Environmental Hydrotech, Inc.

      3 Hixson Road Croton-on-Hudson, NY  10520

                       Tel : (914) 271-0175   Fax: (914) 271-0174


   Water Purification Experts -  Manufacturer of Reverse Osmosis Systems -  Supplier of All Types of  Water Filters 

Home Up Water Purification Recycling Wastewater



Reverse Osmosis (RO) is the process that removes dissolved organics and salts by flowing the feed stream under pressure across a semi permeable membrane. 

Pressurized feed water flows across a membrane, with a portion of the feed permeating the membrane.  The balance of the feed sweeps parallel to the surface of the membrane to exit the system without being filtered.  The filtered stream is the "permeate" because it has permeated the membrane.  The second stream is the "concentrate" because it carries off the concentrated contaminants rejected by the membrane.  Since the concentrate flows parallel to the membrane instead of perpendicular, the process is called "cross flow filtration".

When used upstream of deionization beds (DI), regeneration cycles are extended by a factor of 10-20 times.  This results in considerable cost savings and reduction of chemical discharge to the environment.    


The above reverse osmosis system includes dual carbon beds for dechlorinating city water, micro filtration for removal of fine particulate, a reverse osmosis system to remove dissolved solids and a repressurization system to deliver water under pressure to downstream locations.