A New Approach to Address the Global Problem of Flaring

In the oil industry, methane (a component of natural gas) is a byproduct of drilling. While methane has value, the process of capturing it on a site that is built for oil drilling is complex and difficult. The cost can be prohibitive, especially for the small to mid-size facilities that make up a large fraction of the industry.

Very large facilities can afford the equipment needed to convert some of the methane into methanol, a process that is typically done on a large scale, which makes it more cost-effective. Smaller companies have few options. Their primary means of preventing natural gas from escaping into the atmosphere is burning it off, called “flaring,” a process that releases carbon dioxide. Carbon dioxide, although much less harmful than natural gas, is still a greenhouse gas. And a major issue still remains: the wastefulness of flaring methane, an important natural resource.

Venkat Viswanathan, assistant professor of mechanical engineering at Carnegie Mellon University, is collaborating with Watt Fuel Cell—a Mt. Pleasant, PA-based manufacturer of solid oxide fuel cells—in a PITA-funded project to develop a conversion method that is practical and cost-effective for moderately-sized drilling operations. The issue has global significance. According to the United Nations, which has a “Zero Routine Flaring by 2030” initiative, every year more than 300 million tons of carbon dioxide are released into the earth’s atmosphere. In some regions of the world, the flaring can actually be seen in NASA satellite images. “It’s as bright as cities that are freely lit,” said Viswanathan.

The project is targeting an application that is not directly related to the company’s current product offering, “but the insight we’re getting is giving us information about potential, new markets and how to maybe bridge our product portfolio to a new opportunity, thus potentially expanding future market applications,” said Benjamin Emley, director of new technology and grants at Watt Fuel Cell

Viswanathan has a special interest in energy conversion and storage. He is developing an electrochemical cell that can convert methane gas to liquid methanol at intermediate temperatures of 200°C to 500°C. The intermediate temperature makes it possible to convert methane to methanol selectively rather than oxidize it completely. Using the new electrochemical cell “allows us to carry out a process that otherwise would be really challenging,” he said.

The electrochemical cells, which are startingto be prototyped, will be easily adapted to the amount of methane gas being released. “You can stack them,” explained Viswanathan, so the number of cells in use can be changed to fit the methane output, which varies over the life of a well. In the beginning, there tends to be a great deal of gas released, so numerous, integrated stacks of cells can be used. As the amount of gas tapers off, cells can simply be removed from the stacks without disrupting them.

“We have a very good idea of the material components that need to be integrated together,” he explained. The next step is to integrate them into a system, then demonstrate the system’s efficiency. As part of the partnership with Watt Fuel Cell, the manufacturer has provided substantial expertise in such areas as materials, materials processing, and modular development. “I think it has been a wonderful collaboration,” said Viswanathan.