Showing papers on "Mixing (process engineering) published in 1972"

The behavior of suspended solid particles and liquid in bubble columns

Abstract: The longitudinal concentration distribution of solid particles and liquid mixing in 6.6, 12.2 and 21.4 cm i. d. bubble columns were measured and were analyzed by using diffusion model. The longitudinal dispersion coefficient of solid particles and liquid based on actual mean slurry velocity, the mean settling velocity of solid particles, and the concentration of solid particles at the top of the column, respectively, were correlated with dimensionless groups. From these correlations empirical equations were obtained. The values of concentration of solid particles calculated from the empirical equations agreed with the observed values within ±20%.

The blending efficiencies of some impellers in batch mixing

Abstract: Mixing times for the blending of viscous liquids with tracer materials have been measured in a mechanically agitated tank using two conventional agitutor types (turbine, helical ribbon) and a series of novel tubular-type agitators. The range of conditions studied were: viscosity = 1 to 70,000 cP, agitator Reynolds number = 5 to 105, tank diameter = 11.5 in. It was found that in terms of agitator power requirement, the tubular agitators were generally more efficient for viscosities greater than 100cP than the others for the blending process. The effects of pseudoplastic non-Newtonian fluid behavior, of tank-baffles, and of tank size on mixing times have also been examined in several of the above cases.

On the dispersion of the sizes of droplets growing by condensation in turbulent clouds

Abstract: The effect of turbulence within a cloud on the distribution of the sizes of droplets growing by condensation has been examined in some detail with the aid of a scheme for simulating a fluctuating updraught numerically. It is found that, contrary to the conclusions previously reached by some Russian and Chinese workers, the spread in the radii of droplets at any given level which this mechanism produces is very small (generally < 0.2 γm). This result agrees with the conclusion of a similar analysis carried out by Warner. Other factors which may account for the observed distributions of droplet sizes have been considered and the most important appear to be mixing between a cloud and its environment and the variable composition of condensation nuclei. It also appears that the absorption of organic surface active substances on to some condensation nuclei probably accounts for the existence of small droplets in the interiors of well-developed clouds.

Self-balancing low temperature refrigeration system

Abstract: Extremely low temperatures, in the range of -40*F. to -300*F., are achieved in a single circuit compression refrigeration system which is capable of being operated by a conventional compressor without the aid of special start-up or stand-by equipment. The system relies upon a series of intermediate cooling stages in which each stage includes the steps of withdrawing a portion of the liquid condensate from a compressed vapor-liquid refrigerant mixture which enters that stage, throttling the withdrawn condensate to a lower pressure, mixing the throttled condensate with refrigerant being recycled to the compressor from the final evaporator and evaporating the throttled condensate to absorb heat from and at least partially condense the compressed unconcensed vapor in the compressed mixture.

Polyurethane polyelectrolytes and process for preparing same

Abstract: POLYURETHANES ARE PREPARED BY DISPERSING SOLID OR LIQUID POLYURETHANE POLYELECTROLYTES CONTAINING METHYLOL GROUPS BY MIXING WITH WATER, SUBJECTING THE ELECTROLYTES TO A HEAT TREATMENT OF 25 TO 200*C. AND REMOVING THE WATER.

Method of treating asphalt

Abstract: The method of treating asphalt by mixing without air-blowing a vacuum distilled asphalt and a mixture of phosphoric acids having an H3PO4 equivalent of greater than 100 percent concentration at elevated temperatures and the asphalt compositions thus prepared having significantly increased viscosity.

Combination of dilution chilling with scraped surface chilling in dewaxing lubricating oils

Abstract: Lubricating oil fractions are dewaxed by contacting them with successive increments of cold solvent at a plurality of points along a vertical tower while maintaining a zone of intense agitation at each point of solvent injection so that substantially instantaneous mixing occurs at each point, continuing the chilling by means of cold solvent injection until a temperature greater than the filtering temperature but less than about 35 DEG F. above the filtering temperature is reached and completing the cooling of the oil to the separation temperature in a scraped-surface cooler.

