Specific Daily Water Production Research Articles

Solar-powered hybrid adsorption desalination/humidification-dehumidification system

Eco-friendly materials used in adsorption desalination system represent a good alternative to avoid the problems of pollution and global warming. Adsorption desalination technology has low relative performance and still needs more development. This work investigates novel configurations of solar-powered adsorption desalination system using composite sodium polyacrylate (SP) as adsorbent material integrated with humidification-dehumidification desalination system driven by solar energy or waste heat. Cost analysis of those novel configurations and weather effects were studied beside the performance. MATLAB and TRNSYS used hot regions' weather data to carry out the model. Sodium polyacrylate in the forms of raw sodium polyacrylate and SP/CaCl2 is used as adsorbent material. Findings reveal that for conventional solar adsorption desalination system using raw sodium polyacrylate or SP/CaCl2, the highest specific cooling power is introduced by the composite adsorbent. When utilizing raw sodium polyacrylate in the hybrid system with heat recovery, it gives relatively high values of specific daily water production, reaching 55.8 m3/ton in June, and it decreased to 41.7 m3/ton in December. Gained output ratio has been studied, and it changes from 1.73 in January to 1.58 in June and 1.75 in December. When utilizing SP/CaCl2, The hybrid system with heat recovery reached a SDWP value of 77.3 m3/ton in June, and it decreased to 51.8 m3/ton in December. Results also reveal that the SP/CaCl2 system powered by waste heat provides the cheapest desalinated water among all systems at 0.49 $/m3.

Towards enhanced heat and mass exchange in adsorption systems: The role of AutoML and fluidized bed innovations

The selection of optimal design and the most efficient operational parameters for energy devices constitute a priority task for sustainable development and increasing energy efficiency within the net-zero emissions strategy. This is particularly important in adsorption cooling and desalination systems with poor performance due to unfavourable heat transfer conditions in conventional packed beds of adsorption chillers (ACs). Therefore, looking for additional ways of performance improvement is still challenging, especially covering different design variants and operational strategies. The existing complex, time-consuming and costly analytical, numerical and experimental methods, usually focused on a specific design and operating parameters of conventional packed adsorption beds, cannot tackle these comprehensive problems. Since artificial intelligence (AI) based models are considered tools that sometimes may overcome the shortcomings of the programmed computing approach and the experimental procedures, the paper introduces automated machine learning (AutoML) as a general approach for the design and optimization study of adsorption cooling and desalination systems. The double-effect, i.e. specific cooling capacity (SCP) and specific daily water production (SDWP) of various adsorption chillers (ACs) operating in large-, pilot- and small-scale adsorption cooling and desalination systems, is considered in the study. The paper also presents a novel big data optimization procedure for selecting the best operating and design strategy in adsorption cooling and desalination technology. Finally, a new concept of fluidized bed-type application in adsorption chillers is proposed, which allows for enhancing the performance of ACs.The presented approach can be referred to as a complementary design technique in adsorption cooling and desalination systems, besides the existing complex analytical and time-consuming numerical methods and expensive experiments.

Adsorbent beds packed in triply periodic minimal surface-derived structures and their performance in adsorption desalination/cooling systems

The present study aims at improving the performance of adsorption desalination/cooling systems (ADCs) by packing the adsorbent materials inside triply periodic minimal surface (TPMS) structures. In that respect, solid and sheet types of metallic networks-based TPMS (e.g., Gyroid and Diamond) were addressed to improve the performance of ADCs. Using CFD simulations, the TPMS structures were compared to the finned tube-packed adsorbers based on specific daily water production (SDWP) and specific cooling power (SCP). The computational model was developed and hence verified using the most relevant literature. The influence of heat transfer area, effective thermal conductivity, effective diffusivity, and tortuosity on SDWP and SCP was investigated for the TPMS-derived and finned tube structures. Those structures were also examined using variant porosity levels. The results indicated that increasing TPMS porosity resulted in lower SDWP and SCP; however, TPMS still attained an improvement in SDWP and SCP compared to finned tube adsorbers. At a porosity of 0.8, SDWP of 10.4 m3/ton was attained by the sheet network of Diamond, which was 19.4% superior to that of the finned tube structure. At a porosity of 0.2, the sheet network of Diamond attained SDWP and SCP of 20.1 m3/ton and 627.4 W/kg, respectively.

