0. Environment, Safety, and Economic Evaluation
Production of Synthesis Gas By Partial Oxidation of Natural Gas
Environment, Safety, and Economic Evaluation
Prof. Mohamed A. Fahim
Eng. Yusuf Ismail Ali
Group II :
Bibi AL-Mutawa’a
Mariam AL-Shamma’a
Dalal AL-Othman

1. Plant Safety
By: Bibi Al-Mutawa’a
Bibi Yousef Al-Motawa

2. What is HAZOP?
Systematic technique to identify potential hazard and Operating problems
A formal systematic rigorous examination to the process and engineering facets of a production facility
A qualitative technique based on “guide-words” to help provoke thoughts about the way deviations from the intended operating conditions can lead to hazardous situations or operability problems
hazop is basically for safety
- Hazards are the main concern
- Operability problems degrade plant performance (product quality, production rate, profit)
Considerable engineering insight is required - engineers working independently could develop different results

3. Objective of HAZOP
For identifying cause and the consequences of operations of equipment and associated operator interfaces in the context of the complete system.

4. How and Why HAZOP is Used
HAZOP identifies potential hazards , failures and operability problems.
Its use is recommended as a principal method by professional institutions and legislators on the basis of proven capabilities for years.
It is most effective as a team effort consists of plant and prices designers, operating personnel, control and instrumentation engineer.
It encourages creativity in design concept evaluation.
Necessary changes to a system for eliminating or reducing the probability of operating deviations are suggested by the analytical procedure.
HAZOP provides a necessary management tool and bonus in so far that it demonstrates to insurers and inspectors evidence of comprehensive thoroughness.

5. How and Why HAZOP is Used
HAZOP reports are an integral part of plant and safety records and are also applicable to design changes and plant modifications, thereby containing accountability for equipment and its associated human interface throughout the operating lifetime.
HAZOP technique is now used by most major companies handling and processing hazardous material, especially those where engineering practice involves elevated operating parameters :
- oil and gas production
- flammable and toxic chemicals
- pharmaceuticals etc
Progressive legislation in encouraging smaller and specialty manufacturing sites to adopt the method also as standard practice.

6. Features of HAZOP Study
Subsystems of interest line and valve,
Equipment, Vessels
Modes of operation Normal operation
Start -up mode
Shutdown mode
Maintenance /construction / inspection mode
Trigger events Human failure
Equipment /instrument/component failure
Supply failure
Emergency environment event
Other causes of abnormal operation, including instrument disturbance

7. Features of HAZOP Study
Effects within plant Changes in chemical conditions
Changes in inventory
Change in chemical physical conditions
Hazardous conditions Release of material
Changes in material hazard characteristics
Operating limit reached
Energy source exposed etc.
Corrective actions Change of process design
Change of operating limits
Change of system reliability
Improvement of material containment
Change control system
Add/remove materials

8. Features of HAZOP Study
How would hazardous During normal operation conditions detected ? Upon human failure Upon component failure In other circumstances Contingency actions Improve isolation Improve protection

9. Documents Needed for HAZOP Study
Process Flow Sheet ( PFS or PFD )
Description of the Process
Process Data Sheets
Instrument Data Sheets
Hazardous Area Classification

10. Before Detailed HAZOP
The development will follow a normal standard procedure and include the following considerations :
Basic process control system - this is a closed loop control to maintain process within an acceptable operating region.
Alarm system - this is to bring unusual situation to attention of a person monitoring the process in the plant
Safety interlock system - this is to stop operation or part of the process during emergencies.
Relief system - this is to divert material safely during emergencies.

11. HAZOP Study Procedure GUIDE WORDS
POSSIBLE CAUSES DEVIATION ( FROM DESIGN AND/OR
OPERATING INTENT )
CONSEQUENCES
ACTION(S) REQUIRED OR RECOMMENDEED

12. Guide Words NONE No forward flow when there should be
MORE More of any parameter than there should be, more flow, more pressure, more temperature.
LESS As above, but "less of" in each instance
PART System composition difference from what it should be.
MORE THAN More "components" present than there should be for example, extra phase, impurities.
OTHER What needs to happen other than normal operation, e.g. start up, shutdown, maintenance

13. Guide Words
NONE e.g., NO FLOW caused by blockage; pump failure; valve closed or jammed : leak: valve open ;suction vessel empty; delivery side over - pressurized : vapor lock ; control failure
REVERSE e.g., REVERSE FLOW caused by pump failure : NRV failure or wrongly inserted ; wrong routing; delivery over pressured; back- siphoning ; pump reversed
MORE OF e.g., MORE FLOW caused by reduced delivery head ; surging ; suction pressurised ; controller failure ; valve stuck open leak ; incorrect instrument reading.

14. Guide Words
MORE OF MORE TEMPERATURE, pressure caused by external fires; blockage ; shot spots; loss of control ; foaming; gas release; reaction;explosion; valve closed; loss of level in heater; sun.
LESS OF e.g., LESS FLOW caused by pump failure; leak; scale in delivery; partial blockage ; sediments ; poor suction head; process turndown.
LESS e.g., low temperature, pressure caused by Heat loss; vaporization ; ambient conditions; rain ; imbalance of input and output ; sealing ; blocked vent .
PART OF Change in composition high or low concentration of mixture; additional reactions in reactor or other location ; feed change. 

