U.S. Environmental Protection Agency
nmental Technolo
ET
Eductor Vapor Recovery Unit (EVRU™)
Tlie U.S. EPA Environmental Technology Verification
(ETV) Program's Greenhouse Gas Technology (GHG)
Center, operated by Southern Research Institute under a
cooperative agreement with EPA, has verified the
performance of the Eductor Vapor Recovery Unit
(EVRU™) manufactured by COMM Engineering, USA of
Lafayette, Louisiana. This technology is designed to recover
gas from storage tank vents and other low-pressure
hydrocarbon vent sources for utilization or sale. EVRU™ is
a closed-loop system designed to reduce or eliminate
emissions of methane, volatile organic compounds (VOCs),
hazardous air pollutants (HAPs), and other constituents
present in vent gas. Methane is a greenhouse gas, and HAPs
and VOCs have significant human health effects.
Technology Description and Verification Testing
EVRU™ is a non-mechanical eductor (or jet pump) that
recovers vent gas by using high-pressure motive gas to
entrain hydrocarbon vapors from low-pressure sources.
EVRU™ operates on
the Venturi principle
as its core element.
The ETV Program
conducted testing of
EVRU™ at
TotalFinaElf 's
(TFE) El Ebanito
exploration and
production facility-
near McAllen, Texas.
The facility handles
The COMM Engineering EVRU™ installed separation of natural
gas and crude oil
condensate product, gas compression, and gas dehydration
from wells within a 5-mile radius. The TFE facility's
existing dehydrated high-pressure natural gas pipeline
supplied the motive gas. The recovered gas can serve as fuel
onsite or be repressurized with a booster compressor and
injected into a natural gas transmission line for sale. Unlike
conventional vapor recovery systems, EVRU™ has no
moving parts to maintain, resulting in lower maintenance
costs and less operational downtime and, therefore, greater
vent gas recovery over the course of a given period.
EVRU™ was installed to recover vent gas from a battery of
seven storage tanks. Pnor to using the EVRU™, the TFE
site employed a conventional vapor recovery unit (VRU) to
recover vent gas from five fixed-roof condensate tanks and
two gun barrel tanks. The TFE operators reported that the
operational availability of the conventional VRU system
ranged between 85 and 90%. During downtimes, the vapors from the
atmosphere. For these reasons, the site elected to replace the existing
Oil and Natural Gas Production and
Its Regulatory Background at a
Glance
Oil and natural gas condensate storage tank
batteries at production and processing
facilities in the United States emit an
estimated 23.3 billion standard cubic feet per
year (bscfy) of methane. U.S. EPA
estimates that these batteries also emit 7,000
tons per year of FIAPs, and more than 22,000
tons per year of VOCs. Each of these
pollutants can have significant
environmental and health effects.
Methane is 21 times more effective at
trapping heat in the atmosphere when
compared to CO2 over a 100-year time
period. This physical property makes
methane an important contributor to global
climate change. The F£APs emitted by the oil
and gas industries include benzene, toluene,
ethyl benzene, and xylene (known
collectively as BTEX compounds), plus n-
hexane. These pollutants have a range of
carcinogenic and toxic effects on humans.
VOCs contribute significantly to ozone
formation and thus, to both human health
and environmental degradation.
In June 1999, EPA issued National
Emission Standards for oil and natural gas
production to address the effects of
pollutants emitted by the oil and gas
industries. Among other requirements, the
standards call for operators to install control
devices to reduce vent gas emissions from
certain storage tanks. EPA estimated that
120 storage tank batteries would be required
to install control devices. In addition, to
address emissions of methane from the oil
and natural gas industry, EPA has
established the Natural Gas STAR Program.
This program is a flexible, voluntary
partnership that encourages companies
across the natural gas and oil industries to
adopt cost-effective technologies and
practices that improve operational
efficiency and reduce emissions of methane.
storage tanks were vented directly to the
system with the EVRU™.
