Experimental Study on the Resistance and Splash Performances of Water Collecting Devices for Mechanical Draft Cooling Towers

In recent years,water collecting systems,with the associated advantages of energy saving and noise reduction,have become the foundation for the development of a scheme to optimize the structure of cooling towers.To explore the feasibility of this approach for mechanical draft cooling towers,a small-scale experimental device has been built to study the resistance and splash performances of three U-type water collecting devices(WCDs)for different water flow rates and wind speeds.The experimental results show that within the considered ranges of wind speed and water flow rate,the pressure drop of the different WCDs can vary significantly.The resistance and local splash performances can also be remarkably different.Some recommendations about the most suitable system are provided.Moreover,a regression analysis of the experimental data is conducted,and the resulting fitting formulas for resistance and splash performance of WCD are reported.

Study on micro-water-collecting technique in dryland field of spring maize

This paper analyses the effect of water storage and soil moisture conservation by means of micro water collecting technique in the dryland field of spring maize. The results indicate that the rainfall infiltration depth is deeper by means of micro water collecting treatment than that of the control. In micro water collecting treatment, the amount of soil water storage within 0～200 cm of soil layers increases by 50.5 mm, 13.5～58.6 mm, and 24.5 mm respectively during seedling stage, the critical stage of water requirement and the ripening and harvesting stage compared with the control. The micro water collecting technique not only has the function of regulating and adjusting the amount and distribution of field evapotranspiration, but also can raise the water use efficiency, which results in an obvious effect of increasing crop yield, especially in the dry years.

Spider-capture-silk mimicking fibers with high-performance fog collection derived from superhydrophilicity and volume-swelling of gelatin knots

Spider-capture-silk(SCS)can directionally capture and transport water from humid air relying on the unique geometrical structure.Although there have been adequate reports on the fabrication of artificial SCSs from petroleum-based materials,it remains a big challenge to innovate bio-based SCS mimicking fibers with high-performance fog collection ability and efficiency simultaneously.Herein,we report an eco-friendly and economical fiber system for water collection by coating gelatin on degummed silk.Compared to the previously reported fibers with the best fog collection ability(~13.10μL),Gelatin on silk fiber 10(GSF10)can collect larger water droplet(~16.70μL in 330 s)with~98%less mass.Meanwhile,the water collection efficiency of GSF10 demonstrates~72%and~48%enhancement to the existing best water collection polymer coated SCS fibers and spidroin eMaSp2 coated degummed silk respectively in terms of volume-to-TCL(vapor-liquid-solid three-phase contact line)index.The simultaneous function of superhydro-philicity,surface energy gradient,and~65%water-induced volume swelling of the gelatin knots are the key factors in advancing the water collection performance.Abundant availability of feedstocks and~75%improved space utiliza-tion guarantee the scalability and practical application of such bio-based fiber.

An unusual superhydrophilic/superoleophobic sponge for oil-water separation

Development of porous materials with anti-fouling and remote controllability is highly desired for oil-water separation application yet still challenging. Herein, to address this challenge, a sponge with unusual superhydrophilicity/superoleophobicity and magnetic property was fabricated through a dip-coating process. To exploit its superhydrophilic/superoleophobic property, the obtained sponge was used as a reusable water sorbent scaffold to collect water from bulk oils without absorbing any oil. Owing to its magnetic property, the sponge was manipulated remotely by a magnet without touching it directly during the whole water collection process, which could potentially lower the cost of the water collection process. Apart from acting as a water-absorbing material, the sponge can also be used as affiliation material to separate water from oil-water mixture and oil in water emulsion selectively, when fixed into a cone funnel. This research provides a key addition to the field of oil-water separation materials.