QRA & HAZOP study at IOCL-Devanagonthi Bottling Plant

The IOCL-Indane LPG Bottling Plant, Devanagonthi was commissioned in 20th Feb 2001 and situated in Hoskote – Devanagonthi road, near Devanagonthi Railway station. The total LPG storage capacity is 6650 MT. The plant is spread over an area of 93.35 acres. The Indane Bottling Plant, Devanagonthi is basically meant for Storing, bottling and transport of LPG cylinders to Bangalore and nearby out station markets in Karnataka. Plant capacity has been designed to handle 300 TMTPA Liquefied Petroleum gas.

This Plant has the following units/Facilities,

1. There are 12 Nos. Tank Lorry unloading bays in two sheds (8+4).

2. The plant has total 3 types of storage vessels, 2 Nos of above ground Bullets with capacity of 150 & 100 MT, 2Horton sphere having capacity of 1400 MT each & 3 Mounded Bullets having capacity of 1200 MT each. The total storage of LPG is 6650MT.

3.  LPG from Storage vessels is pumped to filling shed for bottling using carousels. The system is capable of bottling various capacities of Composite cylinders (5 kg & 10 kg) and Normal cylinder (2kg, 5 kg 14.2 kg, 19 kg, 47.5 kg & 425 kg) using electronic filling machines.

4. Total 4 nos of LPG pumps of capacity 1- 85 m3/hr, 2- 150 m3/hr, 1- 165 m3/hr used for bottling operation

5. Total 3 nos of LPG Compressors of capacity – 300CFM each and 2 no’s New LPG compressor are under installation which is 300CFM & 150 CFM.

6. Total 7 nos of screw air Compressor of capacity- 300 CFM each.

7. Other facility such as STP Overhead conveyor, Access control system, Earthing interlock in TLD, New Store, ETP

Process description:

The Main process involved in the facility is receipt of Bulk LPG from Tankers, Storing the LPG in pressurized storage vessels and bottling the Bulk LPG in cylinders and distributing through distributor network. The below Block Flow diagram represent the Process involved in the facility.

The scope of work is to carry out HAZOP study for IOCL LPG Bottling plant, Devanagonthi. And this study covers the different sections, components, and equipment associated with the facility and process description.

The main objective of HAZOP study is early identification of hazards associated with process and operation to reduce the probability and lead consequences of an incident that would have a detrimental impact on Human, Facility, Properties, and Environment.

The Objectives of HAZOP are as follows:

  1. Identify Hazards associated with Process and Operation.
  2. Identify Credible causes such as manual / equipment / instrument failures that is likely to lead towards hazards.
  3. Qualitatively assess the risk(L/M/H/S) and provide recommendations to prevent/overcome the hazards if required. Which will be assessed using the qualitative judgment of likelihood and consequence ranking of an incident.
  4. In addition to these issues, HAZOP occasionally identifies items that could improve unit operations and efficiency of the process.

                As a first step the facility has been separated as 4 nodes based on the operation. And HAZOP study has been done for each node separately. The credible causes and consequences were identified for each parameter deviation. Then the available safeguards have been identified to mitigate the cause and consequences for each deviation and recommendations has been provided in the event of existing safeguards were found to be not sufficient. For this facility we found insufficient safeguards in the compressor unit for Pressure deviations, so we recommended to implement Pressure Indicator along with Pressure Transmitter. And as general recommendation, we have advised to update the P&ID regularly.

The scope of work for iFluids Engineering is to carry out QRA study for IOCL LPG Bottling plant, Devanagonthi. And this study covers different sections, components, and equipments associated with the facility and process description.

The aim of quantitative risk assessment is to evaluate the risk levels for personnel due to accidental release of hazardous components/materials due to loss of containment scenarios from the facilities and to analyse and exhibit that individual risks lie within the broadly acceptable regions. The main objective of the study is to evaluate the potential risk levels for personnel due to accidental release of hazardous materials and to exhibit that individual risks lies within the acceptable region.

The Objectives of QRA are as follows:

  •  To Identify Hazards and Major Loss of Containment(LOC) scenarios.
  • To Calculate physical effects of failure case scenarios which include Estimation of Jet Fire, Pool Fire heat radiation distances, Flammable gas dispersion distances, BLEVE and overpressure explosion impact distances.
  • Failure Frequency evaluation.
  • To quantify Societal risk around the particular facility.
  • Perform risk assessment to confirm that risk can be reduced consistent within the ALARP region/principle according to the UK HSE risk acceptance criteria.
  • Recommending measures to reduce risk and ensuring whether all risks are in ALARP or Acceptable region

The entire Facility has been divided into 23 isolatable sections. As this facility is handling LPG, the Major credible outcome events of Jet fire, Fire Ball, Flash fire & Overpressure Explosion have been identified and their impacts/consequences for each scenario have been determined using DNV PHAST 8.4.

Risk Analysis has been carried out with frequency outcome and frequency for the respective events using DNV SAFETI 8.4. From the results Most of the locations fall under ALARP region. In order to mitigate the risk few safety practices have been provided as recommendations. Especially advised to use portable LPG detectors in the Pump House area to ensure the early detection of release and conduct proper fire drills, functional test of control equipment.