A revolutionary new product that came into being after an engine operator answered a question on instrument gas is now poised to fully enter the compressor marketplace after the successful completion of its first pilot project and an independent third-party report.

Howard Malm, Chief Technical Officer with REM Technology Inc. (“RTI”), was at a gas compressor station when he asked the operator about what happened to the instrument gas.  When the operator replied that the gas was simply vented above the building to the atmosphere, Malm started to think there had to be a way to use the gas.

The result of Malm’s thinking was SlipStream™, a proprietary and patent-pending technology that uses vented combustible hydrocarbons as a supplementary fuel source for natural gas engines.  SlipStream™ is the latest addition to the REMVue® product family offering.  The system can be easily integrated into new or existing installations and used on engines from 100 to 4,000 horsepower.  It safely monitors and controls the addition of combustible fugitive emissions to a natural gas engine as fuel.

“SlipStream™ enables companies (operating natural gas engines) to use a resource that is otherwise wasted and provides a financial benefit besides significantly reducing the greenhouse gas emissions for a facility,” says Malm.

Using these vented hydrocarbons, which would otherwise be lost to the atmosphere, reduces the amount of fuel from the normal source.  As much as 50% of the main engine fuel can be displaced with vented sources by the SlipStream™ system.  The system can also easily be scaled down to less-than 10% if vented sources are small.

Vented hydrocarbon emissions are found at most compression facilities involved in the production, processing and transportation of natural gas.  Methane is one of the most common vented gases found at these facilities.  It is a greenhouse gas appreciably more detrimental than carbon dioxide.  “Methane used as fuel produces the least amount of greenhouse gas of any hydrocarbon fuel, but it (methane) is 21 times worse than carbon dioxide when vented to the atmosphere,” says Malm.

“Western Canadian data on vented methane emissions and leaks shows that if we can significantly reduce these emissions, we can reduce the greenhouse gas contribution from the gas production sector by well over 50%,” he adds.

The first SlipStream™ installation was a joint initiative between RTI, Power Ignition and Controls (“PIC”), CETAC-West and Alberta Innovation and Science.  The goal was to find a suitable location where SlipStream™ could be installed, run and tested under realistic conditions.  RTI and PIC searched for a natural gas producer interested in fuel gas savings and reduction of greenhouse gases; eventually contacting Petro-Canada.  Petro-Canada is a substantially-sized integrated oil company with five base business units.  Its North American Natural Gas business unit explores for and produces natural gas, crude oil and natural gas liquids in Western Canada and the United States Rockies.

It was apparent after the initial meeting that Petro-Canada was excited about SlipStream™ and its potential benefits.  “The philosophy of the SlipStream™ system was an opportunity to address venting (or fugitive emissions) for Petro-Canada,” says Randy Rosenau, Maintenance Coordinator for Petro-Canada’s Medicine Hat Production Operations.  “The thought of utilizing vented emissions as supplemental fuel which, in turn, increases our revenue makes very good business sense.  In addition to that, the greenhouse gas generated is reduced — which is a great benefit to the environment.  These considerations made the pilot worth pursuing and provided an inventive, simple solution to manage vented emissions.”

Following a safety review, Petro-Canada granted approval for a SlipStream™ system to be installed at one of its booster facilities northeast of Medicine Hat, Alberta.  The facility was chosen because of its pre-existing systems that would readily facilitate the SlipStream™ installation.  It had two Waukesha 3524 GSI engines driving Sullair PC40L screw compressors.  The SlipStream™ system was designed to collect instrument vent gases from both units and provide it as supplemental fuel to Unit 2, which already had a REMVue®– 500/AS system.

The SlipStream™ system at the Petro-Canada booster facility was commissioned July 27 and placed into service September 6, 2007.  Since that time, SlipStream™ has worked impeccably and has not caused any downtime for Petro-Canada.  It has also proven it can reliably and safely control the supplementary fuel delivery to an engine under a wide range of operating conditions.  The SlipStream™ gas provided 10% of the total engine fuel flow at 90% load under steady state operation.  Based on a gas cost of $7/GJ and an engine uptime of 97%, this translates to over $45,000 in fuel savings every year.  This reduction in vented emissions equates to over 2,700 tonnes/year of carbon dioxide equivalent (CO2(e)) — similar to the removal of an estimated 500+ cars per year off the road.  With the addition of the SlipStream™ technology, this site’s greenhouse gas emissions have been reduced to less-than 60% of its previous value.

