HAZOP Study for Mangalore Refinery and Petrochemicals

Manglore Refinery and Petrochemical Ltd (MRPL), a schedule “A” CPSE and a Subsidiary of ONGC is a state of the art grass root large scale refinery complex located in  North of Manglore city, in the State of Karnataka. The Refinery has a versatile design with high flexibility to process crudes of various API and with high degree of automation. MRPL has a design capacity to process 15 million MMTPA.

The major processing units in the refinery are Crude and Vaccum Distillation Units, Visbreaker Units, Hydrocrakers Units, Hydrogen generation Units, continuous Catalytic Regeneration Units, Petrochemical fluidized catalytic cracking Unit, Isomerization Unit, Mixedxylene Unit, Coker heavy gas oil hydrotreating Unit, ATF/Kero & LPG treatment Units, Polypropylene Unit, Diesel Hydrotreating Unit, Delayed Coker Unit and Sulphur recovery Units. Power and stream required for Refinery operations is supplied by captive Power Plants. Dedicated Waste Water Treatment Plants are provied for treating the effluent generated in the refinery to the standards prescribed by Central/State Pollution Control Board.

MRPL also owns and operates cross country pipelines to receive crude oil and transport finished products to and from Jetty of new Manglore port respectively. Further, MRPL owns and operates single point Mooring Facilities of the cost of Manglore to receive large to very large Crude Oil Carriers.

The Crude Unit is the primary processing unit in an Oil Refinery wherein Crude Oil is separated into various products depending on relative volatility of the hydrocarbon components. In MRPL, three Crude Distillation Units are operated to meet the refining capacity of 15 MMTA. 

Secondary Processing Units receive feedstock from Crude Units and upgrade it to the value-added products. The main secondary Processing Units in MRPL are

  • Hydrocracker Units 
  • Continuous Catalytic Regeneration Units 
  • Isomerization Unit 
  • Gas-oil Desulphurization Unit 
  • Petro fluidized Catalytic cracking Unit 
  • Delayed Coker Unit 
  • Visbreaker Units 
  • Bitumen blowing Unit 
  • Mixed Xylene Unit 

These Processes add value to products from the Refinery and thereby increases profitability. Treatment of Units play an important role in removing impurities like Sulphur, Nitrogen and Metals from the products thereby meeting stipulated product specifications. The important treatment units in MRPL are: 

  • LPG/Kerosene Merox Units 
  • Diesel Hydrotreater Unit 
  • Coker Gas Oil Hydro Treating Unit (CHT) 
  • Amine treatment, Sour water stripper and Sulphur recovery unit 

The Scope of the Project is to carry out HAZOP study for all 82 units

  • Review the existing Engineering and Administration control
  • Review of Existing safety controls and Interlocks
  • Review of Standards and Statutory requirements
  • Review of consequences of failure of Measuring Instrument/Devices, control final element, safety system and control system

The main objective of HAZOP study is to manage project risk through early identification of potential hazards & operability problems and reduce the probability & consequences of an incident that would have a detrimental impact on living, assets and the environment.

Total number of recommendations identified from HAZOP session for 82 units were 1005 No’s which includes Hardware, Software, Document and Procedure updation.

  • Software type recommendation consist of
  • Transmitter Alarms, Deviation Alarms, Soft signal Alarms, implementation of Interlocks to existing and new system, Timer installation
  • Hardware type recommendation consist of
  • New PT installation, Mechanical lock, installation of NRV, valves
  • PID and SOP updation also considered as recommendation.