Flooded Heat Exchangers
Hot Water Generation
Steam heat transfer equipment emerged in the 20th century with space-saving GREEN design by Advanced Steam Technology. The Advanced Steam Technology XE Thermal unit is a patented vertical steam-to-water exchanger for building heat. This compact, modern design replaces bulky, outdated steam heaters. Research and testing have eliminated flash steam, making these units suitable for LEED certifications while saving energy and money. Size is a key consideration, especially for retrofit applications. Large exchangers from 40–50 years ago are now failing, often surrounded by built-up facilities. Replacing them typically requires extensive demolition. In contrast, vertical units fit through standard doorways, minimize downtime, and can be installed alongside existing systems. Old units may be encapsulated or cut into pieces for removal.
Flooded Heat Exchangers
Hot Water Generation
Steam heat transfer equipment emerged in the 20th century with space-saving GREEN design by Advanced Steam Technology. The Advanced Steam Technology XE Thermal unit is a patented vertical steam-to-water exchanger for building heat. This compact, modern design replaces bulky, outdated steam heaters. Research and testing have eliminated flash steam, making these units suitable for LEED certifications while saving energy and money. Size is a key consideration, especially for retrofit applications. Large exchangers from 40–50 years ago are now failing, often surrounded by built-up facilities. Replacing them typically requires extensive demolition. In contrast, vertical units fit through standard doorways, minimize downtime, and can be installed alongside existing systems. Old units may be encapsulated or cut into pieces for removal.
STEAM FUNDAMENTALS
When make-up water enters the boiler room or power plant, its first stop after treatment is the deaerator. It is sprayed over heated trays to drive out dissolved gases. The water is usually heated (40°F to 205°F) by adding sensible heat. It takes about 1 BTU to raise a pound (or pint) of water by 1F. These BTU’s are supplied by steam in the trays.
PRESSURE TO HEAT
A sophisticated system for a university, food processor, or chemical plant will generate steam at 600 psig or higher, because steam is used to generate power before distribution. The steam is normally distributed at 100 or 150 psig. Some industrial plants (usually with turbine drives) will distribute steam up to 600 psig. Systems are designed around higher pressure distribution because of the steam volume.
| PRESSURE | TEMPERATURE | VOLUME |
|---|---|---|
| 0 psig | 212°F | 27 ft3 |
| 15 psig | 250°F | 14 ft3 |
| 60 psig | 308°F | 6 ft3 |
| 100 psig | 338°F | 4 ft3 |
| 150 psig | 366°F | 3 ft3 |
| 600 psig | 486°F | 1 ft3 |
| PRESSURE | TEMPERATURE | SENSIBLE HEAT | LATENT HEAT |
|---|---|---|---|
| 0 psig | 212°F | 180 Btu | 970 Btu |
| 15 psig | 250°F | 218 Btu | 945 Btu |
| 60 psig | 308°F | 277 Btu | 905 Btu |
| 100 psig | 338°F | 308 Btu | 880 Btu |
| 150 psig | 366°F | 338 Btu | 857 Btu |
| 600 psig | 486°F | 472 Btu | 732 Btu |
PRESSURE TO VOLUME
High-pressure steam minimizes pipe sizes and pressure drops. Intermediate-pressure steam (60-80 psig) is used for sterilizers, autoclaves, mixers, and pumps. Pressure reducing stations generate intermediate-pressure steam. Low-pressure steam (10-15 psig) heats air and water. Domestic water heats sinks and showers, while service water circulates through coils or baseboards to heat air. Facilities typically use at least 50% of their steam for heating water.
STEAM FUNDAMENTALS
When make-up water enters the boiler room or power plant, its first stop after treatment is the deaerator. It is sprayed over heated trays to drive out dissolved gases. The water is usually heated (40°F to 205°F) by adding sensible heat. It takes about 1 BTU to raise a pound (or pint) of water by 1F. These BTU’s are supplied by steam in the trays.
| PRESSURE | TEMPERATURE | VOLUME |
|---|---|---|
| 0 psig | 212°F | 27 ft3 |
| 15 psig | 250°F | 14 ft3 |
| 60 psig | 308°F | 6 ft3 |
| 100 psig | 338°F | 4 ft3 |
| 150 psig | 366°F | 3 ft3 |
| 600 psig | 486°F | 1 ft3 |
PRESSURE TO HEAT
A sophisticated system for a university, food processor, or chemical plant will generate steam at 600 psig or higher, because steam is used to generate power before distribution. The steam is normally distributed at 100 or 150 psig. Some industrial plants (usually with turbine drives) will distribute steam up to 600 psig. Systems are designed around higher pressure distribution because of the steam volume.
| PRESSURE | TEMPERATURE | SENSIBLE HEAT | LATENT HEAT |
|---|---|---|---|
| 0 psig | 212°F | 180 Btu | 970 Btu |
| 15 psig | 250°F | 218 Btu | 945 Btu |
| 60 psig | 308°F | 277 Btu | 905 Btu |
| 100 psig | 338°F | 308 Btu | 880 Btu |
| 150 psig | 366°F | 338 Btu | 857 Btu |
| 600 psig | 486°F | 472 Btu | 732 Btu |
PRESSURE TO VOLUME
High-pressure steam minimizes pipe sizes and pressure drops. Intermediate-pressure steam (60-80 psig) is used for sterilizers, autoclaves, mixers, and pumps. Pressure reducing stations generate intermediate-pressure steam. Low-pressure steam (10-15 psig) heats air and water. Domestic water heats sinks and showers, while service water circulates through coils or baseboards to heat air. Facilities typically use at least 50% of their steam for heating water.
Technical Information
Conventional Heaters
Heating air or water often uses a modulating valve to adjust steam pressure based on temperature feedback. While effective for storage tanks, “feedback” control reacts only after temperature changes, potentially allowing overheated water into the system.
A common issue is vacuum formation, which prevents the heat exchanger from draining, causing water hammer and uneven control. Installing a vacuum breaker solves this by allowing air in to break the vacuum and enable drainage. However, this adds complexity due to air in the exchanger, low pressure, and the need for a pump with overhead return lines. Between larger steam trap selection, air vent placement, and adding a condensate pump, the design gets expensive.
Lifting condensate to an overhead return is not recommended, so a condensate pump may be needed and thermal “U loops” are needed.
ADVANCED STEAM TECHNOLOGY XE Thermal
