natural Gas: a fuel fit for the future?

August 26, 2022 by Abraham Dominguez

Strata Resources

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innovations that can transform flaring into profits

Strata Resources believes that the first step that needs to be done toward net zero is to avoid emissions as much as possible. Where emissions cannot be avoided, they need to be reduced as much as possible.

Flaring insights

According to the World Bank's Global Gas Flaring Tracker, reductions in flaring have plateaued over the last decade, marking a period of disappointing progress during a time of increased international focus on the urgency of greenhouse gas emissions reduction and the energy transition.

Global flaring alone from Oil & Gas Operators contributes 382.68 million tonnes of CO2 emissions per year. 143.50 million m3 of natural gas is burned into the atmosphere every year. When natural gas is vented straight into the atmosphere is even worse since methane can trap a lot more heat than carbon dioxide.

Why not make profits instead of burning associated gas? Imagine how much profit is being burned due to flaring.

One way operators can avoid massive flaring is by not surpassing their extraction capacity. With the rapid urge for immediate cashflow, operators sometimes override long-term business strategies such as maintaining plateau production rates, which causes oil reservoirs to fall below their bubble points quicker, which also means higher GORs. There is nothing wrong with opening the choke valve and earning quick profits by increasing oil production, however, investing in technologies that put associated gas into productive use should be considered in their field development strategies to reach net zero emissions in the coming years.

Onshore application

“Leaders in clean combustion and waste heat to power technology”

One onshore technology solution that can add a lot of value toward net zero emissions is the advanced incinerators called “clean combustion thermal oxidizers” from the Company Questor. These incinerators can collect waste gas from multiple gas streams, meaning that can take associated gas from multiple wells. Actual waste gas combustion occurs in stacks, also referred to as incinerators, thermal oxidizers, and combustors, without emitting any smoke, odor, or visible flames. Hot exit gases from the stacks are clean and readily available to utilize in other process improvements, such as utility heat and power generation. The thermal energy from the combusted gas in the incinerators can be used to generate power to run a wellsite or can be connected directly to the power grid and monetized.

Offshore application

Another technology that can significantly reduce emissions while generating power is Gas-to-Wire (GTW). The conventional way to transport most of the produced natural gas is via pipeline to the shore to be used as a fuel for power generation. Why not produce electricity from waste gas at the production facility instead of venting or flaring it?

The GTW technology refers to the process of generating electricity from natural gas at or near the field by employing gas turbines. The electricity generated is exported via subsea power cables to the local market. GTW can definitely lead to great results environmentally, but further commercial assessment must be carried out according to given field conditions.

GTW can play a vital role in mature hydrocarbon basins by maximizing recovery of remaining oil and gas resources. For instance, GTW technology can be combined with Carbon Capture Storage and Utilization (CCSU) approach. Instead of flaring or venting the associated gas, it can be treated at the production facility by a power plant, in which the gas combustion in the turbine can generate electricity to meet production facility power requirements or it can be delivered via subsea cables to the local market. The flue or exhaust gases produced from the combustion plant can be sent to a capture plant, where CO2 is captured, compressed, and injected underground for permanent storage or for enhanced oil recovery purposes. In the paper SPE-188845-MS, a simple GTW combined with CCSU scheme is presented as follows:

In the paper OTC-29852-MS, A feasibility study is carried out in the Pre-salt Province of Brazil between implementing GTW or installing conventional pipelines in order to withstand all gas production from the continuous development of the largest oil field ever found in deep and ultra-deep waters. The study shows that transmission of electricity is cheaper than transporting the gas via pipeline. The study suggests that the greater the distance from the shore, the more economical becomes the option of an electric cable when compared to the construction of pipelines. However, the cost of treatment and injection of CO2 is not included in the study.

As the world transitions to a cleaner energy future, the development of technologies such Questor´s incinerators and Gas-to-Wire can play a critical role in reducing the greenhouse gas emissions produced by the combustion of fossil fuels.

Abraham Dominguez

Professional petroleum engineer with relevant experience in drilling operations, well interventions and field development projects. His areas of special focus include emerging technologies, advancements in well engineering, reservoir engineering, and the energy transition.