Abstract: A vertical tube evaporation process for the concentration of saline water and other liquids, including the addition of an anionic mono-molecular dispersant thereto which interacts with materials precipitated during concentration and inhibits the formation of scale or fouling depositions on evaporator surfaces, and wherein the additive is incorporated into the precipitated materials and improves their removal during the descaling or defouling of evaporator surfaces by rendering such precipitates redispersable in fresh water or in a non-saturated liquid used for descaling or defouling of evaporator surfaces.

Abstract: Evaporation of saline water in a desalinization process, or evaporation of other types of liquid such as black liquor from paper pulp processing, is accomplished utilizing a multiple effect evaporator. Each effect includes one or more (e.g. first and second) sets of horizontally elongated dimpled plate evaporator elements. Horizontally flowing heating fluid, such as steam, is introduced to the internal passage of at least the second set in all the effects, and a head of circulation liquid is provided to cause liquid being evaporated to flow downwardly from the head over the external surfaces of the sets of dimpled plates in a thin film. The vapor evaporated is drawn through a demistor and is used as the heating fluid for the next effect. Recirculating liquid that has not evaporated and liquid separated by the demisting process are recirculated to the head associated with each effect. Clean condensate--such as distilled water--is withdrawn from the last effect.

Abstract: An evaporation system and process including an enclosed housing containing a plurality of shallow trays stacked vertically, one above another above a bottom-most heated reservoir with each tray serving as an evaporator and with the bottom of each tray serving as a condenser for the next lower tray and with the bottom of each tray sloping from the center outward to an outer collection trough and having a controlled supply of heat and feed liquid providing a substantially continuous supply of a regulated amount of feed liquid, with water being the primary example.

Abstract: An apparatus and method for fluid distillation in general, and in particular, of water, adapted for consumer or home use, but capable of being made and operated so that it is suitable for separating solvents and solutes and other industrial use. The apparatus includes a housing having divider structure to form one or more compartments for receiving water to be distilled. The divider structure also presents a fluid passage for receiving water vapor which is formed when the upper portion of the water in the housing is boiled by a heater. An aerator is provided in the housing below the heater and in a location within the water compartment. The aerator operates to direct air under a slight pressure into the water so that air bubbles can be generated in the water. The air bubbles will rise and break the surface of the water as the upper part of the water is being boiled by the heater.

Abstract: The invention provides a process for producing essential oils by plant hydro-distillation including the following steps:(a) loading the plants continuously into a still where they are processed counterflow wise with steam,(b) continuous unloading of the exhausted plants,(c) recovery of the latent heat of distillation and condensation of the steam by means of a gas in a condenser,(d) drying of the exhausted plants by contacting with the gas, in a drying installation,(e) combustion of at least a part of the dried exhausted plants in a boiler and use of the combustion heat for producing steam.

Abstract: The process for production of an aromate concentrate for use as a blending component for gasification fuel includes subjecting another feed hydrocarbon mixture to an extractive distillation using N-substituted morpholines as selective solvent in a extractive distillation column. Low-boiling non-aromates with a boiling range up to about 105.degree. C. practically completely and higher-boiling non-aromates with a boiling range between about 105.degree. and 160.degree. C. to a substantial extent are discharged as a raffinate from the top of the extractive distillation column. The extract bottoms from the extractive distillation are fed to a solvent stripping column where the solvent is at least partially recovered from other hydrocarbons. To eliminate condensation and polymerization products due to components with a boiling point over 170.degree. C.

Abstract: A column construction or boiling space in a distilling apparatus, having a pure vapor input connector, an input connector for water to be distilled, numerous heat exchange tubes within the column construction, a pure vapor removal connector, a condensate removal connector, and a connector for removing water to be distilled that has not vaporized. Pure steam is disposed to flow through heat exchange tubes, while impure water to be distilled is disposed to flow through an intermediate space between the heat exchange tubes. The heat exchange tubes are, at both ends, joined to flanges.