“SlipStream™ did live up to our expectations,” says Rosenau.  “The flow through the SlipStream™ system is displayed both accumulatively and in real-time and because of this, we have actual numbers to report with respect to what hasn’t been vented to the atmosphere and what has been used as supplemental fuel.  This equates to more production at the sales receipt point.”

Having proven itself conclusively at site, the SlipStream™ system underwent an independent third-party study on November 6, 2007 by Accurata Inc. and Clearstone Engineering.  They reviewed the technology and evaluated the installation before performing field tests.  Steady state tests were performed at three load-speed combinations to cover expected operational variation.  Transient tests included a variety of unload, load, shutdown and start-up sequences where SlipStream™ handled a vent flow rate that changed by more than a factor of ten.  The SlipStream™ flow was stopped and started abruptly to simulate unexpected events including instrument failures.  SlipStream™ adjusted smoothly to the transient conditions with a “bumpless” engine response.

The study also performed steady operating tests at three loads and speeds with SlipStream™ enabled and then disabled. Both the load on the engine and the speed of the engine were varied, and the slide valve on the compressor and the process control valves would be utilized to produce the load steps.  The REMVue® electronic engine speed control would be utilized to control engine speed.  SlipStream™ worked “flawlessly” and delivered about 12 kg/hr supplementary fuel, which worked out to 7% at high speed and load and 18% at low speed and load of the total engine fuel from vented emissions.  Insofar as emission reduction were concerned, the test found that greenhouse gases were consequently reduced by 34% CO2(e) at high speed and load, and 55% CO2(e) at low speed and load.  In terms of carbon offset or credits that could be applied to another facility, the application of SlipStream™ technology reduced the greenhouse gas impact of the engine by 51% to 124%.  Over 10 fuel and exhaust samples were collected for analysis by the Alberta Research Council to verify the greenhouse gas estimations.

For part of the third-party study, Petro-Canada furnished an LDAR infrared camera to view the instrument gas vented to atmosphere.  LDAR infrared cameras detect gas escaping to the atmosphere. This technology was intended to qualify whether the SlipStream™ syste was using all the vented emissions for fuel or if some was allowed to escape from the vent.

“Both two-inch vent lines on the units were verified with the LDAR camera as well as a LEL monitor.  Presently, there are no fugitive emissions at 9-28 (the booster station),” says Rosenau.  “Reliability of the site has not been compromised.  The SlipStream™ system has performed 100%.”

In addition to its impressive showing in areas of seamless engine control, efficiency and emission reduction, SlipStream™ also has impressive safety methodologies in place.  Safety is a prime consideration in any REMVue® product. The third-party study verified that the SlipStream™ system could safely introduce the vented hydrocarbons into the engine as supplemental fuel.

The third-party study concluded that the SlipStream™ system performed the control and safety function as per the design.  The study also verified that the fuel savings and greenhouse gas reductions calculated by the SlipStream™ system were real and accurate.

While he has yet to review the conclusions of the third-party study, Rosenau was not surprised by the success of the SlipStream™ pilot.  “With the world-class professionalism and technical expertise of Spartan Controls, RTI, Petro-Canada Oil and Gas Operations and Maintenance, the success of the project was imminent,” he says.  “With that amount of talent, what appears difficult becomes easy.”

About REM Technology Inc.

REM Technology Inc. (“RTI”), a wholly-owned subsidiary of Spartan Controls Ltd., is a technology development company specializing in providing solid, proven optimization technology for reciprocating machinery.  RTI is committed to providing solid technology for reciprocating machinery that has a positive environmental effect by reducing emissions of CO, NOx and greenhouse gases (CO2 and CH4).  Power Ignition and Controls (“PIC”) is a division of Spartan Controls.  PIC provides a complete line up of engine and compressor controls, instrumentation and ignition system products