Power solids mixing

Hexamethylenetetramine Explosive. A powerful solid explosive was claimed to have been prepd by oxidizing hexamine with a solution of hydrogen peroxide, treating the resulting product with nitric acid and then, reoxidizing with H202 (Ref 1). After drying, this was mixed with AN, castor oil and turpentine (Ref 2)... 

The hydrodynamic parameters that are required for stirred tank design and analysis include phase holdups (gas, liquid, and solid) volumetric gas-liquid mass-transfer coefficient liquid-solid mass-transfer coefficient liquid, gas, and solid mixing and heat-transfer coefficients. The hydrodynamics are driven primarily by the stirrer power input and the stirrer geometry/type, and not by the gas flow. Hence, additional parameters include the power input of the stirrer and the pumping flow rate of the stirrer. 

The one phase of solids mixing which has been treated at length in the literature is the description of equipment. In textbooks, reference books, and review articles, pictures of equipment are shown and tables or charts given, which list suitable equipment for various applications. Also, details of machines, diagrams of their shapes, and practical construction data are available, including approximate power requirements. 

Several criteria have been used in various studies to judge the performance of dry solids mixing equipment a. the uniformity of the batch with regard to either composition or some other property, b. the time required to achieve a certain uniformity, and c. the power required to mix the batch to a certain degree of uniformity. Most studies have dealt with either a. or b. Complete quantitative performance criteria should cover all three of these aspects. 

L. T. Fan et al.. Powder Technology, 68, 195-196 (1991)]. However, Egermann [L. T. Fan, Y. Chen, and F. S. Lai, Recent Developments in Solids Mixing, Powder Technology 61, 255-287 (1990)] points to the fact that one should only use ordered mixing to describe the condition and not the mixing of fine particles using powerful interparticle forces. 

Masiuk, S. (1987). Power consumption, mixing time and attrition action for solids mixing in a ribbon mixCT, Powder Technol, 51, 217-229. 

Fig. 1 shows the block diagram of the vibrometer, in which the most sensible to small phase variations interferometric scheme is employed. It consists of the microwave and the display units. The display unit consists of the power supply 1, controller 2 of the phase modulator 3, microprocessor unit 9 and low-frequency amplifier 10. The microwave unit contains the electromechanical phase modulator 3, a solid-state microwave oscillator 4, an attenuator 5, a bidirectional coupler 6, a horn antenna 7 and a microwave detector 11. The horn antenna is used for transmitting the microwave and receiving the reflected signal, which is mixed with the reference signal in the bidirectional coupler. In the reference channel the electromechanical phase modulator is used to provide automatic calibration of the instrument. To adjust the antenna beam to the object under test, the microwave unit is placed on the platform which can be shifted in vertical and horizontal planes. 

Kneading Devices These are closely related to the agitated pan but differ as being primarily mixing devices with heat transfer a secondary consideration. Heat transfer is provided by jacketed construction of the main body and is effected by a coolant, hot water, or steam. These devices are applicable for the compounding of divided solids by mechanical rather than chemical action. Apphcation is largely in the pharmaceutical and food-processing industries. For a more complete description, illustrations, performance, and power requirements, refer to Sec. 19. 

Another phenomenon is the increase in power required with percent sohds, which makes a dramatic change at approximately 40 percent by volume, and then dramatically changes again as we approach the ultimate weight percent of settled solids. This phenomenon is covered by Oldshue (op. cit.), who describes conditions required for mixing slurries in the 80 to 100 percent range of the ultimate weight percent of settled sohds. 

With any chemical treatment system, the main task is one of getting the chemical thoroughly mixed with the solids without degrading the floes which are formed. For those slurries that are relatively fluid, the chemical can frequently be added and mixed satisfactorily using a relatively wide spatula. However, for those thick, relatively viscous slurries, a power mixer will be required. In this case, the mixer should be stopped about one second after the last of the flocculant is added. Should this approach be required, it means that a suitably designed addition system must be supplied with the full-scale instaUation in order to do an effective job of flocculation. 

Gemini North Observatory/CTI Mode-locked SFG Laser. CTT is developing the first commercial solid-state Na LGS system. It will be installed on the center section of the 8-m Gemini North telescope, with the output beam relayed to a projector behind the secondary mirror. The projected beam is required to be 10-20 W power, with M2 < 1.5. The architecture is based on sum-frequency mixing two mode-locked solid-state Nd YAG lasers. The mode-locked format provides significantly higher peak intensity than CW, enabling more efficient SFG conversion. The laser is also free of the thermal and intensity transients that are inherent in the macro pulse format. The chosen... 

Mixed plastics waste appears to be well suited for use in energy recovery, either as a co-eombustion fuel in a power plant designed for solid fuels, or as the sole fuel in speeially designed plants. This paper reports test results on the co-combustion of mixed household plasties with eoal. The tests were performed in a bubbling fluidised bed low-pressure steam boiler. The results show that both inorganic and organic total specific emissions were lower for mixed household plasties than for coal. Tabulated data are presented. 3 refs. 

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