safety in chemical process industries

8/2/2019 Safety in Chemical Process Industries

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Safety In Chemical Process

Industries



Why does it matter? Safe working protects:

You

Other lab workers Cleaners

Visitors

Your work



Control Measures (in order of preference)

1. Use a less risky

substance2. Use a safer form of that

substance (eg solutioninstead of powder)




3. Totally enclose theprocess (eg a glove-box)

4. Partially enclose theprocess (eg with afume cupboard)

5. Ensure good general ventilation




6. Safe systems of work

7. Reduce exposure

times, increasedistance, reduce volumes

8. Personal protective

equipment (as a last resortfor primary protection)



What are the general hazards in a

laboratory? Fire Breakage of glassware Sharps

Spillages Pressure equipment & gas

cylinders Extremes of heat & cold Chemical hazards Biological hazards Radiation

And many more!



First Aid All laboratory workers should

undergo simple first aidtraining For ALL chemical splashes, wash

with plenty of water for 10minutes

Control bleeding with directpressure, avoiding any foreignbodies such as glass

Report all accidents to yoursupervisor or departmentalsafety officer



Abhinav Jain

Conc. HCL



Safety Programs System

Attitude

Fundamentals Experience

Time

You



Five Major Disasters: Bhopal Gas Tragedy

Flixborough accident

The Seveso disaster The Texas Tragedy

IOC Depot Fire(Jaipur)



Bhopal Gas Tragedy

Amongst the worst Industrial Disasters of its time.Occurrence: 3rd December 1984.

Place of occurrence: Bhopal, Madhya Pradesh, India.

Company: Union Carbide Corporation.

Chemical: Methyl Isocyanate (27 tons)



Toxic Materials in Soil and Water



25 Years after the Bhopal Gas

Disaster Changes Made in India

Changes made in USA

http://indiaprocesssafety.blogspot.com/2010/01/25-years-after-bhopal-gas-disaster.html






Flixborough Explosion



The Flixborough disaster was an explosion at a chemical plant

close to the village of Flixborough England on 1 st June 1974.

28 workers were killed and 36 injured on the site.53 people were injured off-site.1821 houses were damaged.

LessonsThe accident occurred due to: Poor Process DesignLack of Understanding of Mechanical Loading of Process Equipment

18



Simplified flow diagram of cyclohexane oxidation plant

after March 1974 (Whittingham, 2005)

(Whitti h )



(Whittingham, 2005)



The Seveso accidentOccurrence: July 10,1976Place of Occurrence: Seveso,Milan,Italy Company: Icmesa Chemical Company Chemical:TCDD (2,3,7,8-tetrachlorodibenzoparadioxin)



Suffering

10 square miles were contaminated

250 cases of chloracne were reported

Over600 people were evacuated 2000 people were given blood tests



Causes

Trichlorophenol reactor went out of control

Heavy Rain



Preventive Measures

Proper containment systems

Fundamental engineering safety principles



The Texas Tragedy

Occurrence: October 23,1989Place of Occurrence: Pasadena,Texas,USHigh Density Polythene Plant



Casualty 23 Deaths

314 injuries

Capital losses of over $715 million



Causes Product taken off valve was

removed

DEMCO was open

Lockout device wasremoved

No permanentcombustible gas detection

and alarm system waslocated in the region of thereactors. Polyethylene plant settling leg and produc

takeoff system



Preventive Measures A double-block-and-bleed valving arrangement should

have been used

Provision was made for the development,implementation, and enforcement of effective permitsystems



IOC Depo Fire (Jaipur)

Occurred:Oct 29th

PlaceofOccurrence:Sitapura

Copmany: IOCL



Casualty 12 people died

Over 200 people get injured

Half million people were evacuted



Causes Leakage in Valve

Negligence



RISK ANALYSIS



What Risk Analysis Can Do?Helps In

Forecasting any unwanted situation

Estimating damage potential of suchsituation

Decision making to control such situation

Evaluating effectiveness of controlmeasures



Risk Analysis Definition of Risk Analysis : “Risk analysis is the process of gathering

data and synthesizing information to develop an understanding of therisk of a particular enterprise.”

Definition of QRA : “QRA is the art and science of developing andunderstanding numerical estimates of the risk (i.e., combinations of the expected frequency and consequences of potential accidents)associated with a facility or operation.”

Risk analysis usually involves several of the five risk managementactivities shown in next slide.



Elements of Risk Management



Process of Risk Analysis



Why perform QRA ? There may be either of the two reasons to perform QRA:

First, you choose to use QRA because you believe you will gain abetter understanding of risk that will aid decision making.

A second possibility is that, in some cases, QRA may be required by law, so you choose to do one.

If you are performing QRA because you want to, then there may meseveral reasons:

Underlying Motivation (It is simply a perception that a problemexists)

Concerns (You concerns the safety & economic issue) Need (need for greater risk understanding)

Information Requirement (You want to get the information by the means of QRA)



Information Available From QRA The results of the QRA can be formulated and used on two bases:

An absolute basis

A relative basis

QRA

An absolute basis:•To determine whether the level of safety at a facility meets risktolerance criteria•If not, then change the faculty until

it meets the tolerance criteria

A relative basis:•Shows difference between the levelsof safety of one or more cases of interest•It can be used to determine the

most efficient way to improve safety



Classical Limitations of QRA

Completeness

Accuracy/Uncertainty Reproducibility

Inscrutability

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