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• 11. [Image] A Geological and Geophysical Study of the Geothermal Energy Potential of Pilgrim Springs, Alaska

  	The Pilgrim Springs geothermal area, located about 75 km north of Nome, was the subject of an intensive, reconnaissance-level geophysical and geological study during a 90-day period in the summer of 1979. ...
  	Citation × Citation Citation Abstract Copy Title: A Geological and Geophysical Study of the Geothermal Energy Potential of Pilgrim Springs, Alaska Author: Turner, Donald L. [ed.] Year: 1980 The Pilgrim Springs geothermal area, located about 75 km north of Nome, was the subject of an intensive, reconnaissance-level geophysical and geological study during a 90-day period in the summer of 1979. The thermal springs are located in a northeast-oriented, oval area of thawed ground approximately 1.5 km{sup 2} in size, bordered on the north by the Pilgrim River. A second, much smaller, thermal anomaly was discovered about 3 km northeast of the main thawed area. Continuous permafrost in the surrounding region is on the order of 100 m thick. Present surface thermal spring discharge is {approx} 4.2 x 10{sup -3} m{sup 3} s{sup -1} (67 gallons/minute) of alkali-chloride-type water at a temperature of 81 C. The reason for its high salinity is not yet understood because of conflicting evidence for seawater vs. other possible water sources. Preliminary Na-K-Ca geothermometry suggests deep reservoir temperatures approaching 150 C, but interpretation of these results is difficult because of their dependence on an unknown water mixing history. Based on these estimates, and present surface and drill hole water temperatures, Pilgrim Springs would be classified as an intermediate-temperature, liquid-dominated geothermal system; UAG-R-271 Title: A Geological and Geophysical Study of the Geothermal Energy Potential of Pilgrim Springs, Alaska Author: Turner, Donald L. [ed.] Year: 1980 The Pilgrim Springs geothermal area, located about 75 km north of Nome, was the subject of an intensive, reconnaissance-level geophysical and geological study during a 90-day period in the summer of 1979. The thermal springs are located in a northeast-oriented, oval area of thawed ground approximately 1.5 km{sup 2} in size, bordered on the north by the Pilgrim River. A second, much smaller, thermal anomaly was discovered about 3 km northeast of the main thawed area. Continuous permafrost in the surrounding region is on the order of 100 m thick. Present surface thermal spring discharge is {approx} 4.2 x 10{sup -3} m{sup 3} s{sup -1} (67 gallons/minute) of alkali-chloride-type water at a temperature of 81 C. The reason for its high salinity is not yet understood because of conflicting evidence for seawater vs. other possible water sources. Preliminary Na-K-Ca geothermometry suggests deep reservoir temperatures approaching 150 C, but interpretation of these results is difficult because of their dependence on an unknown water mixing history. Based on these estimates, and present surface and drill hole water temperatures, Pilgrim Springs would be classified as an intermediate-temperature, liquid-dominated geothermal system; UAG-R-271 Close

• 12. [Image] Geothermal exploration assessment and interpretation, Upper Klamath Lake Area, Klamath Basin, Oregon

  	Data from public and private sources on the Klamath Basin geothermal resource are reviewed, synthesized, and reinterpreted. In this, the second and final phase of the work, geological, remote sensing, ...
  	Citation × Citation Citation Abstract Copy Title: Geothermal exploration assessment and interpretation, Upper Klamath Lake Area, Klamath Basin, Oregon Author: Stark, M. Year: 1980 Data from public and private sources on the Klamath Basin geothermal resource are reviewed, synthesized, and reinterpreted. In this, the second and final phase of the work, geological, remote sensing, geochemical, temperature gradient, gravity, aeromagnetic, and electrical resistivity data sets are examined. These data were derived from surveys concentrated on the east and west shores of Upper Klamath Lake. The geological, remote sensing, and potential field data suggest a few northeast-trending discontinuities, which cross the regional north-westerly strike. The near-surface distribution of warm water appears to be related to the intersections of these lineaments and northwest-trending faults. The groundwater geochemical data are reviewed and the various reservoir temperature estimates compared. Particular attention is given to specific electrical conductivities of waters as an interpretational aid to the subsurface resistivity results. A clear trend emerges in the Klamath Falls/Olene Gap area; hotter waters are associated with higher specific conductivities. In the Nuss Lake/Stukel Mountain area the opposite trend prevails, although the relationship is somewhat equivocal; LBL-10140 Title: Geothermal exploration assessment and interpretation, Upper Klamath Lake Area, Klamath Basin, Oregon Author: Stark, M. Year: 1980 Data from public and private sources on the Klamath Basin geothermal resource are reviewed, synthesized, and reinterpreted. In this, the second and final phase of the work, geological, remote sensing, geochemical, temperature gradient, gravity, aeromagnetic, and electrical resistivity data sets are examined. These data were derived from surveys concentrated on the east and west shores of Upper Klamath Lake. The geological, remote sensing, and potential field data suggest a few northeast-trending discontinuities, which cross the regional north-westerly strike. The near-surface distribution of warm water appears to be related to the intersections of these lineaments and northwest-trending faults. The groundwater geochemical data are reviewed and the various reservoir temperature estimates compared. Particular attention is given to specific electrical conductivities of waters as an interpretational aid to the subsurface resistivity results. A clear trend emerges in the Klamath Falls/Olene Gap area; hotter waters are associated with higher specific conductivities. In the Nuss Lake/Stukel Mountain area the opposite trend prevails, although the relationship is somewhat equivocal; LBL-10140 Close