Process for the removal of sulfur dioxide from carrier gases

Abstract: A process is disclosed for the removal of sulfur dioxide from carrier gases formed in industrial processes such as as smelting, refining and power generating processes wherein the carrier gas is driven through an elongate mixing tube by means of a hot-water ejector drive in which finely atomized droplets of water in the form of a jet spray are intimately and turbulently mixed with the carrier gas in the mixing tube downstream of the hot-water ejector. An alkaline reagent is injected as a series of intense jets into the central portion of the jet spray emerging from the hot-water ejector and becomes intimately and turbulently mixed with the mixture of atomized droplets of water, steam and carrier gas which contains sulfur dioxide. The flow of the turbulent mixture through the mixing tube is regulated to provide retention time sufficient for the sulfur dioxide in the carrier gas to react with the alkaline reagent to form aqueous droplets of sulfur reaction products and for the droplets to grow to a size sufficient to permit removal by centrifugal means. In an alternative form of the invention, the carrier gases from which the sulfur dioxide has been substantially completely removed is further treated by driving the gases through a secondary mixing tube by means of a steam ejector and passing the turbulent mixture of gas, steam and water droplets through a condenser in which the condensible vapors are separated from the carrier gas. In the alternative form of the invention, alkaline reagents can be injected into the turbulent mixture contained in the secondary mixing tube to react with traces of sulfur dioxide or such odors and acidic gases as may then be present in the carrier gas.

Method of static mixing to produce metal foam

Abstract: Ingredients required to make metal foam having particulate members such as glass beads or steel wires embedded therein are mixed in a static mixer having no moving parts

Device and method for injecting liquids into a mixing head

Abstract: This invention relates to a device and a method for introducing and mixing a relatively small flow of a liquid possessing a low viscosity into a quantity of a liquid having a high viscosity, the action being turbulent with the introduction of a current of pressurized gas into said high viscosity liquid.

Mixing of molten plastic and gas

Abstract: Gas is injected into a flowing stream of molten plastic to provide a mixture containing an amount of gas which at ambient conditions would constitute about 10 percent to about 98 percent of the volume of the mixture. A relatively thin, large diameter annular stream of molten plastic advances through the mixing zone, the gas being injected into the mixture through at least one of the generally cylindrical walls of the mixing zone. Of particular importance, the gas is injected through a porous wall having more than a thousand openings per square centimeter, such as an ultra-fine sintered glass filter type of gas diffusion member. Each of the walls of the mixing zone is desirably tapered, so that the thickness of the molten cellular plastic effluent is greater than the thickness of the entering stream. The mixture advances through a length of mixing zone which is from about 10 to about 100 times the marginal increase in thickness of the stream. The effluent from the mixing zone flows through a heated stabilization zone which is several times longer than the mixing zone. The stabilized mixture can then be reshaped for flowing into streams utilizing the mixture of molten plastic and gas.

Process and apparatus for solids blending

Abstract: A process and apparatus for the blending of a bed of particulate solids operating cyclically by selectively regulated downward gravity flow of a fraction of the solids, fluidized mixing outside of the bed, followed by recycle to the top of the bed.

Mixing column for medical humidifier and method of humidifying inhalable gases

Abstract: A multi-stage sieve plate humidifier column with a series of plastic snap together modular mixing units that combine to form an elongated vertical column with interconnected mixing chambers. The column is confined inside a liquid supply bottle where it is submerged in a liquid used to humidify an inhalable gas such as oxygen or air. In a method of humidification, the gas is bubbled into a lower portion of the submerged column, transferred through the interconnecting chambers of the column where the bubbles are broken up and mixed with liquid, and then the humidified gas collected near a top of the column and conducted to a patient for inhalation.

Gas-abrasive mixing and feeding device

Abstract: An abrasive reservoir is provided with an internal venturi tube arranged to establish a recirculating stream of pressurized gas and abrasive. Provision is made for diverting a portion of the abrasive laden gas, with a controllable valve interposed in the delivery line.

