Major breakthrough!The big king Ruzhu team realizes a large number of production water in semi -arid areas

Recently, the ITEWA team led by Professor Ruzhu of Shanghai Jiaotong Published in Nature Communications, I published a paper entitled by the Exceptional Water Production Yield Enabled Portable Water Harvester in Semi-Anto Climate. The perspective of the operation mode has brought about the gap between adsorption and absorbing dynamics, and proposed a new type of "night-batches adsorption-day by day to solve the suction" batch-absorbing-relieving mode. At the same time, according to the careful heat transfer design of high -performance adsorbents and the water removal system, the portable air water removal system of this mode is used to realize the high extraction of 311.69 g of a single day in Lanzhou semi -drought climate (minimum relative humidity during the day) in Lanzhou, China Water volume. The first author of the paper is Shan Yan, a doctoral student of the Institute of Refrigeration and Low -temperature Engineering of Shanghai Jiaotong University.

Development and structure and parameter optimization of air water extraction device

The output of adsorption air is low, and it is difficult to make large -scale and commercialized use, mainly because it is subject to limited adsorption capacity of adsorbing materials under low humidity, rough system design, and without optimized operating mode. The article adopts the thermodynamic phase of lithium chloride-water-water-to-dynamic model and linear driving dynamic model to balance the prediction and optimization of absorbing dynamics to develop high-performance lithium chloride composite adsorbent materials. At the same time, in order to more accurately evaluate the actual adsorption performance in the actual semi -drought climate, the article indicates the adsorption and resolution performance of a large adsorption agent (250 x 250 x 2 mm) under the typical semi -drought climate Adsorption dynamics. The author found that, in addition to the reduction of the adsorption performance of the actual blocking agent relative to the adsorption performance of the milligraphic test sample, there is a significant non -match between the water capture and release rate, and the absorption rate is much higher than the adsorption rate. The maximum quality change of adsorption is only 1/10 of the maximum change of the inhalation process. For this reason, the author designed a portable electric heating air water extraction system for the optimization of heat transfer, and adopted the heat grid to achieve natural convection and radiation shielding to improve the efficiency of relief and condensation.

Common air -taking operation mode (a) day and night single cycle; (b) continuous formula; (C) batch replacement mode proposed

The author does not adopt a common day and night single loop (A) and the continuous formula of adsorption-relievable (B) operation mode, but proposes a unique batch operation strategy (C): Multi-adsorbent agent It is exposed to an environment of high relative humidity to absorb water vapor, and then alternately batch of water to release water to release water to make full use of the highly humidity environment at night, while maintaining a high solution rate throughout the day. In actual equipment operation, this operation strategy requires the portability, adaptability and stability of hygroscopic materials and water removal devices. The adsorption agent used in the article has the characteristics of expanding production, low cost, light quality, and good stability. It is suitable for multiple adsorption agents to make and carry at the same time, which can be quickly deployed into the actual application. Disassembled, reappeared and carried by single. These characteristics make a single -day high -yield water volume of this model.

The air is performed in the semi -arid climate (Lanzhou, Gansu, China). The minimum relative relative humidity during the local experiment was 15%. The water removal of 311.69 g (311.69/Day) was finally realized, with a energy consumption of 0.695 kWh (448.5 ml/kWh), which exceeded the 100 gram of single -day water production. From the perspective of the entire device level, the advanced thermal design of the device, avoiding complex auxiliary equipment (such as fans, condenser), and the full use of the batch processing strategy that uses the suction time to jointly contribute to such a high amount of water extraction. In the end, a portable air with a volume of 5.6 liters and a weight of 3.2 kg achieved a single -day water extraction volume beyond 100 milliliters, showing the obvious advantages of the entire device in terms of weight, space and water extraction. In the six consecutive days of simulation of the cycle stability test of Lanzhou spring and autumn, winter and summer conditions, the air water removal device achieved a stable water extraction.

The continuous work stability and amount of water removal in the air water removal device under different simulation weather conditions

Vegetable Performance Forecast

In order to comprehensively evaluate the potential of water production, the author chose a typical climate area such as global drought, semi -drought and humid climate, and conservatively estimated the water production under each climate. Affected by the relative humidity of the environment, the amount of water removal of more than 1 L/Day can be achieved under the humid climate of Birmingham in the UK, and the daily water output of the dry season in the Sahara desert is only about 150 ml. At the same time, the prediction shows that except for the Qinghai -Tibet Plateau, North Africa and other regions, in most areas, the water production potential of the water removal device exceeds 350 ml/day.

Adsorption air water removal technology is a novel technology that has emerged in low humidity environments in recent years. It has important research significance and application value for obtaining drinking water under arid areas, networking areas and emergency conditions. The work is expected to provide the next generation of air water extraction system from three aspects: material, device design to model innovation.

In recent years, the ITEWA team led by Professor Wang Ruzhu has published more than 30 cross -disciplinary dissertations in Joule, Energy & Environmental Science, Advanced Material, Matter, Nature Communications, Chemical Society Reviews.The cutting-edge basic scientific issues and key technologies in the field aim to implement the overall solutions of the materials-device-device-system level through the interdisciplinary interdisciplinary solution to promote breakthrough progress in related fields.Thesis link: https://www.nature.com/articleS/S41467-022-33062-w

Supply unit: School of Mechanical and Power Engineering

Editor on duty: Wang Ning

Editor in charge: Qi Jie

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