Document Ev549wLjx3vzmdbMDMjO0do4L

c .n v* (k - yy Extension to RIVERSIDE STATION of The United Power Mfg. Co. ByC. A. BUTLER, This addition consists of a 28,571-kva condensing turbine-generator supplied United Light & Power Engineering & Construction Co. with steam at 825 lb, 825 F, from a single steam-generating unit fired with pulver ized coal and having a continuous slag ging furnace. The turbine design per mits steam extraction to the existing 400lb station header. The article reviews the preliminary engineering studies involved and traces the progress in design of steam generators is now 82,142 leva which, together wlthrthat of an older steam station and several small hydro electric plants, serves Davenport, la., Rock Island and Moline, 111., and the surrounding territory. History generating equipment since the initial Riverside Station is a comparatively new power plant, installation was made in 1925. it having been placed in service in 1925. The original installation consisted of four 1044-hp Heine boilers and one 25,000-kva turbine-generator. These boilers were of the cross-drum box-header type, designed for a maxi HE rapid progress which has been made in the de mum drum pressure of 440 lb per sq in., with combina Tsign of steam-generating equipment in a compara tion convection and radiant superheaters arranged to tively few years is shown by the development of raise the steam temperature to 700 F. A high-pressure the Riverside Station of the United Power Manufactuerconomizer and a steel-plate induced-draft fan were in ing Company. This station is located on the west bant stalled in connection with each boiler. The fuel-burning of the Mississippi River about eight miles north of equipment consisted of four 10-retort, 33-tuy^re under Davenport, Iowa. Its combined capacity of main feed stokers. There were four forced-draft fans, con- Fia. 1--Exterior view of Riverside Station RS-000232 1/17/02 NUECES ** EDITORIAL Coal Research With advancement in power plant practice the effi ciency of coal utilization has steadily improved, as mea provided in 1935 by the formation of Bituminous Coal Research, Inc., under whose sponsorship projects are now being carried out by several universities and by Battelle Memorial Institute. Much of this research extends be p il s sured on an input-output basis. Further improvement yond the laboratory into the field of coal utilization where upon the performance of the most up-to-date installa surveys are being made and tests conducted in actual in tions must be progressively less as the limitations inher stallations. The question of coal segregation has been ent in the steam cycle are approached. This is demon attacked, sizing has been studied and for the first time strated by the statistics issued by the Federal Power the reactions and behavior of coal on an underfeed Commission covering the generation of electricity for stoker have been ascertained under service conditions. public consumption. From 1920 through 1937 the The program is far-reaching and much still remains to be pounds of coal per kilowatt-hour steadily decreased from accomplished. 3 in 1920 to 1.43 in 1937, but during the last five years During the eighteen-year period, from 1920 through the reduction has been only from 1.47 to 1.43. This, of 1937, despite a three-fold increase in electric output, the course, is an average for nearly 3800 plants, the most consumption of coal by the plants previously mentioned efficient of which are far under this figure. Much re has remained practically the same. This has been due mains to be accomplished, however, in raising the effi partly to improved efficiency and partly to the inroads ciency of the poorer plants, particularly among indus of competitive fuels, particularly gas. In meeting this trials, to the level of the leaders in their class. challenge the coal industry through the promotion of re With further improvements in thermal performance search in utilization is rendering a service to the power limited, there is still opportunity for increasing the com plant field as well as to itself. mercial or dollar efficiency through the selection of the correct coal for the particular conditions, thereby sim R8-000233 1/17/02 plifying operating problems by reduced maintenance and outage. Credit for achieving the marked reduction in Steam Washing NUECES coal consumption per kilowatt-hour belongs to the de The extensive use of higher boiler pressures has been signers and operators of power plants and their equip accompanied by the necessity of providing clean steam in ment, but as an aid to further progress specific informa order to avoid troublesome turbine deposits--a condition tion on the behavior of different coals under various con seldom obtaining with pressures under three hundred ditions of burning is needed and would be welcomed not pounds. This has led to the wide use of steam washers only by the designer of equipment but also the user as a by means of which the steam is washed by the relatively guide to the selection of the most suitable equipment. pure feedwater and the solids entrained in the steam are With some six thousand mines in the United States reduced to a minimum. producing coals of various characteristics and sizes, and Many tests have