• 13. [Image] Geothermal direct heat project, Marlin, Texas: Environmental assessment

  	The Federal action addressed is retrofitting a heating and hot water system in a hospital at Marlin, Texas, with a geothermal preheat system. The project will be located within the existing hospital boiler ...
  	Citation × Citation Citation Abstract Copy Title: Geothermal direct heat project, Marlin, Texas: Environmental assessment Year: 1979 The Federal action addressed is retrofitting a heating and hot water system in a hospital at Marlin, Texas, with a geothermal preheat system. The project will be located within the existing hospital boiler room. One supply well will be drilled in an existing adjacent parking lot. Fluid disposal from operation will depend on fluid properties and may be by surface disposal to existing street drains, by surface disposal to a new drainage system, or by injection into a new injection well, depending on total dissolved solids (TDS) content. Environmental impacts of construction are expected to be small because of the existing structures and paved areas. Construction run-off and geothermal flow-test fluid will pass through a small pond in the city park, lowering its water quality, at least temporarily. Construction noise is not expected to be out of character with existing noises around the hospital. Project operation is not expected to produce significant impacts because of the decision point to determine fluid composition prior to designating a disposal method. Injection would be into a saline aquifer, and surface discharge would not appreciably lower water quality in the Brazos River; DOE/EA-0067 Title: Geothermal direct heat project, Marlin, Texas: Environmental assessment Year: 1979 The Federal action addressed is retrofitting a heating and hot water system in a hospital at Marlin, Texas, with a geothermal preheat system. The project will be located within the existing hospital boiler room. One supply well will be drilled in an existing adjacent parking lot. Fluid disposal from operation will depend on fluid properties and may be by surface disposal to existing street drains, by surface disposal to a new drainage system, or by injection into a new injection well, depending on total dissolved solids (TDS) content. Environmental impacts of construction are expected to be small because of the existing structures and paved areas. Construction run-off and geothermal flow-test fluid will pass through a small pond in the city park, lowering its water quality, at least temporarily. Construction noise is not expected to be out of character with existing noises around the hospital. Project operation is not expected to produce significant impacts because of the decision point to determine fluid composition prior to designating a disposal method. Injection would be into a saline aquifer, and surface discharge would not appreciably lower water quality in the Brazos River; DOE/EA-0067 Close

• 14. [Image] Downhole Heat Exchanger for Shallow Geothermal Systems: Performance, Economics and Applicability

