While i am doing my final year project's report, and people demands who has asked me to write down about CBM, here i would like to write about this such of subject. Coal bed methane (CBM), one of the example from unconventional hydrocarbons which is started to take a role in energy sustainability in this world.
This figures show about the production process of CBM.
In the US, coalbed methane (CBM) production currently stands at 3.5 Bcfd, about 7% of national gas production. New emerging coal basins (Uinta, Raton, Powder River) have been brought on line while mature areas (San Juan, Warrior) have maintained production.
Over 15 Tcf of CBM reserves have been booked to date, requiring more than $4 billion of capital investment ($0.30/Mcf). CBM E&P is now being conducted outside the US in China, Australia, Poland, and several other countries. As coal producing country, Indonesia CBM resource can simply be identified but quality and deliverability have not been tested. It may have considerable potential as a new gas resource.
As a new alternative energy resources a sequential challenges will require serious, well planned, long-term efforts to ensure a success of CBM development. This campaign is designed for those looking for alternative energy business opportunity in Indonesia, exploration managers and technical experts to provide an early understanding of coalbed methane geology, production technology, regulatory requirement and potential market and economics.
Why Coal bed is unique?
Coal is a gas reservoir that responses predictably to a specific set of interactive physical properties (as other gas reservoirs). Coal is a self-sourcing reservoir, thereby fulfilling the requirement of Source rock, Reservoir rock and Trap.
Coalbeds are an excellent storehouse for natural gas. They can hold two to three times as much gas as a conventional sandstones reservoir at the same depth.
Challenge is locating areas of adequate permeability (several md or more ) in otherwise tight coal seams to produce this resource.
However, in general there is agreement that the world’s supply of conventional crude oil will peak between 2020 and 2030. Most experts do not consider he contribution of unconventional oil and gas of the kind discussed in this lecture, because it seems too speculative. However, it is reasonable to state that any assumption related to decline in oil production will result in increase in oil price is necessarily not correct as oil supply from conventional sources will be replaced by oil production from unconventional resources. This obervation implies that global peak oil production will probably be not achieved probably for another 50 years.
Due to small dimensions of the micropores, a large internal surface area exists within the coal matrix. When a methane molecule comes into contact with an internal surface, two storage mechanisms are possible. The first mechanism of entrapment occurs when the gas molecule penetrates the surface and resides within the molecular lattice of the coal. This is an absorption process. the second mechanism occurs when the gas molecule adheres to the surface. This is an adsorption process. Both storage mechanisms are theorized to occur in coal.
The adsorption process can be classified by the forces which cause the gas molecule to adhere to the surface. If these forces are chemical in nature, such as strong chemical bonding, then the process is chemisorption process. If, however, the forces are physical, such as electrostaic forces or Van der Waal’s forces, the process is a physical adsorption process. The major portion of the gas stored in coal exists as a physically adsorbed, molecular monolayer.
Theoretically, the physical adsorption process is reversible. In coal, hwoever, a small degree of absorption and chemisorption occurs along with physical adsorption. Consequently, a hysteresis effect is often observed between experimentally determined adsorption and desorption isotherms.
So why CBM is Potentially Important to Indonesia?
CBM is Completely new undeveloped natural gas resources (but also untested)
Large resource potential given Indonesia’s sizeable coal base Location onshore may be more favorable for market compared with LNG of Eastern Indonesia. It is potential for advantageous “Global Warming” credits should market in tradable emission options develop
Indonesia, for this ESDM has a target to explore this mentioning area.
Formations: Eocene Tanjung
Oligo-Miocene Talang Akar
Mio-Pliocene Muara Enim
Major Basins: S & C Sumatra
S Kalimantan (Barito)
E Kalimantan (Kutei, Berau, Tarakan
Plus several smaller basins.
Why we are trying to use CBM as a new alternative energy?
1. Oil & Gas Prices Trend
2. Horizontal / Radial drilling technology courses CBM exploitation cheaper and more certain
3. EOR Technology can be used to exploit CBM
(Nitrogen Injection can increase Methane recovery 50 %)
4. Processing Technology allows “Insitu Gasification”
5. Cryogenic Method (LNG) in gas transportation will solve
high cost in high compression of CBM as a consequence of Low Producing Pressure
In Indonesia itself, there are several companies which are starting to develop this kind of energy. Pertamina, Medco E&P, Vico Indonesia, Ephindo, and etc. have been starting to do this development project of CBM.
So why we are not trying this? to be develop in Indonesia :)
Source : Mr. Kartono Sani and Mr. Turgay Ertekin