| |
 |
Environmental Fact Sheets |
 |
 |
 |
 |
 |
 |
|
Site decontamination/restoration : Circulating fluidized-bed combustor (cfbc) system - Cintec Environnement Inc. (F1-08-95) |
|
 |
|
 |
|
|
|
|
Description of the technology |
|
|
|
|
|
Español
The Circulating fluidized-bed combustor (CFBC) system developed by Cintec allows thermal destruction of organic contaminants, notably PCBs, contained in contaminated soils, solid or liquid wastes and sludges.
The circulating fluidized-bed thermal unit is made-up of the following elements:
- a combustion chamber and cyclone,
- a gas cooling system,
- a sleeve filter to catch dust,
- a dry purification system using hydrated-lime injection,
- an induced-draftfan to discharge gas at the stack
- a chimney,
- a continuous control system,
- a computerized control and recording system.
| 
| | The contaminated soils, solids and liquids are introduced into the incinerator's combustion chamber which initially consists of a bed of preheated sand. A forced-air current is maintained in the bed (fluid-bed) so that matter introduced into the combustion chamber is immediately sucked into it. The great turbulence to which the contaminates are subjected in the chamber, and the kiln temperature (approximately 950°C) allow destruction of the organic components, such as PCBs, which are present in the contaminated material. | | The system functions 24 hours a day. It produces neither wastewater nor sludge. The smoke treatment residues are sent to authorized treatment or disposal sites. The treated soils can then be used as landfill or for civil engineering works, if the residual contamination permits.
Rainwater in contaminated zones, and grey-water discharged from on-site trailers may contain certain pollutants. If necessary, the water is treated before being discharged into the environment.
|
|
 |
|
 |
|
|
|
|
Performance |
|
|
|
|
|
The technology is designed to treat from 500 to 5,000 kg of contaminated material per hour (including clay matrix).
The CFBC system can destroy hazardous wastes, including PCBs, with a destruction and removal efficiency exceeding 99.9999%. The CFBC conforms to and surpasses the emission norms dictated by the American Environmental Protection Agency (EPA), the Canadian federal regulations and the Quebec regulations and guidelines.
In comparison with other thermic systems, the CFBC offers the following advantages:
- An efficiency of combustion exceeding 99,9
- For atmospheric emissions : - dioxins and furanes < 0,5 ng/m3R
- HCl < 75 ng/m3R
- Particles < 20 ng/m3R
- Very low nitrogen oxide emissions (NOx)
Process diagram of the Cintec Group's CFBC
 |
|
|
|
|
|
|
|
|
Limitations |
|
|
|
|
|
The technology cannot be used to treat inorganic contamination. |
|
|
|
|
|
|
|
|
Installation and operation |
|
|
|
|
|
Cintec's CFBC system is made up of easily transportable modules. These modules can be carried by standard heavy-load trucks (no special permit needed). The system takes six to eight weeks to assemble. It occupies a 20 m by 25 m work platform and is 18 m high. After use, the whole system is dismantled and moved to another project.
Installation of the CFBC unit must respect the siting restrictions set out in the Règlement sur les déchets dangereux (Q-2, R.12.1, article 26).
A CFBC unit is operated by one to five workers (some of whom must be specialized) per shift. These persons are to be provided with adequate protective equipment. To ensure on-site safety, the following features are provided:
- in-chimney continuous control of atmospheric emissions;
- immediate automatic shut-down of the process if any parameter exceeds established limits;
- preparation of an emergency plan specially adapted to each site;
- constant monitoring of operations by a qualified staff;
- rigorous analytic follow-up of input and output.
|  |
Back-up energy to the reaction of combustion can be propane or natural gas. The entire installation require a power supply of 800 A (460 and 550 V).
|
|
|
|
|
|
|
|
|
Costs |
|
|
|
|
|
Cintec Environnement inc. sells treatment services using the CFBC technology. The costs vary according to the types of contaminants present, their concentration, the nature of the matrix, the percentage of chlorinated compounds, the volume to be treated and the selected site. |
|
|
|
|
 |
|
 |
|
- Four CFBC units are in existence at the present time: two are operating in Germany and two are owned by Cintec Tredi. One of them have been used to treat PCB-contamined material from Baie-Comeau in Canada. The second is put for sale because this contract is expired. The CFBC system made it possible to accomplish one of the most important PCB elimination projects, more than 100,000 tons in a wildlife reserve in Alaska. In Baie Comeau, close to 1,000 tons of contaminated materials were treated, more than half of which (555 tons) come from private owners in the area.
 |
|
|
|
|
|
|
|
|
Contacts |
|
|
|
|
|
 | CINTEC ENVIRRONNEMENT INC. | | GENERAL MANAGEMENT | | 7475, boul. Newman, suite 309 | | Ville Lasalle, Quebec, H8N 1X3 | | | | Phone : | (514) 364-6860 | | Fax : | (514) 365-2964 | | E-Mail : | cintec1@cintec.ca | | Web site : | http://www.cintec.ca |
|
|
|
|
|
|
|
