Performance of an Absorber With Hydrophobic Membrane Contactor at Aqueous Solution-Water Vapor Interface

2010 ◽  
Vol 2 (3) ◽  
Author(s):  
Ahmed Hamza H. Ali
Keyword(s):  
Aqueous Solution ◽  
Water Vapor ◽  
Water Temperature ◽  
Cooling Water ◽  
Cooling Capacity ◽  
Hot Water ◽  
Membrane Contactor ◽  
Water Coolant ◽  
Hydrophobic Membrane ◽  
Vapor Interface

In this study, a detailed modeling of the heat and mass transfer processes inside a plate-and-frame absorber with hydrophobic microporous membrane contactor at aqueous solution-water vapor interface as a part of a chiller model is developed. The absorber is a component of a 5 kW cooling capacity single effect lithium bromide-water absorption chiller with a hot water thermally driven generator, a water-cooled absorber, and a condenser. The model is used to investigate the performance of the absorber in case the chiller operates at different values of the inlet driving hot water and cooling water (coolant) temperatures. The results clearly indicate that for the same cooling capacity of the chiller and compared with the performance at the design point value, increasing the inlet driving hot water temperature results in an increase in the required absorber size and consequently a decrease in the absorber performance, while decreasing the cooling water (coolant) inlet temperature leads to slight decreases in the required absorber size and consequently an increase in the absorber performance. The effect is prominent and can be used to decrease the absorber size for chillers work in places where the option of lower inlet coolant temperature is available with normal driving hot water temperature.

Performance of an Absorber With Hydrophobic Membrane Contactor at Aqueous Solution-Water Vapor Interface

2009 ◽  
Author(s):  
Ahmed Hamza H. Ali ◽  
Mahmoud Ahmed
Keyword(s):  
Aqueous Solution ◽  
Water Vapor ◽  
Lithium Bromide ◽  
Cooling Water ◽  
Hot Water ◽  
Inlet Temperature ◽  
Membrane Contactor ◽  
Water Coolant ◽  
Hydrophobic Membrane ◽  
Vapor Interface

In this study, analytical investigation at off-design conditions on performance of a plates-and-frames absorber with hydrophobic microporous membrane contactor at aqueous solution-water vapor interface are carried out. The absorber is a component of a single-effect lithium bromide-water absorption chiller with a hot water thermally driven generator and water-cooled absorber and condenser. Integrating the absorber model with the chiller model is used to evaluate the absorber performance at off-design conditions corresponding to different inlet both driving hot water and cooling water (coolant) temperatures. For the same cooling capacity of the chiller and referring to design point values, the results indicate that, increasing the inlet driving hot water temperature results in an increase in the required absorber size, consequently, a decrease in the absorber performance. While, decreasing the cooling water (coolant) inlet temperature leads to slightly decreases in the required absorber size, consequently, an increase in the absorber performance.

Design and Modeling of One Refrigeration Ton Solar Assisted Adsorption Air Conditioning System

2014 ◽  
Vol 137 (1) ◽  
Author(s):  
M. Alkhair ◽  
M. Y. Sulaiman ◽  
K. Sopian ◽  
C. H. Lim ◽  
E. Salleh ◽  
...  
Keyword(s):  
Air Conditioning ◽  
Cooling Water ◽  
Cooling Capacity ◽  
Hot Water ◽  
Activated Carbon Fiber ◽  
Coefficient Of Performance ◽  
Weather Data ◽  
Adsorption System ◽  
Water Storage Tank ◽  
Chilled Water

The modeling of the performance of a one refrigeration ton (RT) solar assisted adsorption air-conditioning refrigeration system using activated carbon fiber/ethanol as the adsorbent/adsorbate pair has been undertaken in this study. The effects of hot water, cooling water, chilled water inlet temperatures, and hot water and chilled water flow rates were taken into consideration in the optimization of the system and in the design of the condenser, evaporator, and hot water storage tank. The study includes analysis of the weather data and its effect on both the adsorption system and the cooling load. This is then followed by estimation of the cooling capacity and coefficient of performance (COP) of the adsorption system as a function of the input parameters. The results of the model will be compared to experimental data in a next step.

