The main components of a solar assisted desiccant cooling system are shown in the figure on the right. Since mass transfer occurs between the system and its envi ronment, they are commonly referred to as opencycle systems. The chp system did not always deliver high enough water. Through performance studies of desiccant cooling system, it has proven its feasibility and advantages of energy and cost saving in different climatic conditions. The coefficientofperformance of this novel heat recoverydesiccant cooling system is proved to be as high as. The system is operable in either an open or closed system to generate either cold gas or cold fluid or both. Gommed and grossman 10 developed the prototype of the liquid desiccant cooling system assisted by the flat scs using liclh 2 o as its working fluid. Experts in the field discuss topics from enthalpy, lumped models for heat and mass transfer, and desiccant. The basic process in providing conditioned air may be described as follows. The experimental works and some parametric investigations. Desiccant evaporative cooling dec is one of those techniques.
Ascendant easily allows a design consultant compliance with all ashraeaia guideline conditions while using. These systems all use a liquid or solid material called a desiccant to remove water vapor from the air. The addiction of a desiccant dehumidifier to an evaporative cooling air conditioning system provides a humidity control separate of the temperature control. The rankine engine vapor compression and the absorption cooling units operate on the basis of closed cyclesfixed amounts of working fluid are circulated within sealed equipment. For this study, the desiccant system was evaluated. Principles of desiccant cooling desiccant cooling consists in dehumidifying the incoming air stream by forcing it through a desiccant material and then drying the air to the desired indoor temperature. Application specifications including air flow capacities, heat sources, space limitations and power requirements determine which liquid desiccant system will. Analysis of a solid desiccant cooling system with indirect evaporative cooling bellemo, lorenzo publication date. An evaporative and desiccant cooling system for air. The thermally driven cooling cycle is a combination of evaporative cooling with air dehumidification by a desiccant, i. Desiccantassisted cooling fundamentals and applications.
There are common features to the systems, along with features unique to each system. Liquid desiccant systems overview alfa laval kathabar offers a full line of liquid desiccant system series including, fv, fh, fp and sp. A heat supply is needed in the system to regenerate the desiccant natural zeolite and a lowgrade heat at a temperature of about 60. This paper describes recent published design advances that have been made in desiccant cooling systems. The purpose of the present study is to investigate experimentally a liquid desiccant dehumidifier with cooling capacity using compressible heat pump system, and develop a correlation of moisture. Air conditioning, humidity, sodium chloride, hvac, engineering thermodynamics report this link. Conditioners are available in airflows ranging from 1,500 cfm to 7,500 cfm. An evaporative and desiccant cooling system for air conditioning in humid climates evaporative cooling operates using water and air as working fluids. This case is under the preset conditions that the environment air. In desiccant cooling cycles, the desiccant reduces the humidity of the air by removing moisture from the air. Analysis of advanced solar hybrid desiccant cooling systems for. Introduction to solar cooling systems ced engineering.
The thermal and reversible cops of an open desiccant cooling system depend on operating conditions of the system. Desiccant dehumidification wheel upstream of cooling coil, parallel regeneration dedicated outdoorair application providing insights for todays hvac system designer trane engineers newsletter volume 344 3. Such a solid desiccant cooling system with a backup vapour compression system is simulated and the performance of the system is evaluated to study its feasibility in four cities in the united states. Therefore it could be used potentially as a liquid desiccant in solar refrigeration systems providing low grade cooling in particular systems for cooling greenhouses in hot and humid climates. Fundamentals and applications presents different approaches to the mathematical modeling and simulation of desiccant wheels, as well as applications in thermal comfort and humidity controlled environments. These systems are designed to remove moisture from the air to control humidity in commercial buildings and industrial processes. Munters systems are used by more than 20 major industries in hundreds of applications. Department of defense dod uses desiccant cooling technology to.
Desiccant cooling sys tems international journal of lowcarbon t echnologies 2016, 0, 1 17 11 of 17. Liquid desiccant dehumidification system components. Liquid desiccant dehumidification systems product guide sea level imperial units kds liquid desiccant systems product guide liquid desiccant systems liquid desiccant systems are the most efficient dehumidification system, when cool and dry air is needed and are the perfect solution for a wide range of applications for industrial, commercial, institutional, and greenleed facilities. Performance analysis of a twostage desiccant cooling system. Modelling and analysis of a desiccant cooling system.
