We all know that we need to reduce our emissions to help combat climate change. At CTEC, we offer a range of solutions designed to remove dioxins and improve air quality. Play your part and protect the planet. Contact us today.
Reducing emissions to protect our environment
The CTEC system controls the emissions during and after the advanced conversion chamber. Advanced conversion is controlled by Exhaust Gas Recirculation (EGR) providing a specific environment control, using tertiary EGR fed in at the primary stage in order to cool the main gasifier frame, then at the end for final stage, through 2 perforated side plates located at the first half of the gasifier. This controls the gasification, partial advanced conversion, total advanced conversion and ash final conversion.
The Gasification process takes places at temperatures above 600 degs C, the exact temperature depends on the characteristics of the waste. In order to promote the gasification of plastic a percentage of biomass is required, most waste already consists of this biomass, if not biomass is added. The CTEC system is a moving-bed-gasifier the waste slowly moves over 27 minutes along the inclined bed counter current EGR blasts the waste. In this arrangement, hot synthesis gas from the gasification zone is used to preheat and pyrolyse the downward flowing waste, massively increase the efficiency of the system. This CTEC moving bed steps offer extremely good mixing between waste and EGR. The syngas then passes into its secondary changer where it is combusted just like natural gas is on your cooker hob at home.
Bag Filters & Sorbent Injection
The installation of Emission bag filter and sorbent injection neutralises pollutants in the gas stream, the bag filter is predominately filtering Dioxins and Furans, Sulphur Dioxide and total particular matter. We condition the gas stream to a perfect gas velocity downstream of the bag filter, this promotes perfect mixing of 2 separate lines of hydrated lime and activated carbon for chemical reactions to take place before entering the bag house.
High Temperature Cyclone & Cooling chamber
Exhaust gas recirculation enters upstream of the cooling chamber changing gas temperatures from 1200°C down to 600°C. Temperature drop changes the state of sticky salt tars into ash which can then be recovered up to 85% in the cyclone.
The cyclone design follows a basic principle that the height of the unit is considerably greater than the unit diameter. This induces the swirling air or gases to follow a long spiral path, subjecting any particles to centrifugal separating forces for a maximum period of time. The gas inlets and outlets are proportioned and positioned in such a way as to present a smooth, uninterrupted flow without undue turbulence which would otherwise interfere with good dust separation.
Due to the clean combustion of the gasifier NOx emission is already minimal and doesn't require any further NOx abatement according to EU regulations. However to further reduce the NOx to a new industry low standard CTEC can use the following solution, taking into account the special requirements for catalytic installation. The solution is to take the clean gas back stream from the polishing ( carbon trap) stage, at 170°C temperature in order to re-heat it up to 250°C through a special heat exchanger located between the cyclone and superheated exchanger. This will reduce the NOx content to be less than your car exhaust emission.
Designed to remove dioxins that may pass through gas clean up bag filter. Requirement dependent on dioxins levels in waste.
With the addition of a water scrubber system this will further greatly reduce the emissions to virtually zero. Also particulate emissions of heavy metals are significantly reduced, further contributing to improvements in air quality. The separation is via water filtration membranes.
The total CO2 reduction is projected to achieve >80% of the typical CO2 emission from a typical incineration plant. Therefore the combustion of 1000 kg of waste in a CTEC gasification system will have approximately saving of 880 kg or more of CO2 per hour over typical incineration technology.