Batch Processing
CES plants process waste in batches rather than on a continuous basis as is the case with incineration plants. While incineration appears to have an advantage in terms of speed, this is offset by the need to create very large plants with very large initial capital costs and the inability to resize plants post-construction. In addition, achieving a rapid continuous burn of waste typically necessitates that waste be shredded or pelletized, and that the waste be physically disturbed in order to rapidly expose the surface area to oxygen and heat. While all this chopping, shredding, and churning achieves a rapid burn rate, it also creates substantial particulate waste which must be extracted before the exhaust can be released into the atmosphere. Burning waste also requires rapid exposure to very high temperatures, eliminating the possibility of extracting recyclable materials from the waste stream, and producing significant amounts of "slag": a heat-fused mass of metal, glass and other non-combustible materials. Slag output can equal 10-20% of the waste mass entering an incinerator and recyclables are not recoverable.
The CES batch process has many advantages over other disposal methods:
Generating Consistent Syngas Output
While batch processing is superior in allowing for modular, scalable systems with low particulate emissions, syngas production varies significantly through the production cycle. As depicted in the graph below, as waste is heated in the gasification module some substances gasify at lower temperatures than others, and once the supply of carbon-based substances in the gasification module is exhausted, syngas output declines rapidly.
The CES batch process has many advantages over other disposal methods:
- Application of heat over time allows thorough gasification of waste at moderate temperatures, allowing recovery of recyclable metal and glass post-processing.
- Superior volume reduction: 95-99%.
- Heating process involves no churning or mixing of waste. Treating the fuel source “gently” results in low particulate emissions reducing filtration system capital and maintenance costs.
- Batch processing allows for modular construction. The CES scalable modular design that can be precisely sized to meet disposal needs of a particular site without expensive redesign.
Generating Consistent Syngas Output
While batch processing is superior in allowing for modular, scalable systems with low particulate emissions, syngas production varies significantly through the production cycle. As depicted in the graph below, as waste is heated in the gasification module some substances gasify at lower temperatures than others, and once the supply of carbon-based substances in the gasification module is exhausted, syngas output declines rapidly.
Efficient energy production requires a consistent flow of syngas to generate heat and power a generator. To achieve consistent output while retaining the benefits of batch processing, CES plants are comprised of an array of gasification modules, operating on a carefully sequenced time cycle. As shown below, proper sequencing of multiple gasification modules allows for a consistent level of gas output using batch production.
Sequenced production across multiple gasification modules also allows efficient use of labor. Loading, cleaning and recyclables recovery, and gasification operation are timed to allow large plants to be operated with minimal labor. While one module is heating, another can be loaded, then recyclables removed from another, and so on.
