A method for treating bioorganic or raw or treated wastewater sludge so that a stability based upon achieving a significant microbial population, conductivity level and percent solids, is developed rapidly, is provided for indefinitely and is independent of climatic conditions. A dewatered sludge that has not been treated (i.e., raw) or a sludge that has been treated to a PSRP level or a sludge that has been treated to a PFRP level, i.e., pasteurized or sterilized sludge when still in a wet condition, i.e., between 12%-30% solids, or when in a dry condition, i.e., between 30-60% solids, is mixed with alkaline adsorptive materials to reduce odor, to increase the percent solids and to facilitate granulation, is adjusted to a mildly alkaline pH, and is adjusted to an ionic conductivity which will allow the sludge to mature rapidly when seeded with a beneficiating microbial flora. This process will reduce the pH or a high alkaline treated sludge, e.g., often above pH 12, to a physiological pH of between 7 and 9.5 or will raise the pH of a treated acid sludge to a similar range so that microbial activity can proceed to facilitate stability. Heat may be applied to the mixture to accelerate the carbonation and aid the overall drying process. The granular product, substantially due to its active microbial population, is useful as an agricultural product and topsoil blend.

Document Type


Primary Class


Secondary Class

71/9; 71/13; 71/22; 210/613; 210/631; 210/667; 210/710; 210/752; 210/764; 210/916

Application Number


Filing Date

December 1993

Patent Number



N-Viro International Corporation

Publication Date


Patent Country





The University of Toledo


University of Toledo Libraries

Digital Publisher

Digital Initiatives


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Rights Statement

Rights Statement

No Copyright - United States. URI: http://rightsstatements.org/vocab/NoC-US/1.0/
The organization that has made the Item available believes that the Item is in the Public Domain under the laws of the United States, but a determination was not made as to its copyright status under the copyright laws of other countries. The Item may not be in the Public Domain under the laws of other countries. Please refer to the organization that has made the Item available for more information.