Associated Gas Utilization

Associated gas utilization and recycling have become the main challenge of the oil and gas industry in recent years. For many years oil and gas complex was the main source of environmental pollution through flaring associated petroleum gas. About 30% of the country's harmful emissions were produced by this industry. At the same time, the produced associated gas is virtually a by-product of oil extraction. Absence of adequate infrastructure for its gathering, treatment, transport and processing was the main reason of associated gas misuse..

Challenges

  • High energy intensity of oil and gas extraction
  • Low level of associated gas utilization
  • High environmental pollution
  • Increase of environmental fines by 5% annually
  • Necessity of long-term investments in APG utilization programs
  • Demand for efficient APG utilization solutions

Associated Gas Utilization Programs

Current APG prices render the construction of transportation and processing infrastructure unviable. However, flaring this gas leads to significant economic losses. According to the Institute of Energy Strategy flaring of 1 billion m³ of APG equals to more than $ 300 million. Since Russia has ratified the Kyoto Protocol that limits greenhouse gas emissions the APG flaring costs additional $ 3-5 billion driving oil&gas companies to seek for efficient associated gas utilization technologies.

Almost all oil&gas companies have implemented programs for energy conservation and energy efficiency. One of the most promising energy-efficient technologies in oil production is related to associated gas utilization and onsite cogeneration. Growth of electricity rates after the transition to the market economy constitutes about 15-30% per year. Therefore, the development of onsite generation becomes essential for oil&gas industry.

Power Generating Equipment and Innovations

Despite the existing demand for distributed power sources, the development of onsite generation was limited by substandard domestic infrastructure. Traditional generated equipment – such as industrial gas turbines, gas piston engines and diesel engines – often does not meet reliability and efficiency requirements of oil and gas facilities. In particular, small oil and gas facilities struggle to find generating equipment in the range from 10MW to 20MW. Previously, such enterprises have used large gas-turbine power plants with power output far exceeding their demands. Operation of these plants at low loads made them too costly to use. Another option was the implementation of aircraft or marine engines that were in the required power output range but had low efficiency and weak performance.

The use of gas piston engines at oil&gas facilities is often associated with issues related to fuel requirements and costly maintenance. Gas piston engines cannot run on low-quality fuel, especially with H2S contents higher than 0.1% without additional gas treatment systems, which significantly increases capital costs. Often, because of the high detonation risk gas piston engines operate at 40-60% of the nominal power output. This leads to increased maintenance costs and accelerated wear and tear.

Introduction of the world's leading practices in the field of heat and power supply to the Russian market including Capstone microturbines brought new possibilities for oil&gas sector. The new generation equipment is supplied ready for operation with high automation degree and excellent consumer properties. Capstone microturbines are designed for industrial applications.

Capstone microturbines vs. industrial gas-turbine units and gas piston engines:

Capstone microturbines vs. industrial gas-turbine units and gas piston engines

Associated Gas Utilization Solutions

One of the cleanest and most efficient ways to utilize associated gas of oil&gas facitlities is on-site cogeneration. Today, the majority of the largest oil&gas companies, including Lukoil, Gazprom, Tatneft, ITERA, TATEX and others, are implementing such projects. These projects became even more relevant in view of obligation to utilize not less than 95% of produced associated gas by 2012.

Capstone microturbines offer great opportunities for efficient associated gas utilization. Onsite power generation using virtually waste materials allows reduction of energy bills by 2-3 times compared to the utility rates and results in compliance with the environmental regulations and significant reduction of oil production power intensity. Onsite power plants based on microturbines meet the most stringent requirements for energy security and sustainability.

Environmental features of various generating technologies:

Environmental features of various generating technologies

Capstone microturbines can tolerate up to 7% of hydrogen sulfide in fuel.

Capstone microturbines in projects for APG utilization take great advantage through their capability of running on associated gas with variable composition and calorific value and 4-7% of hydrogen sulfide content. Special materials and design of microturbine engines allow feeding, for instance, associated gas without any additional treatment and eliminate any risk of damage unlike gas reciprocating engines that capable of running only on pipeline gas or purified associated gas with no more than 0.1% of H2S. Considering the above the maintenance costs of microturbine system are 3-4 lower when compared to gas piston engines. As a result, the payback period of Capstone microturbine power plants averages 2-4 years.

Benefits of Onsite Associated Gas Power Plants

  • Low cost of electricity and heat generation
  • Eco-friendly operation
  • Fast payback
  • Optimized energy costs
  • Oil production costs reduction
  • Increased energy efficiency

Practical Experience

600-kW microturbine power plant of Shigaevo preliminary water-removal unit, Alliance Oil Company

600-kW microturbine power plant of Shigaevo preliminary water-removal unit, Alliance Oil Company

BPC Engineering has more than 13-year experience in implementing associated gas utilization projects. Microturbine-based power plants operate on oilfields of the largest oil companies including Lukoil, Tatneft, Tatex, Itera, Alliance, etc. Today, these advanced associated gas utilization solutions prove their efficiency at various sites including an 8-MW power plant of the Rodnikovskoye oilfield operated by TNK-BP and a 12-MW power plant of the Vakhitovskoye oilfield operated by Orenburgneft. A 16-MW power plant comprising 8 advanced gas turbines was commissioned in 2010 at the Zapadno-Malobalykskoye oilfield (Russneft Oil Company). Capstone microturbines have been proving themselves at the Onbiyskoye and Pogromenskoye oilfields for more than 7 years. In October 2009 a 195-kW microturbine power plant was commissioned for utilization of associated gas produced by the Shemetinskoye oilfield (600 000 m³ per year). The plant powers pumps of reservoir pressure maintenance system allowing UralOil – the oilfield operator – to save more than 2 000 000 Russian rubles annually. An onsite microturbine power plant of the Vostochno-Sotchemyu-Talyyuskoye oilfield is fueled by associated gas with 1.15% of hydrogen sulfide without any additional treatment. Exceptional performance features of microturbines have been highly appreciated by oil&gas companies and today they are being widely implemented at various production sites including the Nikolskoye oilfield of Bogorodskneft, the Polaznenskoye, Malo-Usinskoye, Kustovskoye and other oilfields of Lukoil-Perm located in the Perm Region, the Garyushkinskoye oilfield of PermTOTIneft, etc. As of today, BPC Engineering has shipped more than 100 advanced gas turbines for associated gas utilization projects in Russia. The total power output of the shipped equipment exceeds 63MW with capability to utilize 190 mln. cubic meters of associated gas annually.