Thermodynamic Analysis and Performance Assessment of a Novel Solar-Based Multigeneration System for Electricity, Cooling, Heating, and Freshwater Production

Abstract This study offers a comprehensive assessment of the thermodynamic performance of a novel solar-based multigeneration system, which caters to the energy needs of a sustainable community by producing electricity, cooling, heating, and freshwater. The solar-based multigeneration system is comprised of four main components: the thermal subsystem of the parabolic trough collector (PTC) employing CO2 as a heat transfer fluid, a single-effect absorption refrigeration cycle (ARC), a supercritical CO2 (S-CO2) cycle, and an adsorption desalination (AD) cycle with heat recovery employing aluminum fumarate metal–organic framework (MOF) adsorbent material. A comprehensive parametric study was performed on the proposed solar-based multigeneration system by varying key parameters to evaluate its performance. It is found that the thermal and exergy efficiencies of a PTC were evaluated to be 68.35% and 29.88%, respectively, at a fixed inlet temperature of 225 °C and solar irradiation of 850 W/m2 and also a slight reduction in the ARC cycle when examining the variation in the thermal and exergetic COPs for the generator temperature. Additionally, the thermal and exergy efficiencies of electricity, cooling, and heating were determined to be 20.41% and 21.93%, 41.34% and 3.51%, and 7.14% and 3.07%, respectively, at the operating condition. The maximum specific daily water production (SDWP) value of 12.91 m3/ton/day and a gain output ratio (GOR) of 0.64 were obtained under steady operating conditions in the AD cycle.

Development and assessment of a novel integrated system powered by parabolic trough collectors for combined power, heating and freshwater production

Abstract Hybrid solar-based integrated systems represent a viable solution for countries with abundant solar radiation, as they provide energy needs in an environmentally friendly way, offering a sustainable and economically advantageous energy solution that utilizes a free source of energy. Therefore, this research offers a thermodynamic evaluation of a novel integrated system driven by solar energy that aims to produce power, heating and freshwater. The integrated system consists of a parabolic trough collector that uses CO2 as its working fluid and implements the supercritical carbon dioxide cycle to generate power and heating. The integrated system also includes an adsorption desalination system with heat recovery between the condenser and evaporator, which employs a cutting-edge material called an aluminium fumarate metal–organic framework to produce fresh water. For the modelling of a novel system, an engineering equation solver, which is considered a reliable tool for thermodynamic investigations, is employed. The effectiveness of an integrated system is evaluated using a mathematical model and different varying parameters are examined to ascertain their influence on thermal and exergy efficiency, specific daily water production and gained output ratio. The results revealed that the parabolic trough collector achieved a thermal efficiency of 67.2% and an exergy efficiency of 41.2% under certain conditions. Additionally, the thermal efficiencies for electrical and heating were obtained 24.68% and 9.85%, respectively. Finally, the specific daily water production was calculated, showing promising results and an increase from 7.1 to 12.5 m3/ton/day, while the gain output ratio increased from 0.395 to 0.62 when the temperature of hot water increased from 65°C to 85°C, under the selected conditions.

Cost analysis and performance investigation of solar-powered desalination system utilizing modified sodium polyacrylate adsorbent material

Seawater has been desalinated using various processes at different techniques, most of which depend on fossil fuels. On the contrary, there is a need for environmentally benign desalination systems. Adsorption desalination system (ADS) is one of these systems thatemploy eco-friendly materials to reduce environmental pollution and global warming. This paper examines the performance metrics of promising materials used in ADS to lower desalinated water prices. This research uses sodium polyacrylate (SP), special SP/(NH4)2CO3 activated materials, and SP/CaCl2 composite to theoretically examine ADS's performance and cost analysis. Also, ADS performance with and without heat recovery (HR) is compared. Using tools from MATLAB and TRNSYS, the model is carried out over a year using live weather data from hot regions. Results show that the SP/CaCl2 composite has a relatively high specific daily water production (SDWP) of 15 m3/ton with COP = 0.67. The SDWP can be increased up to 45 m3/ton if heat recovery is used in the system. The cost of desalinated water is estimated at 3.8 $/m3 using Solar energy and 0.63 $/m3 using waste heat evaluated for a system with HR.