been made on the purity of steam thus hardly any two power plants identical in design and op washed and have shown remarkably low solids content, eration, the great multiplicity and combination of factors ranging from 0.5 to 1 ppm when operating with very high involved becomes apparent. boiler-water concentrations. From this it should not be The chemistry of coal has long been studied and data inferred, however, that high boiler-water concentrations are available covering the analyses and other properties are always permissible, as this depends upon several fac of coals from practically all seams. Also, some operating tors including pressure, analysis of the boiler water, the companies have accumulated helpful information on the steam liberation per cubic foot of drum and the type of performance of certain coals by trials in individual plants. boiler. Therefore, each case requires individual con But, despite this, there has been a dearth of information sideration. on just what goes on during the process of burning these Several methods have been evolved for testing the various coals. purity of steam. Among these are evaporation of There is a growing appreciation of the desirability of the sample and testing by electrical conductivity. In the giving more attention to coal selection, predicated upon a former method considerable time is required and much knowledge of its behavior in storage, in handling and in care is necessary in order to avoid contamination, the furnace, its caking and clinkering characteristics and whereas with the latter the presence of dissolved gases the mechanism of combustion. This has been brought must be guarded against or corrections made for them. about partly by developments in power station design While it is possible to determine the purity of steam down and changes in operating practice and partly by the new to 0.5 ppm, or perhaps less, those experienced in making marketing situation resulting from application of the such measurements usually advise checking by two or National Bituminous Coal Act. three methods when the indicated purity islessthan 1 ppm. Constructive work in fundamental coal research has In the final analysis, however, the object is to reduce been conducted for some time at Carnegie Institute of the steam purity to such a figure as will avoid trouble in Technology and the U. S. Bureau of Mines, but an added operation. This should be the ultimate criterion of perimpetus to the solution of coal utilization Droblems was jarmnnrp nected to a common air duct serving all the boilers. Air as originally made, three boilers were required to carry cooled refractory settings were employed. the original turbine at full load continuously. It was found that the maximum continuous output of each boiler as originally installed was 90,000 lb per hr 1936-1937 Addition and that operation at higher ratings, even for short Increased load on the system made it necessary to periods, resulted in excessive furnace and stoker main generate an appreciable amount of power at the Moline tenance. steam plant, located farther down the river on the east In 1929 a second turbine-generator of 28,571 kva bank. Compared with Riverside, the economy of the capacity was installed. No additional boilers were Moline plant is poor and maintenance costs are high. put in at that time because the system load did not make The increase in load also indicated early need of increased it necessary to carry full load on both generating units capacity on the system. Modernization of the Moline simultaneously. About the same time one'of the boilers plant by installing a superposed unit was considered. was equipped with a water-cooled furnace. This change But investigations showed that it was more desirable to increased the availability of this boiler, as was expected, concentrate operations at the more modem Riverside and greatly reduced furnace maintenance. The re Station and maintain the Moline plant for power-factor maining three boilers were equipped with water-cooled correction and standby service only. furnaces in 1930 and 1931. Although the equipment at Riverside could not be The fuel burned on the underfeed stokers was princi considered obsolete, and the station was operating at a pally southern Illinois coal. In 1932 a strip mine was heat consumption of approximately 16,500 Btu per kw opened approximately sixty miles from the power plant. hr generated, it was obviously unwise to add new equip The coal from this mine could be delivered to the plant ment designed for the steam conditions of 440 lb per sq at considerably less cost than that then being used, but in. and 740 F, without giving serious consideration to it ran high in moisture and had a low ash-fusion tem the possibilities of more economical operation obtainable perature; hence it could not be successfully burned on with equipment designed for higher steam pressure and the underfeed stokers. temperature. The use of a high-pressure superposed In order to take advantage of this supply of low- unit exhausting to the 400-lb header did not prove at priced fuel, the stoker was removed from one of the tractive for several reasons. First, with 400 lb exhaust boilers, the water-cooled furnace was altered and two pressure, the capacity of a