Dual-fuel drilling rigs or frac fleets are equipped with engines capable of operating on both diesel and natural gas, providing operational flexibility and potential cost savings. These rigs or frac fleets can alternate between fuels, enabling operators to select the most cost-effective or readily available option. They allow to replace up to 80% of Diesel with natural gas and also run on 100% diesel in the case that natural gas is not accessible.
Two primary reasons for substituting costly diesel with clean-burning natural gas are (a) using natural gas can significantly decrease VOC emissions from drilling and frac operations and (b) in most cases natural gas is considerably less expensive. However, one challenge in using high BTU natural gas from the wellhead is that it limits the amount of Diesel that can be replaced and unnecessarily consume valuable heavy hydrocarbons. In the absence of lean field gas, CNG is often used which can be more cost effective and provide lower emissions than Diesel, but also requires constant trucking from the next CNG plant.
The Solution: Fuel Gas Conditioning
Fuel Gas Conditioning (FGC) prepares natural gas for use in reciprocating engines and turbines powering drilling rigs or frac fleets by removing impurities like liquids, solids, and other contaminants.
The Problem with Traditional Fuel Gas Conditioning Methods
The problem with most FGC systems, such as J-T skids is that they do not deliver effective separation of heavy hydrocarbons, also known as natural gas liquids (NGLs) from the fuel stream. As a result, these valuable BTU-rich NGLs are combusted in the fuel gas, wasting potential profits, generating higher emissions, and reducing engine efficiency.
J-T skids provide a “good enough” solution in some situations, but they are vulnerable to freeze-ups, leading to process upsets and/or unplanned downtime. Unfortunately, the J-T process leaves a significant volume of NGLs in the fuel gas stream and is not capable of precise selectivity.
Case Study
The MaCH4 solution proved its value proposition in a rigorous pilot project with Iron Horse Midstream that was converted into a permanent installation by now.
In the Pilot, the MaCH4 NGL Recovery Solution was benchmarked against a J-T Skid. The Pilot employs a 4-bed PSA system with a compressor package delivering high-pressure feed gas to the MaCH4 unit. The MaCH4 unit generates a lean fuel gas stream for the compressor station engines and recovers significantly more heavy hydrocarbons remaining in a gaseous state for later processing at a gas processing plant.
MaCH4 Technology Beats J-T Skid:
- Eliminated engine derating, for a horsepower increase of up to 9% for maximum horsepower and throughput.
- Delivered cryogenic-like recovery performance without low temperature requirements, capturing 60% C2 and 95% C3+ heavy hydrocarbons on site, separating valuable NGLs, and boosting profits.
- Over
Innovative Technology for Fuel Gas Conditioning: MaCH4 NGL Recovery Solution
The performance and efficiency and diesel replacement ratio of dual-fuel -reciprocating engines used in drilling and frac operations is directly related to the quality of fuel gas.
The MaCH4 NGL Recovery Solution from Coldstream Energy is a PSA technology-driven solution for generating lean, pipeline quality fuel gas without the vulnerabilities associated with J-T skids. The MaCH4 solution uses patented, proven Pressure Swing Adsorption (PSA) technology that allows you to separate NGLs from the fuel gas stream and recover them downstream, instead of burning them up in fuel gas, allowing up to 80% diesel replacement and therefore provide a valid alternative to using costly CNG
Benefits of MaCH4
- Eliminate engine derating for maximum efficiency and horsepower
- Reduce VOC emissions from gas powered engines by separating heavy hydrocarbons from the gas stream.
- Increase revenue by separating NGLs from the gas stream for later recovery downstream, contingent on your gas gathering contract terms