Comparative analysis of four metal-organic frameworks for adsorption desalination

The adsorption desalination cycle is a promising technique to address water scarcity. However, its production rate is low due to the low capacity of adsorbent materials. In this study, four metal organic frameworks namely aluminum fumarate, MOF–801, MIL–100(Fe), and CAU–10 H are synthesized and characterized and are tested for an application in adsorption desalination. After synthesizing the adsorbents, powder x-ray diffraction patterns for the samples are obtained to ensure a successful synthesis. The samples then undergo thermogravimetric water adsorption measurements at three different temperatures of 30 °C, 50 °C, and 70 °C at varying evaporator pressures. The water adsorption isotherms are also correlated with the Sun-Chakraborty adsorption isotherm model. It is found that the maximum water uptakes of aluminum fumarate, MOF–801, MIL–100(Fe), and CAU–10 H are 0.47, 0.35, 0.72, and 0.31 kg of water/kg of adsorbent, respectively. The highest water uptake of MIL–100(Fe) is due to its largest BET surface area and pore volume of 1634 m2/g and 0.47 m3/g, respectively. Consequently, MIL–100(Fe) provides the highest specific daily water production for adsorption desalination. Adsorption desalination cycles using MIL–100(Fe) could produce 2.2 and 2.3 times the freshwater obtained employing silica gel and CAU–10 H, respectively, with a heat recovery loop between the evaporator and condenser sections.

Experimental and computational study on utilising graphene oxide for adsorption cooling and water desalination

The adsorbent material’s thermal and sorption characteristics are the critical criteria that affect the adsorption systems’ overall performance. Therefore, this paper experimentally and computationally studies the utilisation of graphene oxide of a few atomic layers as a parent adsorbent material owing to its reported high thermal performance potential. Graphene oxide performance was benchmarked against the widely investigated silica gel adsorbent, emphasising adsorption cooling cum desalination application as the most needed to address the lack of sustainable cooling and clean water scarcity. Quantitative and qualitative analyses were undertaken to determine the influence of the evaporator temperature, cycle time and heat source temperature on the material and system levels. The results showed that graphene oxide enhances thermal performance by 44% compared to silica gel and adsorption by up to 57%. Furthermore, graphene oxide, compared to silica gel as a parent adsorbent, enhanced the system’s specific daily water production by up to 44.4%, the specific cooling power by up to 29.5%, the coefficient of performance by up to 17.2% and the exergy efficiency by up to 15.8%.

Improved adsorption desalination performance of DUT-67 by incorporating Graphene Oxide (GO)

Metal-organic frameworks (MOFs) have been recognized as one of the most promising adsorbents for adsorption desalination system (ADs) owing to their ultrahigh surface area. DUT-67 is a water-stable MOF with superior adsorption capacity, which has been demonstrated as a potential candidate for ADs. To further improve its desalination performance, in this work, different amounts of graphene oxide (GO) was incorporated with DUT-67 to obtain DUT-67/GO composites. The adsorption desalination performance including specific daily water production (SDWP) and performance ratio (PR) of DUT-67/GO composites under varying operating conditions were estimated by a lumped-parameter model. It is found that the mesopores in DUT-67/GO composites are favorable for the mass transfer. Among various DUT-67/GO composites, the DUT-67/GO composite with 24 wt% GO addition (DG-24) exhibited the highest water uptake (0.34 g/g) and overall mass transfer coefficient (0.0019 s−1), which were increased by 12.4% and 15.1% compared to DUT-67. Moreover, the average SDWP (14.7 m3/(ton/day)) and PR (0.77) of DG-24 were significantly improved by numerical simulation compared with DUT-67 (SDWP = 12.8 m3/(ton/day), PR = 0.72), which can be ascribed to their increased pore size and mass transfer coefficient.

