Liquid Ring Vacuum Pumps for Heat and Mass Transfer Processes

The paper examines the calculation of a liquid ring vacuum pump, using the example of the drying process of various materials. It was found that for two-stage convective vacuum-impulse drying it is economically efficient to use a two-stage liquid ring vacuum pump with the ability to turn off the second stage. A method for calculating the specific power of one-stage and two-stage liquid ring vacuum pumps, taking into account heat and mass transfer and thermal processes that occur during operation is proposed.

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Prospects of using a liquid ring vacuum pump with automatic adjustable discharge window when grinding grape seeds and pomace

Magarach. Vinogradstvo i Vinodelie ◽

10.35547/im.2021.50.40.009 ◽

2021 ◽

pp. 55-60

Author(s):

Юрий Юрьевич Родионов ◽

Анастасия Игоревна Скоморохова ◽

Юрий Викторович Родионов ◽

Дмитрий Вячеславович Никитин ◽

Сергей Иванович Данилин ◽

...

Keyword(s):

Vacuum Pump ◽

Grape Pomace ◽

Biologically Active ◽

Specific Power ◽

Industrial Complex ◽

Grape Seeds ◽

Two Stage ◽

Plant Products ◽

Plant Powders ◽

Liquid Ring

Для повышения сохранения биологически активных веществ, уменьшения энергопотребления в процессе измельчения и получения порошка заданной степени помола из виноградных выжимок и семян предлагается использование установки двухступенчатой дисково-шаровой вакуумной мельницы. Предложенная конструкция двухступенчатой мельницы оказывает влияние на безопасность работы (исключаются взрывы) и экологичность (не создает запыленности окружающей среды). В конструкции разработанной установки важным объектом является вакуумный насос. Приведены устройство и основные принципы работы классического одноступенчатого водокольцевого вакуумного насоса производства ОАО «БЕСКОМ» и жидкостно-кольцевого вакуумного насоса с возможностью автоматического регулирования размеров нагнетательного окна, разработанного в ФГБОУ ВО «ТГТУ» на кафедре «МИГ». Показаны основные преимущества предлагаемого насоса по сравнению с классическим вариантом. На основе испытаний был проведен сравнительный анализ разработанного жидкостно-кольцевого вакуумного насоса с автоматическим регулируемым размером нагнетательного окна и классического вакуумного насоса равной быстроты действия, результаты которого продемонстрировали существенную эффективность использования первой машины. Установлено, что затраты удельной мощности в процессе транспортирования растительных порошков на 20-25% ниже при равной быстроте действия. Экономический расчет демонстрирует эффективность применения новой конструкции разработанного вакуумного насоса в технологическом процессе тонкого измельчения сухих растительных продуктов за счет вакуумного отвода заданной фракции помола. Поэтому разработанный насос рекомендуется использовать для измельчения сухих сыпучих растительных продуктов на крупных перерабатывающих предприятиях агропромышленного комплекса, пищевой, фармацевтической и парфюмерной отраслях промышленности. To increase the preservation of biologically active substances, reduce energy consumption in the grinding process and obtain a powder of a given degree of grinding from grape pomace and seeds, it is proposed to use a two-stage disk-ball vacuum mill. The proposed design of a two-stage mill affects the safety of work (excluding explosions) and environmental friendliness (does not create a dusty environment). An important object in the design of the developed installation is the vacuum pump. The device and basic principles of operation of a classic single-stage liquid ring vacuum pump manufactured by JSC "BESCOM" and a liquid ring vacuum pump with the ability to automatically adjust the size of the discharge window, developed at the TSTU Department of MIG are presented. The main advantages of the proposed pump in comparison with the classic version are shown.Based on the tests, a comparative analysis of the developed liquid ring vacuum pump with an automatically adjustable discharge window size and a classical vacuum pump of equal action speed was carried out, the results of which demonstrated the significant efficiency of using the first machine. It has been established that the specific power consumption in the process of transporting plant powders is 20-25% lower with the same speed of action. An economic calculation demonstrates the effectiveness of using a new design of the developed vacuum pump in the technological process of fine grinding of dry plant products due to the vacuum removal of a given grinding fraction. Therefore, the developed pump is recommended to be used for grinding dry bulk plant products at large processing enterprises of the agro-industrial complex, food, pharmaceutical and perfumery industries.

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Numerical modeling of energy efficient solutions of foundry class electric arc furnaces.

Journal of Electrical and power engineering ◽

10.31474/2074-2630-2020-2-77-86 ◽

2020 ◽

Vol 23 (2) ◽

pp. 77-86

Author(s):

S. TIMOSHENKO ◽

◽

E. NIEMTSEV ◽

Keyword(s):

Mass Transfer ◽

Numerical Modeling ◽

Heat And Mass Transfer ◽

Heat Loss ◽

Basic Unit ◽

Specific Power ◽

Water Cooling ◽

Transfer Processes ◽

Arc Furnaces ◽

Mass Transfer Processes

Research is aimed at reducing the energy loss of foundry class arc furnace, which belongs to energy-consuming units with a non-rhythmic work schedule, and characterizes by low energy efficiency. Method of numerical modeling substantiates the concept of furnace modernization, which consists in rising the specific electric power by lowering the capacity at constant productivity, relative increasing of the liquid bath depth, reducing accumulation heat loss by refractory lining through introduction of energy saving water-cooled elements with a spatial structure in its local areas and intensification of heat and mass transfer processes in the "deep" bath with pneumatic stirring. It is determined that for arc furnaces with capacity of 12 and 6 tons, working in one shift, it is rational to reduce the capacity to 6 and 3 tons respectively and the bath shape factor (ratio of diameter to depth) from 5 to 2.5; installation of water-cooled elements in central endurance critical part of the roof and upper parts of the walls with coverage of 0.20-0.32 and 0.5-0.8 of working surface, respectively. With regard to the economy of heating systems, the expansion of the cooling system for the economic efficiency of modernization is 12 tons of chipboard with magnesite lining, so in the small world, dinas lining. For 6 t furnaces of water-cooling elements at the same time the magnesite lining is also effective, the protector is more cheap acidic lining (dinas), however, the water-cooling elements require a larger analogue. With available supply transformer, the specific power increases to 1 MVA/t, which will allow, due to intensification of heat and mass transfer processes, provide quantitative and qualitative indicators of production with lower, compared to the basic unit, heat loss. The implementation of proposed solutions will reduce energy consumption by 75 kWh/t and, taking into account the cost of refractory, provide an economic effect of 320-515 UAH/t.

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