Thermoselect High Temperature Gasification (2)
Residues, Emissions and Waste Types Processed

Solid residues

Unlike incineration processes Thermoselect of Switzerland does not produce any chars, oils or ash that need subsequent treatment or disposal.

Rather, the mineral granulate is inert and vitreous, as it has been melted down at a high temperature (> 1600°C). The leachability of the mineral granulate (according to the German regulation DEV S4) is negligible.

Air Emissions

The primary emissions to air are made up of the exhaust gases from the power-generating unit which utilizes the synthesis gas. These emissions have been extensively tested and are monitored continuously for compliance. Content of heavy metals, cadmium/thallium and dioxins and furans is measured twice every year in the Karlsruhe Plant in Germany.
Emission levels are low, and when compared with the permitted values issued by the local authority (Regierungsprasidium Karlsruhe), as well as the stringent emission limits according to the German Law (17. BImSchV), the degree to which they are better than incineration is high.
In fact the permitted values are at least 70% lower than the current law, and the actual measured emission values achieved are even better and are at least 90% lower than the permitted values.

Flexibility: Waste Inputs

This process can handle a wide range of wastes. These include wastes with a lower calorific value, in the range of 6-18 MJ/kg, and with a moisture content of approximately 10%-60%. Liquid wastes such as sewage sludge can also be processed.

Raw and hazardous waste

The process can handle raw waste without prior treatment. It can also treat waste streams considered as hazardous, since the inherent conditions for process operation fully comply with the European Community Directive 2000/76/EC on the Incineration of Waste. This Directive states that 'if hazardous wastes with a content of more than 1% of halogenated organic substances ... are incinerated, [then] the temperature has to be raised to 1100°C for at least two seconds'.

As Thermoselect's high-temperature reactor is designed to guarantee gas residence times of at least two seconds at temperatures exceeding 1200°C, it is therefore suitable for treating Municipal Solid Waste (MSW). It is also suitable for the treatment of commercial and industrial waste streams as well, whether they are mixed together or separate.
Automotive shredder residue (ASR)
The process can also be used to recycle shredder dust from end-of-life vehicles, which is better known as Automotive Shredder Residue (ASR) and other post-consumer waste such as electronic devices. For example, in a three-day trial operation in the Karlsruhe plant in November 2002,9 ASR (with a chlorine content of up to 3.5%, a heating value of 10-17 MJ/kg, and high heavy metal contents), was fed through in fractions of 45%-55% in mixture with domestic waste - all without affecting normal disposal operations.
Thermoselect engineers compared the permitted air emission quality values of the average yearly air emissions of the Karlsruhe facility and those during operation with ASR. Comparison of the average values for 2002 with measurements taken during the ASR test shows that changing the input composition of the processed waste has no impact on the air emissions of the Thermoselect plant. The gas-cleaning train and its control concept is robust enough to compensate for changes in waste composition.
According to results of the trial operation, the Thermoselect process is able to process ASR, producing synthesis gas which can be used as a chemical feedstock. This qualifies the process as a 'recycling process' under European legislation.

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