Water Treatment Chemicals

This page is intended to provide you with a description of some common water
treatment chemicals, along with links to commercial suppliers.

Algicide

An algicide is a chemical which when added to water kills algae and
blue-green algae. Some examples of common algicides include copper sulphate,
chelated copper-based products, benzalkonium chloride and simazine. Whilst
effective in reduction of algae the use of algicides to control algal blooms
is not recommended for environmental reasons and the chemical should only be
used in emergancy cases. Like all chemicals this should not be considered a
long term solution to algal problems.

All copper-based algicides will damage and in most cases kill algal cells.
This reaction leads to the release of algal toxins in to the water, these
toxins can pass more easily through the water treatment filters than the
intact algal cells. If algicides are used in potable water supply reservoirs
the water should not be used until the toxins and odours degrade which could
take several months.

It is a lot more difficult to detect algal toxins than whole algal cells. So
once algal cells are killed, the only way to determine whether algal toxins
are still present in the water is through toxin testing. The toxins produced
by blue-green algae are generally very stable compounds that are resistant
to chemical breakdown and may remain in natural waters for several months.

Some risks associated with using copper-based algicides include:

• The accumulation of copper in the sediments;
• The growth of species of blue-green algae that are resistant to the algicide may cause greater water quality problems;
• The mass release of toxins from the algal cells;

Chlorine

Chlorine is, essentially, bleach although it is not said to be harmful in
small quantities it has been linked to cancer as a known carcinogen
(cancer-causing agents) when combined with naturally occuring acids.
Chlorine is such a big subject area I can’t hope to cover it all hear but
you can find more information on how to use Chlorine and may other
delightful facts on the Chlorine Online site.

Chlorine Dioxide

Chlorine Dioxide water treatment through the use of a dosing system can have instant high yield results in water purification because of its unique selective properties. To find out more about chlorine dioxide’s use for Water Treatment visit Feedwater.

Clarifiers

Primary Clarifiers help slow the speed of the wastewater to allow the solids
to settle out side of the wastewater. A secondary clarifier can be used to
settle out microorganisms from the activated sludge process.

Clarifiers typically have rotating arms, which help to remove scum from the
surface of the water. The sludge or biosolids are usually collected at the
bottom of the clarifier and then sent to a digester for further treatment.

For further information you can see the following pages:

Information about a inclined plate clarifier
Information about parallel plate clarifier
Information on circular mechanical clarifier

Filter Cleanser

Is an acid-based granular formulation that cleans and unclogs sand and cartridge filters of grease, oils and sludge.

You can buy it at the following sites:

Swimthings.com
Kusuri.co.uk

Dry or Muriatic Acid

Dry or muriatic acid can be used to decrease the pH of your water and should
be used according to the manufacturars instructions otherwise you could end
up with water at a danerously acidic pH level.

Soda Ash or Sodium bicarbonate

Soda ash or sodium bicarbonate can be used to increase the pH of your water
and should be used according to the manufacturars instructions otherwise you
could end up with water at a danerously high pH level.