Mart Cyclone 30 Series, Installation, Operation And Maintenance Manual, Page: 206 / 322

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Standard Turntable Power Washer v.
4
.0 The MART Corporation
Chemical Management
When a washer is first put into service, it is easy to compute the concentration of the
cleaning compound, because you started with a fixed volume of water and added a
known quantity of chemical. After you begin using the washer, however, you can only
estimate the chemical concentration -- until you drain the washer, clean it out, and
recharge it with fresh water and chemical.
There are two commonly used estimating tools:
·
Conductivity measuring systems
·
Titration kits
Conductivity Measurement
A conductivity measuring system measures the strength of a fixed electrical current
flowing between two or more electrodes that are held at a fixed distance. Since the
addition of cleaning compounds (chemical) to water changes the capacity of water to
conduct electricity, conductivity measuring systems can provide an
estimate of the
strength of the chemical in the solution by measuring the relative conductivity of the
solution.
Unfortunately, compounds other than cleaning chemicals also affect the conductivity of
the solution in the washer. These compounds include iron oxide (rust) and carbon, both
commonly found in most washing applications.
This means that while conductivity measuring systems can be used as a control point,
this is done with the understanding that the oils, greases, metal particles and other
contaminants that are byproducts of the cleaning process affect conductivity.
Thus, the only true measure of chemical concentration is to use titration tests in
conjunction with conductivity measurements to determine a correlation. Once you know
the correlation, you can get a fairly accurate estimate of chemical concentration in the
solution by using a conductivity measuring system.
Titration
Titration is the estimation of the strength of a compound by measuring the amount of
another compound of known strength that is required to produce an observable reaction.
Almost all titration kits supplied with cleaning compounds use phenolphthalein (indicator
P) as a reactant, and an acid (hydrochloric or phosphoric) as a neutralizer. The
indicator P turns red or pink or blue when added to a sample of the solution. By
counting the drops of acid it takes to turn the solution back to its original color, you can
arrive at a good
estimate of the chemical concentration.