Abstract: A process and processing system are disclosed that provide for the processing of many forms of waste, such as medical and food waste, that both reduces the volume of waste solids and neutralizes the biological activity of such waste, thereby facilitating the disposal of potentially unhealthy or hazardous materials. Biological neutralization is accomplished by chopping the waste material and mixing it with a circulating stream of fluid such as water that is superheated to a temperature which effects disinfection or sterilization in accordance with the needs of the user. The superheated fluid is maintained substantially in a liquid form to facilitate intermixing with the waste material and absorption thereby in instances of the processing of fluid-absorbable materials. The processed waste can be filtered to remove solid particles having a size in excess of a predetermined amount, and the filtrate can be passed into municipal sewer systems.