Improved Oil Recovery (IOR) methods encompass Enhanced Oil Recovery (EOR) methods as well as new drilling and well technologies, intelligent reservoir management and control, advanced reservoir monitoring techniques and the application of different enhancements of primary and secondary recovery processes. However, the present paper presents a comprehensive review of EOR status and opportunities to increase oil recoveries and final recovery factors in reservoirs ranging from extra heavy oil to gas condensate. It is well known that EOR projects have been strongly influenced by economics and crude oil prices. The initiation of EOR projects depends on the preparedness and willingness of investors to manage EOR risk and economic exposure and the availability of more attractive investment options.
India’s current refining capacity is 230 mtpa, including the just commissioned 15 mtpa IOC refinery at Paradip. The public sector accounts for 66 per cent of the total capacity while the private sector accounts for the rest 34 per cent or 80 MT.
Oil Refineries are the prime units to separate crude oil to different products. India is one of the largest oil3 importers. There are hundreds of Refineries in India, below mentioned are Major Refineries that could refine maximum of the total oil4 imports. The Coastal cities of India have major refineries and transport to other cities or towns of India.
Jamnagar Refinery is the largest oil refinery in India and also in the world, with daily production of 1.24 million barrels and it is owned by Reliance Industries, located in Gujarat.
Natural gas occurs deep beneath the earth’s surface. Natural gas consists mainly of methane, a compound with one carbon atom and four hydrogen atoms. Natural gas also contains small amounts of hydrocarbon gas liquids and non hydrocarbon gases. We use natural gas as a fuel and to make materials and chemicals.
Millions of years ago, the remains of plants and animals (diatoms) decayed and built up in thick layers, sometimes mixed with sand and silt. Over time, these layers were buried under sand, silt, and rock. Pressure and heat changed some of this organic material into coal, some into oil (petroleum), and some into natural gas. In some places, the natural gas moved into large cracks and spaces between layers of overlying rock. In other places, natural gas occurs in the tiny pores (spaces) within some formations of shale, sandstone, and other types of sedimentary rock where it is referred to as shale gas or tight gas. Natural gas also occurs in coal deposits and is called coal bed methane.
The search for natural gas begins with geologists, who study the structure and processes of the earth. They locate the types of rock that are likely to contain natural gas deposits. Some of these areas are on land and some are offshore and deep under the ocean floor.
If a site seems promising, an exploratory well is drilled and tested. Once a formation is proven to be economic for production, one or more production (or development) wells are drilled down into the formation, and natural gas flows up through the wells to the surface. In the United States and a few other countries, natural gas is produced directly from shale and other types of rock formations that contain natural gas in pores within the rock. The rock formation is fractured by forcing water, chemicals, and sand down a well. This releases the natural gas from the rock, and the natural gas flows up the well to the surface. Wells drilled to produce oil may also produce associated natural gas.
domestic production of natural gas in India is highly unlikely to keep up with the demand and the country has to rely on imports to meet its demand. Moreover, the domestic production in India has been concentrated over western and southern region of the country and in absence of adequate natural gas pipeline infrastructure the northern and eastern region of the country are gas starved. However, to satiate the increasing demand and strengthen the domestic gas distribution within the country, the government is planning to increase the share of natural gas in India’s energy mix to 15% which shall at large necessitate investments of at least USD 10.8 Billion for augmenting gas import and pipelines infrastructure.
The demand of natural gas in India is expected to depict a healthy growth trajectory till 2029-30. The highest demand will be from the power sector and it is expected to contribute ~ 36% to 47% of the total demand. The share of fertilizer sector is expected to drop from current levels of 25% to 15% due to higher growth registered in other sectors. CGD is expected to register fastest growth in the use of natural gas and is expected to contribute 11% of the total demand by 2030.
Another fuel that can also be a long term solution to India’s needs is Liquefied Natural Gas, given that it is a proven and commercially viable energy source. While globally LNG enjoys the status of being half-a-century old industry, in India it is still in the nascent phase courtesy the country’s absence from first round of LNG trade growth. However, over a short period of time the usage of LNG in India has shot up dramatically but in a haphazard manner.
Natural Gas Hydrates Programme
National Gas Hydrate Programme (NGHP) is of national importance considering India’s phenomenal growing energy demand. The programme was initiated in 1997 with a Steering Committee and a Technical Committee of NGHP for implementing the programme. Based on the review of seismic data by the Technical Committee, two areas in Indian waters, one along East Coast and other on West Coast have been identified as “Model Laboratory Areas” for further R&D work. DGH is the coordinator of the programme. Review of various projects under this programme is done by a Steering Committee set up by the Ministry of Petroleum & Natural Gas. OIDB has so far given grant to the tune of Rs.142 crore approximately against a sanctioned amount of Rs.208 crore approximately for various activities under NGHP.
Based on Geo-physical, Geological and Geo-chemical data, NGHP identified four offshsore areas for gas hydrate coring/drilling operations. Dedicated operations were carried out in these areas during April, 2006 to August, 2006 through a consortium consisting of Overseas Drilling Limited, Fugro, McClelland Marine Geosciences, Geo-TeK Limited, Lamont, Doherthy, Earth Observatory and scientists from numerous universities and national laboratories.
The NGHP efforts in Indian Offshore have led to the following:
- Conducted comprehensive analyses of gas-hydrate-bearing marine sediments in both passive continental margin and marine accretionary wedge settings;
- Discovered gas hydrate in numerous complex geologic settings and collected an unprecedented number of gas hydrate cores (more than 2800 m from 21 sites and 39 holes);
- Delineated and sampled one of the richest marine gas hydrate accumulations yet discovered in the world (Krishna-Godavari Basin) ;
- Discovered one of the thickest and deepest gas hydrate occurrences yet known which revealed gas-hydrate-bearing volcanic ash layers as deep as 600 meters below the seafloor;
- Established the existence of a fully developed gas hydrate system in the Mahanadi basin of the Bay of Bengal.