superposed unit using steam pulverizers were installed. Direct firing and the inter at 1400 lb or less at the throttle would be too small to mittent slag tap method of removing the ash were em provide the additional system capacity required. Fur ployed. To provide preheated air for the mills, a small thermore, the blading efficiency of so small a high-pres Ljungstrom air heater was installed with the gas passage sure turbine would have been comparatively low. It in parallel with the economizer. This equipment was was thought that there was insufficient operating ex placed in sendee early in 1933. With the increased fuel perience with pressures in excess of 1400 lb per sq in. to burning capacity, and the reduction in draft loss through justify consideration of a higher pressure in order to the economizer, as a result of diverting part of the flue increase the capacity of the superposed unit. Secondly, gas through the air heater, the steaming capacity of the due to the fact that a portion of the base load of the boiler was increased to 140,000 lb per hr. This installa system is carried by the hydroelectric plants, the new tion was so successful that a second boiler was similarly equipment would at times be required to operate at altered later in the same year. comparatively light loads. Finally, it would obviously In 1934 natural gas became available at Riverside. be impractical to make the superposed turbine-generator This was supplied on a typical "dump gas'1 basis, and available for use with steam from the 440-lb boilers. did not entirely replace coal as fuel. All the boilers were equipped for burning gas. The burners on the two The New Turbine-Generator boilers that had been provided with pulverizers were con Further studies, taking into consideration fuel cost, verted to combination gas and coal burners, and in the equipment cost, expected character and amount of load, other boilers gas was burned over the stokers. and other important factors, led to the selection of a With both pulverized coal and gas firing, the superheat 3600-rpm condensing turbine-generator designed for added to the steam in the radiant superheaters was re throttle steam conditions of S25 lb per sq in. and 825 F duced. Therefore these radiant superheaters were re total temperature. Specifications were drawn up re built not only to regain the lost superheat, but to raise quiring that the turbine should be designed for these the final stream temperature to 740 F. steam conditions, but should be able to carry full load, at By 1936 the increase in industrial and domestic use of reduced economy, with throttle steam of 400 lb and 740 F. gas had limited the amount available for use in the power The turbine selected is a 21-stage G-E tandem-com plant. This fact, together with increased system load, pound machine using impulse blading throughout. made it necessary to remodel the remaining two boilers Eighteen stages are in the high-pressure cylinder. There for pulverized coal firing, despite the fact that plans for are two rows of moving blades in the first stage and the additional boiler and turbine capacity were already other 17 stages in the high-pressure cylinder have one being made. The changes were similar to those pre row of moving blades each. The low-pressure cylinder viously made on the other two boilers. is of the double-flow type. There are nine admission As a result of the changes in these four boilers since valves in the steam chest. The eighth and ninth valves, they were first installed, they can now carrv both 100- which are used only when the turbine is operating with lb turbines at maximum emergence capacity, and three 400-lb steam at the throttle, admit steam directly to the boilers can carry both turbines at normal full load fourth stage. A fulcrum shifting device, actuated by capacity, namely, 20,000 kw each. In the installation the steam pressure at the throttle, is incorporated in the RS-000234 1/17/02 NUECE8 governing mechanism. At pressures above 500 lb the a pulverizer out of service for maintenance withou eighth and ninth valves are prevented from opening, and drastically reducing the capacity of the steam generatin the full range of the governor is made available for operat unit. Therefore, three pulverizers were finally selecte ing the first seven valves. At pressures below 500 lb of a capacity such that under ordinary conditions tw the governor is able to open all of the admission valves. would supply enough steam to carry normal load on th When the turbine is operating with 825 lb steam pres turbine. With three pulverizers in service ample ca sure at the throttle, all of the steam passes through the pacity is provided to take care of adverse fuel conditions. first stage. Inasmuch as the pressure in the first stage By providing more capacity than originally planned i chamber under the heavier loads rises above 400 lb, the forced- and induced-draft fans, it is possible to it was found practical to provide for extracting steam utilize most of the capacity of the three pulverizers under from this turbine into the 400-lb header when the high- normal fuel conditions, and increase that of the steam pressure steam generating equipment is in service and generating unit to 300,000 lb of steam per hour. the