Abstract: Methods for removing volatile organic substances from water employ flash vaporization techniques. The methods comprise providing water which contains volatile organic substances and is at a pressure of at least about 35 psig, releasing the water into a vacuum chamber maintained under a vacuum in the range of about 1 to about 5 psia, removing resulting vapors from the chamber, and collecting liquid water from the chamber. At least a portion of the volatile organic substances originally contained in the water are removed as vapors from the vacuum chamber.

Abstract: The improved method and apparatus treats the stack gases from a commercial bakery oven to remove and recover pollutants, specifically ethyl alcohol. The method includes the steps of cooling the stack gases and passing the cooled gases through a packed column to condense the water and ethyl alcohol and if the ethyl alcohol is to be recovered drying the ethyl alcohol by distillation and by absorption of the water therefrom by a molecular sieve. The apparatus includes blowers and controls to maintain the normal flow of gases from the oven so that the removal and recovery of the ethyl alcohol from the stack gases does not interfere or change the baking conditions of the oven. This may be accomplished by a system of dampers or by controlling the discharge rate of the blowers used.

Abstract: A method of and system for recovering a solvent from a mixture of solvent and hydrocarbons, the system comprising at least two evaporation flasks successively fed with a charge consisting of said mixture to be separated, at least one steam generator performing the condensation of the solvent, a circuit for conveying the evaporated solvent and connecting the flasks to the generator and a circuit of an intermediate fluid in gaseous phase including a compressor for raising the condensation temperature of this fluid, the latter circuit connecting the generator to heat exchangers arranged upstream of each flask.

Abstract: A fractional distillation system is provided for fractionating unequal liquid mixtures with lower heat throughput and lower energy consumption. For mixtures in which the heavy fraction is predominant (FIG. 1), a stripper (2) pre-fractionates part of the mixture at lower pressure and at no extra energy cost by being reboiled by an intermediate condenser (3). The pre-fractionator temperature range is preferably nested within (overlapped by) the distillation column (6) temperature range.

Abstract: In the purification of ethylene oxide from an ethylene oxide-containing reaction formation gas produced by catalytic gas-phase oxidation of ethylene with a molecular oxygen containing gas, external thermal energy required for heating an ethylene oxide refiner is economized by a method which utilizes the diffusate obtained from the top of an ethylene oxide stripper as a heat source for the refiner. Further, the bottom liquid of the stripper can be used as a heat source for ethylene oxide refiner and/or a light ends stripper.

Abstract: A distillation device for distilling liquids, using concentrated solar energy to evaporate the undistilled liquid. A lens focuses solar rays into a concentrated area on the outer surface of an opaque heat target, the inner surface of which is in contact with the undistilled liquid in a container. The heat target evaporates the liquid, and the steam is condensed within a dome over the container, the dome having a plurality of cooling fins. The dome is cooled by compressed air, which circulates through an air conduit which spirals around the dome from top to bottom. The distilled liquid is conducted through a pipeline through the undistilled liquid in the container, and then out of the container.

Abstract: A process for the purification of 1,2-dichloroethane is described, in which the crude product, containing not more than 3% by weight of high-boilers, is distilled in a first column at 125.degree. to 180.degree. C. in such a way that the bottom product contains not more than 7% by weight of high-boilers. The purified, vaporous 1,2-dichloroethane discharged at the head of this column is used to heat product streams containing 1,2-dichloroethane. The bottom product from the first column is distilled in a second column, advantageously at a pressure of 5 to 40 kPa, together with a feed composed of vaporous 1,2-dichloroethane obtained from the reaction of ethylene with chlorine. The process makes it possible to purify 1,2-dichloroethane with a saving in energy.

Abstract: An ethanol-producing plant and a method is provided for producing ethanol from sugars, starches, or cellulose. Some ethanol-producing plants consume more thermal energy than they produce. The present invention solves the efficiency problem by utilizing an internal combustion engine with high-efficiency mechanical drives for providing the mechanical power requirements of the ethanol-producing plant and by utilizing the thermal energy of engine coolant and exhaust to provide some, or all, of the thermal energy requirements of the ethanol-producing plant. The method includes electrically loading the internal combustion engine to increase the thermal losses of the engine to equal the thermal energy requirements of the steps of the ethanol-producing process.

