Designs of drop-film sprinklers based on cellular polymeric shells formed by a layer of intersecting cylindrical (or other shape) polymeric fibers are described. The dependence of the evaporation number on the relative flow rate of air is investigated for the designs presented. An empirical relationship is derived for calculation of the pressure drop in the cooling-tower sprinkler, which permits most accurate determination of the load on the fan and the optimal operating conditions of the cooling tower.The temperature regime of any production process is ensured by the use of circulating water-supply systems normally equipped with mechanical-draft and chimney-type cooling towers.Closed autonomous water-supply systems [1], which provide for delivery of water to a production process with the required volumes and appropriate quality, function for the purpose of rational utilization of water resources at industrial establishments, since water cooling is currently most economically expedient for basic and auxiliary equipment.Industrial water-supply systems consist of a set of interrelated structures -water intakes, pumping plants, and installations to clean and improve the quality of the water, which regulate both the reserve tanks, water coolers, and distributing network of pipelines. Some of the enumerated structures cannot be used in the water-supply systems, depending on the purpose and local conditions [2].The circulating water that passes through the production cycle is cooled to the required temperature in chimney-type or mechanical-draft cooling towers. The requirements set forth for the temperature of the circulating water by various industrial establishments depend on the production process and operating properties of the equipment. A temperature in excess of that regulated for the circulating water will lead to reduction in output of production and degradation of its quality.The effectiveness of the water-cooling process in cooling towers is determined by structural characteristics of the packings (sprinklers), which ensure the required surface area of phase contact with minimal aero-and hydrodynamic resistances.Despite a wide variety of sprinkler designs for cooling towers, the need currently arises for the development of new highly effective designs adapted to manufacture, which are formed from polymeric materials, since a trend toward an increase in output of articles formed from these materials with different dimensions and cross-sectional shapes is observed in industry.The sprinklers may be film or drop-film, depending on the character of the dominant cooling surface. Different types of sprinklers may also have extremely different designs of individual components and dimensions.Results of analysis of familiar structures are used in developing new sprinkler designs for cooling towers. Let us examine the operating principles of the sprinklers and their structural characteristics. In each specific case, the sprinklers should correspond to technical requirements established by government standards with resp...

The design of an atmospheric film-type sprayer, which is one of the basic components of cooling towers serving as component parts of the system supplying circulating water for any production process, is described. Promising use of the sprayer design developed for cooling towers in the chemical and petrochemical branches of industry is indicated.Cooling of basic and auxiliary production equipment at establishments within the chemical and petrochemical branches of industry is normally accomplished with use of reservoirs -coolers, spray ponds, and evaporative cooling towers. During optimal operation, these systems enable a continuous production process with high technico-economic indicators.Open systems of circulating water supply with air cooling in towers, which offer a number of significant advantages over other systems and which permit the following, have come into the most widespread use in practical industrial water supply:• rational utilization of water resources and lowering of the intake of water from natural sources to a minimum; this assumes vast significance in connection with the water deficit characteristic of many industrial regions; and • lowering to a minimum, or elimination of the water released to water-supply sources, and, consequently, less contamination of the latter [1]. In the majority of cases, the cooling efficiency of production equipment is determined by the packings (sprayers), which are capable of ensuring the required surface area of phase contact with minimum possible aero-and hydrodynamic resistances.At the present time, designs fabricated from wood or asbestos cement are used in industry as sprayers for cooling towers. Basic disadvantages of these sprayers are the heavy weight that is introduced per unit area, small surface area of phase contact, high aerodynamic-resistance factor, and short service life. Moreover, wood is sensitive to chemical and biological effects, and the slats of the sprayers cannot be less than 10 mm thick due to warping and failure of the wood as a result of lignin being flushed from the latter (delignification) by the water. Only cellulose remains in the wood, as a result of which it is weakened. The delignification process proceeds more vigorously at a high pH and with a significant content of active chlorine in the water [2]. When the pH is increased from 5 to 9, therefore, the failure rate of larch and oak wood increases by a factor of 2-3, and that of pine and spruce by factors of 10-16 [1].When polymeric materials that appreciably surpass wood and asbestos cement in terms of production characteristics are used for the development of sprayer designs, the possibility of creating a new generation of sprayers with improved characteristics arises.