15. Guide Words
MORE THAN Impurities or extra phase Ingress of contaminants such as air, water, lube oils; corrosion products; presence of other process materials due to internal leakage ; failure of isolation ; start-up features.
OTHER Activities other than normal operation start-up and shutdown of plant ; testing and inspection ; sampling ; maintenance; activating catalyst; removing blockage or scale ; corrosion; process emergency ; safety procedures activated ; failure of power, fuel, steam , air, water or inert gas; emissions and lack of compatibility with other emission and effluents.

16. HAZOP Study HAZOP study are applied during : Normal operation
Foreseeable changes in operation, e.g. upgrading, reduced output, plant start-up and shut-down
Suitability of plant materials, equipment and instrumentation
Provision for failure of plant services, e. g . steam, electricity, cooling water
Provision for maintenance.

17. Case Study – Shell & Tube Heat Exchanger
Using relevant guide works, perform HAZOP study on shell & tube heat exchanger
Process
fluid
Cooling water

18. HAZOP on Heat Exchanger
Guide Word
Deviation
Causes
Consequences
Action
Less
Less flow of cooling water
Pipe blockage
Pipe leakage
Heat tubes burst
Temperature of process fluid remains constant
Process fluid temperature too low
Explosion
High Temperature Alarm
Installation of flow meter
Flow alarm or shutdown
Less pressure in tubes
Burst pipe
Alarm low pressure
More
More cooling flow
Failure of cooling water valve
Temperature of process fluid decrease (TOO LOW)
Low Temperature Alarm
Flow alarm
More pressure on tube side
Failure of process fluid valve
Tube blockage
Bursting of tube
Tube failure
Install high pressure alarm
Pressure relief system on tubes

19. HAZOP on Heat Exchanger
Guide Word
Deviation
Causes
Consequences
Action
NONE
No cooling water flow
Failure of inlet cooling water valve to open
Process fluid temperature does not decreased
Install Temperature indicator before and after the process fluid line
CONTAMINATION
Process fluid contamination
Contamination in cooling water
Outlet temperature too low
Proper maintenance and operator alert
Other
Maintenance
Equipment failure , pipe leak
Process stops
Ensure all pipes and fittings are constructed of the right material and are stress relieved

20. HAZOP on Heat Exchanger
Part of
Low fuel gas
Empty storage
Cooler freezing
Install low flow alarm in fuel gas
Low cooling water
Decrease absorption
Increase pollution
Increase impurities in syngas product
Install low level alarm on cooling water
More than
Organic acid present
Corrosion of tube
Less cooling and crack of tube
Hardness of cooling water
Proper maintenance to check suitability of material of construction

21. HAZOP TEAM
Team Leader / Chairman Extensive experience of process design and preferably commissioning and operations in a processing environment. Good motivation and meeting leadership skills are required. Independent of the design team.
Secretary / Scribe Familiar with the technology and terminology of the study. Competent to record the proceedings with a minimum of direction from the chairman. Keyboard skills necessary for word processor and software recording packages.
Independent Process Engineer Senior chemical/process engineer with at least five years experience in the relevant process technology. Independent of the design team. Role is to question process design assumptions, ensure design is to appropriate standards, advise team about process technology and assess likely consequences of process deviations.

22. Operations Representative Considerable operating experience in the type of process under study. Role is to describe operating practices, identify potential for deviation from operating intent and provide information about plant stability, ergonomics, means of preparing plant for maintenance, etc.
Design Process Engineer Familiar with the design intent. Role is to describe overall scheme and process safety systems, provide design intention and process conditions for each plant section, and explain process consequences of deviations.
Instrument / Control Engineer Provide information about overall control and safeguarding philosophy, interlocks and alarms, plant shutdown system, safety features, e.g. F&G detection.
Plant Engineer Provide information about compatibility with existing plant, site utilities, plant layout, maintainability and reliability requirements
Safety Engineer Provide information about plant safety philosophy, safety equipment, emergency response procedures, previous incidents and matters concerning public safety.

23. CONCLUSION Benefit of hazop
During the design of a new plant, design personnel are under pressure to keep the project on schedule.  This pressure frequently results in errors and oversights.  HAZOP study is an opportunity to correct these before such changes become too expensive, or impossible to accomplish.
Besides safety hazards, the HAZOP technique is very effective for identifying plant operability problems, threats to the environment, product quality, plant throughput and for highlighting critical maintenance requirements.

24. CONCLUSION Limitation of Hazop
HAZOP is a powerful technique but the extent to which it can uncover all foreseeable hazards is limited by the knowledge, experience and deductive skills of the HAZOP team. For these reasons, it is difficult to assess the ‘quality' of a given HAZOP in any objective or auditable way. Audits can be carried out to establish that the process has been followed, but they cannot verify the competence of the team.

25. Thank you