This document summarizes Mithun Chouhan's summer internship presentation at the Oil and Natural Gas Corporation Limited from May 1st to June 21st 2013. It provides an overview of ONGC, including that it is India's largest oil and gas producer. It then describes various processes at ONGC facilities including group gathering stations, heater-treaters, central tank farms, gas compression plants, desalter plants, and a project on reducing gas flaring and the associated estimated emission reductions.

1. SUMMER INTERNSHIP PRESENTATION
OIL AND NATURAL GAS CORPORATION LIMITED
(1st May – 21st June 2013)
MITHUN CHOUHAN|10CH10026
DEPARTMENT OF CHEMICAL ENGINEERING
INDIAN INSTITUTE OF TECHNOLOGY
KHARAGPUR
SURFACE TEAM

2. Introduction
Oil and Natural Gas Corporation Limited (ONGC) was
set up as a Commission on August 14, 1956. The company
became a corporate on June 23, 1993, which has now
grown into a full-fledged horizontally integrated
petroleum company, thus fuelling the increasing energy
requirements of the Indian economy.
 ONGC is one of Asia's largest and most active
companies involved in exploration and production of
oil.
 ONGC has produced more than 600 million metric
tonnes of crude oil and supplied more than 200 billion
cubic meters of gas since its inception.
 Presently it contributes 72% of India's crude oil
production and 48% of India's natural gas production.

3. Flow sheet
GGS
CTFGCS
DESALTERGCP
ETP
CWIP
Compressed gas to customers To wells via GGS Crude to refinery
Injected water to wellsEmulsion of oil, water
&gas from wells
3 kg/Cm² 40 kg/Cm²
40 kg/Cm²
2-3 kg/Cm² 4-5 kg/Cm²
5-10 kg/Cm²

4. GROUP GATHERIN STATION (GGS)
 Oil is received in GGS7(k) through 4” pipelines in
following headers.
 Group header
 Emulsion header
 Test header
 High Pressure header
 Headers are followed by separator’s from where
mixture of oil & water gets separated from gas.
 Gas is then sent to GCS while the mixture of oil &
water is sent to heater-treater for further treatment.
 Heater-treater consist of following chambers.
 Heating section
 Coalescing section
 Inlet degassing section
 Differential oil control
 Crude oil water content is reduced 50% sent to CTF
via dispatch pumps at 4-5 kg/cm² through 8’’ pipelines.

5. HEATER-TREATER
 Fire tube size 24”
 max working pressure 50 psi
 Heater size 8’x20’
 Transformer rated capacity 5kva
 The volumetric capacity of heater-treater is 800 tpd
and free water capacity is 125-400 m3 per day.

6. Central tank farm(ctf)
 Receives oil from all GGS treated as well as untreated.
 Consist manifolds to receive oil from GGS in controlled
manner.
 18 Storage tanks are available out of which
 Heat exchanger
 Heater-treater
 1-10 have capacity of 2000 m3 each.
 11 -18 have capacity of 10,000 m3 each.
 to heat crude oil from 34-35 ˚C to 42-43 ˚C before it enters HT.
 there are total 5 heat exchanger's in CTF.
 there are total 7 HT in CTF
 4 of capacity 250 m³ each and other two of 800 & 1000 m³.

7. Gas compression plant (Gcp)
 The main function of GCP is to compress the gas it
receives from GCS at 3 kg/cm² to 40 kg/cm² and send it
back to GCS.
 Compression of gas upto 40 kg/cm² is done in two
steps.
 Plant description
 Inlet separator
 Gas compressor
 Discharge separator
 Condensate drum
 Gas coolers
 It has a capacity of 150,000 m³/day
 It consists of 10 gas compressors and two reverse
osmosis plants .
 Raw water storage tanks
 Reverse osmosis plant
 Degasser tank
 Cation & anion exchange towers
 Cooling tower

8. Desalter plant
 The desalter plant receives crude oil with an average
BSW 10-15%. The output of the plant is up to 0.2%.
 There are five basic components which forms the
desalter plant. These are:
 Feed pump
 Heat exchanger
 economizer
 The desalter plant at Nawagam has 6 storage tanks
with capacity of 30,000 m3 each.
 Main heater
 Desalter vessel
 The desalter plant at Nawagam has 6 storage tanks
with capacity of 30,000 m3 each.
 Processed crude is stored in another tank and after
draining of free water is pumped to Nawagam CTF by
set of Booster pumps for onward dispatch to Koyali
Refinery.

9. Project
Study of Clean Development Mechanism
 Kyoto protocol
 CER
 Pre-Requisites of CDM
 Additionality constraint
 To be hosted by non annex-I
country(like India)
 Co development by host
country and annex-I country
 Validation by DOE and meets
CDM requirements
 Registration with CDM EB
 Verified & certified by DOE
Emissions
timeProject started
CER/
Carbon
credits

10. Project
Title : Gas flaring reduction project at Ahmedabad Asset ,
ONGC.
 Purpose
 Project Activities
 Brief explanation of how CDM project activity results
in reduction of GHG’s and why reduction would not
occur in absence of project activity.
 Title and reference of approved baseline methodology

11. Project
Estimated amount of emission reductions over chosen crediting period of (2006-16)
Annual estimation of emission reductions in tons of CO2e Vs Year

12. Thank You