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<br />4 <br />~ <br />~ <br />~ <br /> <br />3.4 Retortinq and Uogracinq Wastewate~s <br /> <br />As was previously pointed out for oil shale processes which dispose of <br /> <br />the spent shale i~ a manner similar to that for Tosco II. all of the retorting <br /> <br /> <br />and upgradi~g wastewaters are treated ~o remove odorous, volatile substances <br /> <br />as part of the normal upgrading operations and then used to moisturize the <br /> <br />spent shale. ~he cost of wastewater treatment for this case is negligible. <br /> <br />However, fo~ p~acesses which dispose of the spent shale in a manner similar to <br /> <br />that far Paraho, the retorting and upgrading wastewaters should be treated for <br /> <br />reuse within the plant ra~her than, for example, evaporating the ~aters in <br /> <br />l:ned evaporation panas, which is ~asteful of water. one use of the wastewater <br /> <br />is as cooling tower makeup similar to that fo: coal gasification. ~he waters <br /> <br />evolved in retorting and that used fer upgrading are approximately 20 percent <br /> <br />of t~e ~ooli~g water m~<eup i~ the paraho Oirect process and approximately 12 <br /> <br />?ercent ~n the Pa:aho I~di:ect 9=ocess4, as compared ~o a range of 20 to 50 <br /> <br />percent :0= coal qasi=ica~ion (i.e. Eor coal gasi:ication the process condensate <br /> <br />is abou~ 20 to 50 percent of the cooling watar makeu~}. <br /> <br />~imited data is available on the quality of t~e retort waters. Table 3- <br /> <br />2, taken ~rom Refe=ence 6, shows the range of concentration of the major <br />constit~ents present in the :etort water from the Paraho cirect p~Qcess. The <br />retor~ water consists of the water separated f~om the crude shale oil and the <br />water condensed f:cm t~e cetor~ gases. Little data is available on the quality <br />of t~e upgraded wastewater. An analysis of the Tasco II retort water is given <br />in Table 3-) and represents a composite from data in References 2 and 11 (also <br />see Reference 4). Both :etort waters are high in ammor.ia and are quit~ dirty. <br /> <br />The Tosco II wat~r has a veri low <br /> <br />phenol content ~i~h ~~e o~qanic acics primarily <br />11 <br />b~odegradable The approximate composition <br /> <br />car~o~Ilic acids which are highly <br /> <br />of the combined retorting and upgrading wastewaters for the Tasca II process <br />is given in Table 3-4. The major components are mineral salts, phenols, amines. <br />orqanic acids and neutral oils~ <br />The quantities of water evolved in retorting and the combined foul water <br />4 <br />out of retorting and upgrading is given in Table ~-5. Tne quantity of upgraded <br />water is relatively constant for all three processes ranging from 167 gpm for <br />Paraho ulrect to 191 gpm for paraho Indirect. <br /> <br />6~ <br />