Abstract: An amine is separated from an aqueous solution of amine and volatile organic compounds by distillation in a column. The vapors generated during distillation are condensed. The condensed vapors are then passed into a separating device in which the volatile organic compounds are removed. The liquid remaining in the separating device is then fed to the head of the distillation column. Water is removed from the column in a sidestream and diamine is the residue. This process is particularly effective in recovering aromatic diamines from solutions which accumulate during hydrogenation of dinitro aromatic compounds.

Abstract: Method and apparatus are provided for simultaneously producing various forms of alcohol, including ethanol, which can likewise be withdrawn from the apparatus simultaneously. To this end, successive columns in the individual processing stages, each of which includes distillation, rectification, purification and dehydration, are connected in parallel for product flow but in series for energy flow and conservation.

Abstract: Dual interrelated distillation columns are disclosed wherein the heat for a first column is transferred by thermal conduction through a common wall or surface to a second column to increase efficiency and decrease waste of energy. In one embodiment, the first heat generating column is a cylindrical column, and the second column is an annular column concentric to the first column. This concentric arrangement permits the heat generated in the first column to flow outwardly into the second column, thereby improving its efficiency and reducing the heat loss. Typically, the inner first column is a high pressure rectifying column, and the outer concentric column is a stripping column. In an alternate embodiment, the inner column can simply be a portion of a high pressure distillation process, and the outer column is a portion of a lower pressure distillation column.

Abstract: Apparatus is provided for simultaneously producing various forms of alcohol, including ethanol, which can likewise be withdrawn from the apparatus simultaneously. To this end, successive columns in the individual processing stages, each of which includes distillation, rectification, purification and dehydration are connected in parallel for product flow but in series for energy flow and conservation.

Abstract: Desalination apparatus comprising a vessel, an evaporation surface for receiving saline water in the vessel, a condensation chamber arranged in the vessel beneath the evaporation surface, an evaporation chamber arranged in the vessel above the evaporation surface, a fresh water tank for containing a reservoir of fresh water and fresh water vapor thereabove, a first conduit connecting the fresh water tank and the condensation chamber, a pump for compressing in the condensation chamber fresh water and fresh water vapor to maintain a pressure-temperature differential between the condensation chamber and the evaporation chamber at the evaporation surface, a second conduit connecting the evaporation chamber and the fresh water tank for removal of fresh water vapor from the evaporation chamber and its delivery to the reservoir of fresh water, and valves and conduits for conveying saline water to the evaporation surface and for taking off fresh water accumulated in the fresh water tank.

Abstract: In a steam distillation process for the recovery of aromatic hydrocarbons wherein there is (i) a primary flash zone at the top of the distillation zone in which rich solvent is flashed and/or (ii) provision for the removal of side cut distillate vapors from about the middle of the distillation zone, the improvement comprising (a) heat exchanging flashed rich solvent vapors or side-cut distillate vapors with stripping water to provide stripping water vapors and stripping water at at least about the boiling point of water; (b) passing the stripping water vapors from step (a) to a steam ejector; (c) passing the stripping water from step (a) to a motive steam generator wherein the stripping water is vaporized under pressure; (d) passing the stripping water vapors from step (c) to the steam ejector referred to in step (b); and (e) passing the stripping water vapors, introduced into the steam ejector in accordance with steps (b) and (d), to the lower half of the distillation zone.

Abstract: A process for producing anhydrous ethanol, using an apparatus comprising a combination of a concentration column, an azeotropic distillation column and a solvent recovery column, and capable of effectively utilizing the vapor at the tops of the concentration column and the azeotropic distillation column, is provided, which process comprises:(i) connecting an absorption type heat pump functioning as a condenser and a reboiler at the same time, to either one of the concentration column or the azeotropic distillation column;(ii) connecting a combination of a mechanical type heat pump with a heat exchanger functioning as a condenser and a reboiler at the same time to another of the columns;(iii) using a back pressure turbine as a machine for driving the mechanical type heat pump; and(iv) using the back pressure steam generated by operating the mechanical type heat pump as the heat source for the absorption type heat pump.