It is noted that in virtually all establishments of the gas and petrochemical industry, basic and auxiliary production equipment is cooled by a circulating water-supply system equipped with cooling towers. Here, the working tower releases air saturated with water vapor to the atmosphere, and the establishment must maintain the water-circulating systems from natural sources. A water-trap design for cooling towers, the use of which will make it possible to reduce appreciably the moisture content in the vapor-gas flow released by the tower, is described.The water resources of Russia are a national treasure, and not only the level of economic development of the country, but also the health of the people depend on their condition. In this connection, the problem of rational utilization and protection of surface water from contamination and depletion requires serious attention [1].Autonomous closed water-supply systems function for the purpose of rational utilization of water resources at industrial establishments. Water cooling of basic and auxiliary equipment is currently most economically expedient. In turn, the circulating water that passes through a production cycle is cooled to the required temperatures in air-cooled vessels, chimney-type cooling towers, and mechanical draft towers.One of the negative factors in the operation of cooling towers is the carry-off of drops of circulating water in which various chemical compounds are found, for example, heavy-metal ions, detergents, pesticides, biogenic elements, toxic chemical compounds, phenols, petroleum products, and chlorine-based organic compounds. The amount of atmospheric carry-off from cooling towers is regulated by the Construction Rules and Regulations, and is defined as the water lost due to carry-off by the wind (in chimney-type cooling towers), and a fan-blown discharge of air (in mechanical-draft towers).The amount of carry-off allowed by the Construction Rules and Regulations depends on the type of coolant and the harmfulness (toxicity) of the water. It ranges from 0.05 to 0.20% for cooling towers with water traps, and from 0.5 to 1.0% for chimney-type cooling towers without water traps [2]. Even at chemical plants, however, mechanical-draft towers are not often equipped with water traps, and the slightly effective designs currently installed fail to meet modern ecological requirements. As a result, drop carry-off amounts to 5-7%; this results in appreciable degradation of the ecological situation in the industrial regions and areas within their immediate vicinity. Here, feed maintenance of the circulating-water system is increased by fresh water from natural sources.

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Industrial procedures for the production of alkylate are associated with use of dangerous and toxic liquid catalysts. Developments are being made worldwide to convert the alkylation process to solid-acid catalysts. These catalysts are characterized, however, by a short service life. The potential for improvement in the operational properties of solid-acid catalysts by the introduction of small amounts of promoters to the reaction is examined.Throughout the world, the portion of alkylate in the overall consumption of components has reached 25% in automotive gasolines, and more than 60% in aviation gasolines. The volume of alkylate production exceeds 70 million tons/year abroad, and a total of 0.5 million tons/year in Russia. According to forecasts for the next several years, use of alkylate in the United States will double [1].The operational and ecological properties of alkylate satisfy requirements set forth in modern European and American standards for fuel utilized by automotive internal-combustion engines. Industrial procedures for its production are associated with use of such dangerous and toxic liquid catalysts as sulfuric or hydrofluoric acid, requiring use of equipment for neutralization of the acid, vessels for washing of the product, and tanks for storage of the fresh and spent acid. Hydrofluoric acid is again more dangerous by the fact that it is capable of forming stable aerosols during an emergency leakage. In this connection, the development of an alkylation procedure using catalysts devoid of deficiencies inherent to liquid acid catalysts is one of the promising problems. Some of these catalysts may become new heterogeneous catalysts that are developed on a zeolite base. Manifesting high selectivity, activity, stability, and capability of regeneration, which are required for successful alkylation [2], zeolites ensure the production of high-quality alkylate.Type NaY zeolites are inactive in the alkylation process. Only essentially complete ion exchange of Na + ions for NH 4 + , Ca 2+ , and RZ 3+ cations with intermediate stages of calcination at 570-600°C merely results in their manifestation of Lewis and Bronsted acid centers, which are required for the formation of

The systems of reverse water supply are one of the most important elements of a technological complex of the enterprises of many industries: chemical, oil processing, petrochemical, machine building, metallurgical, etc. Productivity of processing equipment, quality and prime cost of a product, a specific consumption of raw materials and the electric power depend on quality and overall performance of systems of reverse water supply. Temperature conditions of any production are observed by means of recirculated water supply systems, which are most often equipped with fan and tower cooling towers. This article describes the design of drip-film sprinklers, which are one of the main components of the cooling tower.

From all variety of instrument registration of processes of hashing for an intensification of chemical and technological processes in the industry small-volume rotor mixers and dispersers with disk actions even more often find application. In this article the design of the small-volume mixer for receiving heterogeneous mixes is described. Constructive design of the device allows to carry out efficiently processing of homogeneous and heterogeneous mixtures.