Performance evaluation of a novel integrated adsorption desalination system with direct contact membrane distillation plant

Since adsorption desalination (AD) technology has low performance, a hybrid adsorption desalination system with a direct contact membrane distillation plant (AD-DCMD) is proposed for enhanced water production and reduced water cost. In addition to the desalination process, the cooling effect is also produced as a by-product of air conditioning. Two AD-DCMD configurations are investigated, in which the heat released from the AD condenser (configuration 1) and the adsorption process (configuration 2) are utilized to drive the DCMD system. The main performance parameters, such as gain output ratio (GOR), specific daily water production (SDWP), freshwater cost, and coefficient of performance (COP), are investigated. The influential operating parameters are tuned to obtain optimal performance. Results show that GOR values reach 1.48 and 1.6 for configurations 1 and 2, respectively, which is more than the AD system by >117 %. For configuration 2, the SDWP reaches 53 m3/ton per day, higher than the AD system by 136.7 %, at an operating temperature of 90°C. COP was found to be 0.76 and 0.70 for configurations 1 and 2, respectively. Moreover, the freshwater cost of configurations 1 and 2 is 1.72 and 0.92 $/m3, with a reduction of 18.03 and 56.05 %, respectively, compared to the AD system.

Evaluation on the performances of adsorption desalination employing functionalized metal-organic frameworks (MOFs)

• Isotherms and kinetics data for water adsorption on functionalized MOFs. • Equations of entropy flow and generation for evaluating AD performances. • Measurement of structural and thermal stabilities of functionalized MOFs. • Calculation of SDWP and PR by temperature-entropy analysis for the first time. • 5%Li-Al-Fum shows minimum entropy generation with higher SDWP. This study focuses on a comprehensive study of MOFs (metal-organic frameworks) plus water systems for adsorption desalination applications. The paper first deals with the modification of parent MOFs such as aluminium fumarate, MOF-801 (Zr) and UiO-66 (Zr) employing MOFs functionalization, alkali ion doping and impregnation of zeolites, and secondly, we focus on their characterizations for understanding both structural and thermal stabilities. Later, water adsorption on these parents and modified MOFs are investigated for a wide range of pressure (0 < P/P s < 1.0) and temperature (30 to 80 °C). Based on experimentally confirmed isotherms, kinetics and MOFs characteristics data, the performance factors such as SDWP (specific daily water production) and PR (performance ratio) are evaluated for various regeneration temperature (55 to 80 °C) and cycle time (100 to 1000 s). Furthermore, the water adsorption characteristics are applied to calculate the entropy flow and generation for each component of AD system. The SDWP is also calculated from the concepts of temperature – entropy diagram. It is found that both OH-UiO-66 (Zr) and 5%Li-Al-FumMOFs provide promising SDWP (> 34 m 3 /tonne of MOFs/day) and 5%Li-Al-Fum shows minimum entropy generation.

Performance analysis of a lab-scale adsorption desalination system using silica gel/LiCl composite

Adsorption desalination is a novel technology to supply high-quality potable water driven by a low-temperature heat source. However, only a few composite sorbents, whose excellent performances have been demonstrated in other adsorption-based systems, have been applied in adsorption desalination (AD) systems. This study evaluated the performances of LiCl-silica gel (30 % wt) composite in a lab-scale AD system, realized by packing the sorbents beads inside a finned flat-tube heat exchanger. For the first time, the ad/desorption dynamics under various operating conditions were measured using a T-LTJ (thermal-large temperature jump) apparatus, which has not been employed for evaluation of desalination prototypes so far. The sorption dynamics was compared with silica gel, which is a standard material for AD systems. Results were used to calculate the maximum specific daily water production (SDWP) and optimized cycle time. Moreover, three design strategies of the AD system were proposed, including 2-beds, 3-beds and 4-beds. The 3-beds-configuration was selected for the composite sorbent, being able to reach an SDWP as high as 69 m3/tonne/day under the condition of Teva/cond = 20 °C and Tde = 80 °C. The optimized cycle time is dependent on operating conditions, varying in the range of 240–470 s.