Abstract: In the distillation of fresh water from sea water, the sea water is passed ownwardly in a falling film evaporator through a multiplicity of vertical tube evaporator (VTE) stages and multiple stage flash (MSF) evaporators. After the sea water passes through the first VTE stage where it forms a liquid component and a steam component, the liquid component is distributed evenly into the next VTE stage while the steam component enters an adjoining MSF stage. Condensed fresh water flows downwardly from one MSF stage to the next and experiences flash evaporation. The sea water or brine component and the fresh water distillate flow downwardly through the VTE and MSF stages so that the brine component can be removed from the final VTE stage and the fresh water distillate from the final MSF stage.

Abstract: Dual interrelated distillation columns are disclosed wherein the heat from a first column is transferred by thermal conduction through a common wall or surface to a second column to increase efficiency and decrease waste of energy. In one embodiment, the first heat generating column is a cylindrical column, and the second column is an annular column concentric to the first column. This concentric arrangement permits the heat generated in the first column to flow outwardly into the second column, thereby improving its efficiency and reducing the heat loss. Typically, the inner first column is a high pressure rectifying column, and the outer concentric column is a stripping column. In an alternate embodiment, the inner column can simply be a portion of a high pressure distillation process, and the outer column is a portion of a lower pressure distillation column.

Abstract: A desalinization apparatus includes a section for heating up input saline water using the heat released in subsequent water vapor condensation. A solar heater may be used to raise the saline water to a proper evaporation temperature, and a carrier gas is used as a vehicle for transporting water vapor from evaporation to condensation sections.

Abstract: Disclosed is a method for recovering pure aromatic substances from a mixture of hydrocarbons containing both aromatic and non-aromatic fractions. The input mixture is fed through an extractive stage provided with a preliminary distillation column. In the preliminary stage the aromatics-containing product is treated at a pressure up to 20 bar and a temperature up to 300.degree. C. The pressure is adjusted to a value at which the operational temperature of the preliminary stage is higher than the pressure and temperature in the extractive stage and the heat of the vapors discharged from the preliminary stage is used for heating the extractive stage.

Abstract: In a thermally driven multi-effect distillation process and apparatus liquid is introduced into a plurality of evaporating and condensing stages or chambers while heat energy is passed through the stages or chambers in a direction countercurrent to the direction of flow of the liquid which undergoes evaporation to form condensate and distilland in each stage or chamber while transferring the heat of condensation to the next downstream stage or chamber and maintaining a minimum temperature differential between stages or chambers, and separately removing condensate and distilland from each stage or chamber while rotating the stages or chambers about an axis passing through the points of introduction thereto of the liquid and heat energy. The apparatus includes a plurality of adjacent evaporation and condensation chambers and devices for introducing liquid and heat energy thereto in countercurrent directions. The walls of the chambers, formed of spaced heat conductive sheets, act to transfer heat.

Abstract: A method is disclosed for fractionating a hydrocarbon conversion zone effluent stream comprising at least three components which are to be isolated into separate streams. A two-column system for fractionating the effluent of a benzene alkylation zone is employed. The overhead vapor of a downstream second column is condensed in a side reboiler of a preceding recycle column. This side reboiler is located between the feed point to the recycle column and a separate reboiler located at the bottom of the recycle column. The utilities cost of performing the fractionation is reduced.

Abstract: A membrane distillation module is provided with a thin, flexible microporous membrane positioned against an impermeable condensor sheet that is stiffer in bending than the membrane. Distillate vapor diffuses through the membrane from the hot feed flowing rapidly past the membrane, and condenses and collects between, and in intimate contact with, the membrane and the condensor sheet. The condensed distillate is stripped by forces exerted by the hot feed acting on the distillate across the membrane, and flows toward a distillate outlet located in the downstream direction of the hot feed flow. Cold feed flows past the condensor sheet in the counter direction to that of the hot feed for absorbing the latent heat of condensation, and is subsequently additionally heated and introduced into the hot feed channel. Expanded microporous polytetrafluoroethylene (PTFE) is the preferred membrane material, and a spiral-wound assembly is the preferred configuration.

