introduce "artificial upwelling" by pumping in nutrient-rich water through a tube in the cylinder's bottom, adding perhaps 2% of the container's volume per day and letting excess water overflow at the top of the cylinder. Among the subjects of study, a central place will go to construction of mathematical models simulating the results. If reliable models can be developed from laboratory and field experiments, CEPEX scientists may be able to predict effects of pollutants in the open ocean, Dr. Menzel notes. The mathematical models will have to consider all major compartments of the ecosystem, from phytoplankton and bacteria to carnivores, and the effect of pollutants on component parts. Simultaneously, basic biochemical and physiological laboratory experiments will be carried out to determine the nature of basic alterations in metabolic systems and mechanisms by which they occur. Simulation models will be constructed of energy fluxes and effects of pollutants within the marine food chain. CEPEX scientists hope to find, for example, whether one trophic level (level in the marine food chain) is more affected by a pollutant than others, and thus would be the critical link. Dr. Holm-Hansen points out that if tests on the full-sized containers are successful, the cylinders could be used for many other problems—for instance, in situ study of effluent from a nuclear power plant, pulp mill, or sewer discharge. "You could stick a bag or bags into the river, and test the effects in this controlled environment," he observes. Marine organisms are very sensitive, he notes, and it is very hard to culture phytoplankton in the laboratory. "Besides," he adds, "you want to know the effects on organisms in the water, not in a controlled lab environment which may be very different."
Occidental develops low-cost SNG route A privately funded process developed for producing pipeline gas from coal is the latest entry in the substitute natural gas (SNG) sweepstakes. Technology originally developed for production of liquid fuels has been adapted tô the manufacture of SNG by Garrett Research and Development Co., Inc., a subsidiary of Occidental Petroleum Co. In a two-year development program the company and its development partner, Colorado Interstate Gas Co., have successfully tested in the laboratory a lowpressure (50p.s.i.g.) pyrolysis system. The Garrett process is based on the concept of partial gasification of coal in which the optimum yield of methane and other hydrocarbons is obtained by rapid pyrolysis of pulverized coal. Resi-
dence time in the pyrolyzer is less than two seconds, thus preventing any major cracking of the hydrocarbons in the gas product. Because of the special arrangement of process equipment, air can be used as the oxidizer for the pyrolysis without nitrogen's accumulating in the product gas. This method eliminates the need for either an inert heating medium, such as ceramic pellets, or an auxiliary oxygen plant. The gas produced in the Garrett process pyrolyzer has a heating value in the range of 600 to 650 B.t.u. per s.c.f. This gas may be upgraded using conventional hydrogénation and methanation steps to produce an SNG with a heating value of about 1000 B.t.u. per s.c.f. In addition to methane, carbon monoxide, hydrogen, and a small amount of carbon dioxide, the new process produces about 14% C2+ gases which are mostly ethylene. Optimization of the process for ethylene production is a major objective in Garrett's plans for future development. In addition to bench tests, Garrett has also completed pilot-plant tests with a coal throughput of 50 pounds per hour. The pilot tests confirmed earlier bench tests and provided enough encouragement to proceed to a larger demonstration plant.
Pilot tests of new coal-to-SNG process have confirmed earlier bench work
For your custom chemicals think Cordova
CORDOVA CHEMICAL
A DIVISION OF AEROJET CHEMICAL CO. Cordova Chemical, P.O. Box 13400 Sacramento, California 95813 (916) 355-5000 or 3 Hastings Road, Marlboro, New Jersey 07746 (201)536-4700
Dec. 17, 1973 C&EN
23
/
EVANS
THIOL·
ACETIC
ACID Specialty Thiolating and Mild Acetylating Agent RX + CH.CSH
»-CH,C-SR
*• RSH
,0 ,0 R-CH=CH, + CH,C'-SH-*- CH.C-SCH,CH,R-»» RCH.CH.SH
RNH.+CIW?- SH
•*-CH,(f-NHR + H i
OTHER THIOL ACIDS AVAILABLE THIOLBENZOIC DITHIOLTEREPHTHALIC Samples and literature containing eight pages with over one-hundred references available on request.
