gas hydrate - CCOP

The by-product water quantity and quality of CBM under the control of valves, pipes, and
separator, may have a positive impact because it can serve through controlled management i.e.
pumping directly to agricultural fields. At the site of a production well, the equipment and
plant will have no significant effect on land use because only a few square meters are required
and also there is no need to reclaim. From the water quality result on Table 3, no water treatment
is required before water can be either directly utilized or disposed.
Table 3. CBM Water Quality Analysis
Parameters Analysis Results Standard
Water temperature (◦c) 32.22 ≤37
pH 7.10 5.5-9
Conductivity; milli-ohms/meters 326.11 ≤ 30,000
TDS: total dissolved solid; mg/l 2,020 ≤ 5,000
Salinity; mg/l 2,040 2,000-5,000
Mae Lamao
Production and observation wells
Three wells, one production well and two observation wells, were located in a straight line.
Major factors that were considered in well location included thickness and continuity of coal
beds, depth of coal beds and structural geology.
Final completion of the production and observation wells was commenced after drilling was
completed. This is the stage at which pipes are installed. For the depth interval above or
below the coal beds, blank casing was installed while at the depth interval where coal beds
occurred screen was installed to allow coalbed gas to flow into the well. Gravel packing was
placed from the bottom of the well upwards to 5 meters above the top of the coal bed. The
remaining section of the well upwards to the depth of 50 meters was clay plugged. A cement
plug was placed from the depth of 50 meters to the surface to prevent percolation of surface
water.
The depth intervals at which coal beds are found in both production and observation wells are
shown in Table 4. The enclosing strata are made up of mudstone, claystone, shale, sandstone,
conglomerate, breccia, and Quaternary unconsolidated clay-sand-gravel. The coal-bearing
strata are divided into an upper coal bed and a lower coal bed. The upper coal bed is found at
the depth of 261-270 meters (thickness 9 meters) and lower coal bed at the depth of 281-286
meters (thickness 5 meters). Between the upper and lower coal beds, sandstone and claystone
with a thickness of 11 meters are present.
New Energy Resources in the CCOP Region - Gas Hydrates and Coalbed Methane 137