Automobile Absorption Conditioner

The purpose of this study is to develop a circuit for an automobile air conditioner, which will reduce the consumption of power developed by the engine. This paper proposes the design of an automobile absorption air conditioner. A description of the principle of operation of an automobile absorption air conditioner operating on a cycle of a one-stage absorption refrigeration machine has been given in the paper. It consists of a stripper (generator), a condenser, an absorber, an evaporator. Lithium bromide (LiBr) solution has been used as an absorbent, which has a low boiling point, is non-toxic and safe. 3D-models of the absorber and generator of an automobile absorption air conditioner has been developed in the course of the research. The absorber is designed to form a weak absorbent solution. This solution is supplied to the generator heat exchanger using a liquid pump. There it is heated by the exhaust gases to the boiling point. The solution evaporates and water vapor enters the condenser (evaporator). In the generator, the solution is concentrated from 52 to 60 %. After that, water vapor is supplied to the absorber from the condenser, and a concentrated absorbent solution is supplied from the generator. It should be noted that the generator is a key element of an automobile absorption air conditioning system. Inside it is a strong LiBr solution that feeds the absorber. The design of the air conditioning system does not provide for the use of a compressor and allows to reduce the power loss of the power plant to the drive of the liquid pump. According to calculations, the pump drive power was 0.17 kW. For comparison, the compressor of a modern car air conditioner consumes 7–11 kW. An absorption car air conditioner provides the following advantages: additional engine cooling, environmental friendliness, fuel economy, efficient use of the heat of vehicle exhaust gases. A distinctive feature of this design is that it is proposed to use the heat of the exhaust gases for the process of heating the absorbent. This design can fully compete with the existing modern car air conditioners.

Combination of ozonation and absorption through membrane contactor to remove ammonia from waste water

Ammonia in waste water is a major pollutant produced in industrial and agricultural waste water. Ammonia is often removed by conventional technologies such as pack tower aeration, biological treatment or adsorption as ammonium ion onto zeolites. In many cases, conventional methods are very costly and inefficient, and therefore, there is a need for an alternative separation technique for more efficient removal of ammonia from waste waters. The aim of this study is to investigate the performance of the combination of ozonation and absorption through membrane processes to remove ammonia from wastewater using natural hot spring water (NHSW) as absorbent. Experimental results show that operating variables such as time and pH of absorbent solution are found to remarkably influence the removal process efficiency. Based on experimental results ozonation can improve ammonia removal efficiency through the hollow fiber membrane contactor. Ammonia removal efficiencies and overall mass transfer coefficients increase with decreasing pH of absorbent solution. Keywords: ammonia, mass transfer, membrane, ozonation, removal efficiencyAbstrak Amonia di dalam air limbah merupakan polutan utama yang berasal dari air limbah industri dan pertanian. Amonia kebanyak disisihkan dengan teknologi konvensional seperti aerasi di menara isian, pengolahan secara biologi atau penyerapan sebagai ion amonium pada zeolit. Dalam banyak hal, metode konvensional sangat mahal dan kurang efisien, sehingga diperlukan teknik separasi alternatif untuk proses penyisihan amonia dari air limbah yang lebih efisien. Tujuan dari studi ini adalah untuk menyelidiki kinerja kombinasi proses ozonasi dan proses absorbsi melalui membran untuk menyisihkan amonia dari air limbah menggunakan absorben berbahan dasar air dari sumber air panas. Hasil eksperimen memperlihatkan bahwa variabel operasi, seperti waktu dan pH larutan penyerap, sangat mempengaruhi efisiensi proses penyisihan amonia. Berdasarkan hasil eksperimen, ozonasi dapat meningkatkan efisiensi penyisihan ammonia melalui kontaktor membran serat berlubang. Efisiensi penyisihan amonia dan koefisien perpindahan massa keseluruhan naik dengan turunnya pH larutan penyerap.Kata kunci: amonia, perpindahan massa, membran, ozonasi, efisiensi penyisihan

Thermal Desorption of Iodine-123 from Tellurium-122 Oxide Irradiated by Deuterons

The paper studies the iodine-123 extraction process from the targets of enriched Tellurium-122 irradiated by deuterons at the cyclotron R-7M. We researched the regularities of radionuclide accumulation in the absorbent solution tank, depending on the temperature and air pumping regime through the system. As a result, we suggested a separate temperature treatment of the targets with the purpose of their preliminary purification from impurities and subsequent obtaining of "Na123I" preparation with radiochemical yield 97%.

THE INFLUENCE OF ABSORBENT SOLUTION ON THE EFFECTIVENESS OF PASSIVE DIFFUSIVE SAMPLERS

The method of applying passive diffusive samplers for research on air quality is simple, easy enough and requires no electricity. The operating principle of almost all passive samplers is based on chemical reactions taking place on absorbent (impregnated filter or grid). The pollutant absorption mechanism is based on passive diffusion through the gas diffusion layer to absorbent. The diffusion process can be explained by first Fick’s law described as a free movement of gases from the ambient air to a passive sampler. This movement depends on pollutant gradient. The aim of this paper is to analyse the influence of an impregnating solution on the efficiency of diffusive samplers. The object of the study covers the triethanolamine (TEA) aqueous solutions of 5%, 10%, 20%, 30% and 50%. The results obtained showed that 30% and 50% aqueous solution gave 68% and 89% relative error making the true meaning of the oxides of nitrogen analyzer testimony. Data on the passive samplers impregnated with TEA aqueous solutions having concentrations of 5%, 10% and 20% are within definite 25% uncertainty established by the European Union Directives.

Thermal Performance Predictions and Sensitivity Analysis for a Parallel Flow Solar Regenerator

One of the efficient methods of regenerating the weak absorbent solution using solar energy is the forced flow regeneration system. This paper describes a forced flow solar regenerator in which the absorbent solution to be concentrated flows as a thin film over the absorber and the water evaporating from the solution due to absorption of solar energy is removed by forced air stream, which flow parallel to the liquid film. A theoretical model, which includes the variation of rate of evaporation of water along the flow length of the regenerator, has been used to examine the thermal performance of the regenerator. Changes in thermal performance are reported in terms of the ratio of solution flow rate to air flow rate and the amount of water evaporated from the absorbent solution.