Energy efficiency measures - Industrial - Heat recovery - Petrochemical
Template assignment
Base Case
Proposed case
Template assignment
Base Case
- Steam is vented in a petrochemical plant having high temperature processes
- Process steam flow is 25,000 kg/h, operating 8,200 h/yr, pressure is 300 psig and temperature is 430°F
- 100% boiler make-up is preheated to 195°F
- Natural gas fired boiler seasonal efficiency is 80%
- Natural gas rate is $10.4/GJ
Proposed case
- Install new heat exchanger in series with the existing one to preheat the boiler makeup water at higher temperature
- Makeup is preheated to 235°F (instead of 195°F)
- Cost of retrofit is $400,000
- Install new heat exchanger to preheat a process stream using the
275°F condensate instead of steam- Hot stream: water condensate, flow 1.76 L/s, temperature 275°F, operation 8,200 h/yr, density 1,000 kg/m³, heat capacity
4.18 kJ/kg/°C - Cold stream: process stream, flow 4.33 L/s, temperature 150°F, operation 8,200 h/yr, density 700 kg/m³, heat capacity
2.6 kJ/kg/°C - Heat recovery efficiency is 88%
- Cost of retrofit is $600,000
- Hot stream: water condensate, flow 1.76 L/s, temperature 275°F, operation 8,200 h/yr, density 1,000 kg/m³, heat capacity
Base case
Proposed case
Solution
The worked-out solution is the data file selected from within the RETScreen Project Database. The user automatically downloads the Project Database file while downloading the RETScreen software.
The worked-out solution is the data file selected from within the RETScreen Project Database. The user automatically downloads the Project Database file while downloading the RETScreen software.
