Page 383 - Air and Gas Drilling Manual

8-66 Air and Gas Drilling Manual
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Illustrative Example 8.7 Determine the bottomhole and injection pressures for
the example well given in the Illustrative Example 8.3 series. If the volumetric flow
rate of injected water is a constant 2 bbl/hr, determine the bottomhole and injection
pressures for the volumetric flow rates of formation water of 0 bbl/hr to 35 bbl/hr.
Assume a formation water specific gravity 1.07.
Using Equations 8-8 to 8-10 in the problem setup in Illustrative Example 8.3b
the bottomhole and injection pressures can be calculated for a constant volumetric
flow rate of injected water of 2 bbl/hr and the volumetric flow rate of formation
water of 0 bbl/hr to 35 bbl/hr. Figure 8-14 shows the increases in bottomhole and
injection pressures as a function of the volumetric flow rate of formation water being
carried from the well (while drilling a depth of 10,000 ft).

Figure 8-14: Illustrative Example 8.7 bottomhole and injection pressures as a function of
formation water being carried from the well (drilling at a depth of 10,000 ft).