Oil & Natural Gas Corporation LTD. (ONGC) is India’s largest public sector energy company, employing over 33,000 people and generating approximately 70% of the country's domestic crude production.
The company is renowned for its transparency and corporate governance practices and frequently ranks highly in a variety of indexes, including Platts Top 250 (no. 11, 2017) and Forbes Global 2000 (no. 183, 2017).
revitalize assets and maximize efficiency
One of the company’s key offshore fields is the Heera Oilfield. Located in the Arabian Sea, roughly 70km southwest of Mumbai, the field has been operational since the mid-1980s and plays home to 19 offshore platforms, 161 production strings, 7 gas producers, and 58 water injection strings.
As part of ONGC’s commitment to the Heera oilfield, the company set out to revitalize its offshore assets and maximize production efficiency.
Key areas of development
Key to the revitalization was a revamp of the water handling system, including the filters, chemical injection
Key to the revitalization was a revamp of the water handling system, including the filters, chemical injection system, and, crucially, the platforms’ deoxygenation towers.
The lump sum turnkey project to revamp the Heera platform’s deoxygenation tower was awarded to HAL Offshore, an end-to-end solution provider and EPC contractor; with Eta Process Plant and Gardner Denver Nash supplying the completed deoxygenation package.
Crucial to Boosting Production Efficiency
Commonly used in both on and offshore production, water injection is a method of enhanced oil recovery that helps operators to stimulate production and maximize a wells recovery factor.
The technique involves the drilling of special injection wells into then flooding the reservoir with water, generating the pressure required to push oil toward the well.
Seawater
Although any source of water can be used, the most common and convenient source for offshore operations is seawater. As the purity of water can impact the effectiveness of using water injection, seawater must first be filtered and deoxygenated.
The filtration process helps to remove larger impurities and debris, such as shells and algae before the water is passed to the deoxygenation tower; where it is processed using a system of vacuum pumps and ejectors, separating dissolved oxygen from the water.
Deoxygenation
The presence of bacteria and impurities can cause production problems as well as block pores in the rock
Deoxygenation plays a vital role in enabling water injection, particularly when using seawater. The process is used to not only prevent corrosion and the build-up of sub-surface solids but also prevent the formation of sulfur-reducing bacterial colonies in flow lines.
The presence of these bacteria and impurities can cause production problems as well as block pores in the rock, impacting the amount of oil that can be extracted.
The Right Mix of Reliability & Efficiency
Renowned for reliable and efficient performance in the harshest conditions, Gardner Denver Nash was contracted to contribute to the deoxygenation package for ONGC’s Heera platform. Working with Eta Process Plant, the team at NASH proposed a TC11 two-stage liquid ring vacuum pump.
Built from super duplex stainless steel, the TC series features a conical porting design that provides improved water-handling capabilities.
Patented conical porting design
The patented conical porting design also allows the force of compression to counter the weight of the pump's rotor and shaft, working to minimize the load placed on bearings.
The TC series also utilizes integral two-stage rotors that can more effectively condense and recover/dispose of vapor.
Final delivery of the vacuum package
The package was successfully combined with ejectors and a separator, supplied through Eta Process Plant
Due to the material used in the construction of the pump, the final delivery of the vacuum package took just under 12 months. During this time, the pump pattern, component casting, and machining were completed on location at Gardner Denver NASH’s Indian production facility, with all components then being sent to the company’s South Korean plant for assembly and testing.
The package was successfully combined with ejectors and a separator, supplied through Eta Process Plant, and is due for installation and commissioning in 2019.
Experts in Liquid Ring Technology
With a long history and extensive expertise in designing, manufacturing, and delivering custom liquid ring vacuum pumps, only Gardner Denver Nash can provide you with the knowledge to develop a system tailored to your operations.
Providing a comprehensive product portfolio catering to a variety of performance and materials requirements, all Gardner Denver Nash systems are backed by a global technical service and support base.