Designing heat exchangers for Carbon Dioxide (CO2) plants involves several important considerations and standards. Here’s a breakdown based on the requirements you mentioned:

Standards and Codes

1. ASME Section VIII Div 1 & Div 2:

   • These are the American Society of Mechanical Engineers codes for pressure vessel design. They provide rules for the construction of pressure vessels and heat exchangers, ensuring safety and reliability.

2. TEMA (Tubular Exchanger Manufacturers Association):

   • TEMA standards provide guidelines for the design, fabrication, and construction of shell-and-tube heat exchangers, which are commonly used in industrial applications including CO2 plants.

3. API 660:

   • This standard specifically covers shell-and-tube heat exchangers for the petroleum, petrochemical, and natural gas industries. It provides additional guidelines and requirements for design, materials, fabrication, inspection, testing, and shipping.

Design Considerations

1. Thermal Design (HTRI Thermal Design):

   • HTRI (Heat Transfer Research, Inc.) software and methodologies are widely used for thermal design of heat exchangers. This involves calculating heat transfer coefficients, determining surface areas, and optimizing the design for efficient heat transfer.

2. Mechanical Design (PVElite):

   • PVElite is a software tool used for mechanical design of pressure vessels and heat exchangers according to ASME standards. It ensures that the design meets structural integrity requirements under specified operating conditions.

3. Heat Balance:

   • This involves determining the heat duties (heat loads) of the heat exchangers within the CO2 plant. It considers both the heating and cooling requirements of different process streams and ensures that the selected heat exchangers can handle these duties effectively.

4. Mass Balance:

   • Mass balance calculations are crucial for understanding the flow rates and compositions of different process streams within the CO2 plant. This information is essential for sizing the heat exchangers correctly and ensuring they can handle the anticipated process conditions.

5. P&ID (Piping and Instrumentation Diagram):

   • P&IDs are essential for understanding the process flow and the locations where heat exchangers are required. They provide details on process conditions (temperatures, pressures, flow rates) that influence the heat exchanger design.

Design Process

• Initial Sizing: Determine the preliminary size and type (shell-and-tube, plate heat exchanger, etc.) of heat exchangers based on process requirements and operating conditions.

• Detailed Design: Use thermal design software (like HTRI) for calculating heat transfer coefficients, surface areas, and pressure drops. Validate mechanical design using PVElite to ensure compliance with ASME standards.

• Material Selection: Choose materials based on compatibility with CO2 and other process fluids, as well as considerations like corrosion resistance and thermal conductivity.

• Fabrication and Testing: Ensure that fabrication and testing procedures adhere to applicable standards (ASME, API) to guarantee the quality and safety of the heat exchangers.

• Installation and Commissioning: Coordinate with other disciplines (process engineering, piping, instrumentation) for proper installation and integration of the heat exchangers into the CO2 plant.

By following these guidelines and standards, you can design heat exchangers that are safe, efficient, and reliable for use in CO2 plants, meeting both thermal performance and mechanical integrity requirements.