Water makes up over 70% of the earth’s surface but the vast majority of it is in a state unusable for human use. However, through advanced treatment systems now available we can access water of most kinds and turn it into water for everyday use, even for drinking.
There are different types of usable water. For example, drinking water has different characteristics from water used in cooling systems. Regulatory systems are in place at both national and international level to ensure that water used meets certain standards. The World Health Organization (WHO) publishes global guidelines for drinking water standards and the International Organization for Standardization (ISO) regulates water for industrial use.
Drinking Water for Human Consumption
Water is essential for human life. Around 60% of an adult human body is water and we need to consume it to remain healthy. Drinking water is provided in many countries by a piped water supply drawn from freshwater sources (groundwater via pumps and wells, or surface water via lakes, rivers, etc.), with bottled water also available for sale.
However, this water isn’t ready to drink at the point of extraction and needs to undergo a treatment process before it is provided for consumption. Contaminants can include micro-organisms such as bacteria, chemicals (e.g. nitrate and pesticides) and traces of metal (e.g. lead and copper).
Many developing countries still don’t have the technology to extract and treat water to provide a regular drinking supply. According to the WHO, around a third of the global population still don’t have access to a safe drinking water supply. Among countries that do have the purification technology to provide safe drinking water, quality can vary greatly both between and even within nations. Quality depends on how good the treatment processes and equipments are as well as how well maintained the water infrastructure (e.g. piping network) is.
The process of purifying the water to make it drinkable varies depending on its source but typically includes:
- Pre-filtration usually using either sand or drum filters.
- Addition of chemicals such as calcium oxide and sodium hydroxide.
- Disinfection using ozone to kill any micro-organisms present.
- Carbon filtration to remove any existing micro-pollutants and also to improve taste.
- Preservation techniques such as chlorination.
Water for Other Household and Industrial Uses
Different types of water are used for household and industrial purposes, and this water is produced using different techniques and has different qualities. Drinking water contains minerals such as calcium and magnesium which make it more healthy and nutritious. However, this affects its cleansing qualities and can cause problems such as the formation of hard deposits inside domestic boilers or industrial equipment.
For this reason, water is put through different treatment processes involving purification to make it more suitable for alternative uses. Two of the main types of this water are;
Demineralized Water – Known as ‘demi water’, this is water that has the majority of its minerals and salts removed (calcium, chloride, sulphate, magnesium, sodium, etc.) to make it more suitable for a range of industrial purposes. Demi water can be produced using a number of different processes including reverse osmosis, capacitive deionization, carbon filtering, microfiltration and ultraviolet oxidation. You can also demineralize water through distillation, although distilled water and demi water are not exactly the same.
Demi water is used in a range of equipment including biolers, coolers, various industrial and electronics applications, carwash systems, cosmetics, lead-acid batteries and household irons.
Ultrapure Water – This is water that has been purified to the highest standards. Typically this water will contain only H2O, H+ and OH- ions in equilibrium. Whereas demi water is purified of its mineral content, ultrapure water has been cleansed of all organic, semiorganic and biological components including all bacterial organisms. In addition to being ultrapure, this water has very low conductivity and is thus suitable for most applications in the semiconductor industry. It’s also commonly used in the microchip, pharmaceutical and biotechnology industries.
Ultrapure water is usually turned into demi water first, then further purification and polishing processes will be performed (e.g. electrodeionization or ultrafiltration) until the water reaches the required standard.
Neither demi water nor ultrapure water is dangerous to drink, however as it has been ‘cleansed’ of all minerals and good bacteria it has no nutritional or health benefits.
Drinking water, demi water and ultrapure water can be produced from all types of source water using the latest in water technology. Water Experts can advise you on installing on-site equipment at your business or home to produce sustainable water supplies of all qualities to suit your needs. Our SolarAQ systems are solar-powered but can also be connected to any renewal energy source.