Process Overview
The Plasma Thermal Destruction & Recovery (PTDR) waste-to-energy technology uses the heat generated by plasma arcs in an oxygen starved (pyrolytic) environment to first, pull apart (dissociate) the molecules that make-up the organic portions of the waste, then, depending on the composition of the waste stream, a controlled (stoichiometric) amount of oxygen (either in the form of steam or pure oxygen) can be added to reform the dissociated elements of the waste into a synthesis gas ("syngas"), consisting mainly of Carbon Monoxide (CO) and Hydrogen (H2). This process is commonly referred to as plasma gasification. The syngas can then be used in a variety of ways: as a fuel for thermal and/or electric energy production or as a feedstock for the production of liquid fuels, such as ethanol (i.e. waste to energy). The inorganic constituents of the waste are melted (vitrified) into an environmentally safe, leach resistant, glass matrix. The system derives its energy from plasma arcs, thus wastes with little or no calorific value can be effectively and efficiently treated.
Waste, when heated to a very high temperature using plasma arc in the controlled atmosphere of the reducing plasma gasification reactor undergoes predictable physical and chemical changes. This high temperature generated by the heat from the plasma arc, over 1,000ーC (1,800ーF) prevents the formation of complex organic molecules and breaks down organics into a gas. These primary molecules are stable above 965ーC (1,770ーF). The formation of dioxins or furans is impossible inside the plasma gasification reactor due to the unique process features, including high uniform temperatures generated by the heat from the plasma arc and a lack of excess oxygen within the system.
This hot gas is then fed through a gas cleaning and conditioning system, where it is rapidly cooled and cleaned to remove any entrained particulate and/or acid gases prior to potential re-use.
Plasma Thermal Destruction & Recovery (PTDR) plasma gasification reactors are designed to collect the molten metal and glass. The glass and metal layers are removed through controllable tap ports into a slag/metal collection system. The taps are connected to the slag handling system to allow automated removal of the slag upon operator command. Removal of the molten glass presents no hazards of any kind to personnel, requires no special tools and does not disrupt the operating process. The metal layer, which settles on the bottom of the basin in the processing reactor, below the molten glass, is tapped as necessary, depending on the metal content of the waste stream.
Plasma Thermal Destruction & Recovery (PTDR) waste-to-energy systems are driven by proprietary, state-of-the-art instrumentation and computerized control systems
In addition to the benefits associated with the recovery of useful products, the Plasma Thermal Destruction & Recovery (PTDR) waste-to-energy process results in the highest levels of volume and weight reductions of any treatment process.
The Plasma Thermal Destruction & Recovery (PTDR) waste-to-energy process is a unique, cost-effective and virtually emissions-free technology that is superior to other mainstream methods of waste treatment:
- The PTDR waste-to-energy process can utilize virtually any type of feedstock containing combinations of organic, inorganic and/or heavy-metal constituents.
- The PTDR waste-to-energy process brings inherent synergies whereby the treatment of inorganic and organic feedstocks can be processed together, thus the pre-processing, staging and management costs are minimized thereby reducing processing costs.
- Unlike most other treatment methods, the PTDR plasma gasification process does not create any secondary wastes that will require further treatment or landfilling. For example, incinerators produce large quantities of bottom and fly ash which are toxic in nature, require further treatment (with stabilization agents) and the resulting post-treated materials (with increased volume) will require final disposal, usually in specially designed landfills.
- For PTDR plasma gasification systems that are installed at the site where the waste feedstocks are produced (such as the PTDR-100 systems), there will be GHG reductions associated with the avoidance of transportation to the disposal sites.
Carbon credits are measured in units of certified emission reductions (CERs). Each CER is equivalent to one tonne of carbon dioxide reduction. Depending on the 'business as usual scenario', the waste stream(s) processed and the PTDR plasma gasification system type, hundreds to thousands of CERs can be generated in a given year.
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