Recent development in adsorption desalination: A state of the art review

Adsorption desalination is prescribed as a promising and eco-friendly solution for mitigating water scarcity, owing to its utilization of low-grade thermal waste and zero liquid brine discharge. The keystones that regulate the performance of the adsorption desalination system (ADS) include nature of adsorbents, system design, and operating conditions. The present study aims to provide a state of the art review on the keystones of ADS. Metal-organic frameworks (MOFs) hold remarkable adsorption capacity and tunable structure. However, hydrothermal instability, high cost, and complex synthesizing procedures are the potential challenges that need to be addressed. The technological advancements in ADS have been classified into: (i) Conventional Approach, (ii) Heat and Mass Recovery Approaches, (iii) Hybridization Approaches, (iv) and Adsorbent Substituting Approach. The study provides critical insight and compares the performance of each approach based on specific daily water production (SDWP), specific cooling power (SCP), and coefficient of performance (COP). The conventional ADS produce SDWP of 4.7 m3/ton/d, however producing zero and/or minimal SCP while using payable energy of 1.50 kWh/m3. In heat/mass recovery approaches, pressure equalization-valve delay schemes and master–slave configuration provide ∼ 5 % additional water adsorption/desorption on/from silica-gel and reduce ∼ 50 % thermal heating load, respectively. Evaporator-condenser amalgamation emphasizes the evaporator temperature of 30–42 °C leading towards ∼ 69 % higher SDWP with zero SCP. Dual stage, multi evaporators/condensers scheme is found supportive in cogenerating feature of ADS thereby improvising COP to ∼ 0.87. In hybridization approach, ejector integrated ADS produces SDWP of 80 m3/ton and COP of 2.22 using payable energy of 0.92 kWh/m3, however, needs experimental validation. In the adsorbent substituting approach, CPO-27(Ni), Emim-Ac/Syloid 72FP, and composite adsorbent manifest the SDWP to higher levels. The operating conditions are sensitive and need to optimize depending on the configuration of ADS. Possible future research directions may include efficient designing/ sizing of evaporators/ condensers, minimizing the heat and mass transfer resistances in adsorber/desorber reactor, optimize the thickness of the adsorbent layer in heat exchangers, and investigating wide range of adsorbent classes that can be driven with very low regeneration temperature.

Theoretical evaluation of adsorption desalination performance of metal-organic frameworks under varying scenarios

• Adsorption desalination performance of 12 adsorbents was evaluated. • MOFs outperform other adsorbents owing to their higher water transfer amount. • Desalination performance of adsorbents is correlated with adsorption characteristics. • DUT-67 is the most potential candidate under varying operation conditions. Adsorption desalination systems (ADs) driven by low-grade energy are regarded as sustainable alternatives to address water shortages due to their low energy consumption. Adsorbents is the key materials for the performance of ADs. In this work, a numerical study was performed to assess the water production performance of ADs based on metal–organic frameworks (MOFs) and other adsorbents under different working conditions. It is found that the trends in specific daily water production (SDWP) and performance ratio (PR) with hot and chilled water temperature are closely correlated with the adsorption characteristics, i.e., water uptake and the shape of adsorption isotherms. Moreover, considering both SDWP and PR, MOFs outperform other adsorbents owing to their high water transfer amount per cycle under various conditions. Among 12 adsorbents, DUT-67, Al-fumarate and MIL-100(Fe) are the top performers at chilled water temperature of 10 °C, 20 °C and 30 °C respectively with average SDWP (PR) of 3.31 m 3 /ton/day (0.33), 8.05 m 3 /ton/day (0.56) and 13.46 m 3 /ton/day (0.71), increased by 43.8% (32.0%), 65.3% (40%), and 102.7% (44%) compared to traditional silica gel. This work provides helpful insights into the correlation between desalination performance and water adsorption characteristics of adsorbents under varying working conditions, which favors choosing and designing of potential adsorbents for ADs.

Solar powered adsorption desalination system employing CPO-27(Ni)

Adsorption-based desalination system (ADS) is an alternative technology to the traditional water desalination systems as low-temperature sources can operate it. Also, ADSs use environmentally friendly materials, limiting global warming and environmental pollution. This work investigates the performance parameters of ADS powered by an evacuated thermal solar collector theoretically and experimentally. The system uses an advanced sorption material of metal-organic frameworks called CPO-27(Ni). The study estimates optimal operating conditions of ADS under the climate of Egypt. A mathematical model is carried out using MATLAB integrated with TRNSYS software. The study investigates high system performance through two modes; without heat recovery (Mode-1) and heat recovery (Mode-2). The ADS performance is evaluated by specific daily water production (SDWP) and gain output ratio (GOR) parameters. The results show a remarkable superiority for mode-2 as it achieved 10 (m3/ton-day) SDWP and 0.4 GOR, while mode-1 achieved about 5 (m3/ton-day) SDWP and 0.23 GOR at the optimum operating conditions. The improvement ratio using mode-2 reached 88 % of SDWP and 79 % of GOR. Also, the validation results showed a good qualitative and quantitative agreement between the experimental and theoretical data.

