(JP6218398-A)      Waste materials (I) (wastewater treatment plant sludge, animal excrement, or process wastes) are sterilised, beneficiated and dried as follows: (a) (I) is settled and/or dewatered to a sludge cake contg. 4-60% by wt. dry solids and 40-96% H2O; (b) the cake is blended and reacted with alkaline earth metal oxides (II) (or mixts.), and CO2 in a container (Z1) so that the exothermic reaction between the constituents and intermediate reaction prods. (III) is retarded; (c) blended materials are overflowed to a reaction container (Z2) at atmos. pressure in the presence of O2 to effect an exothermic reaction between the H2O, (II), CO2 and (III) which initiates after up to 20 min. pref. 5-20 min; (d) the temp. in Z2 is allowed to rise rapidly to over 100 deg. C up to 117 deg.C, exceeding the bpt. of entrained liquids; (e) the H2O-content is allowed to reduce by evapn. to 50-10% or less; (f) the constituents are percolated to allow H2O vapour to escape from every reacted particle as the temp. reaches the bpt. of the liq., so that sterilisation is effected; and (g) the prod. is discharged.    ADVANTAGE -   The method using a delayed exothermic reaction produces sterile, safe prods. of uniform dryness, which may be packed and shipped long distances (e.g. to third world countries) without degradation for use as soil conditioners and fertiliser supplements to arid or non-productive land.    (EP601245-B1)      Waste materials (I) (wastewater treatment plant sludge, animal excrement, or process wastes) are sterilised, beneficiated and dried as follows: (a) (I) is settled and/or dewatered to a sludge cake contg. 4-60% by wt. dry solids and 40-96% H2O; (b) the cake is blended and reacted with alkaline earth metal oxides (II) (or mixts.), and CO2 in a container (Z1) so that the exothermic reaction between the constituents and intermediate reaction prods. (III) is retarded; (c) blended materials are overflowed to a reaction container (Z2) at atmos. pressure in the presence of O2 to effect an exothermic reaction between the H2O, (II), CO2 and (III) which initiates after up to 20 min. pref. 5-20 min; (d) the temp. in Z2 is allowed to rise rapidly to over 100 deg. C up to 117 deg.C, exceeding the bpt. of entrained liquids; (e) the H2O-content is allowed to reduce by evapn. to 50-10% or less; (f) the constituents are percolated to allow H2O vapour to escape from every reacted particle as the temp. reaches the bpt. of the liq., so that sterilisation is effected; and (g) the prod. is discharged.    ADVANTAGE -   The method using a delayed exothermic reaction produces sterile, safe prods. of uniform dryness, which may be packed and shipped long distances (e.g. to third world countries) without degradation for use as soil conditioners and fertiliser supplements to arid or non-productive land.