US Patent 7931860 Waste treatment apparatus and method

An apparatus for treating waste comprises a gravity drop steam heating tower for heating the waste to the biological kill temperature using pressurized steam, a first feed member for feeding the waste to be sterilized to the gravity drop steam heating tower, and a vaporization system. The vaporization system includes a heating chamber for facilitating vaporization of liquids in the waste, a conveying member for conveying the waste from the lower end portion of the gravity drop steam heating tower into and through the heating chamber, and a vaporization chamber for receiving the waste from the heating chamber and for releasing vapor entrained in the waste into the vaporization chamber.