Performance investigation of adsorption cooling and desalination systems employing thermally enhanced copper foamed bed coated with SAPO-34 and CPO-27(Ni)

Despite the increasing interest in adsorption cooling and desalination systems, the poor heat hence mass transfer in the adsorbent-bed (the core component) impedes the efficient energy conversion at the system level and increases its physical footprint. In response, this paper numerically investigates the overall enhancement of adsorption cooling cum desalination system employing emerging copper foamed adsorbent beds of advanced thermal performance coated with advanced adsorbent materials to address such an untapped challenge. Silico-aluminophosphate (SAPO-34) and Nickel-based metal-organic framework CPO-27(Ni) adsorbents were employed. First, a 2-D axisymmetric computational fluid dynamic fully coupled model was developed to simulate the adsorbent-beds considering non-ideal condenser and evaporator pressures. Second, the influence of different operating conditions and copper foam thicknesses was investigated at the adsorbent-bed and system levels. The advanced adsorption kinetics of SAPO-34 enabled shortening the cycle time from 600 to 180 s, which enhanced the coefficient of performance (COP), specific cooling power (SCP), and specific daily water production (SDWP) of the system by 163%, 223%, and 228%. The regeneration temperature was the most influential parameter on the systems’ performance within the investigated range (70–100 °C). It enhanced the COP from 0.2 to 0.421, SCP from 132 to 821 W.kg−1, and SDWP from 4.7 to 29.3 m3.ton-1.day−1, for CPO-27(Ni) coated bed; and COP from 0.378 to 0.388 and SCP from 393 to 855 W.kg−1 and SDWP from 14 to 31 m3.ton-1.day−1 , for SAPO-34 coated bed. The reported enhancements at the adsorption system-level signpost metal-foamed adsorbent-bed coating the most thermally efficient adsorbent-bed design.

Coated, packed and combined wire finned tube adsorption cooling and desalination system using metal-organic framework: Numerical study

The adsorber bed design and the method of integrating the adsorbent material in the bed have a major effect on the overall performance of the adsorption system. This study numerically investigates the performance of wire finned tube adsorber bed with aluminium fumarate metal-organic framework material integrated either using coating, packing, or combination of coating and packing. A 3D heat and mass transfer model using the coupled solution approach with a variable vapor pressure through the adsorbent voids between the particles is developed. Results showed that the coated wire finned heat exchanger outperforms the packed and the combined packed and coated in terms of the specific daily water production (SDWP) and specific cooling power (SCP). Also, a parametric study was carried out of the coated wire finned heat exchanger geometry including different tube diameters, fin height, and number of fins to predict the best geometrical parameters that produce maximum output using different coating thicknesses. Results revealed that using tube diameter of 22 mm, fin height of 20 mm, 44 fins per loop, and coating thickness of 0.5 mm can provide maximum water daily water production of 300 L/day and cooling power of 8.3 kW.

Development and characterization of LiCl supported composite sorbents for adsorption desalination

• Two innovative composite sorbents were developed for sorption desalination. • Thermodynamic and kinetic performance at material level were deeply investigated. • LiCl/Silica gel composite showed a maximum SDWP higher than 60 m 3 /tonne/day. Adsorption desalination (AD) is an emerging technology to reduce risk of freshwater scarcity, able to use renewable energy and applicable in decentralized areas. Only limited sorbents have been tested experimentally for AD systems. This study developed two composite sorbents based on LiCl as embedded salt and two matrices, namely, silica gel (LiCl@SG_30) and expanded vermiculite (LiCl@EVM_45). The performed analysis figured out how the trade-off between high sorption capacity and good mass transfer caused by their different pore structures influences the desalination operations. The results were compared against a standard microporous Siogel. The sorption isobars indicated that the sorption behavior of LiCl@SG_30 is the combination of silica gel and the embedded LiCl crystals, while for LiCl@EVM_45 is mainly the sorption process of the embedded LiCl crystals. LiCl@EVM_45 reached the highest sorption capacity. The Dubinin-Astakhov equation described the equilibrium capacities of the sorbents. The kinetics coefficient ( k ) was employed to evaluate the sorption rate. Microporous Siogel showed the highest sorption rate, followed by LiCl@SG_30 and LiCl@EVM_45. Finally, predicted specific daily water production (SDWP) were calculated, showing promising features for both LiCl@SG_30 and LiCl@EVM_45, with LiCl@SG_30 achieving SDWP ranging from 43 to 60 m 3 /tonne/day) for the selected conditions.

