QualityTonnes


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Who We
Are

Introduction What is a "Quality Tonne" Staff and Office Locations

The Carbon
Market

Introduction The Market Potential How the Market Works UNFCCC Process

QT's Approved
CDM Methodologies

Introduction AM0017 (Steam Efficiency Improvements in China) AM0020 (Water Pumping Efficiency in India) AM0023 (Reducing Gas Leaks in Pipeline Compressor Stations) AM0035 (SF6 Emission Reductions in Electrical Grids) AM0037 (Flare reduction and gas utilization at oil and gas processing facilities) ACM007 (Conversion from Single Cycle to Combined Cycle Generation) AM0048 (Elimination of Diesel Self-Generation) AM0052 (Hydropower Optimization)

Proposed CDM Projects
by QT and its Partners

Replacing SF6 as a Cover Gas in Magnesium Production

QT in the
News

QT Article in Env. Finance QT Article in Carbon Finance Point Carbon, CDM Monitor, July 15, 2004 Article on QT Point Carbon, CDM Monitor, June 14, 2005 Mott-MacDonald Press Release CCC funds buy QT, May 1, 2007

Areas of
Expertise

Power Sector Oil and Gas Sector Renewable Energy and Landfill Gas Energy Efficiency Sequestration

What QT can
do for you

Services: QT Baseline and Monitoring What else can QT do?

QT's Approved CDM Methodologies

AM0023 (Reducing Gas Leaks in Pipeline Compressor Stations)

The CDM Executive Board at its July, 2005 meeting, approved QT's methodology to reduce methane leaks in gas pipeline compressor and gate stations (now AM0023). This is the first methodology approved in the gas sector. This project in Moldova will use advanced leak-identification technology and is highly replicable around the world because of the huge losses from gas compressor stations. For example, according to the U.S. Environmental Protection Agency, the U.S. natural gas transmission network contains more than 279,000 pipeline miles. Along this network, compressor stations are one of the largest sources of fugitive emissions, producing an estimated 50.7 billion cubic feet (Bcf) of methane emissions annually from leaking compressors and other equipment components such as valves, flanges, connections, and open-ended lines. Data collected in the U.S. demonstrate that 95 percent of these methane emissions are from 20 percent of the leaky components at compressor stations. Thus a leak detection program can be extremely cost-effective.

To implement this effort, QT and its technical partners can do the following in compressor stations:

1. Initial Survey: In a system with many compressor stations, QT can have the company fill out a simple questionnaire providing the key information needed to identify the compressor stations with the highest probability of having the greatest leakage.

2. The Detailed Baseline Survey/Leak Screening, Measurement and Repair: The baseline survey is designed to determine the level of leaks and emissions - against which emission reductions will be calculated. During the baseline survey, a technical expert walks through the entire compressor or gate station and looks in the key areas to identify leaks. Some of the largest leaks occur in unit valves on blown down compressors, blow down valves and rod packings on pressurized compressors, pressure relief valves and other areas. For each leak, QT can do the following:

+	note the date of leak detection;
+	note the date of leak repair (some leaks may require additional equipment replacement, but generally the cost of leak repair is very small);
+	note the exact location of the leak;
+	measure the leak flow rate (volume per time);
+	note the measurement method in order to determine the uncertainty range of the measurement.

All data collected during the baseline and project implementation are entered into a database. The database is continuously updated during the crediting period, including when new leaks detected and repaired.

3. On-Going Monitoring Plan: The on-going monitoring plan is perhaps the most important part of the Moldova project and CDM projects in general. Because the CDM and JI process is so highly regulated, monitoring reports are scrutinized very closely by the independent verifier. Thus all data must be collected and the monitoring plan must be implemented in exact accordance with the methodology, or the verification report might not be issued - and the emission credits may not be generated. The monitoring plan is a critical component of any CDM and JI project and should not be overlooked.

4. Training of Staff and Equipment: As part of a project, QT can provide the equipment to conduct on-going leak measurements. Again, the technologies can vary, but QT prefers the use of the high-volume sampler. QT can conduct all the necessary training for staff in how to use the equipment. And QT will assist in making sure the monitoring plan is being followed exactly in accordance to the methodology so there will be few problems with the independent verifier.

High Volume Samplers capture all of the emissions from a leaking component to accurately quantify leak emissions rates. Leaked gas, along with a large volume sample of the air around the leaking component, are pulled into the instrument through a vacuum sampling hose. High volume samplers are equipped with dual hydrocarbon detectors that measure the concentration of gas in the captured sample, as well as the ambient gas concentration. Sample measurements are corrected for the ambient hydrocarbon concentration, and a mass leak rate is calculated by multiplying the flow rate of the measured sample by the difference between the ambient gas concentration and the gas concentration in the measured sample. Methane emissions are obtained by calibrating the hydrocarbon detectors to a range of concentrations of methane-in-air.

High-flow Sampler in Action

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