Kg Of Ice Research Articles

Research on the characteristics of photovoltaic-driven refrigerated warehouse with ice storage in field under weather and load variation

The field photovoltaic refrigerated warehouse works well in pre-cooling and refrigerating fruits and vegetables in remote areas. Thus, it is crucial to ensure its long-term stable operation, particularly under the dual challenges of fluctuating solar energy supply and the unstable energy consumption required for load variation. This paper investigates the operational characteristics of a 1.5-ton photovoltaic-driven refrigerated warehouse with ice storage under varying loads and weather conditions. Results indicate that the average cooling time of the material was 26 h, under the condition of continuous material inflow into the warehouse. Additionally, 26 kg of ice were produced per day per kilowatt of solar panel capacity. Energy requirements of the device for 1.1 nights match its daily ice production. Furthermore, a maximum COP of 0.34 was achieved under photovoltaic drive. The internal temperature of the load was effectively maintained within the range of 3–4 °C, even during consecutive overcast and rainy weather. Based on this, an 8-ton field photovoltaic-driven refrigerated warehouse with ice storage was constructed. These studies provide an effective alternative refrigeration solution for remote regions, addressing their cooling needs efficiently.

Studi Perbandingan selenoid kapiler dan selenoid ekspansi pada Mesin Es serta di kontrol Aplikasi Blynk

Currently, the use of this ice machine still uses a solenoid connected to a capillary and the results cannotbe targeted. The use of an ice machine with the ESP8266 module is combined with the blynk applicationwhich is a combination with the Internet of Thinks (IoT) system which makes the performance of using theice machine can be run remotely or with a smartphone. Reduced costs and less operator effort to expendfor ice making. The ice machine was finally integrated with the ESP8266 Module, the blynk applicationand added with one solenoid connected to an expansion which functions as a substitute for the capillaryselenoid if the need for ice is needed quickly in the process and will return to the capillary selenoid duringnormal production. The results showed that the ice machine with capillary selenoid was slower in the iceproduction process with 1 hour of production time of 5 kg of ice and required electricity consumptionduring production of 0.814 KWH, while the ice machine after using selenoid expansion the machineproduction process was faster than the capillary selenoid system by producing ice production for 1 hourwith a yield of 8 kg of ice and requires electricity consumption during production of 0.855 KWH, withpressure for expansion of 18 bar.

Performance Assessment of an Ice-Production Hybrid Solar CPV/T System Combining Both Adsorption and Vapor-Compression Refrigeration Systems

The technology of a hybrid solar concentration photovoltaic/thermal (CPV/T) system is an efficient way of converting solar energy to heat and electrical power, in which overall energy-extraction efficiency is at its highest. In this study, numerical dynamic simulation models were developed for a hybrid solar CPV/T system and an adsorption refrigeration system (ARS). Under the climatic conditions of Riyadh all year round, the electrical and thermal powers generated by the CPV/T system were used to estimate the ice production of both the vapor compression refrigeration system (VCS) and the ARS. The CPV/T system can provide a thermal energy of 37.6 kWh and electrical energy of 24.7 kWh a day on average over the year using a 12.5 m2 facing area of Fresnel lenses. The ARS employed an advanced approach which used Maxsorb III adsorbent packed in two aluminum foam beds. An optimum cycle time of the ARS was adapted for each month to match the variation in the thermal energy, while a variable-speed compressor was chosen for the VCS. Due to its higher coefficient of performance (COP), the proposed solar hybrid system can produce 494.4 kg of ice per day while sharing 84.5% of the VCS. The average solar COP over the year of the hybrid system can attain 0.875, which represents a promising value for a solar ice-production system.