Applicability assessment of functional adsorption zeolite materials in adsorption desalination cum cooling systems driven by low-grade heat source

• Thermophysical properties of the FAM-Z series were evaluated using argon adsorption isotherms. • Modified Do–Do and hybrid Langmuir–Sips isotherm models were proposed. • AD cycle performance was evaluated in terms of SDWP, SCC, COP, and PR. • AFI-type zeolite has shown its applicability to residential and district cooling. • FAM-Z05 can be used for AD cycles driven by an extremely low-grade heat source (<55 °C). This study provides an in-depth analysis of the sequence of procedures required to evaluate the performance of adsorption desalination (AD) using functional adsorbent material zeolites (i.e., FAM-Z series with AFI and CHA types). The applicability of zeolite as an adsorbent for the AD cycle was also demonstrated by comparing it with the performance of AD using silica gel. The adsorption isotherm of the adsorbent, which is the most important parameter in the performance and design of the AD cycle, is recognized as a crucial parameter that significantly affects the AD performance. The thermophysical properties of the FAM-Z series were analyzed using argon adsorption and desorption isotherms at 87 K, followed by water vapor adsorption isotherms. Modified Do–Do and hybrid Langmuir–Sips isotherm models were proposed and are suitable for the anomalous stepwise isotherms of the FAM-Z series and the mesoporous adsorption characteristics of silica gel. The performance of the AD cycle was assessed in terms of the specific daily water production, specific cooling capacity, coefficient of performance, and performance ratio with respect to chilled and hot water temperatures and cycle times using a mathematical model of the AD cycle validated through a comparison with experimental data. AFI-type zeolites showed the applicability of residential (FAM-Z01) and district cooling (FAM-Z05), which have a low regeneration temperature of 55 ℃ owing to an unusual isotherm (i.e., sigmoid adsorption isotherm). In addition, FAM-Z05 exhibited considerable potential as an adsorbent for AD cycles driven by extremely low-grade heat sources (<55 °C) found in industrial plants and solar energy.

Numerical and experimental investigation of multiple heat exchanger modules in cooling and desalination adsorption system using metal organic framework

The cooling and desalination adsorption system is a heat-activated system based on the solid sorption process. The main challenge in this system is concentrated to decrease the energy consumption of this system using a low desorption temperature (less than 90 °C) while maintaining a good performance. A scaled-up adsorption system using multiple heat exchanger modules packed with commercially available metal–organic framework material that operates at low desorption temperature, was numerically and experimentally investigated in the present paper. Three-dimensional and two-dimensional axisymmetric numerical models were developed to simulate heat and mass transfer phenomena considering the internal and external mass transfer in the adsorbent domains. Effects of the modules' connection options and vapor gap between modules on the system performance were examined. The highest coefficient of performance was achieved when connecting the modules in series, affected by the considerable reduction in the heating power. However, the increase in the effective amount of adsorbate resulted in the best specific cooling power when connecting the modules in parallel. Additionally, A scaled-up adsorption cooling/desalination system using 23.2 kg of Aluminium Fumarate packed in 16 modules was constructed and evaluated experimentally. The system produced desalinated water of 201 L/day and cooling capacity of 5.25 kW at the evaporator, condenser, and desorption water temperatures of 24 °C, 25 °C, and 85 °C, respectively. The specific daily water production decreased by 16.3% when the water salinity increased from 90 to 100,000 ppm, while the lowest specific electrical energy consumption of the proposed system is 1.87 kWh/m3. The theoretical and experimental results will enable further scaling up of an efficient MOF adsorption system for cooling and water desalination.