Method for treating soil contaminated with hydrocarbons

摘要

A method for treating soil that has become contaminated with hydrocarbons or other organic material includes straining the contaminated material through a rotary air lock into a preheater and pneumatic conveying by primary air into an oxidation chamber. Secondary air is directed into the oxidation chamber through a plurality of perforations in the wall of the oxidation chamber to combine with and sustain the fluidized state of the soil-gas mixture. The primary and secondary air is preferably produced by passing the proceeds of an air blower through a pre-heating assembly to produce hot air. The oxidizer is arranged at an incline so that the gas solid mixture of hot air and contaminated soil flows upwardly. The temperature of the fluidized bed is controlled by the temperature of primary air so that lighter hydrocarbons spontaneously ignite in the oxidation chamber. The exothermic combustion causes the remaining organic material present in the contaminated soil to vaporize and burn. The product of this flash oxidation process is a mixture of treated soil, excess hot gas and gaseous and solid oxidation products. This mixture is separated such as by one or more cyclone separators to produce treated soil and process gas.