machine is loaded above 22,000 kw. The design of The boiler installed is a C-E bent-tube three-drum the turbine permits 166,500 lb of steam per hour to be type designed for a maximum pressure of 900 lb per sq extracted at 400 lb per sq in., but until a second 900-lb in. Its drums are of welded construction and the heat pressure boiler is installed, the amount of high-pressure ing surface in the boiler proper is 8020 sq ft. The super steam available will limit the extraction to 126,500 lb heater, which is located between the first and second per hr. banks of tubes, has sufficient surface (6400 sq ft) to raise Despite its versatility, this turbine has an economy the total steam temperature to 825 F when the output is under normal operating conditions, which is within one 112,500 lb of steam per hour. At higher outputs the per cent of that of a turbine not having these features of steam temperature is controlled through bypassing a large high-pressure steam extraction and the ability to portion of the gas around the superheater and thus main carry full load with reduced throttle pressure. Further taining the temperature at 825 F. more, the economy when operating on 400 lb per sq in. A 9480-sq ft continuous-loop economizer is located is better than that offered by any turbine manufacturer within the boiler setting in space provided between the when the machine installed in 1929 was under considera two rows of tubes constituting the last bank. A gas tion. bypass located entirely within the setting makes pos The main generator driven by this turbine produces sible partial bypassing of the economizer. This, serves 13,800-volt, 3-phase, 60-cycle energy. Its capacity is two purposes. At low ratings gas is bypassed so as to 28,571 kva at 70 per cent power factor. Excitation for increase its temperature entering the air heater and thus the main generator is provided by an exciter on the main prevent its being cooled below the dew-point in the air shaft of the unit and the excitation for this main exciter heater. This reduces the danger of corrosion and is, in turn, provided by a pilot exciter which is also plugging in the air heater. Since approximately one- driven by the main shaft. This eliminates losses in the third of the total draft loss occurs in the economizer, the generator field rheostat during normal operation. gas bypass can be used if necessary at extremely high Since the major portion of the power from Riverside ratings to reduce the draft required at the induced-draft Station is transmitted by overhead lines, it was neces fan under adverse conditions. The feedwater enters the sary to provide a source of power supply for the essential economizer at 212 F and is heated to 398 F at maximum auxiliaries independent of the main generators and the rating. The feedwater regulating valves are located main bus. The 1500-kw house-service generator driven between the economizer and the boiler drum to prevent by a non-condensing turbine, which was a part of the steam being generated in the economizer when bringing original installation, was inadequate to serve the en the boiler up to operating pressure. larged plant; hence, a 2500-kw house-service generator was incorporated in the new turbine-generator unit. This is located between the main generator and the ex citers. All of the auxiliaries in the station are supplied with power at 440 volts, 3-phase, 60-cycles, and the new house-service generator supplies power of these character istics direct to the house-service bus. The air preheater is of the Ljungstrom type, with its shaft horizontal. It is placed above the boiler and con tains 14,400 sq ft of heating surface. The air tempera ture is raised to 305 F at 112,500 lb per hr steam output and to 394 F at the maximum steam output of 300,000 lb per hr. The furnace is completely water cooled. It has a /Cq /Cq Steam Generating Equipment volume of 12,650 cu ft and the effective heat-absorbin surface in the furnace walls is 3825 sq ft. A steel cask; Since the new turbine could be operated at full load on encloses the entire furnace, boiler, economizer and steam from the existing boilers, only one 900-lb pressure superheater. The waterwall circulating tubes are lo boiler was considered. A boiler having sufficient ca cated within the casing behind the furnace tubes, and pacity to carry full load on the new turbine, without ex are protected from the furnace heat by insulation Ln traction to the 400-lb header, was first contemplated. addition to the protection afforded by the furnace tubes. Due to the character of the coal to be burned, pulverizers Fuel is fired tangentially by twelve burners, three in were the only type of fuel burning equipment considered. each comer of the furnace. One burner in each comer The steam generating unit offered originally had a is connected to each of the three pulverizers, so that one. capacity of 225,000 lb of steam per hour, and was fired two or three mills may be used as required without up by two pulverizers. As the coal at times contains ex setting tha tangential effect. In each burner provision cessively high moisture, a considerable margin in pul is made fOr burning gas as well as coal. Gas and coni verizer capacity was necessary to insure full boiler ca may be burned either