  	Heat exchangers located within the wellbore of shallow geothermal resources are presently being used at several locations in the U.S. These heat exchangers are referred to as downhole heat exchangers. ...
  	Citation × Citation Citation Abstract Copy Title: Downhole Heat Exchanger for Shallow Geothermal Systems: Performance, Economics and Applicability Author: Reistad, G. M. Heat exchangers located within the wellbore of shallow geothermal resources are presently being used at several locations in the U.S. These heat exchangers are referred to as downhole heat exchangers. Such installations can have thermal energy output capacities as high as 1 MW for space heating with source water temperature of 90 to 100°C. This work reports on the performance and economics of downhole heat exchangers relative to the alternative geothermal system which pumps the fluid out of the ground and uses heat exchangers located at the earth's surface. Results indicate that the downhole heat exchange systems for capacity requirements less than about 500 to 100 kW are in general more desirable than the surface heat exchange systems for low capacity (less than about 500 to 1000 kW) requirements and shallow geothermal resources. For higher capacities the surface heat exchange systems become more economical. Furthermore, for large depths, the high capacities available from the surface systems are required in order to make the geothermal energy competitive with other sources Title: Downhole Heat Exchanger for Shallow Geothermal Systems: Performance, Economics and Applicability Author: Reistad, G. M. Heat exchangers located within the wellbore of shallow geothermal resources are presently being used at several locations in the U.S. These heat exchangers are referred to as downhole heat exchangers. Such installations can have thermal energy output capacities as high as 1 MW for space heating with source water temperature of 90 to 100°C. This work reports on the performance and economics of downhole heat exchangers relative to the alternative geothermal system which pumps the fluid out of the ground and uses heat exchangers located at the earth's surface. Results indicate that the downhole heat exchange systems for capacity requirements less than about 500 to 100 kW are in general more desirable than the surface heat exchange systems for low capacity (less than about 500 to 1000 kW) requirements and shallow geothermal resources. For higher capacities the surface heat exchange systems become more economical. Furthermore, for large depths, the high capacities available from the surface systems are required in order to make the geothermal energy competitive with other sources Close

• 15. [Image] Industry Participation in DOE-Sponsored Geopressured Geothermal Resource Development

  	The Salt Water Disposal Study reviewed subsurface salt water disposal experience on the Texas and Louisiana Gulf Coast. This preliminary study concluded that subsurface brine disposal should be possible ...
  	Citation × Citation Citation Abstract Copy Title: Industry Participation in DOE-Sponsored Geopressured Geothermal Resource Development Author: Coffer, H. F Year: 1979 The Salt Water Disposal Study reviewed subsurface salt water disposal experience on the Texas and Louisiana Gulf Coast. This preliminary study concluded that subsurface brine disposal should be possible in the areas of interest with adequate evaluation of the geology of each area and a well designed and constructed surface and subsurface facility. The industry survey indicated general satisfactory with the technical design of the resource evaluation program but felt the program should be moving faster. Excellent communication with industry had been maintained through the forum meetings and the status reports Title: Industry Participation in DOE-Sponsored Geopressured Geothermal Resource Development Author: Coffer, H. F Year: 1979 The Salt Water Disposal Study reviewed subsurface salt water disposal experience on the Texas and Louisiana Gulf Coast. This preliminary study concluded that subsurface brine disposal should be possible in the areas of interest with adequate evaluation of the geology of each area and a well designed and constructed surface and subsurface facility. The industry survey indicated general satisfactory with the technical design of the resource evaluation program but felt the program should be moving faster. Excellent communication with industry had been maintained through the forum meetings and the status reports Close

• 16. [Image] Sweet Lake Geopressured-Geothermal Project, Magma Gulf-Technadril/DOE Amoco FEE Volume II: Surface Installations Reservoir Testing; Annual Report for the Period February 28, 1981-February 10, 1982

  	The Magma Gulf-Technadril/Department of Energy Amoco Fee # 1 (production) and salt water disposal wells were drilled in the period from August, 1980 to February 1981. Surface facilities were designed and ...
  	Citation × Citation Citation Abstract Copy Title: Sweet Lake Geopressured-Geothermal Project, Magma Gulf-Technadril/DOE Amoco FEE Volume II: Surface Installations Reservoir Testing; Annual Report for the Period February 28, 1981-February 10, 1982 Author: Hoffman, K. S. (ed.) Year: 1982 The Magma Gulf-Technadril/Department of Energy Amoco Fee # 1 (production) and salt water disposal wells were drilled in the period from August, 1980 to February 1981. Surface facilities were designed and constructed during March-June 1981. Flow testing began in June 1981 and continued until February, 1982 Title: Sweet Lake Geopressured-Geothermal Project, Magma Gulf-Technadril/DOE Amoco FEE Volume II: Surface Installations Reservoir Testing; Annual Report for the Period February 28, 1981-February 10, 1982 Author: Hoffman, K. S. (ed.) Year: 1982 The Magma Gulf-Technadril/Department of Energy Amoco Fee # 1 (production) and salt water disposal wells were drilled in the period from August, 1980 to February 1981. Surface facilities were designed and constructed during March-June 1981. Flow testing began in June 1981 and continued until February, 1982 Close