C H E m E T I C S , 90 Tokeneke Road Darien, Connecticut 06820 Phone: 203-655-8741 Cable: EVANSCHEM TWX: 710-457-3356
24
C&EN Dec. 17, 1973
\T\C
To eliminate bias in assessing the commercial possibilities of the new process, Garrett retained Lummus Co. as an independent evaluator. Accord ing to Donald E. Adam, a group leader at Garrett, the Lummus study indi cates that the Garrett process is signif icantly more attractive economically than competitive processes such as the familiar Lurgi process, which is now being considered for SNG production in the western U.S. This is true, says Mr. Adam, even when all of the cur rent and proposed Environmental Pro tection Agency emission regulations are taken into account. Another problem, particularly vexing in the western U.S., is availability of enough water to operate a process on a commercial scale. The Garrett process, when scaled up to a 250 million s.c.f.d. plant, will use no more than 3000 gal lons per minute of water. There is in tensive use of air cooling wherever pos sible. Also, no water discharges from the plant other than that from evapo ration and, consequently, there is no ground water pollution, according to Mr. Adam. Mr. Adam believes that the Garrett process is ideally suited for integration with a large power plant. In the case of a 1200-Mw. western power plant that would be fired with 5.4 million tons of coal per year, the Garrett process could produce 250 million s.c.f.d. of SNG for pipeline use and also deliver enough hot, pulverized char from the pyrolyzer to generate 1200 Mw. of electricity. The proposed integrated plant would eliminate the need for the power plant to have separate coal handling and grinding facilities, at the same time re ceiving a very-low-sulfur char. Total capital required for a Garrett gas plant is estimated to be about $309 million in the Colorado area. This in cludes equipment necessary to upgrade basic gas from the pyrolyzer to SNG. The capital required for a comparable Lurgi plant is estimated by Garrett to be from $371 million to $432 million, depending on location. The total cost for gas service from the Garrett process is estimated to be about 94 cents per million B.t.u., compared to $1.13 to $1.27 per million B.t.u. for the Lurgi plant. Garrett now is planning to demon strate the new process in a larger plant with a coal throughput of 10 tons per hour. The scaleup factor from the pro posed demonstration plant to a fullscale commercial plant is about 12, a value within confidence limits for com mercial design. Assuming that the present development schedule is ad hered to, Garrett further expects to go on stream with a commercial plant within six years. Until now, all funds for the project have been provided by the developers. However, Garrett is now actively seeking participation from the gas utilities industry, the electrical utilities industry, and other potential partners.
SCIENCE MILESTONES - on TAPE from C&EN D Vitamin B-12—Total Synthesis Listen to Dr. R. B. Woodward describe his dramatic work D Vitamin B-12—Biological Aspects International experts discuss bio chemistry, biosynthesis, and mecha nism of action
-other Science Symposia on Tape also available from ACS— D The Energy Crisis Outlook for oil, gas, coal D Fuels for the Future—Hydrogen Experts discuss solutions to the energy crisis D Nutrition & Public Policy— Food Quality Govt., industry officials spell it out Π Chemical Engineering In Medicine —at the frontier of chemical engi neering Π Drugs Affecting Learning & Memory A hot topic in drug research Π New Solid Waste Disposal Processes New processes set to go commercial D Chemistry of the Moon-I Dr. Urey, t o p experts reveal findings
ABOVE INCLUDE
VISUAL
MATERIALS
ACS NonMembers members Cassettes only $ 14.00 $ 17.00 10% DISCOUNT if payment accompanies order Name
•
Address
Order from : American Chemical Society 1155 16th Street, N.W. Washington, D.C. 20036 ATTN: A. Poulos
