preferably above 850 u00b0 c the injection system could be designed with an injection grid located horizontally or vertically co current or counter current of the flue gas flow the preferred solution would be to have a counter flow injection to minimize the impact on the downstream coils in the waste heat section additionally the invention could include the mixing of the vent with steam to avoid any condensation in the lines prior to and at the injection point in another embodiment of the solution the contaminated stream would be injected in the bottom of the furnace in one or more places in the flue gas tunnels temperature at the injection point should be in the range of 1000 u00b0 c to 1060 u00b0 c in order to ensure the full destruction of the vc beside the high temperature a sufficient residence time is important the preferred distance to allow the maximum destruction of the vc would be u2154 rd of the furnace length away from the flue gas exit this would provide enough residence time to ensure destruction efficiency over 99 the injection point should be carefully designed to avoid any impact on the refractory bricks of the flue gas tunnel and should ensure no liquid carry over into the firebox in another embodiment the contaminated stream may be injected on one or several side of the furnace at one or several locations in the preferred solution the.