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<br />N <br />00 <br />..., <br />W <br /> <br />from. about 8,500 MW in the low "EET" scenario to about 12,300 MW in the <br />high "without EET" scenario. :This com.pares with installed capacity as of <br />1976 of about 7,850 MW. Although not. explicitly reflected in the "with- <br />out EET" scenarios. (since it is not. a significant water-consuming activity), <br />coal mining may also be expected to increase in the Upper Basin. In part, <br />this will occur in association with the proj ect.ed expansion .of steam <br />electric power generatioo.facilities. In addition~ it is anticipated that <br />exports of coal to customers outside of. the Upper Basin will increase. <br /> <br />4-' <br />~.~~~~ <br /> <br />Water Requirements of Oil.Shale Facilities <br /> <br />Oil shale retorting involves two basic steps: (I) rubblization or <br />fracturing of the shale, and (2) heating of the shale to a temperature <br />sufficient to permit pyrolysis to occur. Typically, retorting processes <br />are defined as either surface, in-situ, or modified in-stu. In the <br />former, shale is mined and brought to the surface where it is placed in <br />a retort (a metal vessel) for heating. In the in~situ process, the shale <br />rock is.rubblized in place (i.e., underground) and the shale formation <br />itself serves as a retort, with heat being introduced into the formation <br />by one means or another. In the modified in-situ process~ a certain <br />portion of the shale rock (say 20 percent by volume) is first mined out <br />to create a void. The balance of the formation is then rubblized in <br />place and again serves as the retort. The shale that was initially mined <br />out would typically be processed in a surface retort. At the present time, <br />. surface retorting is the only process which bas been developed to com- <br />mercial or precommercial levels of performance. <br /> <br />"?)jl <br /> <br />In surface retorting processes, tbe retorting (i.e., beating) of tbe <br />shale yields four products: (I) spent shale, (2) condensable oils and tars <br />(sometimes referred to as raw shale oil), (3) noncondensable hydrocarbon <br />gases (sometimes referred to as off-gases), and .(4) water.l Thus, it, is <br />not retorting itself, but rather tbe handling and subsequent processing of <br />the spent shale and of tbe pyrolysiS p~oducts (oils, tars, and gases), that <br />lead oil shale facilities to .be. net consumers of water. .In particular, <br />water can be consumed in as many-a9 six different steps: <br /> <br />(1) dust control associated with mining and crushing of the sbale; <br /> <br />(2) scrubbing of off-gases; <br /> <br />(3) upgrading (i.e.,'hydrogenation and the associated. evaporative <br />cooling) of the pyrolysis oils and tars to produce a pump- <br />able crude oil suitable as a refinery feedstock; <br /> <br />(4) cooling, compa~tion, and disposal of spent sbale; <br /> <br />~.:'. <br /> <br />1. Water produced during retorting comes from the matrix of the rock itself 'r.'~:'. <br />(i.e., water of crystallization), from moisture on the surface of the rock <br />which was added by dust control operations, and from water of combustion <br />(i.e., water created by chemical reaction during retorting). <br /> <br />xXvi <br />