u00b0 fahrenheit reacted waste products leave the reactor and enter the expansion chamber 85 through a rotary metering valve 15 this valve meters flow into the expansion chamber 85 by varying the dwell or measure of volume exposed in the expansion chamber while the valve opening exposes the reactor exit to the expansion chamber by metering flow into the expansion chamber 85 the pressure of the reactor is regulated a pressure rise in the reactor 75 is relieved by releasing into the expansion chamber 85 more gas mass than is being forced into the reactor 75 by the compressor expansion of reacted gases against the piston 81 produces work greater than that required to power the compressor condensed water vapor and other gases pass from the expansion chamber 85 by upward travel of the expansion piston 81 by reducing the volume of the expansion chamber 85 the cycle will be examined in detail by first describing the mixing of air waste and water the waste and water are premixed before atomization and mixture with air an atomization nozzle either air atomized or hydraulically atomized can be used to produce droplet sizes less than 300 microns air atomizing nozzle can produce droplet sizes less than 100 microns small droplet sizes and their surface to volume ratio are necessary to absorb heat generated from the air during compression ignition of volatile components can be avoided during compression or even before entering the reaction zone by properly sizing the atomized droplet proper selection of the atomized droplet determines air and water temperature for example a droplet size of 1 micron is estimated to reach 315.