Coalbed Gas Utilization Plan
of the Songzao Coal Mine Administration

Songzao Coal Mine Administration

It is estimated that the 8 gas reclaiming stations of the Songzao Coal Mine Administration will reclaim 8¡Á107 m3 gas in 2000, in which 3.6 m3 will be utilized and the rest 4.4¡Á107 m3 will be wasted and released to the atmosphere. In order to improve the environmental conditions of the whole area around the Coal Mine Administration and to make full use of the coalbed gas to serve for the society, we are actively seeking for reasonable and reliable ways of utilization of the coalbed gas.

1. Problems concerned with utilization
(1) Isolated storing and distribution systems. There are totally 6 inhabitant areas and 6 storing and distribution stations in the Songzao Coal Mine Administration. However, there are almost no liaisons between these stations, thus it is impossible to adjust and distribute the gas between these stations. Some stations can produce large amounts of gas and the excessive gas in these areas which cannot be used up will be wasted and released to the atmosphere. But some other stations produce small amounts of gas and the insufficient parts cannot be supplemented from other areas.
(2) The unreasonable pipeline networks with low peak adjustment capacity. The storing and distribution capacity of the 6 stations is 6¡Á104 m3 (see table 1 in detail). Except for a few stations with low capacity, most of the stations have capacity to meet the requirement. But the pipeline is not reasonable, which resulted in the gas insufficiency, even no gas in the far ends, so that the direct supply method have to be used (supply the users with gas from the extraction station directly). The direct supply will deteriorate the gas-supplying system, and make it impossible for the storing and distribution stations to adjust the gas supply (impossible to avoid the peak-time supplying and to store gas during non-peak time), which will result in a insufficient gas-supply frequently.

Areas extraction user Gas-utilization the capacity of gas-storing 
(Stations) quantity quantity gas container pressure
(m3/d2) (door) (m3/d2) (10 thousands m3) (Pa)ª¥
Datong area 3200 4569 30788 1.5 2600¡«4000
1018¡«2066
Shihao area 50600 2800 14868 0.5 1088¡«2068
Jingjiyan area 43100 572 10485 1.0 2600¡«4000
Yangdiwan area 24600 1500 10108 0.5 1088¡«2068
Songzao area 48000 3200 21564 1.5 2600¡«4000
1088¡«2068
baiyan area 23700 1900 10803 1.0 2600¡«4000
total 222000 14543 98614 6.0ª¥ 

2 Utilization plan
(1) The establishing of the long transportation system to supply urban inhabitants with gas.
In 1992, entrusted by Chongqing City Economy Committee, the Chongqing Institute of Coal Mine Design worked out the project proposal of the city gas supply using the gas in the Songzao minefield. The proposal follows a program of the middle pressure network and centralized transportation, and suggests the establishing of stations to connect with the Chongqing Nanping regional natural gas network and the importing of the gas into the network. In 1995, the designed gas supplying (or producing ?) ability was 81 million m3/d, with the 54.75 m3/d being served for Chongqing (1.5¡Á105 m3/d), and in 2000, 7.3¡Á107 m3/d will be provided to Chongqing (2¡Á105 m3 per day). The total investment is 23.04071 millions RMB, and the payoff period will be 16.16 year. Because the investment is huge and the fund has not been fulfilled, the project has not been carried out so far. Currently, although the natural gas supply of the Chongqing City has been relieved to some extent, it is still possible to implement this project as it can be favored by the National West Development Strategy.
(2) Supplying and bottling of the gas and serving for domestic use or vehicle consuming in the middle and small towns 
A total of 2 centralized compressing stations (located in the Songzao Mine area and the Datong area respectively) will be constructed, with the estimated investment of 30 million RMB. Plus 10 million RMB which will be invested for the high-pressure bottles and relevant equipment, the total investment will be 40 million RMB. The advantages of this plan include that, the bottling of gas are relatively flexible, there is a good adjustment functions on the gas-utilization during peak time and non-peak time, and the investment is low, with less risk and relatively short payoff period. The disadvantage is that, although the combined equipment for gas purifying is available in China and the price is relatively low, the high-pressure gas container is too heavy (the body of the container is 60kg) and needs to be replaced by the aluminum plastic alloy container imported from overseas.

The above is the main utilization way for coalbed gas in the Songzao coal mines, for which the Songzao Coal Mine Administration has made intensive investigations on the technical and economic aspects. The commercial development and utilization of the coalbed gas of the Songzao coalmines is a new economic growth point, and is the main direction of the coal product change and the structure adjustment. We are willing to collaborate with the companies at home and aboard to adopt multiways to develop and exploit the coalbed gas in the Songzao coalmines.