Pierre River Mine Project

MINING AND PROCESSING ERCB SIRS 3 – 38
Question No. 27
Section 4.1
Request Volume 1, Section 10.1, Page 10-131, Table 199-1, Supplemental Information
Responses; Volume 1, Section 10.1, Page 10-130, Figure 198-1, Supplemental
Information Responses.
Table 199-1 and Figure 198-1 show different values for natural gas consumed
for summer low-grade ore, summer average-grade ore, and summer high-grade
ore.
27a Explain the difference between the natural gas requirements identified in Figure
198-1 and Table 199-1.
Response 27a The thermal requirement and natural gas consumed data presented in Table 199-1
was incorrect. The data should have been identical to that presented in Table 9-2
in the May 2009 Pierre River Mine, Supplemental Information, Volume 1. The
corrected table has been reproduced here as Table ERCB 27-1 and is also
provided in Section 2.3, Supplemental Information Errata.
Table ERCB 27-1: Comparison of Thermal Energy Requirements
Thermal
Operating Scenario
Requirement
(GJ/m 3 Natural Gas
)
Consumed
(GJ/m 3 Process
)
Feed Grade
(wt% Bitumen)
Temperature
(°C)
Winter average-grade ore 2.44 0.86 10.9 40
Winter coarse high-grade ore 2.34 0.97 11.7 40
Summer low-grade ore 2.10 0.00 10.1 40
Summer average-grade ore 1.65 0.05 10.9 40
Summer high-grade ore 1.55 0.13 11.7 40
There is still a difference between Figure 198-1 and Table ERCB 27-1.
Table ERCB 27-1 includes total natural gas consumed, including gas consumed
by the combustion turbine, the duct burner and the auxiliary boilers. Although
Table ERCB 27-1 shows the total thermal energy required to heat process water
and to create process steam, the natural gas consumption is only for the gas
directly fired, i.e, the natural gas routed to the duct burner and the auxiliary
boilers. The natural gas routed to the cogeneration unit is not included.
If the energy recovered from the gas-fired cogeneration plant that is used for
steam generation were associated with its equivalent natural gas consumption,
the thermal energy requirements would appear as shown in Table ERCB 27-2.
April 2010 Shell Canada Limited 4-27
CR029