Gas recovery rates, annual gas savings, emission reductions, recovered gas values, and total installed cost were
verified during testing. Table 1 summarizes some of the performance data for EVRU™. The full verification
report can be found at http://www.epa.gov/etv/vt-ggt.html#ogi titled COMM Engineering. USA Environmental
Vapor Recovery Unit (EVRU).
The ETV Program operates largely as a public-private partnership through competitive cooperative agreements with non-profit research institutes. The
program provides objective quality-assured data on the performance of commercial-ready technologies. Verification does not imply product approval or
effectiveness. ETV does not endorse the purchase or sale of any products or services mentioned in this document.
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Table 1. Selected Performance of the Verified EVRU™ Technology
Average Gas Recovery
Value of Recovered Gasa
Total Installed Cost of EVRU™ at Site
175Mscf/day
$650,000/year
$108,000
Other Parameters
Annual Gas Savings
Annual Reductions of:
Methane
HAPs"
Other Hydrocarbons
Compared with no recovery
system in place
64 MMscf/year
32.1
1.5
30.1
Compared with the facility's existing
vapor recovery unit that achieves
an operational availability of
90% vent gas recovery
6.4 MMscf/year
3.2
0.2
3,6
'Assumes an annual gas savings of 64 MMscf/year and a price of $5. 46 per Mscf (U.S. DOE. 2005. U.S. Natural Gas Prices. Energy Information Administration,
U.S. DOE. Accessed 15 September, http://tonto.eia. doe. gov/dnav/ng/ng_pri_sum_dcu_nus_a. htm), and 1 ,027 British thermal units per scf for typical purchased
annual wellhead price for natural gas for 2004.
b HAP compounds include the BTEX compounds, n-hexane, and Cg naphthenes, as defined in 40 CFR Part 63
Mscf = thousand standard cubic feet MMscf = million standard cubic feet
Selected Outcomes of the Verified EVRU™ Technology
Available sales and marketing data indicate that at least 11 U.S. facilities have installed the ETV-verified
EVRU™ technology. These facilities selected the technology, at least in part, because of the ETV verification
results and outreach. The estimated benefits of these existing installations include the following:
• Emissions reductions of 280 million standard cubic feet per year (MMscfy) of methane, 1,700 tons per
year of HAPs, and 21,600 tons per year of VOCs, with associated climate change and human health
benefits
• Increased recovery of natural gas with a potential economic value of approximately $6.3 million per year.
The ETV Program estimates that there are 12,670 U.S. storage tank batteries with the potential to benefit from
this technology. If 25% market penetration occurs, based on these two estimates,
• Up to 3,170 storage tank batteries could voluntarily install the EVRU™, in part because of
the technology's economic benefits.
• These installations could reduce methane emissions by up to 6 billion standard cubic feet per year
(bscfy), HAPs by up to 33,200 tons per year, and VOCs by up to 416,000 tons per year, with associated
climate change and human health benefits.
• The estimated economic value of the recovered natural gas (which equals the emission reduction
estimates listed previously) could equal up to $120 million per year.
The EVRU™ technology could assist up to 120 storage tank batteries in complying with EPA's
National Emission Standards.
References
U.S. EPA. 2006. ETV Case Studies: Demonstrating Program
Outcomes. EPA/600/R-06/001. January, (primary source)
http://www.epa.gov/etv/pubs/600r06001 .pdf
U.S. EPA ETV, http://www.epa.gov/etv.
Kirchgessner, David A., William A. Chatterton, and Robert
G. Richards. 2003. Vapor-Recovery Unit Passes South
Texas Field Test. Oil & Gas Journal. April 14.
http://www.sri-rtp.com/Current_Events/Joumal_Articles/OG%20Article%204-13-03.pdf
U.S. EPA Natural Star Gas Program, http://www.epa.gov/gasstar.
ETV Greenhouse Gas Technology Center
David Kirchgessner, EPA
kirchgessner.david@epa.gov
Tel: (919) 541-4021
Jeff Barghout, Southern Research Institute
barghout@sri.org
Tel: (919) 806-3456
EPA/600/S-07/029
August 2007
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