摘要 |
An animal waste treatment system, particularly adapted to process the waste from a large-scale confined animal facility, has two treatment cells and a holding reservoir. Each of the treatment cells has an anaerobic zone which is two to five feet deep and an aerobic zone on top of the anaerobic zone which is at least twelve feet deep. Effluent from the facility is introduced into the anaerobic zone of the first cell; the aerobic zone of the first cell has a fluid connection to the anaerobic zone of the second cell. Residence times are preferably twenty-one days per cell. The aerobic zone is created by the injection of air with a coarse aerator. Oxygen introduced by the aeration oxidizes reduced nitrogen compounds and other volatiles; much of the nitrogen escapes as N2 to the atmosphere. A portion of the cleaned water is returned to the facility for dilution and flushing purposes. The rest of the cleaned water is used to irrigate crops. The present invention also has application to nonagricultural uses, such as to subdivisions which are unable to obtain connections to city sewer systems.
|