High Capacity Direct Thermal (HCDT)
It is estimated that there are over 300,000 contaminated sites in China. Most are in urban centres. Most are scheduled for residential and commercial redevelopment. Most require a rapid turnover and all requiring strict adherence to strict remediation criteria.
Where high capacity and rapid turnaround for small to medium sized sites is required the mobile High Capacity Direct Thermal (HCDT) system is recommended.
HCDT is based on a unique Cascade Desorption system. The design, proven over 20 years of operation, allows for rapid blending and heating of contaminated soil in closed environment. The nature of the system significantly reduces the volume of the desorption chamber and therefore significantly reduces the volume of space and air that must be heated before volatilization of contaminants can begin. Combined with a pre-heating stage desorption times are reduced to < 5 mins. Desorbed gases are directed to an on-board Thermal Oxidizer where contaminants are destroyed at temperatures in excess of 900°C for 2 seconds ensuring compliance with US EPA, Canadian CCME, EU and Chinese GB 184484-1996 emissions standards. Treated soil is tested and safe for on-site infill.
The small volume of the desorption chamber, pre-heating of combustion air, efficient soil flow, and rapid heat transfer through exposure to super-heated air requires much less energy to achieve desorption temperatures between 450 and 600°C. The result is one of the lowest energy input costs in the industry and one of the lowest operating costs per tonne.
The HCDT can be provided on a single wheeled trailer or 12 metre ISO frame which allows for a single day set up and take down which minimizes downtime between projects and improve cost competitiveness.
Each HCDT system includes:
- Preheater with homogenizing auger
- Cascade Desorption Chamber (CDC) operating temps 400-600°C
- Main Burner/Oxidizer Burner (30 MM BTU)
- High Flow Extraction Fan
- Thermal Oxidizer (900°C, 2 seconds, >99% destruction)
- High Efficiency Heat Exchanger (ΔT 800°C)
- Pulse Jet Baghouse (>99.9% efficiency PM2.5)
- Control Unit