Process to stabilize bioorganic, raw or treated wastewater sludge

  • US 5,417,861 A
  • Filed: 12/21/1993
  • Issued: 05/23/1995
  • Est. Priority Date: 11/30/1990
  • Status: Expired due to Term
First Claim
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1. A method of treating bioorganic or raw or treated wastewater sludge to provide a stable product for use as a beneficial soil or fertilizer for agricultural lands comprising the steps of:

  • treating the bioorganic or wastewater sludge with a high adsorbent material selected from the group consisting of cement kiln dust, lime kiln dust, fluidized bed ash, lime injection multistage burner ash, dry sulfur scrubbing residue, slag fines, pulverized calcium carbonate, fly ash, gypsum or a combination thereof to provide a sludge mixture, such that odorant sludge organics and inorganics are bound to the adsorbent particles,adjusting the pH of the sludge mixture such that it is in the range of 7.0-9.5,adjusting the conductivity of the sludge mixture such that it is raised to between 5 and 30 mmhos,adjusting the solids to a minimum of 50% andadjusting the microflora content within the range of about 106 to 1010 aerobic bacteria and about 104 to 107 fungi per gram soil solids, if necessary because of the absence of a sufficient microflora, with a soil, a sludge product containing microflora, a microbial culture or mixture thereof, by introducing the microflora of the soil, the sludge product or the microbial culture directly into the sludge mixture; and

    thereafter maintaining the pH range and conductivity range for a time sufficient to allow the microbial population of the sludge under the influence of the conductivity range to establish and to commence catabolism of the organics present in the sludge mixture, to continue the odor reduction initially begun by the addition of the adsorptive material, to prevent regrowth of pathogenic organisms, and to continue to carbonate any residual calcium hydroxide or calcium oxide components to form said stable product.

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