The desalination yield in humidification-dehumidification (HDH) process is increased by proposing cooling plant integration with two stage operation. The current work is targeted on the investigation of vapor absorption refrigeration (VAR) parameters on overall energy utilization factor (EUF). The dephlegmator heat is recovered internally in VAR instead of rejecting to environment. This work can be used to control the operational conditions of VAR to enhance the desalination and cooling together. The studied process parameters in VAR are strong solution concentration, separator or generator temperature, dephlegmator effectiveness, circulating water inlet temperature and evaporator temperature. Out of these five variables, lower limit of separator temperature, upper limit of dephlegmator effectiveness and lower limit of circulating water temperature are fixed in the specified range to attain the optimum strong solution concentration and optimum evaporator temperature. At the specified boundaries of three variables, the optimized strong solution concentration and evaporator temperature are 0.47 and 10 °C respectively. At this condition, the maximized cycle EUF is 0.358. © 2016 Faculty of Engineering, Alexandria University

Chiranjeevi C

Department of Thermal and Energy Engineering

School of Mechanical Engineering

Vellore Campus

Srinivas T.

Fulltext

Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Alexandria Engineering Journal

Humidification–dehumidification (HDH) desalination works based on a water cycle principle and involves air humidification and condensation (dehumidification). The cooling of humid air with chilled water increases the desalination and results in cold air suitable for air conditioning process. The merits of the proposed HDH desalination and cooling are not analyzed and compared in the literature. Therefore, the performance results of HDH with normal water (current technology) and HDH with chilled water (proposed idea) are compared to highlight the merit of this cycle. The combined cycle for desalination and cooling has been solved thermodynamically with psychrometric properties. The results are validated with a laboratory experimental setup. The examined operational process conditions are hot water inlet temperature, efficiency of humidifier, and vapor absorption refrigerator's (VAR's) evaporator exit temperature. The focused results are desalination, cooling and energy utilization factor (EUF). The comparative study recommends the use of chilled water in the final stage. The two stage desalination with dehumidification by normal water in the first stage and chilled water in combined two stages improves the cycle EUF from 0.18 to 0.33. Out of 300 W of cooling generation, 100 W is used for dehumidification and the remaining 200 W is available for air conditioning process at 15 N⋅m3 h−1 of air. © 2017 Elsevier Ltd and IIR

International Journal of Refrigeration

Augmented desalination with cooling integration

Humidification-dehumidification (HDH) desalination is a simple and cost effective solution to convert the saline water into desalinated water. In current work, desalination yield has been augmented with two stage HDH integrated cooling plant. A pilot plant has been developed and analyzed with experimental and simulation studies. The identified operational variants are hot saline water supply to humidifiers and its inlet temperature. The saline water is heated in a solar water heater (SWH) and supplied to two humidifiers and two air preheaters. The simulated results developed for subsystems are validated with the experimental readings. Desalination yield is not satisfactory level at lower water temperature in the first stage plant but there is no such limitation in the second stage operation. Nearly 1.5 LPH of desalinated water is resulted at 15m3/h of air. The energy utilization factor (EUF) of two stage plant is concentrated at higher side compared to the single stage plant's EUF. The increased flow of saline water in humidifiers and its high temperature is favoring the desalination output but with a penalty in cooling effect. © 2015 Elsevier B.V.

Desalination

Experimental and simulation studies on two stage humidification–dehumidification desalination and cooling plant

Some commercial units and industries need more amount of cooling than the power such as cold storage, shopping complex, etc. In this work, a new cooling cogeneration cycle (Srinivas cycle) has been proposed and solved to generate more cooling with adequate power generation from single source of heat at hot climatic conditions with ammonia–water mixture as a working fluid. The operational processes conditions for the proposed cooling cogeneration plant are different compared to the power-only (Kalina cycle system) system and cooling-only (vapor absorption refrigeration) system. This work focused to generate the optimum working conditions by parametric analysis from thermodynamic point of view. An increase in cycle maximum temperature is only supporting the power generation but not the cooling output. Cooling output is also 15 times more than power generation. So, it has been recommended to operate the integrated plant with low temperature heat recovery. The resulted cycle thermal efficiency, plant thermal efficiency, specific power, specific cooling, cycle power efficiency, cycle coefficient of performance (COP), and solar collector's specific area are 27%, 10%, 15 kW, 220 kW, 1.8%, 0.25, and 10 m2/kW, respectively.

Journal of Solar Energy Engineering

Investigation on Operating Processes for a New Solar Cooling Cogeneration Plant

Two or more than two outputs from a single source result an overall high energy utilization factor (EUF) compared to the single output system. In this work, two stage humidification and dehumidification (HDH) desalination system has been extended with cooling system integration. Solar flat plate collector and concentrating collector are selected respectively for HDH desalination and single effect vapor absorption refrigeration (VAR) plant. The cooling after desalination increases the yield of distillation compared to without its integration. The sequence of operations in the combined plant is first stage air preheatinghumidification-dehumidification, second stage air preheating-humidification-dehumidification and final cooling of air with chilled water. The work is aimed on thermodynamic study for maximization of EUF for cycle and plant. The role of humidifier efficiency, its effectiveness, hot water temperature and chilled water temperature (by varying VAR evaporator temperature) has been studied on integrated performance. The resulted distilled water is 670 LPH with 75kW cooling at unit volume of air (1m3/s). The cycle EUF and plant EUF are 0.58 and 0.33 respectively. © 2014 Elsevier B.V.

Journal	Data powered by TypesetAlexandria Engineering Journal
Publisher	Data powered by TypesetElsevier BV
ISSN	1110-0168
Open Access	No