TECHNOLOGY
Jet-Powered Compressor a Success Cooper-Bessemer's combination of Pratt & Whitney J-57 engine with own compressor passes 8000-hr. test on gas pipeline A 10,500-hp. compressor unit designed around a J-57 jet engine by CooperBessemer Corp. (C&EN, Nov. 28, 1960, page 54) has proved its worth in an 8000-hr., 15-month test conducted by Columbia Gulf Transmission Co., a subsidiary of Columbia Gas System, Inc., of New York, N.Y. The unit pumped 205 billion cu. ft. of natural gas at a thermal efficiency of 25%, and with an initial cost much lower than that of older, conventional installations. So successful was the experimental run, Columbia Gulf has applied for Federal Power Commission permission to classify the RT-248 as an operational unit. Pending FPC approval, Cooper-Bessemer says it has orders for 32 more units from companies in the gas transmission field. The unit also shows signs of very good acceptance in other fields. Cooper-Bessemer has an order for a unit to handle petrochemicals. This process-type unit would have waste heat recovery arrangements to produce steam, further increasing the utility and thermal efficiency of the RT-248. In the field of power generation, Cooper-Bessemer says negotiations are in progress for units to take care of peak loads and to bear certain heavyduty loads. General Electric, a maker of jet engines somewhat similar to the J-57, offers a line of lightweight turbines for industrial use. However, a GE spokesman said primary efforts have been directed to applications other than in the pipeline industry. To make the RT-248 unit, CooperBessemer combined a J-57 jet engine, made by Pratt & Whitney'Aircraft division of United Aircraft Corp., with a two-stage centrifugal compressor (RF2B-30) designed by CooperBessemer. The J-57 is well known as a power plant for modern jetliners and military aircraft, and now has shown its practicality in adapting the thrust of jet engines to stationary industrial power. Practicality comes from the low ini48
C&EN
FEB. 19, 1962
JET-POWERED GAS TURBINE. A Cooper-Bessemer service representative, Bob Brown, records data near the power turbine end of the RT-248 unit
tial cost per horsepower. Initial cost is about $100 per horsepower for the complete factory-assembled package. Installation costs run from a normal figure of $5.00 per horsepower to $10 per horsepower in difficult locations. Total initial cost is $105 to $110. Older types of equipment had initial costs of $160 to $170 per horsepower. Fuel economy is comparable to regenerated gas turbines even without heat exchanger equipment. Thermal efficiency is 25%—average fuel consumption was 11 cu. ft. per hp.-hr. using a fuel of 927 B.t.u. per cu. ft. during the prototype run. Operation and reliability presented no problems. A jet engine in an aircraft is run only 1200 to 1400 hr. before overhaul, but a stationary installation, with its advantages of reduced thermal shock, lower operating temperatures, and reduced intake of foreign objects, can last much longer. The RT-248 was shut down only for periodic inspections and preventive maintenance during its 8000-hr. test. When required, the gas turbine can be
removed and a substitute installed in about six hours. The engine would be returned to Pratt & Whitney for overhaul. Remote control, important in gas transmission where unattended and remote operation can be useful, was tried earlier than scheduled, and found successful. Columbia Gulfs gas control center at Nashville, Tenn., 120 miles away from the test site at Clementsville, Ky., began remote operation in June 1961. Early evidence of dependability speeded up the changeover from manual to unattended operation. Noise, always a problem with jet engines, wasn't too objectionable with sound dampening equipment only on the jet turbine air inlet. Columbia Gulf says the noise level is less objectionable than that found near conventional industrial power plants. However, the unit could be silenced to residential levels with sound attenuation in the exhaust. This addition wouldn't be difficult or uneconomical, according to the company.
