WSP10774 - Laserfiche WebLink

Home Browse Search

I-" 0) -J 0) of the first of five small retorts not scheduled to begin until October, 1979. In Table 4-1 prod~cts and plant par~~eters projected in co~h programs for commercial phase operation1,4 are compared. It should be noted t~at the Rio Slanco program assumes the likelihood of surface retorting of t~e mined-out shale to produce an additional 19,000 barrels/day or shale oil, whereas Oxy considers surface retorting an option to be examined at a later date. The Rio Blanco parameters shown are derived from their development plan for the case where the mined-out shale is not surface retorted. The similarity between L~e parameters of Table 4-1 is striking. BOL~ programs envisage producing a pumpable shale oil and not an upgraded product suitable as a refinery feedstock, as was envisaged in ~he surface retorting ?ro~racs discussed in Section 3. ?erhaps the principal difference in the plans from a ~ater ~agement point of view is in how the electrici~i Mould be generated f=om t~e retort off-gas. Cxy assumes the likelihood of using a combined ~/cle gas turbine system, while Rio Blanco assumes the likelihood of using an open cycle gas ~urbine system, which, ~~ough less efficient, is also less ~ater cons~~ti'l~ since no evaporative cooling is employed~ Table 4-2 compares the plant water balances from ~~e same development 1 1,4 d 1 1 d"f" "2,3,5 "" h " p ans an supp emer.ta mo ~ ~cat~ons It 15 l~portant to ernp as~ze that many of the flow rates shown in both balances had to be deduced or derived from limited data or information, as explained in ~ie footnotes :0 the tabl~~ It should also be emphasized that these figures rep=esenl: -=.he la-cest. "draft" values of the developers and must be exnec~ed to change as more test data becomes available and as plant designs become ~ore speci:ic. ~~at is, however, most striking about Table 4-2 are L~e marked differences in the assumed water dispositions and water needs be~~een the two plan~s, des?ite the si~larities of the plant parameters and products evidenced in Table 4-1. Also shown in Table 4-2 are the mine drainage waters projected for the C-a and C-b sites. These sites are both near the center of the Piceance Creek Basin where significant 9roundwater is expected. This groundwater is normally disc~ssed in terms of lower and upper aquifers separated by t~e mahogany zone of oil shale~ The occurence of mine drainage waters is not uniform through- out the basin~ ~he aquif~rs are in ~~e form of bowls wi~~ the greatest cepth near the center of the basin. Developments on the south end of the basin near -, '-