However, when the desiccant cooling system must handle the entire load, it overdries the process air so evaporative cooling can be used for the sensible cooling. Desiccant cooling system is one of the options in our daily life to provide the best indoor air quality and thermal comfort with the minimum consumption of energy. Solar assisted desiccant air conditioning system for hot. Liquid dessicant solar airconditioner system overview. Explore hybrid solar desiccant cooling system with free download of seminar report and ppt in pdf and doc format. Experimental setup of solar desiccant cooling system table 1 shows specification components of solar hybrid desiccant cooling system. However, there are some technical challenges of developing an efficient heat pump that runs. Series regeneration the latest advance in desiccant based dehumidification places the desiccant wheel in series with the cooling coil figure 7, with the regeneration side. Hybrid desiccant cooling system free download as powerpoint presentation. An overview of opencycle desiccant cooling systems and.
Analysis of a solid desiccant cooling system with indirect evaporative cooling. Liquid desiccant system the unit shall be a complete, factory assembled and tested, system. The operation of a desiccant cooling system is based on the use of a rotary dehumidifier desiccant wheel in which air is dehumidified. Figure 5 shows another liquid desiccant cooling system in which strong and weak desiccant flows in the whole system. Advantages of desiccant enhanced cooling it extends the climatic applicability scope of the evaporative cooling to the hot and humid zones. Liquid desiccant cooling system newest air conditioning. The diameter of the wheel is 250 mm and its width is 533 mm. Table 2 shows the pros and cons of using a desiccant cooling system. Zhang 3 introduced a twostage desiccant cooling system with evaporative cooling and a heat recovery wheel. The primary research on liquid desiccant dehumidifier with. District heating plants burning urban waste are particularly favourable, since urban waste has to be burnt year round, the heat being mostly dissipated through cooling towers in the summer season.
To find effect of dehumidification capacity on the performance of cooling system, four configurations of desiccant cooling system have been investigated. Also explore the seminar topics paper on hybrid solar desiccant cooling system with abstract or synopsis, documentation on advantages and disadvantages, base paper presentation slides for ieee final year mechanical engineering me or production automobile students for the year 2019. Desiccant cooling systems are basically open cycle systems, using water as refrigerant in direct contact with air. Description download liquid desiccant cooling system newest comments. Pdf desiccant cooling systems have been considered as an efficient method of controlling moisture content in supply air. A solar powered liquiddesiccant cooling system for. In this system, liquid desiccant cooling system along with an indirect evaporative cooler was used to subcool the refrigerant of the liquid desiccant cooling cycle.
Apr 25, 2012 nrel combined desiccant materials, which remove moisture from the air using heat, and advanced evaporative technologies to develop a cooling unit that uses 90% less electricity and up to 80% less. Desiccant cooling system a novel technique for air. The desiccant wheel is designed to operate with both a 50% area for reactivation and 50% for process 5050. A typical system combines a dehumidifier that uses dry desiccant wheel, with direct or indirect evaporative systems and a sensible cooling system. Now days, air conditioning systems are a must for almost every commercial and residential building to achieve comfortable indoor conditions. Liquid desiccant based airconditioning systems ldacs 221 heating when available. This work assesses the energy savings possible from developing hybrid desiccantvapor compression air conditioning systems and makes recommendations for. Advantages of desiccant enhanced cooling it extends the climatic applicability scope of the evaporative cooling. Sharpes model 6760 desiccant sy stem includes 100% indicating silica. The purpose of the research reported in this paper is the procurement of continuous operating data on a solar desiccant cooling system assembled from commercially available com. The performance of the whole desiccant cooling system is dependent on the performance of its components. It consists in water evaporation, through the passage of an air flow, thus decreasing the air temperature. Industrial desiccant dehumidification system munters.
Munters desiccant dehumidification systems remove moisture from the air by using a desiccant. The increasing energy demand, and increasing oil prices and pollution levels raise the need for alternative. A study of desiccantbased cooling and dehumidifying system in. Davies 2005 theoretically demonstrated a solar powered liquid desiccant cooling system that lowers summer maximum summer temperatures by 5oc. Desiccant cooling systems are heatdriven cooling units and they can be used as an alternative to the conventional vapor compression and absorption cooling. Analysis of a solid desiccant cooling system with indirect. Solar thermal energy is hereby used to provide cooling. A typical recirculation cycle for the desiccant cooling system is shown in figure 21 b. An overview of opencycle desiccant cooling systems and materials. Liquid desiccant cooling system newest free download as powerpoint presentation. Us5460004a desiccant cooling system with evaporative.
A desiccant system can also supplement a conventional airconditioning system. Small packaged units combine both the conditioner and regenerator into a single component for easy installation. Liquid desiccant system an overview sciencedirect topics. Liquid desiccant air conditioning by advantix systems.