Numerical Simulation and Optimization of a Solar Adsorption Icemaker

A solar adsorption ice maker was numerically studied. The system is an adsorption cycle that is connected to a separate solar heating system. An oil solar collector is connected to the generator of the adsorption cycle through a heat-exchanger in a closed loop. A refrigeration pair of Methanol-Activated Carbon (AC) was considered in the adsorption cycle. A mathematical model was developed for each component of the system. A transient numerical simulation was established, and the annual system performance was demonstrated under weather conditions of Makkah city, 21.5 ⸰N. The system unique design was achieved, and the ideal mass was predicted for the adsorbent and adsorbate together maintaining a constant percentage between them. It is found that the system which apply the Activated carbon/Methanol YKAC (14-20 MESH) might possibly deliver high solar system performance (SCOP) of about 0.26 during the cold days and 0.367 of cycle. As expected, lower temperature of the condenser and higher temperature of the evaporator can improve the system COP. In addition, three different kinds of collectors were considered and the maximum efficiency of about 0.80 was achieved for flat plate at optimum area of 3.15 m2 which is higher than both evacuated-tube (ETC) and parabolic trough collector (PTC) all over the year. The ETC efficiency is about 0.71 at ideal collector area of 3.5 square meters while the optimum area of the parabolic trough is 8.4 m2 at 0.79 of efficiency. In conclusion, the system results recommended that 22kg of ice could be produced every day for each square meter of solar collector.

A Low-Cost, Easy-to-Assemble Device to Prevent Infant Hyperthermia under Conditions of High Thermal Stress.

High ambient temperature and humidity greatly increase the risk of hyperthermia and mortality, particularly in infants, who are especially prone to dehydration. World areas at high risk of heat stress include many of the low- and middle-income countries (LMICs) where most of their inhabitants have no access to air conditioning. This study aimed to design, evaluate, and test a novel low-cost and easy-to-assemble device aimed at preventing the risk of infant hyperthermia in LMICs. The device is based on optimizing negative heat transfer from a small amount of ice and transferring it directly to the infant by airflow of refrigerated air. As a proof of concept, a device was assembled mainly using recycled materials, and its performance was assessed under laboratory-controlled conditions in a climatic chamber mimicking realistic stress conditions of high temperature and humidity. The device, which can be assembled by any layperson using easily available materials, provided sufficient refrigerating capacity for several hours from just 1–2 kg of ice obtained from a domestic freezer. Thus, application of this novel device may serve to attenuate the adverse effects of heat stress in infants, particularly in the context of the evolving climatic change trends.

Performance characteristics of mobile cooling system utilizing ice thermal energy storage with direct contact discharging for a refrigerated truck

The objective of this study if to investigate the performance characteristics of the mobile cooling system including an ice-making unit (IMU) for charging and a mobile air-cooling unit (MCU) for discharging. The performance of a mobile cooling system using ice thermal energy storage for direct contact discharge in refrigerated trucks was investigated and discussed by varying the amount of ice, ice cube mass, face air velocity, and inlet air temperature used. . In the IMU, the average coefficients of performance(COP) decreased with the increasing ice cube mass. The average COP of an ice cube of 6.8 g was 28.5% higher than that for an ice cube of 10.0 g. In the MCU, the maximum COPs were found at a face air velocity of 1.28 m s−1 and ice mass of 6.0 kg. The effect of the ice cube on the COP varied according to the amount of ice. in the integrated system of IMU and MCU, the mass of an ice cube was dominant in the power consumption of the IMU and the fan power consumption in the MCU. Accordingly, at 10 °C for 10.00 kg of ice, the modified total COP for 10.0 g was 11.5% lower and 21.7% higher at the target cooling capacity of 0.20 kW and 0.51 kW, respectively, than that for 6.8 g.

Energy, exergy, exergoeconomic, and economic analysis of a novel power generation cycle integrated with seawater desalination system using the cold energy of liquified natural gas

Utilizing the cold energy of liquefied natural gas can reduce the demand of burning fossil fuels for work production and employing refrigeration cycles for seawater desalination. A novel low-temperature cascade power generation cycle combined with a seawater freeze desalination system is proposed to retrieve the cold energy from liquified natural gas. Binary working fluids are utilized to decrease the irreversibilities of the power cycle and enhance the energy recovery efficiency. The effects of the important temperatures of the cycle, pinch temperature of the heat exchangers, number of turbines and their efficiency on the cycle performance are investigated. Optimization of the work production showed that the cycle could achieve 105 kW per unit mass of liquified natural gas while increasing its temperature to −47.48℃. An exergoeconomic model is developed to assess the exergy costs of the system operation and minimize the sum of the unit of production cost. A multi-objective optimization is conducted to maximize the work production and minimize the production costs. Results show that the cycle has the best performance while working at its exergoeconomic optimal point. Using the same amount of cold energy that was used for producing a particular work in the literature, the current system can produce 0.537 to 0.441 kg of ice along with generating the same work. Using the remaining cold energy of liquified natural gas for work production in another stage in series with the cycle instead of exploiting it in a freeze desalination system would increase the work production between 5.7% and 9% compared to the literature. Although this leads to an addition of 6.7% to the work production of the cycle, the payback period increases by 25%. Hence, from economical point of view, dedicating a specific portion of the cold energy of liquified natural gas for freeze desalination is more effective than using the entire cold energy for work production. Thus, a limit for the maximum temperature of liquified natural gas should be considered at the exit of the cycle for more efficiency.

