A  venturi with an opening at the throat used to educt (suck in) air or  liquid. The common method of introducing brine into a water softener.

The  effectiveness of the operational performance of an ion exchanger.  Efficiency in the adsorption of ions is expressed as the quantity of  regenerant required to effect the removal of a specified unit weight of  adsorbed material, e.g., pounds of acid per kilogram of salt removed.

The  outflow of a water treatment device. Sometimes used to mean the product  water of a given water conditioning device or system.

A dialysis process using semi-permeable membranes.

A  chemical compound which dissociates or ionizes in water to produce a  solution which will conduct an electric current. Could be an acid, base,  or salt.

The  stripping of adsorbed ions from an ion exchange material by the use of  solutions containing other ions in concentrations higher than those of  the ions to be stripped. The process of washing out adsorbed material,  especially by use of a solvent.

The  end point is that point in the exhaustion run of a water conditioner  such as a softener or deionizer at which the water quality has dropped  below an acceptable level

The  aging process of a body of water caused by the depletion of available  oxygen. It can be accelerated by human activities that add too many  nutrients to the water such as barn yard runoff or fertilizers.

Locations  on ion exchange resin beads which hold mobile ions that are available  for exchange with other ions in a solution passing through the bed.  These sites are also called functional groups.

The rate with which one ion is displaced from an exchanger in favor of another.

The  state of the adsorbent such as activated carbon, a water softener, or a  deionizer that is no longer capable of the removal of a specific  pollutant or of useful ion exchange. The exhaustion point is determined  arbitrarily in terms of: (a) the presence or increase of an adsorbent  contaminant as chlorine; (b) a value in parts per million of ions in the  effluent solution; (c) the reduction in quality of the effluent water  determined by a conductivity bridge which measures the resistance of the  water to the flow of an electric current.