I Harem. an :20 - - EMULSION SNILE - [mus-rm 0 sommutsmn 20n' f; .00? 200' . :00 gonad Fig. 25 In-Situ Bitumen Recovery By Steam Injection Schematic Source, [28] heat losses upward in the formation to the overburden, or downward from the formation the numerator of the steam to bitumen ratio will be increased. Conversely, as the tar sand grade bitumen) decreases, a larger amount of sand must be heated for each barrel of bitumen recovered. Thus, the denomi? nator of the steam to bitumen ratio will decrease. If the expected thermal efficiency is significantly reduced then a relatively large and economically significant amount of the recovered bitumen will be required for fuel. Atomic Explosion In 1958, a group headed by Richfield Oil Company [29] and in Imperial oil Limited and Cities Service Athabasca proposed'the tee: fiipg of an atomic bomb in the Athabasca oil sands. . Project Oil Sand - of their proposal to the U. S. Atomic Energy Commission (who woulaS the title Alberta. The pro action has been deferred by the Canadian Gover The location proposed was Pon Cr eek It was planned that a nine as shown in Figure 26. THEIAH SANDS 0F 33 Which would contain up to 1/2 the energY This energy presumably would reduce the caVitY- This bitumen, if suffic1? could then be produced in a convent would be drilled at the test site a fter Project Oil Sand was designed u51ng not been discussed in the open literature Gasbuggy (recovery of natural gas may rekindle interest in ProjeCt tlme the exPeriment could be much more Or MINING The alternative to an in situ Proces On (ORPORAHON PONY N03 Lu! 79?99: Elevahon l942' HORIZONTAL a VERTICAL. SCALE 0 I00 200 300 Fm I. May. I963 "ii, . I Formula Ior comEulml gm Doprh a! bunch 450 3J?Kllotons - 450 2 08 936 fur Formula for compulm! rodiul a! raw"! sou of 610:?: Dr!? 55 267' Joli Fay Shula R- 55 Winona512? Grand m: 50nd 598? Bani Graft Rapid: Sand MT Char-via Original will rocanry ll" . fJ 1\ ll II fund ton. contain. about! 50% to 907. o! ?llion yroducll Lm Comanch- I, 304 Frown \Imot radmuivu len- manna o! collapud Iholl 26 Proposed Nuclear Test For Bitumen Recovery Source, [29] Fig. 34 the viscos ional man as useful thermal energy_ the bitumen contained in educed in duction well which the blast ity Ofd heated an ner from a pro he blast. of nd as of 1958. It has The recent success of co by means of nuclear ex- Certainly: at the preSent designed. he data in ha since 1963: in New MeXl iticallY heme is to mine the tar rt them from their place in mation to a proceSSing pl?nt? extract the bitumen value, and dis_ pose of the waste sand. In order to support crude production in a plant of economically viahle . size, an immense mining operation is called for. the Great sing SC transpo the for For instance, Canadian Oil Sands (GCOS) project which produces 45,000 barrels per calendar day of crude re- quires a tar sand mining rate or about 100,000 tons per day- This 1 figure refers to the tar sand (ore) 2 only, and does not include the over? burden which must be stripped away 1 in order to expose the tar sands for mining. This mining rate is of the order of size of the largest mines in North America, such as the open pit iron ore mines of Labrador and Minnesota. Because of the large scale of mining involved, only open pit methods have been prOposed for the Athabasca tar sands. As noted above one important parameter of an open pit mining scheme is the over- burden ratio (the thickness of over- burden which must be scraped away to expose unit thickness of the ore body). For the GCOS project, the overburden ratio 18 approximately 0.4 Overburden ratios as high as 2.5?3.5 have been discussed but have not been seriously proposed_ I Because of the relatively low unit value of tar sand as an ore, g?ning and transportation costs must amo igorously minimized. This meanS: ng other things, that the feed muSt IECHNOLOGY