Anak Krakatau triggers volcanic freezer in the upper troposphere

Volcanic activity occurring in tropical moist atmospheres can promote deep convection and trigger volcanic thunderstorms. These phenomena, however, are rarely observed to last continuously for more than a day and so insights into the dynamics, microphysics and electrification processes are limited. Here we present a multidisciplinary study on an extreme case, where volcanically-triggered deep convection lasted for six days. We show that this unprecedented event was caused and sustained by phreatomagmatic activity at Anak Krakatau volcano, Indonesia during 22–28 December 2018. Our modelling suggests an ice mass flow rate of ~5 × 106 kg/s for the initial explosive eruption associated with a flank collapse. Following the flank collapse, a deep convective cloud column formed over the volcano and acted as a ‘volcanic freezer’ containing ~3 × 109 kg of ice on average with maxima reaching ~1010 kg. Our satellite analyses reveal that the convective anvil cloud, reaching 16–18 km above sea level, was ice-rich and ash-poor. Cloud-top temperatures hovered around −80 °C and ice particles produced in the anvil were notably small (effective radii ~20 µm). Our analyses indicate that vigorous updrafts (>50 m/s) and prodigious ice production explain the impressive number of lightning flashes (~100,000) recorded near the volcano from 22 to 28 December 2018. Our results, together with the unique dataset we have compiled, show that lightning flash rates were strongly correlated (R = 0.77) with satellite-derived plume heights for this event.

Temperatures limitation of adsorptive solar powered ice maker using AC35-methanol pair

A numerical evaluation of temperatures limits of solar adsorption refrigeration machine cycle using the AC35-methanol pair is presented in this paper. The cold production was better for lower adsorption temperatures and higher temperatures of evaporating and generating. For each 1 kg of adsorbent, 1 kg of ice can be produced for temperatures of generating from 40°C to 100°C according to solar irradiance and ambient temperature. The considered lower adsorption temperature is 10°C, which can allow to produce 9 kg of ice for higher temperatures of generating up to 130°C, this needs 680 kJ of solar irradiance for surface area of 1 m2 of solar collector. The considered higher evaporating temperature is 10°C, which can allow to produce 3.5 kg of ice for higher temperatures of generating up to 144°C, this needs 622 kJ of solar irradiance for surface area of 1 m2 of solar collector.

Experimental study on a new solar refrigerator with intermittent adsorption cycle

This paper presents experimental results for a prototype intermittent solar adsorption ice-maker using water as the refrigerant and silica gel as the adsorbent. Four external flat reflectors made of polished stainless steel were used to enhance the performance. On a cloudy day, without reflectors, a minimum temperature of 7 °C was reached, so no ice was made. With reflectors 0.5 kg of ice was made from a 9 kg load. Increasing the load of water tended to increase the solar COP. The effect of the initial mass of refrigerant was also investigated.

Design and Analysis of a Solar Driven Vapour Absorption Refrigeration System as an Alternative to Solar PV Powered Refrigerators

There exists an immense need around the world for refrigeration capabilities where the infrastructure of dependable power does not exist. In this study, the concept of a flat plate collector for an intermittent ammonia absorption refrigeration system is analyzed. The design is juxtaposed against a solar photo-voltaic powered refrigerator to evaluate its feasibility. Relevant design equations, codes, standards and procedures were integrated to develop a system that would boil off approximately 0.34kg of ammonia from 0.553kg of calcium chloride capable of producing 0.91kg of ice. The results showed that a collector area of 0.93m² was needed to produce the 782.4kJ of heat required, the required condenser volume was calculated to be 28.4 liters, and the evaporator volume to hold the ammonia calculated to be 0.51 liters (Length = 0.4 m, D = 40 mm). The copper fin – steel pipe stress due to thermal expansion of the system was calculated to be 59.159 MPa which was below, 249.944 MPa, the maximum allowable stress of the material. The system was designed to have a maximum operating pressure of 9653 kPa. In a test, the final prototype attained consistent generator temperatures in the 364 - 378K range and once switched to the “night cycle” attained evaporator temperatures in the 0°C to -7°C range thus confirming the concept of the flat design (the primary objective) as well producing consistent evaporator temperatures below 0°C (the secondary objective).