The system which will be studied in this report is a desiccant cooling system based on the model designed by the company munters ab. A rotary wheel system can be adopted to ensure a continuous operation. Desiccant cooling systems are heatdriven cooling units and they can be used as an alternative to the conventional vapor compression and absorption cooling systems. Desiccant cooling systems process water vapor in the earths atmosphere.
Desiccant cooling system an overview sciencedirect topics. Desiccant cooling system a novel technique for air conditioning. Desiccant cooling analysis simulation software, energy. Hybrid desiccant cooling system air conditioning hvac. Solar assisted desiccant cooling system is an attractive and cost effective application for air conditioning system.
New technologies using desiccant dehumidification applied to evaporative cooling systems for human thermal comfort have been developed, such as presented. Typically, a desiccant dehumidification system is utilized for applications below 45% rh down to 1% rh. An evaporative and desiccant cooling system for an. Munters manufactures and services desiccant dehumidification systems. Modelling of a solar desiccant cooling system using a. Modelling and analysis of a desiccant cooling system using. Desiccant cooling systems, on the other hand, may be designed for open. The cooling effect of a dec system is based on the adiabatic cooling principle. A novel design of a hybrid system of vcs and lds was proposed by she and colleagues.
Desiccant cooling dec systems are an alternative solution to coolingbased. Liquid desiccant system the unit shall be a complete, factory assembled and tested, system suitable for outdoor installation. Lowtemperature solar heat can drive a desiccant cooling system. Moreover, the desiccant solution was regenerated using the condensing heat of the vcs. A soliddesiccant cooling system for greenhouses amel rjibi, sami kooli, amen allah guizani research and technology center of energy, thermal processes laboratory, hammam lif, b. For this purpose, liquid or solid materials can be employed.
Warm and humid air enters the slowly rotating desiccant wheel and is dehumidified by adsorption of water 12. Ascendant is a conventional cooling active desiccant dehumidification system, performance optimized to deliver and control low dew point air while minimizing regeneration energy input in compliance with ashrae aia guidelines. In a liquid desiccant cooling system, the working fluid flows between the absorber and the regenerator. A system for cooling and gases in which the process gas is dehumidified in a desiccant module and subsequently treated in a heat exchanger. Refrigeration section optional for pre andor post cooling b. Analysis of advanced solar hybrid desiccant cooling. A desiccant cooling system combined to an evaporative cooler 43. A solid desiccant cooling system for greenhouses amel rjibi, sami kooli, amen allah guizani research and technology center of energy, thermal processes laboratory, hammam lif, b. Through the parametric study, they demonstrated that conditions of the ambient air are the major parameters considerably affecting the dehumidification process in the liquid desiccant system. Moreover, a desiccant system can be used in combination with evaporative cooling system to maintain the temperature and moisture of incoming. Dryaire desiccant system 310595f model 6760 maximum operating pressure.
Desiccant based systems are more economical than refrigeration systems at lower temperatures and lower moisture levels. Additional heat exchanger and gas washers may be included in the system. It is a flexible system that is able to provide cooling in summer and heat during. Dec of a desiccant cooling system depends strongly on the conditions of ambient air and supply air. In this paper, basically the principles of desiccant cooling systems have been discussed and studied. Desiccant cooling system operation the dehumidifier is the heart of a desiccant cooling. Alfa laval kathabar offers a full line of liquid desiccant system series including, fv, fh, fp and sp. In this paper, we propose a desiccant cooling system with certain operating.
Moisture in the air is adsorbed by a sorption wheel which is regenerated with solar thermal heat. Hybrid desiccant cooling system is used desiccant wheel for dehumidification and then further cool in indirect evaporative cooler, the solar energy is used for desiccant regeneration. Warm and humid air enters the slowly rotating desiccant. The main components of the desiccant based system consist of desiccant dehumidifier, heat recovery wheel, desiccant heater and evaporative cooler. Liu, shuli 2008 a novel heat recoverydesiccant cooling. This document provides an overview of desiccant cooling technology and provides readers with reference materials for more indepth analyses. Case study analyzed ac consists of an ahu equipped with a hybrid desiccant cooling that integrates desiccant, evaporative and conventional cooling technologies. Solar assisted desiccant air conditioning system for hot and. Hybrid solar desiccant cooling system seminar report, ppt. The desiccant dewpoint cooling ddc system 10 is a specific dec system, constituted by a desiccant wheel dw made of silica gel, a heat recovery unit hru, a dew point cooler dpc, and a heat source connected to the system by means of a secondary hot water circuit. It is especially good in applications where the latent thermal load is high comparing to the sensitive load, or when they get the maximum in different time.
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