Waste to Energy –  A Promising Future

Introduction:

Clair has successfully commissioned a 12MW Waste-To-Energy plant for a client located in Delhi, India. The system was installed in 2016. The plant has been running successfully and is the only plant in India where the fuel used is RDF (Refuse Derived Fuel). Clair has provided semi-wet system for handling of the acidic pollutants, heavy metals, dioxins, furans and particulate matter. The plant has the capacity to handle an RDF feed of 550 TPD.

The exhaust flue gases from WTE based power boiler are led directly into a reactor. In the reactor, flue gas gets into contact with reagents in slurry form to remove the gaseous pollutants. Slurry into reactor is injected in sub-micron size particles with the aid of specially designed Rotary Atomizer to ensure effective reaction between gaseous pollutants and reagent. Immediately after reactor, dry Powder Activated Carbon (PAC) is injected into the flue gas duct and this flue gases are treated in a specially designed Bag filter where heavy metals, dioxins and furans along with dust is removed. The gases which are neutralized for acidic pollutants carry reaction products and particulate matter. These are separated in the bag filter.

SNCR system was provided to control NO_X emissions from the boiler. Urea (40% solution) solution is sprayed inside the boiler to convert NO_X into molecular nitrogen and water vapour. The system was designed to meet Euro Emission norms and the system has been achieving the norms since its installation. The uncontrolled emissions from boiler to which the system has been designed and the emissions after treatment have been listed in table 1.

Data/ Table:

Table 1: Semi-Wet System Parameters

Picture: