Heat Exchange Institute, Inc.
The Heat Exchange Institute (HEI) is a non-profit trade association committed to the technical advancement, promotion, and understanding of a broad range of utility and industrial-scale heat exchange and vacuum apparatus.
HEI members concentrate their efforts on the manufacturing and engineering aspects of air cooled condensers, steam surface condensers, closed feedwater heaters, shell and tube heat exchangers, plate heat exchangers, liquid ring vacuum pumps, steam jet ejectors and deaerators.
The primary purpose of HEI is to develop and publish standards which advance the technology, increase the efficiency, and promote the use of heat exchange and vacuum apparatus.
This objective is accomplished through technology-specific committees operating under the authority of the Institute’s seven Sections:
Each of these sections sponsors a technical committee which is charged with developing and revising standards specific to its range of products.
Each technical committee meets at least twice a year, with each section member designating an engineer as its representative on the Technical Committee; ongoing communication among committee members assures that the standards are based on the latest available technology.
Since its founding over 79 years ago, the Institute has earned international recognition as the leading authority on the technologies for heat exchange and vacuum apparatus. Institute standards are used throughout the world for the design, manufacture and operation of heat exchange and vacuum equipment.
HEI has expanded its efforts to share the latest technology by sponsoring workshops and publishing articles for users of heat exchange and vacuum equipment.
Key Heat Exchange Equipment
Heat Exchangers
Heat exchangers are the core components used in heat exchange systems. They work on the principle of thermal conduction and convective heat transfer to move heat from one fluid to another. The two most common types are:
- Shell-and-tube heat exchangers: Common in industries where high pressure and temperature differences exist, such as in power plants and refineries.
- Plate heat exchangers: Made up of multiple thin plates stacked together, these are often used in industries where space is limited and efficiency is paramount, like in HVAC systems or food processing.
Deaerators
A deaerator is a crucial component in steam generation systems, especially in power plants, petrochemical plants, and refineries. Its purpose is to remove dissolved gases, primarily oxygen and carbon dioxide, from feedwater before it enters the boiler. This is critical because dissolved gases can cause corrosion in the boiler and associated equipment. Deaerators are typically used in steam cycles to ensure the water entering the steam boiler is free from gases that could cause scaling, corrosion, and other operational issues.
Steam Surface Condensers
A steam surface condenser is used in power plants and other systems that utilize steam turbines. It serves as the component that cools and condenses the exhaust steam from a steam turbine back into liquid water, which can be reused in the system. This process is crucial for maintaining the efficiency of steam cycles.
- Functionality: In a surface condenser, steam from the turbine passes over a series of tubes through which cooling water flows. As the steam comes in contact with the cooler tubes, it condenses back into water. The condensed water (or condensate) is then returned to the boiler for reuse.
- Efficiency considerations: Surface condensers are typically designed to operate with minimal cooling water temperature rise, maximizing heat transfer efficiency.
Air Cooled Heat Exchangers
These are used in applications where water availability is limited or not preferred. Instead of water, ambient air is used to cool the fluid inside the heat exchanger. These systems typically feature finned tubes and large fans to enhance heat transfer between the fluid and the air.
- Applications: Common in areas with water scarcity or where water treatment is expensive or challenging (e.g., offshore platforms, desert environments).