In Biomass Pyrolysis Plants, heat exchangers play a crucial role in various processes such as heating biomass to initiate pyrolysis, cooling of product gases, and heat recovery. Here are some types of heat exchangers commonly used in such plants, which may be designed according to standards like ASME Section VIII Div 1 & Div 2, TEMA, API 660, and analyzed using software like HTRI and PV Elite:

1. Shell and Tube Heat Exchangers:

   • U-tube Bundle: Often used for heating or cooling thermal oils or hot gases involved in the pyrolysis process.

   • Straight Tube Bundle: Suitable for applications where one fluid needs to be heated or cooled by another.

2. Plate Heat Exchangers:

   • Efficient for transferring heat between two fluids through a series of metal plates. They are compact and allow for high heat transfer rates.

3. Air-cooled Heat Exchangers (ACHE):

   • Used for cooling product gases after pyrolysis or other process gases in biomass plants where water availability might be limited.

4. Finned Tube Heat Exchangers:

   • Enhance heat transfer efficiency by increasing the surface area available for heat exchange, commonly used in gas cooling applications.

5. Shell and Coil Heat Exchangers:

   • Suitable for heating or cooling fluids in biomass pyrolysis processes, where compact design and efficient heat transfer are required.

6. Fluidized Bed Heat Exchangers:

   • Integrated into fluidized bed reactors to control and maintain temperatures required for biomass pyrolysis reactions.

These heat exchangers are designed and fabricated according to relevant industry standards such as ASME Section VIII Div 1 & Div 2 (for pressure vessels), TEMA (Tubular Exchanger Manufacturers Association), and API 660 (Shell-and-Tube Heat Exchangers for General Refinery Services). Thermal design and analysis are often performed using software like HTRI (Heat Transfer Research, Inc.) and PV Elite for mechanical design verification.

Each type of heat exchanger has specific advantages depending on factors such as the nature of fluids, operating pressures and temperatures, space constraints, and efficiency requirements in biomass pyrolysis plants.