strategy and production targets depending upon the need of the unit at pre-defined intervals.

Sometimes emergency stoppages or unwanted situations in the processing activities force to stop all operations to address remedial actions/ maintenance concerns such as cleaning, inspection, and repair. Implementation of preventive measures, periodic safety checks, periodic equipment inspections, regular condition monitoring as well as regular upkeep and scheduled maintenance help to avoid emergency breakdown/shutdown.

The interruption during normal operation of the unit is a costly exercise, but at the same time, the shutdown is very much essential in managing a safe chemical plant operation. Shutdowns need to be addressed from the chemical hazards perspective because hazardous process chemicals are still present at the installation in storage tanks, warehouses, silos, and pipelines even when the production process is not running and most of the equipment has been emptied and flushed/cleaned.

Occasionally emergency situations also force chemical plant shutdowns. For continuous operation of any chemical manufacturing plant, if one or more key units break or any leakage takes place or malfunctioning takes place, an emergency shutdown may be declared to protect the health and safety of employees. Emergency shutdowns are often imperative to prevent situations from worsening the plant situation.

Routine and scheduled turnarounds are planned for total or partial plant units. These unit stoppages are critical for allowing contractors’ manpower and employees to perform crucial activities and plant upkeep to maintain facilities running safely and effectively. There are certain tasks that are necessary, and they can be attended to only during turnarounds periods, they are to be accomplished during non-operation periods.

Shutdowns can be very costly in terms of the contractual manpower and expertise required to complete the work as well as to reduce production losses during the closures of plants. Hence it is very much important for top management to avoid emergency shutdowns and plan turnarounds so that extra losses can be reduced, and shutdown activities run as smoothly as possible to reduce any extraneous downtime of operating units. It is the duty of Plant managers to consider these key safety and regulatory components while planning for turnarounds:

For a routine shutdown, managers plan to maximize the event for efficiency, repairs, and safe execution. Shutdowns are planned when the unit is not operational which allows necessary modification/alternation and major repairs/replacement. Safety is always a top priority in any plant shutdown.

Major safety concerns during the shutdown are toxic chemicals and potential contamination hazards. During a shutdown, it’s likely that many additional shutdown specialist contractors’ manpower/technicians will be working. It’s imperative to educate and train them on plant hazards and the safety of shutdown activities to ensure the turnaround runs safely and smoothly. Shutdowns are expensive and can greatly affect plant operation bottom lines. All preventive measures are taken to keep the plant safe and viable in the future during the shutdown so that no emergency shutdowns happened in the future.

For any shutdown, a risk assessment, well-documented procedure, proper communication well-trained workforce, and effective safety management and technology are essential.

Major challenges during the shutdown activities include:

• Hazardous gases/toxic gases that are constantly present.
• Possible leakage of hazardous gases/liquids
• Confined space entries for repair or maintenance work
• Heavy lifts and shift of equipment/ piping etc.
• Poor housekeeping
• Expertise in modification/alternation
• Skills and Knowledge of the workforce

?General Safety rules to be followed during Shutdown for Life Protection.

• No drugs or alcohol, No smoking,
• Non-use of mobile phones in a hazardous area.
• No Violation of Work Permit Conditions
• No line break without authorization
• No Confined Space entry without authorization.
• Classification of Violations and Level of actions
• ?Consequence Matrix

Area of concern during shutdown Activities

• Hazard Communication
• Confined Spaces
• Hot work like Gas cutting, Grinding, Welding, etc.
• Line Breaking
• Fall Protection
• Ladders, Scaffolding
• Work at a height
• Machine Guarding
• Barricading
• Oil Spills
• Radiation
• Specific Personal Protective Equipment
• Temperature difference, Environment issues.
• Housekeeping
• Powered Industrial Trucks
• Safe operation of vehicles
• Powder-actuated tools.
• Electrical hazards
• Excavation Activities
• Safety planning
• Hazard identification:
• Checklist

?Pre-shutdown/Shutdown activities:

• Preparation: It is observed that 4 months in advance shutdown activities are planned at a micro level to ensure a safe plant shutdown.
• Regular plant inspections: Carry out regular inspections, review, and update documented shutdown procedures.
• Educate and Train the workforce: Provide job-specific structured training to overcome high levels of risk associated with the work, and refresher training to be given every year.?
• Disconnect/isolate all equipment: Provide positive isolation to all equipment and system as documented.
• Storage of hazardous Materials: Store all hazardous and dangerous materials safely and away from the work area.
• Monitor exposure risk: Beware of a risk of exposure to toxic chemicals, acidic chemicals, flammable gases, toxic fumes, airborne fibbers, etc. A trained safety specialist to test for exposure risk and ensure the correct protection.
• Keep rotating equipment turned off: Ensure positive isolation of power to equipment, to make sure the system is turned off.
• Keep enough resources: Deputing an adequate workforce to execute the shutdown to ensure not to compromise on safety.
• Keep communicating: Develop a system to quickly communicate if there is a danger. Have safety slogans, talk messages, and/or banners with a simple message such as “do not operate.” ?This is to save time and avoid injury.
• Use qualified personnel: Ensure the shutdown workforce is well qualified and trained in their respective area of concern to maintain safety.
• Documentation and Procedures: Always obtain approval from inspectors and have a documented process for maintaining each part of equipment/machine. The procedure includes information like who will do the work, what is to be controlled etc.
• Use appropriate PPEs and personal safety monitoring systems: Ensure worker safety by using appropriate hazard detection and protection equipment.

?To maintain the safety & health of employees and operational units a comprehensive safety shutdown management system is planned, it creates interrelated layers of protection to detect, prevent, and manage potential safety and security risks during the shutdown. This calls for effective and safe plant machinery, and activities to maintain operations safe which is visible, efficient, and productive.

Plant Shutdowns are some of the most challenging undertakings in the chemical industry. The highest priority is to ensure the health and safety of the workforce.?At the same time important aspect is to minimize cost and downtime. With well-trained and well-equipped personnel, it is possible to manage any plant shutdown and maintenance smoothly and successfully.