Abstract: In a combination alkylation-methyltertiary butyl ether (MTBE) operation, isobutane vapor side-draw and bottoms product yield from the alkylation fractionation, respectively, are used to indirectly heat the mid-section and reboil section of the methyltertiary butyl ether fractionator for heat conservation, beneficiating both the alkylation operation and the MTBE operation.

Abstract: A flow of fermenting liquor from a fermentor is separated into a yeast concentrate flow, which is recirculated to the fermentor, and a yeast-free flow which is separated in a simple evaporator unit into a first ethanol-enriched vapor flow and a first liquid bottom flow. The first vapor flow is treated to produce the desired ethanol while a major part of the first liquid bottom flow is recirculated to the fermentor. A minor, residual part of the latter flow is fed to a stripping unit where it is separated into a second ethanol-enriched vapor flow and a second liquid bottom flow exhausted of ethanol.

Abstract: An offshore water electrolysis plant which produces pressurized gas by electrolysis of fresh water and wave power includes the combination of a wave-powered electric generator at the ocean surface, an electrolyzer and storage vessels located on the ocean bottom for providing gas under pressure, and a source of fresh water at the ocean surface forced down to the submerged electrolyzer through the use of a water-filled standpipe. In one embodiment, the electric power generating system includes a tethered floating helix coupled to an electric generator, in which the helix is automatically aligned with the wave propagation direction, while in another embodiment linear alternators are mounted for reciprocation on a column which extends through the air-sea interface, with each alternator provided with a donut-shaped float, such that electric power is generated as each float moves vertically up and down responsive to wave motion.

Abstract: Solar distillation apparatus is disclosed in which the released heat of condensation of the condensing liquid is recovered in a transparent conduit disposed over the liquid to be distilled. Solar energy passes through the transparent conduit and is received on an undulated plate system over which the liquid to be distilled is conducted. A cooling fluid is circulated through the conduit to absorb heat released by the condensing liquid. In one embodiment, the conduit does not concentrate the solar energy. The conduit is preferably disposed at an angle of up to about 25.degree. with the horizontal so that the system is subjected to minimal pressure. In another embodiment the conduit defines a fluid lens system which concentrates the solar energy on the plate system. Provision is also made to recover heat from the condensate and a concentrate of the liquid to be distilled.

Abstract: A thermally driven multi-effect distillation process and apparatus are disclosed in which liquid is introduced into a plurality of evaporating and condensing stages or chambers while heat energy is passed through the stages or chambers in a direction countercurrent to the direction of flow of the liquid which undergoes evaporation to form condensate and distilland in each stage or chamber while transferring the heat of condensation to the next downstream stage or chamber and maintaining a minimum temperature differential between stages or chambers, and separately removing condensate and distilland from each stage or chamber while rotating the stages or chambers about an axis passing through the points of introduction thereto of the liquid and heat energy.Generally the apparatus comprises a plurality of adjacent evaporation and condensation chambers and means for introducing liquid and heat energy thereto in countercurrent directions.

Abstract: In a method for separating a hydrocarbon mixture into relatively difficultly soluble hydrocarbons and relatively easily soluble hydrocarbons by extractive distillation using a polar solvent comprising feeding the starting hydrocarbon mixture to at least two evaporators, an extractive distillation column, a stripping column and a rectifying column; the improvement wherein(1) the polar solvent discharged at a high temperature from the bottom of the stripping column is recycled to the extractive distillation column after it has been cooled to a suitable temperature by giving up heat to a reboiler of the extractive distillation column, a reboiler of the rectifying column and successively to the two or more evaporators, and(2) the starting hydrocarbon mixture is divided into two or more streams and heated in two or more evaporators, one stream being evaporated in a first evaporator to a pressure necessary for introduction into the extractive distillation column and then fed to the extractive distillation column, a

