Document wXxxOZ8EDe6GdVg7GmwRENZJ

1 Arthur S Huey Generoilng Stotion, Oklohomo Gas and Elce- but boilers limit output to SI,000 kw. New gas turbino trie Co, hot two turbines with total capability of 36,000 kw, work in conjunction with the existing station hoot bale First commercial power produc ing gas turbine in U. S. A. will operate with existing steam plant. New capacity is obtained at lowest cost and improves overall heat rate What is almost certain to be the first gas turbine producing power com* mercinlly on a U. S. utility system has been purchased by Oklahoma Gas and Electric -Co from General Electric Co (Power, May 1948, p 94). A 3S00-kw simple-cycle unit, it will be installed at OG&E't Arthur S Huey Generating Sta tion near Oklahoma City, initial work probably starting about Jan 1, 1949. An abundance o! low-cost high-Btu natural gaa and favorable conditions for working the gaa turbine into the exist ing plant heat balance tnnke the instal lation attractive, extensive studies show. Station History. Byllesby Engineering and Management Corp (now Pioneer Service and Engineering Co) designed the original Installation at Huey Sta tion. Operation started in 1930 with No. 1 unit, a 30,000-kw Allis-Chaltners steam turbine, supplied by three ISO,* 000-lb-per-hr Springfield boilers. One of the three boilers was Intended as a spare. Operating conditions were 400 psig, 730 F, 2 in. Hg abs backpressure. Gas-burning equipment with fuel-oil standby was installed and building and draft provisions made for future instal lation of coal-burning equipment. Sub sequent operation showed that boiler output could be raised to 200,000 to 220,000 lb per hr with gas fuel but with proportionate drop in efficiency, in creased maintenance because of internal circulation difficulties and shorter life of superheater lubes. At the beginning of World War II it become apparent that additional sys tem generating capacity was mandatory with a minimum expenditure of critical material end manpower. With WP0 approval it was decided to add No. 2 unit, a 2Q,000'kw (25,000-kw capabil ity) General Electric turbine-generator, to take advantege of the proven reserve boiler capacity. Present station capa bility now is only 51,000 kw, limited by maximum heat ioput to boilers, although the turbine units have a combined capability of 56,000 kw. M (519) POWER September 1 waste-heat recovery on diesel engines. (4) Installation of a simple-cycle gas turbine, operating on natural gas, and - equipped with an exhausi-gaa-recovery heat exchanger. The first three methods would gain up to full capability, or 5000 kw additional from Iho steam turbines. However, this would be done at an increase In station heat rate. The fourth method, using a simple-cycle low-efficiency gas-turbine unit with heat exchanger, would produce a combined Motion capability increase In excess of 6000 kw, and if fully ex- -ponded by adding two more gas-turbine units would raise station capability a total of 15,500 kw.* The additional capability is produced at a heat rale tower then ihe present base sladop heat rate. Heat Balance. The elation, located on a lake, baa iu ^circulating woler cooled by natural evaporation and re circulation, augmented in summer months by a 13,600-gpm induced-draft Present hoot balance of Huey Stotlon includes three boilers and two turbines cooling tower. Annual average back with regenerotlvo feed heating. All boilers moy feed either of the turbines pressure equals 2 in. -Hg abs with out side temperature of 70 F, Fig. 2 shows present elation heat balance before, Capability 6000-Kw addiog to gaa turbine. In investigating gas-turbine use it was necessary to be sure the unit would funetion as required during the peak season. For the OC&E Co the peak, 9f J W BLAKE, Ofclehom Get and ffecfrJc Ce. end R W TUMY, Cenerel ffortrfc Co. demand comes in the hot summer months. A gaa turbine Is least attrac tive with high ambient temperatures since the compressor is a volumetric devica and delivered air weight varies inversely with tho inlet temperature. The installation proved justified for air temperatures which prevail during the summer. A precooler will be installed at the compressor Inlet, which will drop the inlet temperature about 25 F below ambient during the hottest weather. Mere Kilowom. Mokeup for the lake, supplied, in pert, by deep wells si 65 F, will do the precooling. Originally this water was put into the lake via generator air coolers and oil cooler* on the steam units. The quantity of water available will allow passing it through the gas- turbine precooler without impairing effectiveness of its original use. Fig. 4 shows estimated effect on gas-turbine capability of the. precooler with high ambient temperatures. Actual ambients in this area reach values shown In Fig. 5. Also shown is the inlet-sir tempera ture for the compressor. Gas-turbine exhaust temperature baa been limited to a maximum of 760 F by the manufacturer. This will be the limiting factor In loading the unit except 1. J^j^*** of 9Q> turbine will pass through heat exchanger heating feedwater that * st low ambients when generator rating bypassed the turbine dosed heaters. This raises steam-turbine kw output will be the limit The high exhaust-gas SopUmber 1948 (519) 45