您将学到什么：
- The shortcomings of conventional desalination units.
- 如何使用高级电子和化学制定新方法和测试。
- The performance achieved by this unit in field tests.
显然是没有需要“证明”benefits of portable, on-the-spot water desalination and purification. While many portable desalination systems based on reverse osmosis are already commercially available, they’re not a good fit for remote locations due to their need for power-hungry, high-pressure pumping and continual user maintenance. If only there was a portable, maintenance-free system that could operate from solar power, right?
It looks like we’re getting very close, as a team based at MIT in conjunction with participants from Northeastern University and the U.S. Army Combat Capabilities Development Command (DEVCOM), has devised, built, and field-tested a 10-kg (22 lb.), portable (42 × 33.5 × 19 cm3）淡化单元。它去除颗粒和盐以产生饮用水。该系统使用多阶段的电膜过程，而不是常规的反渗透（图。1）。
The user-friendly design is self-managed—it requires no ongoing user attention since all measurement and control algorithms are embedded in its firmware, and it’s externally controlled by a smartphone. It operates at the push of a single button and automatically generates drinking water that exceeds World Health Organization (WHO) quality standards.
除脱盐外，该系统还将悬浮固体从源水中降低至少10倍，即使从浊度高于30 NTU的源水中产生了清澈的水（<1 NTU）（即，由外浊度高于30 ntu（即，通过浑浊浪潮）。注意：肾小管浊度单元（NTU）是用于测量流体浊度或水中悬浮颗粒的存在的标准参数。
无需过滤
该单元在现场使用方面的简单性的关键是，与其他需要水通过过滤器的便携式淡化单元不同，该设备使用电力从饮用水中去除颗粒。消除对更换过滤器的需求大大减少了长期维护要求。
取而代之的是，它们的单元依赖于一种称为离子浓度极化（ICP）的技术，该技术由MIT组率先超过10年前。（图2）。ICP工艺没有使用众所周知的过滤技术，而是将电场应用于位于水通道上方和下方的膜上。这些膜在过去的过去，包括盐分子，细菌和病毒，呈阳性或负电荷的颗粒。带电的颗粒被漏斗到最终排出的第二流中。
ICP +电透析
该过程可以去除溶解和悬浮固体，从而使清洁的水通过通道。由于它仅需要一个低压泵，因此ICP比其他技术使用的能量少。但是，ICP并不总是清除漂浮在通道中间的所有盐。为了弥补这一缺点，研究人员添加了第二个称为电透析（ED）的过程，以去除剩余的盐离子（图3）。
该团队使用机器学习来找到ICP和电透析模块的最佳组合。最佳设置包括一个两阶段的ICP工艺，第一阶段的水流过六个模块，然后在第二阶段穿过三个模块，然后是单个电透析过程。
系统的电子设备提供过程测量和管理，并使用许多闭环传感器来监视关键流量，浓度和其他关键因素（图4）。
由于应用程序的性质，鉴于应用程序的性质，子组件以及最终产品必须紧凑和坚固。它还需要适应涉及电子设备以及泵，油管和流体控制的“混合信号”设计（图5）。
试验结果
After running experiments in the lab using water with different salinity and turbidity levels, they field-tested the device at Boston’s Carson Beach. In about half an hour, the device had filled a plastic drinking cup with clear, drinkable water.
The resulting water exceeded WHO quality guidelines, and the unit reduced the amount of suspended solids by at least a factor of 10. Their prototype generated drinking water at a rate of 0.3 liters per hour. It requires only 20 watt-hours per liter—an important performance metric.
“This is really the culmination of a 10-year journey that I and my group have been on. We worked for years on the physics behind individual desalination processes, but pushing all those advances into a box, building a system, and demonstrating it in the ocean, that was a really meaningful and rewarding experience for me,” said senior author Jongyoon Han, a professor of electrical engineering and computer science and of biological engineering, and a member of the Research Laboratory of Electronics (RLE).
他补充说：“即使在第一次奔跑中，这也是成功的，这令人兴奋和令人惊讶。但是我认为我们成功的主要原因是我们在此过程中取得的所有这些小进步的积累。”
Their work，，，，including an explanation and detailedanalysis of the underlying chemistry，，，，is presented in their paper “Portable Seawater Desalination System for Generating Drinkable Water in Remote Locations“ 出版于Environmental Science & Technology（美国化学学会杂志）得到了全面的支持Supporting Information文件。还可以观看这个两分钟的视频，该视频提供了动手概述：
