With the proper engine design optimization, extracting natural gas from the ground can be a more efficient, cleaner burning process that results in lower emissions, says a Colorado State University professor who is researching engine technology used for natural gas gathering.
It is challenging for engine manufacturers to control emissions and engine performance at the wellhead because they can’t control the composition of the extracted natural gas, said Daniel Olsen, a mechanical engineering professor in Colorado State’s College of Engineering. The natural gas composition (relative amounts of methane, ethane, propane, water, carbon dioxide, nitrogen, etc.) varies widely between wells at different locations and at different times during the history of a well. The composition of natural gas strongly influences engine performance.
Olsen is working with Cummins Inc., a manufacturer of natural gas and diesel engines, to develop engine technology that enables engines to operate on a wider range of natural gas composition while still maintaining high efficiency, low emissions and peak performance. Cummins has provided an 8.3-litre engine from its Clovis, N.M., plant to Colorado State’s Engines & Energy Conversion Laboratory for Olsen’s research.
"It’s a real challenge for manufacturers and operators when the fuel properties vary," Olsen said. "We are designing and building a fuel blending system to test different compositions of natural gas so we can quantify the impact on emissions and engine performance variation.
"This testing will help Cummins with design specifications for engine applications that involve a variety of fuel compositions. We can produce data that will help them develop and specify engines for this application."
Cummins Inc., a global power leader, is a corporation of complementary business units that design, manufacture, distribute and service engines and related technologies, including fuel systems, controls, air handling, filtration, emission solutions and electrical power generation systems. Cummins has been recognized for its continued commitment to the environment, and part of Cummins corporate mission demands "that everything we do leads to a cleaner, healthier, safer environment."
"Working with the Engines & Energy Conversion Laboratory allows Cummins to further increase our understanding of the effects of natural gas fuel composition on engine performance and continue to improve both our analysis-led design tools and the products that serve our customers," said Robin Bremmer, Cummins’ Director of Engineering for High Horsepower Natural Gas Engines. "Moreover, working directly with the students allows us to assist with the important role that CSU plays in teaching students engineering fundamentals, while preparing them for real world technical challenges."
Additionally, Olsen is working with EnCana Oil & Gas Corp. (USA) on a separate project to reduce emissions and improve the efficiency of engines used at natural gas wells by using fuel and oil additives. Enhancing fuel quality may lead to reduced pollutant emissions and increased efficiency. Improving oil properties can reduce friction, increasing efficiency and reliability and extending the lifetime of an engine.
The work is also being performed at the Engines & Energy Conversion Laboratory on an 18-liter industrial natural gas engine. American Clean Energy Systems Inc. is providing the fuel and oil additives for the investigation.
"EnCana is always looking for innovative ways to reduce emissions and lessen our environmental impact. This project is one aspect of those efforts that will hopefully result in technology we can apply in the field," said Dennis Schmitt, an engineer with EnCana who is working on the project. He holds a bachelor’s and master’s degree in mechanical engineering from Colorado State.
The Engines & Energy Conversion Laboratory is the largest independent laboratory of its kind in North America. The lab, directed by Professor Bryan Willson, has been recognized as a leader in the area of developing new clean and renewable energy technology. Research at the lab has resulted in hundreds of new jobs in the clean energy industry, which are concentrated largely in northern Colorado.
"It’s research that’s applicable to current problems," Olsen said of the engines lab. "It also develops students who are getting unique hands-on experience by solving real-world issues, using state-of-the-art equipment."