Design and analysis of a flooded tube for cold energy storage

Energy storage systems provide the methods and technologies used to store energy of various forms. Cold thermal storage is used to store energy during off-peak load conditions for later use during peak load conditions. A flooded tube for cold thermal storage was built to study the formation of ice experimentally. The flooded tube was subjected to stagnant water, stirred water, and recirculated water. The flooded tube with recirculated water showed the best performance. About 7.9 g/m2 s of ice was formed with a starting overall heat transfer coefficient of 1096 W/m2 K. Discharge cycles were analyzed, and it was determined that 7.1 kg of ice was sufficient to hold a load for 110 min for a 927 W unit.

Falling water ice affinity purification of ice-binding proteins

Ice-binding proteins (IBPs) permit their hosts to thrive in the presence of ice. The ability of IBPs to control ice growth makes them potential additives in industries ranging from food storage and cryopreservation to anti-icing systems. For IBPs to be used in commercial applications, however, methods are needed to produce sufficient quantities of high-quality proteins. Here, we describe a new method for IBP purification, termed falling water ice affinity purification (FWIP). The method is based on the affinity of IBPs for ice and does not require molecular tags. A crude IBP solution is allowed to flow over a chilled vertical surface of a commercial ice machine. The temperature of the surface is lowered gradually until ice crystals are produced, to which the IBPs bind but other solutes do not. We found that a maximum of 35 mg of IBP was incorporated in 1 kg of ice. Two rounds of FWIP resulted in >95% purity. An ice machine that produces 60 kg of ice per day can be used to purify one gram of IBP per day. In combination with efficient concentration of the protein solution by tangential flow filtration the FWIP method is suitable for the purification of grams of IBPs for research purposes and applications.

Experimental study of solar powered ice maker using adsorption pair of activated carbon and methanol

The present study introduces an experimental work for a solar adsorption ice maker system (SAIMS) using working pair of activated carbon (AquaSorb 2000) and methanol. The isotherm and isobar characteristics of the used pair are investigated by using Dubinin-Raduskevich (D-R) equation then, the SAIMS is constructed and tested at real weather conditions of Qena, Egypt. The findings of the pairs reveal that it suitable for the solar adsorption ice making applications with adsorption capacity found to be 0.6935 kg of methanol per kg of activated carbon (AquaSorb 2000). The constructed SAIMS can produce about 0.4 kg of ice per kg of AquaSorb 2000 by using the acrylic sheets in the adsorption bed instead of glass or other bed covers. Also, the experimental results proved that by using the acrylic sheets with a good design of the adsorption bed and due to the enhancement of heat transfer and high adsorbent temperature, the mass of desorbed methanol and produced ice is increased. Therefore, both gross and net COP are improved in comparison with other previous studies with single, double and Transparent Insulation Material (TIM) in the adsorber.

Adsorption Refrigeration System: Design and Analysis

Cooling systems like vapour absorption or vapour adsorption refrigeration system, which runs on low grade energy sources provide favourable alternatives to the conventional vapour compression refrigeration system .These system do not contribute to global warming,depletion of fossil fuel or ozone layer depletion as there is absence of conventional mechanical compressor and use of Eco-friendly refrigerant. This cycle can utilize low grade heat sources like,waste heat of flue gases,Automobile vehicle exhaust,or even solar energy and hence has much scope of development in the near future .The work include design,development and analysis of Adsorption Refrigeration System which is capable of producing 10-15 kg of ice in each cycle,and does not contain any moving part and maintenance free.

Thermal analysis and modeling study of an activated carbon solar adsorption icemaker: Dhahran case study

Intermittent adsorption refrigeration systems are suitable for producing ice in remote areas. EES and MATLAB computer programs are exploited to analyze the thermodynamic cycle and to model the system under Dhahran climate conditions, respectively. The results show that the system performance in winter is better than in summer under the climate conditions for the city of Dhahran, Saudi Arabia. For example, the system produces below 3kg in the hot days and more than 5kg of ice per square meter of solar collector in the cold days with solar coefficient of performance (SCOP) that varies between 0.077 and 0.17, respectively.

