Plate heat exchanger vs Shell and tube heat exchanger
| Feature | Plate Heat Exchanger (PHE) | Shell and Tube Heat Exchanger (STHE) |
| Compactness & Space | Very compact. High surface area to volume ratio. Saves significant space. | Bulky and large. Requires more floor space and headroom. |
| Heat Transfer Efficiency | Very high. Turbulent flow at low Reynolds numbers ensures high heat transfer coefficients. | Moderate. Flow is often laminar or transitional in the shell side, leading to lower coefficients. |
| Cost | Lower initial cost for standard materials (stainless steel) and duties. | Higher initial cost due to more material and fabrication labor. |
| Flexibility & Maintenance | High. Capacity can be easily increased by adding plates. Easy to open and clean. | Low. Fixed capacity. Maintenance is more complex and time-consuming (often requires tube bundle pulling). |
| Pressure & Temperature | Limited. Typically up to 25 bar and 150-200°C (gasket limitation). Brazed versions can go higher. | Very High. Can be designed for extreme pressures (100s of bar) and temperatures (1000°C+). |
| Plate heat exchanger vs Shell and tube heat exchanger Feature Plate Heat Exchanger (PHE) Shell and Tube Heat Exchanger (STHE) Compactness & Space Very compact. High surface area to volume ratio. Saves significant space. Bulky and large. Requires more floor space and headroom. Heat Transfer Efficiency Very high. Turbulent flow at low Reynolds numbers ensures high heat transfer coefficients. Moderate. Flow is often laminar or transitional in the shell side, leading to lower coefficients. Cost Lower initial cost for standard materials (stainless steel) and duties. Higher initial cost due to more material and fabrication labor. Flexibility & Maintenance High. Capacity can be easily increased by adding plates. Easy to open and clean. Low. Fixed capacity. Maintenance is more complex and time-consuming (often requires tube bundle pulling). Pressure & Temperature Limited. Typically up to 25 bar and 150-200°C (gasket limitation). Brazed versions can go higher. Very High. Can be designed for extreme pressures (100s of bar) and temperatures (1000°C+). Fouling Resistance Good. High turbulence scrubs the plates, reducing fouling. Gasketed plates are easy to clean. Poor. Laminar flow zones and dead spots promote fouling. Cleaning tubes (especially the shell side) is difficult. Leakage & Mixing Low risk of cross-contamination. If a gasket fails, fluid leaks to the outside. Risk of cross-contamination. If a tube leaks, the streams can mix internally. Approach Temperature Can be very low (as low as 1°C). Excellent for temperature crossover duties. Typically higher (5°C or more). Less efficient for close temperature approaches. Applications HVAC, food & beverage, pharmaceuticals, low to medium pressure/temp industrial processes. Power generation, oil & gas refineries, chemical plants, high-pressure/high-temperature processes. |