Low modulus room temperature vulcanizable silicone elastomer

Abstract: A LOW MODULUS ROOM TEMPERATURE VULCANIZABLE SILICONE ELASTOMER IS OBTAINED BY MIXING 100 PARTS BY WEIGHT OF A HYDROXYL ENDBLOCKED POLYDIORGANOSILOXANE, 0 TO 150 PARTS BY WEIGHT OF A NON-ACIDIC, NON-REINFORCING FILLER, 2 TO 20 PARTS BY WEIGHT OF R-SI(-CH3)(-N(-R'')-CO-CH3)2 IN WHICH R IS METHYL, VINYL OR PHENYL AND R'' IS METHYL, ETHYL OR PHENYL AND 0.25 TO 7 PARTS BY WEIGHT OF AN AMINOXYSILICON COMPOUND HAVING 3 TO 10 AMINOXY GROUPS PER MOLECULE, THE LOW MODULUS SILICONE ELASTOMER IS USEFUL IN BUILDING CONSTRUCTION.

Method and apparatus for mixing liquids

Abstract: A method of rapidly mixing liquids which differ greatly from one another as regards their volume and/or density, to form emulsions or homogeneous mixtures One or more jets of the liquid dispersing agent are passed through nozzles at a velocity up to 100 m/s to an impulse exchange chamber, which is located in the liquid medium and extends in the downstream direction, together with the liquid to be dispersed, which latter liquid is ejected in the immediate proximity of the orifice of the nozzles providing the propulsive jet The average hydraulic diameter of the impulse exchange chamber is equal to from two to 20 times the diameter of that nozzle which is equal in cross-sectional area to all the nozzle orifices present, and its length is equal to from two to 30 times its hydraulic diameter

Swelling substance fixed to sheet - by first mixing it with thermoplastics powder then applying and heating

Abstract: A mixture of the swelling (turgescent) substance particles and thermoplastics (pref. H.P. polyethylene) particles which soften/melt at least 20 degrees C below the melting or decomposition temp. of the substance is applied to the surface; then it is heated with the surface to cause the thermoplastics to soften/melt.

Method for continuously manufacturing shaped gypsum articles

Abstract: A method for continuously manufacturing shaped gypsum articles which comprises mixing insoluble anhydrite with an accelerator for the setting, bentonite, methyl or ethyl alcohol and a proper amount of water, kneading the mixture to obtain a doughy paste, and extruding said paste continuously to manufacture shaped articles, followed by the setting thereof.

Method for producing a gradient elution

Abstract: The method of proportioning two liquids comprising periodically controlling the operation of a valving .[.means.]. .Iadd.arrangement .Iaddend.to control the amount of each liquid supplied to a mixing region during each period of valve operation to produce a supply of eluent having a precisely controlled time varying concentration of each liquid.

Process for mixing, kneading and granulating thermosetting plastic material in continuous operation

Abstract: A process for mixing, kneading and granulating thermosetting plastic material in continuous operation resides in first feeding the material through a first mixing zone of a screw extruder. While the material passes through this zone it is mixed,homogenized,and also partly condensed. Before the material reaches a second mixing zone in the extruder an agent adapted to interrupt the condensation reaction in the material and to reduce the viscosity thereof is fed into the extruder. This agent is intimately intermingled with the material as the same passes through the second mixing zone thereby interrupting the condensation reaction and reducing the viscosity of the material. After passing through the second zone, the material is extruded through a perforated discharge plate at the end of the extruder and finally granulated by suitable cutting means disposed directly adjacent to the exit side of the perforated plate.

Method for blending temperature sensitive ingredients in the production of dough

Abstract: Process for continuously blending temperature-sensitive ingredients, such as flour and shortening, in a mixing apparatus for the production of dough and simultaneously introducing into the dough mixture, a refrigerant or cooling medium which makes it possible to use a high proportion of shortening. The preferred cooling medium is carbon dioxide in the form of small solidified particles or snow which are introduced into the flour in the initial stages of the blending operation prior to combining of the chilled flour with the shortening. Preferably, the shortening is also subjected to a cooling operation prior to its introduction into the mixing apparatus.

Method and apparatus for mixing and transporting concrete

Abstract: A concrete mixing truck complying with maximum permissible highway legal load limitations, a trailer towed by the truck, and pneumatic conveyor means to transfer from the trailer to the truck separated, premeasured ingredients for one or more subsequently mixed concrete batches. The trailer may also separately store cement for admixture with the other ingredients of the first batch within the mixing truck when the hauling distance is such that the concrete mixing time specifications would be exceeded if all of the ingredients of the first batch were added to the truck at the concrete plant. When the separately stored ingredients in the trailer are pneumatically conveyed into the mixing truck, the entire void region in the mixer is completely filled with cement blown in under pressure so that the cement is more uniformly dispersed and in a much shorter time than customary with present in-field concrete mixing apparatus.