individually or simultaneously. pacity under such conditions. Furthermore, with only one This feature is especially valuable because at times = high-pressure boiler, it was desirable to be able to take limited amount of gas is available, but the amount is no : 22 RS-000236 1/17/02 NUECES CC. 240.04 RS-000236 1/17/02 NUECES sufficient to supply the entire fuel requirements of the new boiler. The tubes in the furnace bottom are covered with cast-iron blocks. Ash is removed in viscous form through an opening fifteen inches wide at the back of the furnace floor, this opening extending entirelv across the furnace. The viscous slag drops into a water filled ashpit, where it is cooled to produce a cinder similar to the ash from a stoker. The ash is removed from the pit periodically by draining the pit and feeding the ash to the suction of an ash pump bv means of hydraulic jets. During the period when the ash is being removed, the slag dripping from the furnace floor is cooled by water sprays in the upper portion of the pit. The three pulverizers, each of 15,000 lb per hr capacity, \ are of the Raymond bowl-mill type. Each exhauster is / directly connected to its mill so that both mill and exhauster may be driven by the same 150-hp. 1200-rpm motor. The average heating value of the coal is 10,400 ( Btu per lb. In order to provide the best possible mill '' foundations, simplify coal piping and afford space on the operating floor, the pulverizers were located in the boiler room basement. Each is served by an independent coal feeder located on the boiler operating floor where it can be easily inspected and adjusted by the fireman. Boiler Auxiliaries The new boiler is served by a single induced-draft fan located above the unit. At maximum capacity this fan handles 212,000 cfm of flue gas at 407 F with a draft at the fan inlet of 17.2 in. of water. It is driven by a 900/400-hp, 720/514-rpm 440-volt, 3-phase 60-cycle motor, through a 42-in. variable-speed hydraulic coupling. load conditions, but driven by a constant-speed or a two-speed motor. The forced-draft fan, of 104,300 cu ft maximum ca pacity at 11.75 in. of water, is located adjacent to the induced-draft fan and air heater. Ibis equipped with inlet vanes and driven by a 300/125-hp, 1200/900-rpm motor. The blades of this fan are backwardly curved to produce a non-overloading power characteristic. Due to the size and comparatively low voltage of the induced-draft fan motor, an auto-transformer has been installed with proper control equipment to reduce auto matically the voltage at the motor terminals on starting, and also when the speed of the motor is changed. This it pos contrc full-si; smalle The by tw to th valve In cai produ the f Wher arrangement limits the maximum inrush of current to approximately 1500 amp. Two boiler-feed pumps, each of sufficient capacity to supply feedwater to the new boiler at maximum output are installed in the pump bay of the extension. Each is rated at 700 gpm against 2600 ft total head at 212 F. Double-suction impellers are employed throughout, thus insuring good hydraulic balance. Each pump is driven by a 700-hp 3600-rpm wound-rotor motor. The principal reason for employing this type of motor was to reduce the starting current. However, the motor con trols are designed to permit variable-speed operation of the pumps, in order to take care of varying load condi tions most efficiently. The pumps are designed for ap proximately 100 lb per sq in. greater excess pressure than required for maximum operation so as to provide for decreasing total available head due to wear between periods of overhaul. The variable-speed motors permit 40Ct operation at reduced speed when the pumps are in best condition, to maintain normal excess of boiler feed pressure over the drum pressure. The new boiler is equipped with complete Bailey air- operated combustion control equipment designed to maintain the best operating conditions whether the boiler is being fired with coal, gas or coal and gas in com bination. RS-000237 Valves and Piping 1/17/02 NUECES Carbon-molybdenum tubing, fittings and valve bodies are used in the high-temperature steam piping, and seat ing surfaces on all high-temperature valves are faced Fig. 3--Boiler room instrument panel with stellite. Where joints were required in the steam piping, 900-lb Standard flanges with small tongue and The speeds of the motor were selected so that the low- groove facing were used. All high-pressure valves speed winding may be used in normal operation when the greater than 2-in. are flanged, and small drain valves steam output of the boiler is below 226,000 lb per hr. were machined with socket ends for welding. The fan blades have abrasion-resistant steel wearing A novel arrangement of two reducing valves and one pads formed over the inside edge of each blade and tack- desuperheater was used to make the capacity of the high- welded to the outside edge. Stay rods in the fan wheel pressure boiler available to operate the 400-lb turbines. are protected by pipe sleeves. _The fan housing, inlet In order to insure maximum flexibility, two reducing boxes and gas ducts are made oversize to permit lining valves were installed. The valve which opens first has of these parts with concrete applied by means