• 17. [Image] Environmental Monitoring for the Hot Dry Rock Geothermal Energy Development Project, Annual Report for the Period July 1975-June 1976

  	For the last four years, the Los Alamos Scientific Laboratory has been investigating the feasibility demonstration of a technique for extracting geothermal energy from hot dry rock existing at moderate ...
  	Citation × Citation Citation Abstract Copy Title: Environmental Monitoring for the Hot Dry Rock Geothermal Energy Development Project, Annual Report for the Period July 1975-June 1976 Author: Pettitt, Roland A. Year: 1976 For the last four years, the Los Alamos Scientific Laboratory has been investigating the feasibility demonstration of a technique for extracting geothermal energy from hot dry rock existing at moderate depths beneath the surface of the earth. In the hot dry rock (HDR) concept, a manmade geothermal reservoir would be formed by drilling an initial borehole into a region of hot rock, creating a large fracture at the bottom of the hole, then intersecting the fractured area with a second borehole. The heat contained in this underground reservoir would then be brought to the surface by the circulation of water through the system. The objectives of this environmental monitoring report are to provide a brief conceptual and historical summary of the Hot Dry Rock Geothermal Project, a brief overview of the environmental monitoring responsibilities and activities of the Los Alamos Scientific Laboratory, and descriptions of the studies, problems, and results obtained from the various monitoring programs. Included are descriptions of the work that has been done in three major monitoring areas: (1) water quality, both surface and subsurface; (2) seismicity, with a discussion of the monitoring strategy of regional, local, and close-in detection networks; and (3) climatology. The purpose of these programs is to record baseline data, define potential effects from the project activities, and determine and record any impacts that may occur. The development of the hot dry rock geothermal energy resource and associated energy extraction technology is a new field of endeavor, with no established environmental guidelines. It is doubtful if the problems encountered and solutions devised in traditional geothermal systems will apply directly to hot dry rock development. Therefore, the impacts that are encountered in this project will be of particular value in making future environmental Assessments for this type of energy resource development in other locations in different geologic settings. By the end of the reporting period, there had been no unacceptable impacts on the environment in any of the three monitoring areas Title: Environmental Monitoring for the Hot Dry Rock Geothermal Energy Development Project, Annual Report for the Period July 1975-June 1976 Author: Pettitt, Roland A. Year: 1976 For the last four years, the Los Alamos Scientific Laboratory has been investigating the feasibility demonstration of a technique for extracting geothermal energy from hot dry rock existing at moderate depths beneath the surface of the earth. In the hot dry rock (HDR) concept, a manmade geothermal reservoir would be formed by drilling an initial borehole into a region of hot rock, creating a large fracture at the bottom of the hole, then intersecting the fractured area with a second borehole. The heat contained in this underground reservoir would then be brought to the surface by the circulation of water through the system. The objectives of this environmental monitoring report are to provide a brief conceptual and historical summary of the Hot Dry Rock Geothermal Project, a brief overview of the environmental monitoring responsibilities and activities of the Los Alamos Scientific Laboratory, and descriptions of the studies, problems, and results obtained from the various monitoring programs. Included are descriptions of the work that has been done in three major monitoring areas: (1) water quality, both surface and subsurface; (2) seismicity, with a discussion of the monitoring strategy of regional, local, and close-in detection networks; and (3) climatology. The purpose of these programs is to record baseline data, define potential effects from the project activities, and determine and record any impacts that may occur. The development of the hot dry rock geothermal energy resource and associated energy extraction technology is a new field of endeavor, with no established environmental guidelines. It is doubtful if the problems encountered and solutions devised in traditional geothermal systems will apply directly to hot dry rock development. Therefore, the impacts that are encountered in this project will be of particular value in making future environmental Assessments for this type of energy resource development in other locations in different geologic settings. By the end of the reporting period, there had been no unacceptable impacts on the environment in any of the three monitoring areas Close

• 18. [Image] Low-Temperature Geothermal Potential of the Ojo Caliente Warm Springs Area, Northern New Mexico