Method and apparatus for mixing solids and liquids

Abstract: A method and apparatus for mixing solid materials and liquids are provided. More specifically, such materials include particulate solids such as glass fibers and glass flakes, and foamable mixtures of two or more liquid components. The liquid components are first thoroughly mixed together before being mixed with the particulate solids. The mixed liquid is then supplied to a central zone and directed outwardly to the particulate solids in a zone surrounding the central one. After the solids and liquid are combined, this mixture is further mixed in a subsequent zone and then discharged to a location of use in a very short period of time, prior to the reaction and foaming of the liquid components.

Liquid-liquid extraction and plug-flow reactor apparatus

Abstract: LIQUID-LIQUID EXTRACTION AND PLUG-FLOW REACTOR APPARATUS COMPRISING A VERTICAL COLUMN HAVING A PLURALITY OF ALTORNATELY STATIONARY AND ROTATABLE PERFORATED PLATES OR DISKS IN SPACED RELATION. A COMPARATIVELY HEAVY LIQUID PHASE IS PASSED FROM THE TOP TO THE BOTTOM OF THE VERTICAL COLUMN AND A COMPARATIVELY LIGHT LIQUID PHASE IS PASSED FROM THE BOTTOM TO THE TOP OF THE COLUMN IN COUNTERCURRENT FLOW, DROPLETS ARE FORMED AS THE LIQUID PHASES PASS THROUGH THE PERFORATIONS. THE ROTATING PERFORATED PLATES ADVANTAGEOUSLY SHEAR THE DROPLETS TO FORM MANY NEW INTERFACIAL SURFACES. THE STATIONARY AND ROTATABLE PERFORATED PLATES BOTH EXTEND ACROSS ESSENTIALLY THE ENTIRE DIAMETER OF THE VERTICAL COLUMN SO THAT LIQUID IS FORCED TO PASS THROUGH APERTURES IN THE PLATES. ACCORDINGLY, BACKMIXING HAS BEEN FOUND TO BE SUBSTANTIALLY REDUCED AND SEPARATION EFFICIENTLY INCREASED. THE COMBINATION OF GOOD RADIAL MIXING AND LIMITED AXIAL OR BACKMIXING MAKES THE APPARATUS ESPECIALLY WELL-SUITED FOR USE AS A PLUG-FLOW REACTOR.

On a high viscosity polymer finisher apparatus with two agitator axes having multidisks

Abstract: The characteristics of a mixing apparatus with two agitator axes having multidisks as a high viscosity polymer finisher was studied from a practical point of view, 1) Holdup : it could be correlated by using a term of (μnD/δ). 2) Power consumption and mixing time : the results were compared with those of other high-viscosity equipment. 3) Residence time distribution and dead space : the former almost agreed with the tanks-inseries model. The latter seemed to be small. 4) Surface renewal action : the rate of surface renewal was determined from the gas absorption and also estimated by the observation of liquid flow. As a model reaction polycondensation polymerization of polyamide in the presence of water and viscosity stabilizer is discussed.

Spray mix applicator

Abstract: The spray mix applicator of the present invention is a device for mixing and spraying a mixture of two liquids at a prescribed flow rate in a prescribed proportion to each other, one liquid being under atmospheric pressure while the pressure of the other liquid may vary, for instance, from 15 pounds per square inch to 125 pounds per square inch without affecting the output of the device.

Method for producing mayonnaise

Abstract: A METHOD OF PRODUCING A HIGHLY STALE, NONPOURABLE MAYONNIASE OR MAYONNAISE-LIKE SALAD DRESSING WITH OR WITHOUT PREEMIXING WHICH COMPRISES SIMULTANEOUSLY INTRODUCING VEGETABLE OIL WATER, AN EGG YOLK CONTAINING INGREDIENT AND ACID INTO A SINGLE MIXING CHAMBER MIXING THE INGREDIENTS BY MEANS OF A HIGH SPEED IMPELLER TO IMPART HIFH SHEAR FORCES AND TO PROVIDE A STABLE EMULSION, AND CONTINUOUSLY REMOVING THE FINISHED PRODUCT FROM THE MIXING ZONE.