Simulation and performance study of a two-bed adsorption cooling system operated with activated carbon-ethanol

2021 ◽  
pp. 095440622110420
Author(s):  
V Baiju ◽  
A Asif Sha ◽  
NK Mohammed Sajid ◽  
K Muhammedali Shafeeque
Keyword(s):  
Water Temperature ◽  
Performance Optimization ◽  
Cooling System ◽  
Cooling Water ◽  
Hot Water ◽  
Coefficient Of Performance ◽  
Cooling Power ◽  
Performance Study ◽  
Evaporator Temperature ◽  
Adsorption Cooling System

This paper presents the transient model of a two-bed adsorption cooling system performed in the SIMULINK platform. The inlet chilled water temperature in the evaporator, temperature of cooling water and hot water temperature of the adsorbent bed and its effect on systems coefficient of performance, refrigeration effect and specific cooling power have been studied and presented. It is observed that the systems coefficient of performance is 0.57 when the inlet hot water temperature about 80 °C. In this study, the optimum cooling power and systems coefficient of performance are also determined in terms of the phase time, shifting duration and hot water inflow temperature. The results indicates that the cooling water and hot water inlet temperatures significantly affects the coefficient of performance, specific cooling power and cooling power of the system. The effect of mass flow rate on the cooler efficiency is also presented. A two bed adsorption system of capacity 13.5 kW having an evaporator and condenser temperatures of 6°C and 28°C, respectively, are considered for the present investigation. The adsorbent mass considered is 45 kg with a shifting duration of 20 sec. The result of this study gives the basis for performance optimization of a practical continuous operating vapour adsorption cooler.

scholarly journals Performance Investigation of a Two-Bed Type Adsorption Chiller with Various Adsorbents

Energies ◽  
2020 ◽  
Vol 13 (10) ◽  
pp. 2553 ◽  
Author(s):  
Jung-Gil Lee ◽  
Kyung Jin Bae ◽  
Oh Kyung Kwon
Keyword(s):  
Performance Evaluation ◽  
Physical Properties ◽  
Water Temperature ◽  
Silica Gel ◽  
System Performance ◽  
Waste Heat ◽  
Sustainable Energy ◽  
Cooling Capacity ◽  
Hot Water ◽  
Adsorption Chiller

In this study, the performance evaluation of an adsorption chiller (AD) system with three different adsorbents—silica-gel, aluminum fumarate, and FAM-Z01—was conducted to investigate the effects of adsorption isotherms and physical properties on the system’s performance. In addition, the performance evaluation of the AD system for a low inlet hot-water temperature of 60 °C was performed to estimate the performance of the system when operated by low quality waste heat or sustainable energy sources. For the simulation work, a two-bed type AD system is considered, and silica-gel, metal organic frameworks (MOFs), and ferro-aluminophosphate (FAPO, FAM-Z01) were employed as adsorbents. The simulation results were well matched with the laboratory-scale experimental results and the maximum coefficient of performance (COP) difference was 7%. The cooling capacity and COP of the AD system were investigated at different operating conditions to discuss the influences of the adsorbents on the system performance. Through this study, the excellence of the adsorbent, which has an S-shaped isotherm graph, was presented. In addition, the influences of the physical properties of the adsorbent were also discussed with reference to the system performance. Among the three different adsorbents employed in the AD system, the FAM-Z01 shows the best performance at inlet hot water temperature of 60 °C, which can be obtained from waste heat or sustainable energy, where the cooling capacity and COP were 5.13 kW and 0.47, respectively.

scholarly journals Real Air-Conditioning Performance of Ejector Refrigerator Based Air-Conditioner Powered by Low Temperature Heat Source

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 711
Author(s):  
Tongchana Thongtip ◽  
Natthawut Ruangtrakoon
Keyword(s):  
Heat Source ◽  
Thermal Comfort ◽  
Water Temperature ◽  
Test Performance ◽  
Air Conditioning ◽  
Cooling Water ◽  
Hot Water ◽  
Cooling Load ◽  
Air Conditioner ◽  
Comfort Condition