  	A detailed geochemical investigation of 17 waters (thermal and cold, mineralized and dilute) was performed in the Ojo Caliente-La Madera area. Two types of thermomineral waters have separate and distinctive ...
  	Citation × Citation Citation Abstract Copy Title: Low-Temperature Geothermal Potential of the Ojo Caliente Warm Springs Area, Northern New Mexico Author: Vuataz, F.D. Year: 1984 A detailed geochemical investigation of 17 waters (thermal and cold, mineralized and dilute) was performed in the Ojo Caliente-La Madera area. Two types of thermomineral waters have separate and distinctive geologic, geochemical, and geothermal characteristics. The water from Ojo Caliente Resort emerges with temperatures less than or equal to 54/sup 0/C from a Precambrian metarhyolite. Its chemistry, typically Na-HCO/sub 3/, has a total mineralization of 3600 mg/l. Isotopic studies have shown that the thermal water emerges from the springs and a hot well without significant mixing with the cold shallow aquifer of the valley alluvium. However, the cold aquifer adjacent to the resort does contain varying amounts of thermal water that originates from the warm spring system. Geothermometry calculations indicate that the thermal water may be as hot as 85/sup 0/C at depth before its ascent toward surface. Thermodynamic computations on the reaction states of numerous mineral phases suggest that the thermal water will not cause major scaling problems if the hot water is utilized for direct-use geothermal applications. By means of a network of very shallow holes, temperature and electrical conductivity anomalies have been found elsewhere in the valley around Ojo Caliente, and resistivity soundings have confirmed the presence of a plume of thermal water entering the shallow aquifer. The group of lukewarm springs around La Madera, with temperatures less than or equal to 29/sup 0/C, chemical type of NaCaMg-HCO/sub 3/Cl and with a total mineralization less than or equal to 1500 mg/l behaves as a different system without any Apparent relation to the Ojo Caliente system. Its temperature at depth is not believed to exceed 35 to 40/sup 0/C Title: Low-Temperature Geothermal Potential of the Ojo Caliente Warm Springs Area, Northern New Mexico Author: Vuataz, F.D. Year: 1984 A detailed geochemical investigation of 17 waters (thermal and cold, mineralized and dilute) was performed in the Ojo Caliente-La Madera area. Two types of thermomineral waters have separate and distinctive geologic, geochemical, and geothermal characteristics. The water from Ojo Caliente Resort emerges with temperatures less than or equal to 54/sup 0/C from a Precambrian metarhyolite. Its chemistry, typically Na-HCO/sub 3/, has a total mineralization of 3600 mg/l. Isotopic studies have shown that the thermal water emerges from the springs and a hot well without significant mixing with the cold shallow aquifer of the valley alluvium. However, the cold aquifer adjacent to the resort does contain varying amounts of thermal water that originates from the warm spring system. Geothermometry calculations indicate that the thermal water may be as hot as 85/sup 0/C at depth before its ascent toward surface. Thermodynamic computations on the reaction states of numerous mineral phases suggest that the thermal water will not cause major scaling problems if the hot water is utilized for direct-use geothermal applications. By means of a network of very shallow holes, temperature and electrical conductivity anomalies have been found elsewhere in the valley around Ojo Caliente, and resistivity soundings have confirmed the presence of a plume of thermal water entering the shallow aquifer. The group of lukewarm springs around La Madera, with temperatures less than or equal to 29/sup 0/C, chemical type of NaCaMg-HCO/sub 3/Cl and with a total mineralization less than or equal to 1500 mg/l behaves as a different system without any Apparent relation to the Ojo Caliente system. Its temperature at depth is not believed to exceed 35 to 40/sup 0/C Close

• 19. [Image] DHE (Downhole Heat Exchangers)