of a cement a venturi-type desuperheater installed at its outlet. gun. This concrete is reinforced with bars and wire The other reducing valve, which starts to open only after mesh securely anchored to the plates of the housing, the first valve is nearly wide open, discharges steam inlet boxes and ducts. These special features of con beyond the desuperheater outlet. The thermostat struction should greatly reduce maintenance caused by which controls the water to the desuperheater is installed erosion from fly ash. The hydraulic coupling was beyond the point where the discharge from the de selected rather than inlet vanes in order to reduce to a superheater join? the outlet pipe from the second re minimum the number of parts subject to erosion, and ducing valve. Thus the temperature of the steam to the because previous experience in other plants has indicated 400-lb header is always automatically controlled, but that the erosion of parts in a variable-speed fan is ap only one-half of the maximum flow of 300,000 lb of steam preciably less than in a fan operating under variable per hour passes through the desuperheater. This makes the: take bad heat pod bv Ii plac orig a tv rive aisl tur1 boi I put 1 ' it possible to use a smaller desuperheater which will control the steam temperature more accurately than a full-size desuperheater at low steam flows. Besides, the smaller desuperheater costs less. The reducing valves are air-operated and controlled by two pilot regulators. One of these pilots is connected to the 400-lb header and normally controls the reducing valves to maintain a pressure of 390 lb in this header. ,, In case of trouble in the 400-lb steam system which would produce an excessive steam demand on the 900-lb header, the first pilot will open wide both reducing valves. When the pressure in the 900-lb header drops to S00 lb boilers. Therefore the boiler room was extended two bays, using the same column spacing in both directions as was used in the original installation. This provided space for the new boiler and for a future boiler, both on the side of the firing aisle farthest from the river. The space between the firing aisle and the existing turbine room, which would have been used for two more boilers, if the boiler arrangement used in the original installa tion had been continued, was made a part of the turbine room. The new turbine-generator was installed in this space. The suspended parabolic coal bunker construction the second pilot, which is connected to the 900-lb header, takes control of the main valves and operates them as back-pressure valves to maintain the pressure in that header at S00 lb, but still pass to the 400-lb header that portion of the high-pressure boiler capacity not required by the high-pressure turbine. Building In the original installation the tour boilers were placed two on each side of a common tiring aisle. The original turbine and the second turbine were installed in a turbine room located between the boiler room and the river. The turbine shafts are all parallel to the tiring aisle; hence, after the second turbine was installed the turbine room was approximately 72 ft l inger than the boiler room. Despite its greater capacity, it was lAuud possible to put the new steam generating unit in a space the same size and shape as that occupied bv : of employed in the original installation was duplicated, using the same cross-sectional dimensions and the coal conveyor over the original bunker was extended to serve the new bunker. The height of the building extension over the boiler and bunker was made the same as in the original part of the building, and the section over the new turbine was made considerably lower. This method of extending the building for the new equipment not only reduced building costs, due to the decreased space required, but further reduced this cost because the construction was far enough from the river to eliminate the necessity of a cofferdam. In order to install the turbine and its auxiliaries in the space provided, the condenser was located with its tubes parallel to the turbine shaft. A single-pass condenser with 17,300 sq ft of surface, made up of 7/,-in. diameter tubes 20 ft long was selected, as a long narrow condenser was best suited to this arrangement. The condenser was - than its final position before the turbine foundation was unit share to some extent the advantages of a superposed built. The reinforced-concrete foundation was then turbine in increasing the economy of the older turbines. built around the condenser. After the turbine was 3. The new unit may be operated alone when the erected the condenser was raised to its final location and load is light. This would not be possible in a superposed attached to the turbine exhaust nozzle by welding. The installation and makes this unit much more economical entire weight of the condenser is supported by the tur under light load conditions than a superposed plant. bine exhaust nozzle. 4. The new unit may be operated with steam from Two horizontal circulating pumps serving the second the old boilers, thus making it unnecessary to install turbine were removed and replaced by two vertical pro more than one high-pressure boiler to insure maximum peller type pumps which were built into the existing 42- availability of the new turbine. This makes better in. suction pipes that had served the pumps removed. use of existing investment in lower pressure boiler equip The capacity of the pumps removed was approximately ment than is usually possible with superposition. 