Abstract: An improved distillation method and apparatus are provided for recovering anhydrous ethanol from fermentation or synthetic feedstocks. The system includes at least one stripper-rectifier tower, a dehydrating tower, and an azeotropic agent stripping tower. Substantial energy savings are realized by operating the dehydrating tower, and preferably also the azeotropic agent stripping tower, at a higher pressure than the stripper-rectifier tower and by condensing the overhead vapors from the dehydrating tower (or dehydrating tower and azeotropic agent stripping tower) to provide the heat required in the stripper-rectifier tower. In a preferred embodiment, two stripper-rectifier towers are used, one operating at a higher pressure than the other, in which case the higher pressure tower is heated as just described and the overhead vapors from the higher pressure tower are condensed to supply the heat required in the lower pressure tower.

Abstract: A mechanical energy conversion method and system for the restoration of dissipated heat energy, contained in natural or artificial water bodies at or near ambient temperatures, to industrial process heat, mainly in the form of steam up to 200.degree.-400.degree. C. The sensible heat contained in a water body is concentrated as latent heat in low pressure water vapor which is thermo-compressed by steam ejection to an intermediate pressure level, wherefrom mechanical compression takes over, generating highly superheated output steam. The ejecting steam is not generated in a boiler, but is continuously regenerated by the compressor and routed back for repeated ejection. The compressor is driven by a heat engine whose reject heat is collected and upgraded as well. The output of heat energy is essentially equal to the sun of the heating value of the fuel consumed and the intake of latent heat and amounts thus to substantially more than the heating value of the fuel alone.

Abstract: A method for working up residues of an extractive distilling process for obtaining pure hydrocarbons. The residue from an extractive distilling column is fed to the about middle part of a distilling column. The hydrocarbons are distilled and removed at the head of the distilling column and the solvent is removed at the bottom of the distilling column. A sidestream is removed from the distilling column at a position above the feed plate for the residue from the extractive distilling column via a so-called reflux evaporator plate having an elevated level of liquid. The sidestream is heated by indirect heat exchange with the solvent flowing from the distilling column. The heated-up sidestream is fed back into the distilling column at a level at or above the reflux evaporator plate. The concentration of the solvent at the reflux evaporator plate is controlled by the amount of reflux at the head of the distilling column.

Abstract: The invention provides a means for reducing the energy consumed by thermally activated separation processes such as fractional distillation. This is done by recovering at least part of the reject heat from such processes and upgrading it for recycle back to input heat. The upgrading is accomplished by another low temperature source of heat which may also be the separation process reject heat. A simple and reliable heat pump using the reverse absorption principle is incorporated in the separation process to accomplish this upgrading.

Abstract: In a process for producing butadiene or isoprene having a high purity comprising a step of treating a C.sub.4 or C.sub.

Abstract: A multistage evaporator plant having combined vapor compressor and heat pump for recovery of the heat contained in the vapors. The evaporator section comprises several stages and a heat input, a condensate output and a vapor output. The vapor compressor can comprise a steam jet injector connected to a source of booster steam for providing steam power and connected to the heat input of the evaporator section, a distributor valve connected to an input of the steam jet injector.

Abstract: An apparatus for producing fresh water from sea water in which a vertical accumulator utilizes the sensible heat of sea water so as to evaporate said sea water to a temperature above 100.degree. C. under pressure, a heat-exchanger connecting between the upper and lower portions of said accumulator causes a high temperature liquid to effect heat-exchange with sea water to be evaporated, a fresh sea water feed line connected to the lower portion of said accumulator adjusts the pressure within the accumulator and an evaporator receives higher temperature sea water. The accumulator accumulates heat in such a manner that the upper portion of said accumulator holds higher temperature sea water and the lower portion of the accumulator holds lower temperature sea water so that when heat is accumulated, the amount of said higher temperature sea water increases and when heat is radiated, the amount of higher temperature decreases whereby sea water evaporates at all times.

