This video uses a combination of 3D and 2D Infographics to explain the process of Oil and Natural Gas Exploration. The drilling is to be done in the country Bulgaria. The video was made for Park Place Energy Corporation, U.S.A.
Park Place Energy is a U.S. public company engaged in exploration for oil and natural gas. Our management team has extensive international oil and gas experience.Our goal is to produce natural gas from coal seams in the Dobrich region of northeast Bulgaria.
Between 1965 and 1990 drilling was conducted in and around the area covered by the Block 1-11 Vranino license, and over 220 wells were safely drilled through the aquifers to the coal formations. From these activities, we know the location of the coal formations.
Although the license covers about 400 square kilometers, only about 700 square meters (being an area of about 100 meters by 70 meters) will be used for drilling operations. After the well is placed into production, the drilling area may be reduced. No activities will be conducted on or near environmental areas.
Our project in Bulgaria involves the exploration for gas from subsurface coal formations, or coal seams. Coal seam gas, also called coalbed methane (CBM), is a naturally occurring gas mixture that’s mostly methane.
Coal seam gas generally has more pure concentrations of methane (95%) than other natural gases found in sandstones or carbonate formations. Coal seam gas is formed by the same natural processes that create the coal seams that hold it.
By using the information from the wells previously drilled in the area, we can identify the depths of the local water aquifers to ensure that these aquifers are not damaged during drilling or production operations.
In the coal seams, the gas adheres to the surface of the coal (known as the matrix) and is also found in the system of naturally occurring fractures (known as cleats). The gas is trapped in the coal matrix and the cleats by water and ground pressure. Extracting the gas involves drilling into the coal seam and reducing the formation pressure primarily by pumping off the water in the formation. As a consequence of the lower pressure, the gas is released from the coal matrix and flows through the cleats to the well bore and then onward to the surface.
All of the casings will be cemented back to the surface, providing multiple mechanical barriers to protect the local water aquifers.
Coal seams are generally found at depths between 1500 and 2000 meters. The pressure integrity of the casing and cement is tested at every one of the casing before the final wellbore section is drilled through the coal seams. During the drilling of the final section, core samples will be obtained. Analysis of these core samples will allow us to determine if the coal seams produce coal bed methane. After testing is completed, we will install and cement the production casing. This ensures that the well is completely cased and cemented with no possibility of gas escaping in an uncontrolled manner.
Once the drilling procedure ends, the drilling rig is removed and a temporary wellhead is installed. A perforation gun is lowered to the coal seams. A high- pressure gas jet is released, piercing the casing and cement barrier to penetrate the coal seam. This process does not involve the injection of fluids, chemicals or sand which would occur with fracking.
Water and gas will then flow from the coal seams into the wellbore. The water will be piped to the surface in a center pipe, while the gas will travel in the space between the center pipe and the casing (the annulus).
At the surface, water will be deposited into storage tanks, then treated and removed from the drill site. Produced water will then be taken to a government licensed commercial disposal site for final treatment and disposal. Depending on the volume and quality of the gas, it may be piped to a local gas distribution system or compressed on-site into canisters as compressed natural gas (CNG).
The natural gas produced from coal seams is almost entirely methane, the same as the gas imported by Bulgaria. Natural gas is a substantially cleaner than coal, oil or burning wood. Natural gas produces 65% fewer emissions than coal per kilowatt hour and 25% fewer emissions than oil. Domestic production of natural gas will reduce the amount of gas Bulgaria must import and provide a cleaner, more environmentally friendly fuel for heating and electrical generation for the local economy.
We thank you for taking the time to learn more about coal bed methane and the opportunity it presents.