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Show Sohio proposes 5,000 barrel-a-day for sand picaratf Sohio Natural Resources Co. has submitted a plan whereby the company would produce about 5,000 barrels of oil per day from Utah tar sands to demonstrate the technology and then scale up to 25,000 barrels per day by 1990. An offshoot of Sohio Petroleum Co., the company has been giving thought and considering technology to the plan since October 1977 without much fanfare. At that time, the State of Utah . Board of State Lands approved a "commitment to cooperative development plan" submitted by Sohio. The plan provided that Sohio would pursue the common development of tar sand deposits on leases located on Asphalt Ridge in Uintah County. The plan included a performance of additional ad-ditional geological work and preparation of a mining technology. An assessment of oil shale and tar sands development in Utah, published recently by the Utah Energy Office, points out that Sohio estimates at full production a processing plant would need about 103,200 tons per day (34 million tons per year) of raw tar sand. This is more than three times the total Utah coal mining output for 1979. The Asphalt Ridge bituminous sandstone deposit is located on a northwest-trending cuesta about 15 miles long. The real extent of the deposit is about 20 to 25 square miles. There are two to five separate pay zones with a minimum thickness of five feet. In-place resources at Asphalt Ridge are presently estimated to be 1,150 million barrels. An analysis indicates that this tar sand contains from 6.4 to 29 gallons of bitumen per ton of material. Sohio estimates its leases contain an average of 11.3 gallons per ton. Sohio has 1,508 acres of state oil, gas . and other hydrocarbon leases and 320 acres of free land for the cooperative development plan. Sohio has developed two bitumen extraction processes on a laboratory scale. The company tags its most successful the "Sohio Process." Technically it is described as a "continuous "con-tinuous counter-current, solvent-assisted, solvent-assisted, bitumen-extraction process." However, Sohio has been approached by other organizations which have bitumen extractions technologies they think are ready for field testing. Sohio and other technology developers are presently negotiation. There is a possibility that one or more of these other technologies will be tested with or in place of, the Sohio Process. Steps involved in the Sohio Process, are mining, conditioning, screening, extraction, recovery and up-grading. Sohio anticipates that tar sands mining on Asphalt Ridge will be done from a partially exposed pay zone averaging 36 feet in thickness. The . i'"" , Vernal "So' " 1..- PRESENT ...... : v f.. i., SOHIO f 1 tano irss 3 . : Srr r -"z. J sohio l-qd -- PLANT SITE 3inic mmmm-mmmmm ItltfllliMMI" company would use bulldozers equipped with ripper teeth to loosen the bitumen-ladened sand deposits. The loosened material would be removed by front-end loaders. Then fresh water is mixed with crushed tar sand and fed into a conditioner con-ditioner where mixing with sodium carbonate solution separates the bitumen from the sand. Screening removes the oversized material, which is returned to the conditioner. The tar sand "pulp" is introduced into the extraction column. Water, solvent and sand are mixed and separated from the hydrocarbon stream. The slurry of sand and water is 'separated. The sand is sent to the disposal and recovered water is pumped to a water tank to be recycled. The hydrocarbon solvent stream undergoes further processing to extract the solvent from the bitumen. Recovery is 99 weight percent of the bitumen originally present in the tar sand. The pilot plant is expected to produce one barrel of bitumen (42 gallons) per hour. The Utah Energy Office report points out that a market for raw bitumen already exists in Utah for paving asphalt. But with additional processing the upgraded bitumen can be produced into a more valuable product, thereby extending its market. Bitumen distribution would be handled by tanker truck during pilor plant processing. Sohio would use water for the pilot plant from a 3,600 acre-feet right from Green River. Sohio estimates the process would use about 3.5 barrels of fresh water per barrel of bitumen or 39.6 gallons of water per ton of tar sand. Recycling of water is considered an important feature of the Sohio Process. Sohio estimates water losses will be 1.03 gallons per barrel of bitumen extracted. Sohio estimates that it will accumulate ac-cumulate 0.87 ton of spent sand for each ton of tar sand processed. That would be about 90,100 tons per day or 30 million tons per year at full production. Upon completion of the pilot paint program, overburden removed during the mining process would be stockpiled for future reclamation. Reclamation would involve replacement of overburden over-burden and processed sand into the mined out area. That area will be graded as near to the original coun-tours coun-tours as possible and revegetated with Indian ricegrass, Utah sweetvetch, winterfat, Russian wildrye and alkali saction. Sohio anticipates the water recycling process will almost eliminate a need to handle waste water. Sanitary wastes will be handled by on on-site packaged system. No wastes would be discharged. Sohio's "phased approach" to develop tar sands on Asphalt Ridge would involve the design . and construction con-struction of a processing plant by the end of 1982. Scale up of the process and construction of a commercial facility is planned for June 1989, if all goes well. |
