Abstract: A two-stage distillation method for separating a mixed liquid such as a dimethylformamide-containing aqueous liquid or a methanol-containing aqueous liquid, into light and heavy fractions. The mixed liquid is first subjected to a distillation treatment in a first distillation zone of a vapor recompression type. When the boiling point of the mixed liquid is close to that of the desired light fraction, the top product from the first distillation zone is recovered as the light fraction, while the bottom product is subjected to a further distillation treatment to obtain the heavy fraction as its bottom product. When the boiling point of the mixed liquid is close to that of the heavy fraction, the bottom product from the first distillation zone is recovered as the heavy fraction, while the top product from the first distillation zone is subjected to a further distillation treatment to obtain the light fraction as its top product.

Abstract: Method and apparatus for heating and removing moisture from moist or watery material, wherein a watery material is introduced into one end of a rotating cylindrical drum having a section divided into a number of longitudinally extending compartments including a center compartment and circumferential compartments surrounding the center compartment and each accommodating freely disposed packing members. A hot gas is blown axially through the drum while the packing members in the respective compartments are caused to tumble in contact with the watery material to transfer the sensible heat of the hot gas thereto.

Abstract: A solid-fluid contacting apparatus, comprising an outer generally tubular housing member, preferably cylindrical in shape; an inner generally tubular housing member defining a fluid flow channel therein and being placed inside of the outer housing member and being generally coaxially aligned therewith, preferably concentrically, to define a space therebetween, preferably an annular space; at least one means extending radially between the inner and outer housing members for partitioning the space into a plurality of axially spaced contacting zones; at least one means extending axially within the inner housing member for partitioning the fluid flow channel into a plurality of fluid flow sub-channels; means in each of the contacting zones for receiving the solid; and a fluid flow inlet communicating between each of the subchannels and one of the contacting zones, a fluid flow outlet communicating between each of the contacting zones and its respective subchannel, and means positioned in each subchannel between t

Abstract: Disclosed is a method whereby a waste water containing ammonium ions, sulfate ions and organic substances is subjected to combustive disposal subsequent to addition of calcium hydroxide or calcium oxide thereto.

Abstract: A process for treating a hydrogen sulfide-containing gas in a closed loop system wherein said gas is passed through and absorbed by an alkaline aqueous absorbent containing an alkali carbonate and an oxidation catalyst. The solution containing the dissolved hydrogen sulfide is oxidized with an oxygen-containing gas to convert the absorbed hydrogen sulfide into elementary sulfur and sulfur salt compounds. After separation of the elementary sulfur from the solution, the solution is re-circulated for use as alkaline absorbent. A part of the re-circulated solution is diverted and subjected to mixed-combustion with an auxiliary fuel in a combustion furnace at an air ratio lower than 0.9 and at a temperature of 700.degree.C to 1100.degree.C to thermally decompose the sulfur compounds into hydrogen sulfide and an alkali carbonate.