Tag Archives: reverse osmosis



Not all new ideas become commercial products! (http://dr-monsrs.net)
Not all new ideas become commercial products!   (http://dr-monsrs.net)


Anyone can come up with an idea for a useful new device, but it always is uncertain whether that can be converted into a new product for sale. Typically, there is a long chain of interactions between the original idea for a new device and the marketed new product!  This chain of events is quite general, and is good for everything from a new refining process that generates cheaper gasoline, to new expensive diagnostic kits for identifying specific diseases.  This article will outline the general sequence whereby scientific research, engineering development, and industrial modifications lead to new commercial products, using the important example of producing drinkable water from seawater.

Background on desalination [1,2]! 

All humans get thirsty every day!  Water to be drinkable (i.e., potable water) must be freed from bacteria, dissolved salts, sediments, and various chemicals.  Ocean water is much more plentiful than natural fresh water, but cannot be used directly to quench thirst.  Desalination (i.e., removal of salts from the starting liquid) has primary importance for purifying water, and is increasingly important as the global human population increases and the amount of natural fresh water decreases.

Removing dissolved salts can be accomplished by several different ways.  Most people are familiar with water purification by distillation (i.e., boiling water to produce steam, followed by cooling to condense the steam into salt-free liquid water).  Where large numbers of people need to have potable water for drinking, simple distillation is not usable because it has insufficient speed and capacity, as well as a high energy cost.

In practice, physical filtration of salty source water is used commonly for pre-treatment to remove sediments and microorganisms.  The processes utilized to separate filtered water from dissolved salts involve chemical or physical mechanisms working at the level of molecules and ions (e.g., adhesion, ion exchanges, permeation through very small pores, precipitation, etc.).  One of the processes frequently being utilized is reverse osmosis (i.e., pressure forces water molecules through minute pores that are too small to allow passage of hydrated salt ions).  In countries having little natural fresh water, desalination of ocean water often is conducted by special facilities inside large buildings that use reverse osmosis to produce many thousands of gallons of purified water every day.

Involvement of research and engineering [1,2]! 

Commercial devices for desalination now are available for individual people, and very large-scale plants are providing potable water for substantial populations.  Success of desalination is evaluated with regard to costs for energy and operation, efficiency, environmental effects, final purity, rate of purification, stability, suitability for human consumption (e.g., deficient iodine content), etc.  Research and development  into all these aspects is ongoing, and involves everything from materials science (e.g., new or modified membranes with pores having better selectivity) to systems engineering (e.g., using heat generated from nuclear reactors to facilitate desalination processes). Many investigations into desalination already have been conducted; the science journal, Desalination, is now approaching publication of its 400th volume!  As availability of natural fresh water in our world diminishes, the importance of making yet further improvements in desalination continues to rise.

Basic research by scientists seeks to answer questions without regard to later practical uses.  For desalination, basic research has established the physics and chemistry of the different mechanisms involved (e.g., detailed characteristics, purity and residual salt content, ion selectivity of pores, capacity, energy required, etc.).  Applied research then examines the fundamentals of desalination with regard to using modifications and different kinds of materials and processes to give better results.

Development of desalination products and processes seeks to modify and combine the results of applied research so the activities of each part of desalination are optimized for commercial production or industrial usage.  The goal is to obtain the largest volume and best purity with the least  cost in the shortest time.  This area of work is done by engineers, and commonly takes place in industrial research centers.  Testing of prototypes often necessitates further changes in design.  Scaling is evaluated for applications with different volume requirements for pure water output from various salty sources.  Finally, industrialists work to offer commercially viable new or improved versions of desalination both in small personal devices and in large plants for public installations.

General discussion! 

The long sequence of work needed for any new commercial product or process (e.g., better and cheaper batteries, shoelaces that last longer, safe new pharmaceutical medicines, self-driving automobiles, etc.) is general and much the same as was just described for the example of desalination!  The entire sequence requires the efforts by many different people working as individuals, teams, and companies.  All of this research and development leads to new products or processes playing a very important role for making our lives better!

Concluding remarks! 

A common sequence of input from computer specialists, inventors, research scientists, engineers, technical workers, and industrial developers is needed to enable new commercial products and new industrial developments to be offered to the public.  Although one individual can have key importance, completing the entire sequence requires input from many people!


[1]  Fritzmann, C., Löwenberg, J., Wintgens, T., and Melin, T., 2007.  State-of-the-art of reverse osmosis desalinationDesalination  216:1-76.  Available on the internet at:  http://www.sciencedirect.com/science/article/pii/S0011916407004250 .

[2]  Thiel, G.P., June 2015.  Salty solutionsPhysics Today  VOL:66-67.  Available on the internet at:  http://scitation.aip.org/content/aip/magazine/physicstoday/article/68/6/10.1063/PT.3.2828 .