  	The use of downhole heat exchangers (DHE) for residential or commercial space and domestic water heating and other applications has several desirable features. Systems are nearly or completely passive ...
  	Citation × Citation Citation Abstract Copy Title: DHE (Downhole Heat Exchangers) Author: Culver, G. Year: 1990 The use of downhole heat exchangers (DHE) for residential or commercial space and domestic water heating and other applications has several desirable features. Systems are nearly or completely passive -- that is, no or very little geothermal water or steam is produced from the well either reducing or completely eliminating surface environmental concerns and the need for disposal systems or injection wells. Initial cost of pumps and installation are eliminated or reduced along with pumping power costs and maintenance costs associated with pumping often corrosive geothermal fluids. Many residential and small commercial systems do not require circulating pumps because the density difference in the incoming and outgoing sides of the loop are sufficient to overcome circulating friction losses in the entire system. The major disadvantage of DHEs is their dependence on natural heat flow. In areas where geological conditions provide high permeability and a natural hydraulic gradient, DHEs can provide a substantial quantity of heat. A single 500-ft (152 m) well in Klamath Falls, Oregon, supplies over one megawatt thermal and output is apparently limited by the surface area of pipe that can be installed in the well bore. In contrast, DHEs used in conjunction with heat pumps may supply less than 8 KW from a well of similar depth. Here output is limited by conductive heat flow with perhaps a small contribution from convection near the well bore. The highest capacity DHE reported to date, in Turkey, supplies 6 MW thermal from an 820-ft (250 m) well. There were two main goals for this project. The first was to gather, disseminate and exchange internationally information on DHEs. The second was to perform experiments that would provide insight into well bore/aquifer interaction and thereby provide more information on which to base DHE designs. 27 refs., 31 figs., 3 tabs. Title: DHE (Downhole Heat Exchangers) Author: Culver, G. Year: 1990 The use of downhole heat exchangers (DHE) for residential or commercial space and domestic water heating and other applications has several desirable features. Systems are nearly or completely passive -- that is, no or very little geothermal water or steam is produced from the well either reducing or completely eliminating surface environmental concerns and the need for disposal systems or injection wells. Initial cost of pumps and installation are eliminated or reduced along with pumping power costs and maintenance costs associated with pumping often corrosive geothermal fluids. Many residential and small commercial systems do not require circulating pumps because the density difference in the incoming and outgoing sides of the loop are sufficient to overcome circulating friction losses in the entire system. The major disadvantage of DHEs is their dependence on natural heat flow. In areas where geological conditions provide high permeability and a natural hydraulic gradient, DHEs can provide a substantial quantity of heat. A single 500-ft (152 m) well in Klamath Falls, Oregon, supplies over one megawatt thermal and output is apparently limited by the surface area of pipe that can be installed in the well bore. In contrast, DHEs used in conjunction with heat pumps may supply less than 8 KW from a well of similar depth. Here output is limited by conductive heat flow with perhaps a small contribution from convection near the well bore. The highest capacity DHE reported to date, in Turkey, supplies 6 MW thermal from an 820-ft (250 m) well. There were two main goals for this project. The first was to gather, disseminate and exchange internationally information on DHEs. The second was to perform experiments that would provide insight into well bore/aquifer interaction and thereby provide more information on which to base DHE designs. 27 refs., 31 figs., 3 tabs. Close

• 20. [Image] Liquid-Fluidized-Bed Heat Exchanger Design Parameters

  	Liquid-fluidized-bed heat exchangers prevent scale accumulation on heat transfer surfaces and reduce the required heat transfer surface when scaling fluids, such as geothermal water, are used as the primary ...
  	Citation × Citation Citation Abstract Copy Title: Liquid-Fluidized-Bed Heat Exchanger Design Parameters Author: Allen, C.A. Year: 1978 Liquid-fluidized-bed heat exchangers prevent scale accumulation on heat transfer surfaces and reduce the required heat transfer surface when scaling fluids, such as geothermal water, are used as the primary or working fluid. Liquid-fluidized-bed heat exchangers, principles of operation, and design parameters are described. Horizontal and vertical assemblies are discussed, including problems encountered with both designs. Bed-side heat transfer coefficients are given for limited cases, and a correlation is provided for calculating heat transfer coefficients for horizontal assemblies. A design example for a 60 kW/sub (e)/ (60 kW/sub (electric)/ preheater is included Title: Liquid-Fluidized-Bed Heat Exchanger Design Parameters Author: Allen, C.A. Year: 1978 Liquid-fluidized-bed heat exchangers prevent scale accumulation on heat transfer surfaces and reduce the required heat transfer surface when scaling fluids, such as geothermal water, are used as the primary or working fluid. Liquid-fluidized-bed heat exchangers, principles of operation, and design parameters are described. Horizontal and vertical assemblies are discussed, including problems encountered with both designs. Bed-side heat transfer coefficients are given for limited cases, and a correlation is provided for calculating heat transfer coefficients for horizontal assemblies. A design example for a 60 kW/sub (e)/ (60 kW/sub (electric)/ preheater is included Close