Page 289 - Advanced Mine Ventilation

266 Advanced Mine Ventilation

15.3. Calculate the steady-state gas production from a vertical well for the following given
conditions:
k ¼ 0.01 darcy
h ¼ 6ft
m ¼ 0.02 cp
z ¼ 1.0
T ¼ 520 degrees R
r e ¼ 1000 ft
r w ¼ 0.25 ft
p e ¼ 1000 psi
p w ¼ 50 psi
3
If the gas content of coal is 600 ft /ton, how many frac wells will be needed to degas
a longwall panel, 1000 10,000 ft in 5 years?
Hint: the total gas production declines by a power law (Eq. 15.2) with the value of n
equal to 0.8.

References

[1] Thakur PC. Advanced reservoir and production engineering for coal bed methane. Elsevier;
2017. p. 210.
[2] Thakur PC, Poundstone WN. Horizontal drilling technology for advance degasification.
Mining Engineering 1980:676e80.
[3] Thakur PC, Davis JG. How to plan for methane control in underground coal mines. Mining
Engineering 1977:41e5.
[4] Thakur PC, Dahl HD. Horizontal drilling e a tool for improved productivity. Mining
Engineering 1982:301e4.
[5] Thakur PC. In: Darling P, editor. Gas and dust control, SME mining engineering handbook,
Chapter 15; 2011. p. 1595e609.
[6] Thakur PC, et al. Coalbed methane from prospect to pipeline. Elsevier; 2014. p. 420.
[7] Thakur PC. Optimum widths of longwall panels in highly gassy mines e Part I, 11th U.S.
Mine Ventilation Symposium. In: Mutmansky J, editor. The Penn State University. PA,
USA: University Park; 2006. p. 433e7.