Abstract: Substantially anhydrous, i.e., absolute, ethanol is distilled at high thermal efficiency from a dilute feedstock such as a fermentate ("beer") containing one or more low boiling components whose removal at least in part prior to anhydrous distillation is necessary in order to achieve an acceptable degree of phase separation in a decanter. Most of the low boiling component(s) are removed from the feed in a rectifying column with the balance of the low boiling component(s), insufficient in amount to seriously interfere with proper operation of the decanter, being removed from the system employing a light-ends column. Both the anhydrous column and the light-ends column are operated at substantially superatmospheric pressure with thermal values recovered from these columns being used in the operation of the rectifying column.

Abstract: A flow of fermenting liquor from a fermentor is separated into a yeast concentrate flow, which is recirculated to the fermentor, and a yeast-free flow which is separated in a simple evaporator unit into a first ethanol-enriched vapor flow and a first liquid bottom flow. The first vapor flow is treated to produce the desired ethanol while a major part of the first liquid bottom flow is recirculated to the fermentor. A minor, residual part of the latter flow is fed to a stripping unit where it is separated into a second ethanol-enriched vapor flow and a second liquid bottom flow exhausted of ethanol.

Abstract: A process and apparatus for the separation of components from a mixture which forms an azeotrope is disclosed by subjecting the mixture to extractive distillation to remove one of the components and regeneration to separate another component from the extracting agent added to the extractive distillation column. According to the invention, a first side stream is withdrawn from the extractive distillation column, passed in heat exchange with the bottoms from the extractive distillation column en route to the regeneration column and returned to the extractive distillation column at a point below the point at which it is withdrawn. A second side stream from the extractive distillation column is withdrawn, passed in heat exchange with the bottoms of the regeneration zone and returned to the extractive distillation column. For this purpose, separate heat exchangers are used for the respective side streams.

Abstract: A continuous method and apparatus for distilling a liquid include conducting the distilling liquid through at least two successive distillation units operating at different temperature levels. The distilling liquid is vaporized in each distillation unit and the obtained vapor condensed into distillate by conducting the vapor into heat exchange relationship with the liquid discharged from the evaporators in a succeeding distillation unit which operates at a lower temperature level. At least one of the distillation units includes a plurality of communicating distillation stages, each distillation stage including an evaporator and a corresponding condenser.

Abstract: A multi-stage evaporator is used to remove water from the extracted distillation or stripper tower bottoms recycled as quench liquid to the quench tower of an acrylonitrile purification and recovery system. This results in a significant decrease in the amount of waste quench tower bottoms produced by the system. Use of a multi-effect evaporator represents a significant energy savings as compared with other techniques for decreasing the water content of the recycle stream.

Abstract: A process for the substantially complete removal of acid gases and ammonia from aqueous solutions is disclosed, which comprises a two stage distillation operation wherein the pressure in the first distillation stage is substantially less than the pressure in the second stage, the ammonia concentration in this stage decreases downwardly so that an aqueous bottoms stream has a pH less than 8, this aqueous bottoms stream is treated with alkali and then distilled in the second stage. A portion of the aqueous bottoms can be vaporized by indirect heat exchange with vapors evolving from the second stage. The improvement lies in adding ammonia to the overhead vapor from the first stage to reduce corrosion of the condenser and preferably, the amount of vapor condensed is controlled to further minimize corrosion.

Abstract: A process for the production of alcohol from a fermented feed wherein insoluble organic matter is separated prior to entry into a first distillation column. The insoluble organic matter is dried under pressure to produce dried distillers grain and wherein excess vapor is removed from the drying zone to provide heat to the distillation system. The present process also includes removing excess water vapor from the evaporation zone, obtained from supplemental heating supplied by the overhead from said first distillation column, compressing said water vapor, and recycling it to the distillation columns and the evaporation zone.

Abstract: A method and apparatus for distillation wherein the heat of partial condensation and the heat of evaporation are incrementally utilized as produced thus guiding the gaseous phase of the distillation along the dew-point line of the enthalpy-concentration diagram and guiding the fluid phase along the bubble-point line of the enthalpy-concentration diagram of the mixture to be rectified.