Feasibility of Hydrolysis of Sludge Using Low Pressure Steam with SO2 as a Hydrolytic Adjunct and Utilization of the Resulting Hydrolysate

摘要

Sulfurous acid, when used with hydrolysis in the treatment of activated sludge, will increase soluble solids, improve filtration efficiencies and reduce moisture content of the resultant filter cake. Use of a 0.5% sulfurous acid and hydrolytic treatment of sludge at 140 degrees C for one hour increased the soluble solids content of the activated sludge by 20%. Concentration of the solubilized extract produced a syrup; 85% of the solids content of the syrup was organic. By TKN estimates, over 20% of these solids were proteinaceous. An amino acid analysis indicated it could be of value as an animal feed, and this was confirmed in rat feeding studies (at a 10% level in the diets) showing an efficiency of food utilization of 42 for the organic molasses as compared to 39 for cane molasses. (WRSIC abstract)