Abstract: A method of inhibiting calcium carbonate scaling in a multi-stage evaporation plant of black liquor by heat-treating calcium-containing liquor includes a first stage wherein the calcium-containing liquor is heated to about 110-145.degree. C. with direct contact with the heating medium; a second stage wherein the liquor is maintained at this temperature in a retention tank for 1-20 minutes to reduce the amount of calcium in the liquor by precipitating calcium carbonate; and a third stage wherein the heat-treated liquor is evaporated for combustion.

Abstract: A method and apparatus for forming an array of multiple parallel flow orifices, for example by holes drilled through a plate in a selected pattern and spacing and of selected sizes or flow diameters, and whereby these orifices are used to provide an approximately equal and adequate distribution of liquid flowing through them as parallel streams of liquid and into an evaporation zone or a parallel array of evaporation channels, and wherein the orifices can be adjusted in flow diameter to control the flowrate of liquid in generally parallel streams with an array of orifice adjusting apparatus, for example an adjacent sliding orifice plate which provides for orifice flow rate adjustment with orifices through this second plate corresponding in position to those of the first orifice plate, and the use of such dual orifice plates for supporting a pool of liquid there-above and for controlling the flowrate of liquid through the first array of orifices by reducing or enlarging their orifice flow diameters to control

Abstract: The wet process phosphoric acid evaporation, its clarifying, fertilizer production and fertilizer efficiency is improved in the presence of multi-component mixture of anionic surfactants and ammonium compound.

Abstract: Volatile components are eliminated from polyacrylate melts by distilling off the volatile components by a process in which the volatile components are distilled off under reduced pressure, entraining agents are added to the melts at above 100.degree. C. and the melts are simultaneously circulated.

Abstract: The invention relates to a process for the recovery of heat and chemicals from a mixture of ashes and spent liquor by carrying out the final concentrating (2) of the liquor, and its feeding (8) into the soda recovery unit (5), under pressure and at a temperature higher than the atmospheric boiling point of the liquor. According to the invention, the ashes (1) are not mixed with the waste liquor (7) until after the final concentrating (2) of the liquor, and the mixture is further expansion evaporated (4) before the thus concentrated pressurized liquor is fed into the soda recovery unit (5).

Abstract: A method and device for removing organic compounds from soil, solids, sludges and other types of contaminated materials utilizing a non-rotating contactor which can be tightly sealed from air infiltration. Binders such as cement, lime, flyash or kiln dust may be added to the soil prior to treatment so as to aid in the volatilization of the volatile organics and to immobilize the non-volatile constituents in the treated solids. The contaminated materials are fed to a chamber with a movable rake therein and are subjected to temperatures sufficiently high to violatize the organic constituents. The volatilized contaminants are purged with small amounts of air or other non-condensible gas and with superheated steam. The organic constituents can be captured in a vapor phase or they can be condensed and captured in the condensed liquid.

Abstract: The addition of a small amount of hydrogen or a hydrogen-liberating compound such as a metal hydride to a caustic solution serves to suppress the corrosive effect of the solution on nickel-based surfaces. Typical nickel-based surfaces include caustic evaporator surfaces which contain a caustic solution maintained at a temperature of from about 130.degree. C. to about 180.degree. C. A preferred metal hydride is sodium borohydride which is preferably present in an amount of from about 5 ppm to about 100 ppm. Concentrated caustic solutions containing less than 0.5 ppm of nickel can be prepared by this process.

Abstract: A low boiling, water soluble organic solvent is added to a saturated brine to thereby reduce the salt solubility of the brine and cause precipitation of the salt. The precipitated salt is filtered out and dried. The remaining brine-solvent mixture is distilled to remove the solvent which is reused. Unsaturated brine that is generally free of solvent is returned for resaturation with salt.

Abstract: A method of concentrating and drying water-containing fluent media, especially waste water concentrates, wherein an additive is incorporated in the water-containing fluent media for separating the solids thereof without the formation of scale and the liquid is evaporated. The additive comprises precipitates containing hydroxides, phosphates or arsenates of magnesium, calcium, zinc, aluminum or iron.

Abstract: Potassium silicate solutions combined with silanes that contain a hydrophilic functionality can be spray dried effectively to provide free-flowing powdered products.