Abstract
The determination of operational parameters in the underground coal gasification (UCG) process should be considered in two aspects: first, the total coal in each UCG panel must be gasified and second, the calorific value of the produced gas should be acceptable. The main aim of this study is to present a model that meets these aspects and increasing the calorific value of syngas during this process. In order to achieve those aims, eight different increasing scenarios were devised for total gasification of coal per panel. These scenarios included: increasing oxygen injection rate (scenario 1), the amount of steam injection (scenario 2), operation time (scenario 3), cavity pressure (scenario 4), increase operation time and cavity pressure simultaneously (scenario 5), increase steam injection speed and oxygen injection rate simultaneously (scenario 6), increase in cavity pressure, operating time, steam injection rate and oxygen injection rate simultaneously (scenario 7) and also simultaneous increase in the operating time and steam injection rate (scenario 8). The results showed that for producing syngas with a higher calorific value, the following parameters had the most positive effects respectively: operation time, cavity pressure, steam injection rate and oxygen injection rate. Finally, the model validation was performed for the Centralia LBK-1 UCG pilot and the results showed that this model is very close to reality.
Highlights
Scientists are looking for different sources of energy because of limited oil and natural gas resources in the near future
The determination of operational parameters in the underground coal gasification (UCG) process should be considered in two aspects: first, the total coal in each UCG panel must be gasified and second, the calorific value of the produced gas should be acceptable
The results showed that for producing syngas with a higher calorific value, the following parameters had the most positive effects respectively: operation time, cavity pressure, steam injection rate and oxygen injection rate
Summary
Scientists are looking for different sources of energy because of limited oil and natural gas resources in the near future. Due to the specific chemical composition of coal, it has the potential to convert into oil and gas In the UCG process, the goal can be to produce any gas (e.g. hydrogen) according to the type of gas required by the industry or to produce syngas. The gas generated by the UCG process can be used for electricity generation, municipal gas production and it can be used in chemical industries such as methanol production, coal-toliquid process and natural hydrogen production (www.lin cenergy.com 2017)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
