The paper discusses a hollow sprayer scrubber and cooler involving complete evaporation of the irrigating liquid. It is shown to be possible to use an empirical model to calculate the geometrical parameters. Technical characteristics are given of a standard series of scrubbers of SOI type with complete evaporation of irrigating liquid.Calculations have been performed [1, 2] on the evaporation time for a polydisperse flow of droplets (diameter of the large droplets d d , mass proportion not more than 10%, equal to 553 µm) in a hollow scrubber based on three mathematical models (empirical, iterative, and simplified), and values have been obtained for the necessary active height * (Table 1) in relation to the initial parameters of the evaporative cooling, gas temperature at the inlet to the apparatus 750°C, at the outlet 400°C, mean gas speed in apparatus 4.5 m/sec, and initial water content 0.35 kg/kg of dry gas.We consider the evaporative cooling in a standard scrubber (Fig. 1), in which there are mechanical sprayers of centrifugal type (nozzle diameter 4 mm) working at a pressure of 0.68 ± 0.01 MPa. For these devices at this pressure, the diameter of the large droplets constituted by mass not more than 10%, is 314 µm, i.e., almost half of that assumed in calculations in [1,2]. Use has been made in [1, 2] of calculation models, and the height of a scrubber has been determined required to provide complete evaporation, and the evaporation time.The calculations have been performed for the air-water system with the following initial parameters: gas temperature at the inlet 750°C, and that at the outlet 400°C; mean gas speed in apparatus 4.5 m/sec; initial water content 0.35 kg/kg of dry gases; and initial temperature of irrigating liquid (water) 20°C. Table 2 gives the results.Calculations from the iterative model (Fig. 2) show that as the size of the large droplets is reduced from 553 to 314 µm, the time needed for the droplets to attain the floating velocity is approximately 0.1 sec, which is much less than was obtained in [1, 2] (about 0.4 sec). In the standard apparatus, the smaller droplet diameter means that the evaporation is much more rapid.At the same time, the practical data were analyzed, ** which had been obtained on testing a plant for destruction of wastes by incineration, in which the hollow scrubber (Fig. 3) was installed before the sleeve filter.The water pressure ahead of the sprayers was up to 2.5 MPa, and the size of the mass-largest drops (10%) was approximately 151 µm.

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A standard series of rapid hollow absorbers with an output ranging from 5000 to 65000 m 3 /h of cleaned gases is developed. The absorbers are intended for readily soluble gases (HCl, HF, SO 2 , etc.). The series includes five standard sizes of scrubbers 600, 900, 1200, 1600, and 2000 mm in diameter. Technical data are presented for the scrubbers.The MGUIE has developed a detailed design for a standard-size series of rapid hollow absorbers with an output of cleaned gases ranging from 5000 to 65000 m 3 /h. The vessels comprising this series are intended for the absorption of readily soluble gases (HCl, HF, SO 2 , etc.). The series includes five standard sizes of scrubbers 600, 900, 1200, 1600, and 2000 mm in diameter. The average velocity of the gases in the free section of a vessel is 5.5 m/sec, and the reflux density is 35-55 m 3 /(m 2 ·h). Three tiers of mechanical injectors (three in each tier) are established within the absorbers.The absorber ( Fig. 1) with a diameter D consists of a cylindrical hollow metallic housing with a conical bottom, lower intake pipe for waste gases, an outlet pipe for the cleaned gases, and three reflux collectors.The collector, which is intended for uniform distribution and feed of absorbent to the injectors, is mounted external to the absorber -above the injectors to eliminate the formation of stagnant zones when the feed of absorbent is curtailed.The liquid is atomized by mechanical centrifugal-jet injectors (Fig. 2) with a spray-cone angle of 120°(d n is the diameter of the nozzle). Nine injectors are established in the vessel. The spray cone of the injectors in the lower tier is directed upward (along the path of the gas), while those in the upper and middle tiers are directed downward; this ensures optimal contact conditions between the gases being cleaned and the irrigating liquid. The distance between tiers is 2.5 m.The number of injectors in a tier, and their arrangement are selected from the condition whereby the section of the absorber is covered by cone sprays for the assigned reflux densities. The injectors in each tier are shifted 40°with respect to another tier for complete coverage of the free section of the absorber by the liquid spray.Injectors with nozzles ranging from 6 to 22 mm in diameter are mounted as a function of the required flow rate of absorbent. The pressure of the liquid supplied for the spray can be varied in cases when it is required to adjust the flow rate of absorbent.Since the absorbers operate at high gas-flow velocities, and the average drop size in the injectors employed under an atomizing pressure of 0.2 MPa, which is calculated in accordance with the procedure proposed in [1], ranges from 370 to 810 µm, rather vigorous splashing and carry-off take place during their operation. According to Prikhod'ko [2], splash and carry-off amount to 177-304 liters/m 3 when the reflux density is 35-55 m 3 /(m 2 ·h), and the velocity of the gas flow is 5.5 m/sec. In the upper section of the vessels, therefore, it is necessary to mount a TsKKZ type of centrifu...

The majority of moist dust and gas collectors are furnished with a different type of sprinkler intended for the delivery of water, solutions, or suspensions to an apparatus. As operating practice indicates, it is necessary to sprinkle the active crosssectional area of the collectors to achieve maximum efficiency of the collection process; this is rather difficult, especially in cases where the volumes of purified gas reach tens, and occasionally even hundreds of thousands of cubic meters per hour.Centrifugal and splash-plate spray injectors, which form a spray in the form of a hollow cone are used most frequently in gas-cleaning equipment. Existing centrifugal spray injectors are characterized by the existence of two flows into which the delivered liquid is divided; a peripheral flow imparts rotation, and a second flow is delivered into the mixing chamber in the form of an axial jet. The rotating flow transmits some of the energy of the central jet and partially untwists it, and is itself slowed somewhat. The single resultant flow that forms breaks down beyond the limits of the nozzle channel with the formation of a flare in the form of a filled cone.This type of injectors ensures uniform spraying of the section of gas cleaners. They are widely used to atomize pure water and solutions, but clog rapidly when installed in a circulating water-supply system and when suspensions are delivered.To improve the operational reliability of a centrifugal spray injector intended for coarse atomization of suspensions containing up to 2-3 g/liter of suspended matter, and water circulating in a circulating water-supply system, the ScientificResearch Institute of Gas Purification for Industry and Sanitation has developed a centrifugal spray injector for coarse atomization (Fig. 1).The injector developed is distinguished by a vortex-generator cover angle that has been reduced to I 1 ~ The vortex generator is simple to fabricate, and can be made by stamping for series production. This makes it possible to operate on suspensions and clarified water containing suspended particles up to 15-20 mm in diameter, and also fibrous inclusions. The coefficient of flow/z = 0.75 for the injector. The cover angle of the flare is -50 ~ The average range of the flare is 4.5-6 m. Calculations indicate that the range should increase to 7-8 m when the productivity of the injector is increased to 120 n~/h.A nomogram for selection of the type size of injector as a function of productivity is presented in Fig. 2. The centrifugal spray injector was developed for a spray feed in scrubbers used for the desulfuration of flue gases by the limestone method, and uniform distribution of a spraying liquid throughout the tube plate of a battery emulsifier with a 2000 • 2000-mm section, which is intended for installation at thermal power plants.To estimate the integral size distribution of drops of atomized liquid and the uniformity of its distribution throughout the effective section, we used an injector with an efflux diameter of 15 ram.The experimental assessme...