Process for treating liquid septage and biosolids
OwnerRoger A. Hickeyinventor
Life of this patent
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Abstract
A process for treating liquid septage and other biosolids having the steps of placing a known amount of liquid septage in a tank, mixing in a sufficient quantity of alkaline material to raise the pH to a desired level, storing the pH adjusted septage for a predetermined period of time, dewatering the septage, and pasteurizing the resultant dewatered solids cake. The process for treating liquid septage and biosolids disclosed by the current invention meets the Class A vector attractant reduction and pathogen reduction requirements mandated by the U.S. EPA. The end product of septage and other biosolids treated using the process disclosed by the current invention can be sold as fertilizer, and utilized without any additional permits.
Claims31
A process for treating liquid septage;
- said process comprising the steps of:
- removing substantially all debris, trash, and other non-organic matter from a known amount of liquid septage;
- placing said septage into a mixing tank;
- adding an amount of alkaline material that has been determined based on the quantity of liquid septage, the pH level of said septage, the lime demand of said septage, and the alkalinity of said alkaline material;
- mixing said alkaline material and said septage until the entire quantity of said septage reaches a predetermined pH level;
- storing said septage for a predetermined period of time;
- testing said septage at predetermined intervals of time to ensure the pH is maintained at predetermined levels;
- dewatering said septage by removing the free liquids from the solids in said septage thereby producing a dewatered solids cake;
- and
- heating said dewatered solids cake to a predetermined temperature for a predetermined time.
A process for treating liquid septage;
- said process comprising the steps of:
- removing substantially all debris, trash, and other non-organic matter from a known amount of liquid septage;
- placing said septage into a mixing tank;
- adding an amount of alkaline material that has been determined based on the quantity of liquid septage, the pH level of said septage, the lime demand of said septage, and the alkalinity of said alkaline material;
- mixing said alkaline material and said septage until the entire quantity of said septage reaches a predetermined pH level;
- dewatering said septage by removing the free liquids from the solids in said septage thereby producing a dewatered solids cake;
- storing said dewatered solids cake for a predetermined period of time;
- heating said dewatered solids cake to a predetermined temperature for a predetermined time;
- and
- testing said septage at predetermined intervals of time during said process to ensure the pH is maintained at predetermined levels.
A process for treating liquid septage;
- said process comprising the steps of:
- removing substantially all debris, trash, and other non-organic matter from a known amount of liquid septage;
- mixing said septage with an amount of alkaline material sufficient to raise the pH of said septage to at least 12 for 2 hours and at least 11.5 for an additional 22 hours;
- adding a polymeric flocculent to said septage;
- dewatering said septage by removing the free liquids from the solids in said septage thereby producing a dewatered solids cake;
- and
- heating said dewatered solids cake to a temperature of at least 70° C. and maintaining said dewatered solids cake at that temperature for a period of at least 30 minutes.
A process for treating liquid septage;
- said process comprising the steps of:
- removing substantially all debris, trash, and other non-organic matter from a known amount of liquid septage;
- mixing said septage with an amount of alkaline material sufficient to raise the pH of said septage to at least 12 for 2 hours and at least 11.5 for an additional 22 hours;
- adding a polymeric flocculent to said septage;
- and
- dewatering said septage by removing the free liquids from the solids in said septage thereby producing a dewatered solids cake.
Dependencies are inferred from the claim text.