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Water, water everywhere, but . . .

Water is a common chemical substance that is essential for the survival of all known forms of life. In typical usage, water refers only to its liquid form or state, but the substance also has a solid state, ice, and a gaseous state, water vapor. About 1,460 teratonnes (Tt) of water covers 71% of the Earth's surface, mostly in oceans and other large water bodies, with 1.6% of water below ground in aquifers and 0.001% in the air as vapor, clouds (formed of solid and liquid water particles suspended in air), and precipitation. Some of the Earth's water is contained within man-made and natural objects near the Earth's surface such as water towers, animal and plant bodies, manufactured products, and food stores.

Saltwater oceans hold 97% of surface water, glaciers and polar ice caps 2.4%, and other land surface water such as rivers, lakes and ponds 0.6%. Water moves continually through a cycle of evaporation or transpiration (evapotranspiration), precipitation, and runoff, usually reaching the sea. Winds carry water vapor over land at the same rate as runoff into the sea, about 36 Tt per year. Over land, evaporation and transpiration contribute another 71 Tt per year to the precipitation of 107 Tt per year over land. Some water is trapped for varying periods in ice caps, glaciers, aquifers, or in lakes, sometimes providing fresh water for life on land. Clean, fresh water is essential to human and other life. However, in many parts of the world - especially developing countries - it is in short supply. Water is a solvent for a wide variety of chemical substances.

Though the total amount of water on this planet has never changed, the nature of that water is changing. Everything from where rain falls to the chemical makeup of the oceans is in flux. And these changes are forcing us to ask some very difficult questions about how and where we live and do business.

Water Quality

No natural water is actually pure since it contains a variety of materials, either dissolved or in suspension, as well as micro-organisms (many of these are harmless to humans, plants and animals).

However, it is normally difficult to determine visually whether a water sample is safe to drink or that is suitable for irrigation. During drought conditions it becomes acceptable to use water of lower quality, particularly for non-essential applications. In those circumstances it is even more important to regularly check the water quality since contaminanation frequently increases during long dry periods.

Water Treatment

Water treatment describes a process used to make water more acceptable for a desired end-use. These can include use as drinking water, industrial processes, medical and many other uses. The goal of all water treatment process is to remove existing contaminants in the water, improving it for subsequent use.

The goal may be to allow treated water to discharge into the natural environment without adverse ecological impact. These processes may be physical such as settling, chemical such as disinfection or coagulation, or biological such as lagooning, slow sand filtration or activated sludge.

Industrial Water Treatment can be classified into the following categories:

  • Boiler water treatment
  • Cooling water treatment
  • Wastewater treatment

Water treatment is used to optimize most water-based industrial processes, such as: heating, cooling, processing, cleaning, and rinsing, so that operating costs and risks are reduced. Poor water treatment lets water interact with the surfaces of pipes and vessels which contain it. Steam boilers can scale up or corrode, and these deposits will mean more fuel is needed to heat the same amount of water. Cooling towers can also scale up and corrode, but left untreated, the warm, dirty water they can contain will encourage bacteria to grow, and Legionnaires' Disease can be the fatal consequence. Domestic water can become unsafe to drink if proper hygiene measures are neglected.

In many cases, effluent water from one process might be perfectly suitable for reuse in another process somewhere else on site. With the proper treatment, a significant proportion of industrial on-site wastewater might be reusable. This can save money in three ways: lower charges for lower water consumption, lower charges for the smaller volume of effluent water discharged and lower energy costs due to the recovery of heat in recycled wastewater.

You cannot manage what you dont or cannot measure. Water is poorly understood and many times widely mismanaged. More data is needed to fully understand how water is used by industry, agriculture, and individuals. Water use must be monitored and metered to locate inefficiencies. And both the data and the analyses that result should be shared between central governments, local authorities, academics, and industry.

We provide a range of hand held and on-line process-monitoring instruments that have been cost effectively designed for measuring and controlling the main parameters in the water and offer advanced features.