In this present work, the air-conditioning test performance of an ejector refrigerator-based air-conditioner (ERAC) was proposed. The ERAC was operated as the water chiller to produce the cooling load up to 4.5 kW. The chilled water temperature was later supplied to the fan-coil unit for producing the thermal comfort condition. The cooling water used to cool the condenser was achieved from the cooling tower which was operated under the hot and humid ambient. This is to demonstrate the feasibility of using the ERAC in real working conditions. The cooling load supplied to the air-conditioned space was applied by the air heater. The ERAC could efficiently be operated to produce the thermal comfort condition which was driven by the hot water temperature (Thot) of 90–98 °C. The system performance could vary with the heat source temperatures, cooling load, primary nozzle, and air-conditioned space temperature. The optimal performance was determined when varying the Thot, and, hence, the optimal Thot was indicated. The optimal Thot varied significantly with variations in the working condition. The test results demonstrated high potential to further using the ejector refrigeration system in the actual air conditioning application.

scholarly journals Performance Testing and Analysis of Silica Gel-Water Adsorption Refrigerator

2022 ◽  
Vol 2160 (1) ◽  
pp. 012032
Author(s):  
Hongxuan Li ◽  
Tonghua Zou ◽  
Qingling Hui ◽  
Ting Li ◽  
Walter Mittelbach
Keyword(s):  
Low Temperature ◽  
Heat Source ◽  
Water Temperature ◽  
Silica Gel ◽  
Water Adsorption ◽  
Cooling Capacity ◽  
Hot Water ◽  
Low Grade ◽  
Adsorption Refrigeration ◽  
Refrigeration Capacity

Abstract In recent years, adsorption refrigeration technology has attracted wide attention from experts and scholars at home and abroad due to its environmental friendliness and energy saving advantages. In order to study the effectiveness of adsorption refrigeration technology to recover low-grade energy, a silica gel-water adsorption refrigeration system was proposed, which can effectively utilize low-grade energy such as industrial waste heat. The structure and composition of the system are introduced. The operation performance of the unit is tested under different working conditions by orthogonal experimental method, and the experimental results are analyzed. The effects of hot water temperature and flow, chilled water temperature and flow on the refrigeration capacity and COP value of the system are obtained. The experimental results show that under the low-temperature heat source of 55-75°C, the cooling capacity of the system can reach 5.3-12 and the COP value can reach 0.36-0.56. Under the same hot water temperature difference, the cooling capacity and COP value of the system increase rapidly under the condition of changing the hot water temperature at low temperature, indicating that increasing the heat source temperature at low temperature has a greater impact on the system performance. Through the analysis of primary and secondary effects, it is concluded that the inlet temperature of hot water is the main factor affecting the refrigeration capacity and COP value of the system.

scholarly journals Kajian Sifat Fisika-Kimia Air Bahang dan Indeks Pencemaran di Perairan PLTU Sumbawa Barat

Kappa Journal ◽  
2021 ◽  
Vol 5 (1) ◽  
pp. 57-67
Author(s):  
Amirul Hilmi ◽  
◽  
Andi Maria Ulfa ◽  
Muh. Iman Darmawan ◽  
◽  
...  
Keyword(s):  
Water Temperature ◽  
Sea Water ◽  
Cooling Water ◽  
Chemical Properties ◽  
Pollution Index ◽  
Quality Standard ◽  
Hot Water ◽  
Sample Point ◽  
The Status ◽  
Control And Prevention