Improving accuracy and precision of ice core δD(CH<sub>4</sub>) analyses using methane pre-pyrolysis and hydrogen post-pyrolysis trapping and subsequent chromatographic separation

Abstract. Firn and polar ice cores offer the only direct palaeoatmospheric archive. Analyses of past greenhouse gas concentrations and their isotopic compositions in air bubbles in the ice can help to constrain changes in global biogeochemical cycles in the past. For the analysis of the hydrogen isotopic composition of methane (δD(CH4) or δ2H(CH4)) 0.5 to 1.5 kg of ice was hitherto used. Here we present a method to improve precision and reduce the sample amount for δD(CH4) measurements in (ice core) air. Pre-concentrated methane is focused in front of a high temperature oven (pre-pyrolysis trapping), and molecular hydrogen formed by pyrolysis is trapped afterwards (post-pyrolysis trapping), both on a carbon-PLOT capillary at −196 °C. Argon, oxygen, nitrogen, carbon monoxide, unpyrolysed methane and krypton are trapped together with H2 and must be separated using a second short, cooled chromatographic column to ensure accurate results. Pre- and post-pyrolysis trapping largely removes the isotopic fractionation induced during chromatographic separation and results in a narrow peak in the mass spectrometer. Air standards can be measured with a precision better than 1‰. For polar ice samples from glacial periods, we estimate a precision of 2.3‰ for 350 g of ice (or roughly 30 mL – at standard temperature and pressure (STP) – of air) with 350 ppb of methane. This corresponds to recent tropospheric air samples (about 1900 ppb CH4) of about 6 mL (STP) or about 500 pmol of pure CH4.

THE EVOLVING ACTIVITY OF THE DYNAMICALLY YOUNG COMET C/2009 P1 (Garradd)

We used the UltraViolet-Optical Telescope on board Swift to observe the dynamically young comet C/2009 P1 (Garradd) from a heliocentric distance of 3.5 AU pre-perihelion until 4.0 AU outbound. At 3.5 AU pre-perihelion, comet Garradd had one of the highest dust-to-gas ratios ever observed, matched only by comet Hale-Bopp. The evolving morphology of the dust in its coma suggests an outburst that ended around 2.2 AU pre-perihelion. Comparing slit-based measurements and observations acquired with larger fields of view indicated that between 3 AU and 2 AU pre-perihelion a significant extended source started producing water in the coma. We demonstrate that this source, which could be due to icy grains, disappeared quickly around perihelion. Water production by the nucleus may be attributed to a constantly active source of at least 75 km$^2$, estimated to be more than 20 percent of the surface. Based on our measurements, the comet lost $4x10^{11}$ kg of ice and dust during this apparition, corresponding to at most a few meters of its surface.Even though this was likely not Garradd's first passage through the inner solar system, the activity of the comet was complex and changed significantly during the time it was observed.

Removal of nitrates from processing wastewater by cryoconcentration combined with biological denitrification

In this study, the treatment of wastewater with a high nitrate content was investigated using the method of cryoconcentration on a pilot scale. The initial nitrate concentration in the treated wastewater was at 1,500 mg N/l. During 40 h of cryoconcentration of the wastewater, 176.6 kg of ice was produced, corresponding to a total process efficiency of 4.42 kg/h of ice. The crystallization temperature decreased from −0.5 to −9°C during the process. The final concentration of nitrates in the concentrated product was at 37 g N/l, and the conductivity was at 158 mS/cm. The conductivity of the water obtained by melting the ice ranged from 0.98 to 1.4 mS/cm. Concentrates with initial nitrate concentrations of 3, 6, and 9 g N/l were then subjected to microbial denitrification. The values of the specific nitrate reduction rates ranged from 43.1 to 49 mg N/gVSS h.

A stand-alone solar adsorption refrigerator for humanitarian aid

Solar adsorption ice makers are devices which could prove a great help in sustaining the cold chain in third world countries. The use of such devices could be extended also in supporting humanitarian aid actions for vaccines storage. However, further development and optimization of the system design are still required. In this paper a new, versatile, solar driven ice maker operating with the activated carbon/methanol adsorption pair has been developed and tested. The field tests carried out on February and March 2013, showed that the prototype is able to produce up to 5kg of ice, with a solar Coefficient Of Performance (COPs) of about 0.08, and to preserve it for whole next day. The overall dimensions of the realized prototype are 1.7×1.5×0.95m. Solar radiation is collected by a solar collector with an exposed area of 1.2m2.