Hch. Bertrams Aktiengesellschaft

Bayer Aktiengesellschaft

Bertrams Ag

Hans L Kuhnlein

Hans R Kung

Hans Guth

Hermann Wieschen

Hans-Joachim Kaiser

Klaus Kleine-Weischede

Wolfgang-Dieter Muller

Georg Molnar

Karl-Heinz Schultz

Joachim Maas

Walter J Jarosch

Jurgen Groening

Hansruedi Forter

A method and apparatus for the concentration of an alkaline solution to an approximately anhydrous melt using the falling-film principle under atmospheric pressure wherein the solution to be concentrated is conducted along the internal surface of evaporator tubes (1). Each tube (1) is surrounded by a heating jacket (2). The heating jackets (2) are fed with heat-transfer fluid from a conduit (6) which is common to all jackets. An annular collecting trough (8) is associated with the lower end of each evaporator tube (1). The metal running off from the tube (1) is collected by the trough (8) separately from the vapors. All of the troughs (8) are connected to a melt discharge line (9) which is also common to all troughs. The vapors descending in the tube (1), in contrast thereto, pass through the opening (8a) of the collecting troughs (8) into a collecting duct (10) which is common to all troughs. By the separation of the melt and vapors at the tube end portions, a renewed drop in the alkali concentration is avoided.

Process and apparatus for the concentration of an alkaline solution

An alkaline solution film flowing from the top toward the bottom in falling-film evaporator tubes (1) is heated by a heat-transfer fluid flowing from the bottom toward the top in a narrow heating jacket (5). Since large temperature differences occur between the heat-transfer fluid and the alkaline solution film in the upper heated portion of the evaporator tube (1), in contrast to the lower portion, especially at high flow rate as it occurs in a narrow heating jacket (5), the heat flow density can at that location lead to a lack of wetting of the evaporator tube. To avoid such critical heat flow densities, the upper section (5a) of the heating jacket (5) is conically widened and thus the flow rate in this section is reduced to such an extent that a critical heat flow density is not reached at that point.

A process for purifying a polluted fluid which comprises heating the polluted fluid and evaporating the components of said polluted fluid which are more volatile while simultaneously concentrating the pollutants into a residue, introducing said residue to a combustion chamber where it is at least partially burned and introducing the heat of combustion as the only source of heat to the evaporation stage of the process.

Process for purifying polluted fluids

The invention procides a circulation evaporator for concentrating mineral acid, particularly sulphuric acid, comprising parts of, or at least coated with, enamel, characterized by a heat exchanger for heating the acid comprising at least one acid feed pipe provided with an enamel layer, means being provided to maintain the compressive stress in the enamel layer under all working conditions, said acid feed pipe being connected at its inlet end to a circulation pump and at its outlet end to a flash evaporator for concentrating the heated acid, this evaporator being connected by a circulation pipe to the pump inlet and to means for introducing the crude acid, for discharging the concentrate and for carrying away the vapors.

Evaporator for concentrating mineral acid, particularly sulphuric acid

A process and apparatus for purifying waste water which comprises introducing said waste water into a separation zone, removing a portion of the impurities recovered from said separation zone, and concentrating said impurities by their introduction into an evaporation system to form a still fluid residue and remaining impurities composed of impurities in gaseous and vapor form together with waste vapors, transferring said remaining impurities to an oxidation chamber, and supplying said oxidation chamber with heat and air, thereby oxidizing said remaining impurities through spontaneous combustion, wherein the proportion of the low boiling-point impurities in the waste water introduced into the separation zone is adjusted to a predetermined value.

Process and apparatus for purifying waste waters

The heat transfer apparatus comprises a storage reservoir containing salt as a heat carrier with a heater connected into the reservoir to heat the heat carrier so as to maintain it above the freezing point. The heater may comprise an electric heater or a fluid which is circulated for example from a separate heat exchanger. An intermediate heat exchanger is connected so that the salt is circulated therethrough and in heat transfer relationship to an intermediate heat carrier such as a metal alloy which is circulated from a consumption heat exchanger. The intermediate heat exchanger is in heat exchange relationship with a consumption heat carrier.

Heat transfer installation having storage reservoir containing a salt as

A corrosive liquid such as sulphuric acid is concentrated using two spaced concentric tubes. A film of the acid flows down the inside of the inner tube and hot flue gases contact the outside of the outer tube. Advantageously, the inner tube transmits radiant energy, e.g. is made of quartz, so the outer tube heats the inner tube by radiation. This absence of mechanical stress on the inner tube increases its life. The water vapor is taken off at the top of the inner tube and concentrated solution at the bottom. If desired, the tubes could be reversed with the flue gases going through the inner tube and the outer tube being of quartz with the liquid flowing on its outside.

Process and apparatus for concentrating corrosive liquid using radiant

A multi-stage apparatus suited for concentrating sulphuric acid comprising at least one high temperature stage and one low temperature stage, the high temperature stage including a surrounding wall defining a flue gas channel, means for delivering hot flue gas to said channel, and means for withdrawing from said channel cooled flue gas, the flue gas heating said surrounding wall which in turn imparts heat to material to be heated thereby, the low temperature stage including a heat exchanger with a first flow path for a heating agent and a second flow path for a material to be heated thereby, means for supplying the said second flow path material to be heated, means for withdrawing from said second flow path material after having been heated therein, and means for withdrawing from said first flow path spent heating agent, the means for withdrawing cooled flue gas from said flue channel of said high temperature stage forwarding heat from said cooled flue gas to said first flow path of said low temperature stage to serve as the heating agent in said low temperature stage. Advantageously the high temperature stage involves transfer of radiant energy from a surface heated by hot flue gas to a falling film of sulphuric acid flowing down a quartz tube separated from the radiating surface by an air space. An intermediate heating stage may be provided in which the cooled flue gas heats an exchanger liquid which is the heating medium in the low temperature stage.

Multi-stage apparatus for concentrating sulphuric acid

In the processing of a corrosive liquid mixture, such as 50 to 80% aqueous sulfuric acid, by its passage over one surface of a wall of inert heat resistant material, and heating the other surface of said wall, thereby to evaporate from said corrosive liquid mixture the more volatile component thereof, the improvement which comprises heating said wall by contact with an inert liquid material, and heating said inert liquid material indirectly through heat exchange with a normally solid molten material. Desirably the wall of inert material is a pipe surrounded by a molten metal in a first annular jacket and a molten salt in a second annular jacket.

Growing community of inventors

Fuellinsdorf, Switzerland

Hans L Kuhnlein