26.000 gpm each. The new pumps have a capacity of 5. The arrangement of turbine governing mechanism, 55.000 gpm each and can supply sufficient water for the piping and steam-pressure reducing and desuperheating condenser of the new unit as well as for the condenser equipment makes the capacity of the high-pressure which the horizontal pumps had served. Therefore boiler instantly available to supply steam to the 400-lb the expense of installing additional suction pipes was header in case of trouble with the high-pressure turbine, avoided, and no additional space was required for cir and also makes it possible to maintain the new turbine culating pumps for the new unit. in operation, without loss of load, with steam from the The resulting decrease in building volume required 400-lb boilers in case of trouble with the high-pressure per pound of steam generated per hour, and per unit of steam generator. installed capacity is shown in the accompanying table. The equipment described was placed in operation This tabulation does not include the switchhouse, screen late in 1937. Operation to date has shown that the house or the space, unoccupied at present, which has expected increase in plant economy due to this equip been provided for a future boiler. Although there has ment has been fully realized. been a substantial reduction in space occupied by tur bine-generators and turbine auxiliary equipment per unit of capacity, a considerable proportion of the reduc Program for A.S.M.E. St. Louis Meeting tion in total plant volume per kva of capacity has been due to the reduction in building space required per pound of steam generated. The summer meeting of the American Society of Me chanical Engineers will be held in St. Louis, June 19 to 23, inclusive. Informal conferences and committee meet ings will occupy Sunday and on Monday morning the COMPARISON OP BUILDING SPACE PER UNIT OF STEAM AND ELECTRIC GENERATING CAPACITV Plant Immedi- ately Preced 1930-1937 Original ing 1936-1937 Addition Installation Addition Only Steam generating ca pacity, lb per hr 3G0.000 560.000 300.000 Space occupied by steam generators and tbeir auxilia ries, cu ft 908,000 90S,000 269,000 Space occupied by steam generators and their auxilia ries in cu ft per lb of steam per hr 2.52 1.62 0.89 Capacity of main and auxiliarv gen erators (kva) 26.875 55,446 31,696 Space occupied by turbine-generators and tbeir auxilia ries, cu ft 632,000 1,187,000 239,000 Space occupied by turbine-generators aud their auxilia ries in cu ft psr kva 23.6 21.4 7.5 Total volume of mtuu power bouse (exclusive of space provided for future equipment), cu ft 1,540,000 2,095.000 50S.000 Total volume of main power house in cu ft per kva 57.4 37. S 10 0 Plant Includ ing 1936-1937 Addition 860,000 1.177,000 1.37 87,142 1,4 26,000 16* 4 2,603.000 29.9 first of two Fuels Sessions will be held. Papers at this session include: "A Down-Draft Conversion Burner for Domestic Furnaces," by J. R. Fellows; "Coal Carboniza tion and Its Relation to the Smoke Problem," by M. D. Curran; and "Smoke-Density Measurements," by H. E. Bumgardner. On Tuesday morning there will be a Boiler Feedwater Session at which the following papers will be presented: `Carbonaceous Zeolites--An Advance in Boiler-Feed water Conditioning," by Howard L. Tiger; "BoilerWater Treatment--New Methods for Preventing Em brittlement," by F. G. Straub and T. A. Bradbury; "Boiler Operation as It Affects Prime Movers," by S. E. Tray; and "The Behavior of Sodium Sulphite in HighPressure Boilers," by R. M. Hitchens and J. W. Purssell. A combined Hydraulic and Power Session is scheduled for Tuesday afternoon at which will be presented two papers, one on "Trends in Design of Large High-Pressure Boiler Units" by John Van Brunt, and the other "Operat ing Methods and Problems of a Combined Hydro- and Steam-Electric System" by H. Harrington and E. B. Conclusions Strowger. On Wednesday morning the second Fuels Session will The latest addition to Riverside Station shows that be held at which the following papers will be presented: superposition is not the only way of increasing the econ "Fuels for Industrial Heating Furnaces," by Matthew H. omy of an existing steam-electric- generating station. Mawhinney; "Power-Plant Requirements of a Dis The important features may be summarized as follows: tillery," by H. L. Walton; "Experiences and Difficulties 1. The new boiler and turbine-generator operating in Processing Coal," by L. C. McCabe. at 825 lb per sq in. S25 F steam conditions produce power A session on Welding and Flame-Cutting will comprise at the lowest total cost considering fuel cost, load fac papers on "Oxy-Acetylene Surface Hardening," by A. K. tor and investment charges in this particular case. Seernann; "Welding Applied to Plant Maintenance and 2. Steam may be extracted from the new turbine to Repairs," by H. R. Wass; and ".Arc-Welding Costs," bv the older 400-lb steam header, thus making the new H. W. P. Smith. RS-000239 1/17/02 NUECES