This research examines the physical and chemical properties of the potential contamination of condenser cooling water (heat water) at the 2x7 MW West Sumbawa Steam Power Plant. Method’s this research is direct observation in the field. The determination of the sample point was done by purposive sampling. The results showed that the hot water had met the predetermined quality standards, namely a pH of 8.21, a temperature of 38.50C and a content of free chlorine (Cl2) of 0.03 mg / L. There was an increase in sea water temperature in a radius of 17 meters east and west by 80C from 280C to 360C. Direct discharge of hot water has the potential to pollute the marine prawn environment around the 2x7 MW West Sumbawa PLTU. From the results of the study, it was found that the temperature of the hot water had met the specified quality standard, which was 40oC, but direct disposal caused the sea water temperature to rise, exceeding the set sea water temperature quality standard of 320C and the temperature increase should not be more than 20C from the temperature. at first. The status of sea water quality due to the entry of hot water is determined using a pollution index. From the calculation results obtained PIj of 1.125 at the sample point Outfall 2, meaning that the sea water conditions at a radius of 17 meters are lightly polluted. As a form of control and prevention of pollution due to the entry of high temperature hot water, continuous monitoring is necessary and it is necessary to create a mixing pool between sea water and hot water before the heat is discharged into the sea.

Study of the Cooling Performance of a Mist-Type Regenerative Evaporative Cooler Under Different Feed Water Temperature

2020 ◽  
Vol 28 (02) ◽  
pp. 2050011
Author(s):  
B. S. Arun ◽  
V. Mariappan
Keyword(s):  
Water Temperature ◽  
Water Solution ◽  
Water Film ◽  
Cooling Capacity ◽  
Hot Water ◽  
Feed Water ◽  
Liquid Desiccant ◽  
Cooling Performance ◽  
Evaporative Cooler ◽  
Feed Water Temperature

In hot and humid climates, evaporative cooler is coupled with desiccant dehumidifier to obtain effective cooling. To realize the M-cycle-based cooler which combines liquid desiccant regeneration and evaporative cooling in a single apparatus, the effect of different feed water temperature on cooling performance is investigated in this paper. It was observed that wetting water film layer of conventional regenerative evaporative cooler (REC) carries a significant amount of sensible heat from the hot water/solution which reduced the wet-bulb effectiveness of the cooler. To enhance its effectiveness, an ultrasonic atomization mist REC was proposed. The influence of different intake conditions on cooling performance was studied and found that mist REC performed better than conventional cooler for higher feed water temperature. The wet-bulb effectiveness of the cooler ranged from 0.56 to 1.15 with maximum cooling capacity of 580[Formula: see text]W, which is comparable to the previous studies. This prototype can be further developed to an ultrasonic liquid desiccant waterless evaporative cooler.

scholarly journals Feasibility Analysis of a Membrane Desorber Powered by Thermal Solar Energy for Absorption Cooling Systems

2020 ◽  
Vol 10 (3) ◽  
pp. 1110 ◽  
Author(s):  
Jonathan Ibarra-Bahena ◽  
Eduardo Venegas-Reyes ◽  
Yuridiana R. Galindo-Luna ◽  
Wilfrido Rivera ◽  
Rosenberg J. Romero ◽  
...  
Keyword(s):  
Experimental Data ◽  
Water Vapor ◽  
Solar System ◽  
Waste Heat ◽  
Cooling Water ◽  
Solution Temperature ◽  
Hydrophobic Membrane ◽  
Cooling Systems ◽  
Libr Solution ◽  
Absorption Cooling

In absorption cooling systems, the desorber is a component that separates the refrigerant fluid from the liquid working mixture, most commonly completed by boiling separation; however, the operation temperature of boiling desorbers is generally higher than the low-enthalpy energy, such as solar, geothermal, or waste heat. In this study, we used a hydrophobic membrane desorber to separate water vapor from an aqueous LiBr solution. Influencing factors, such as the H2O/LiBr solution and cooling water temperatures, were tested and analyzed. With the experimental data, a solar collector system was simulated on a larger scale, considering a 1 m2 membrane. The membrane desorber evaluation shows that the desorption rate of water vapor increased as the LiBr solution temperature increased and the cooling water temperature decreased. Based on the experimental data from the membrane desorber/condenser, a theoretical heat load was calculated to size a solar system. Meteorological data from Emiliano Zapata in Mexico were considered. According to the numerical result, nine solar collectors with a total area of 37.4 m2 provide a solar fraction of 0.797. The membrane desorber/condenser coupled to the solar system can provide an average of 16.8 kg/day of refrigerant fluid that can be used to produce a cooling effect in an absorption refrigerant system.

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