FreeWord – Everything you need to know about water treatment
Have a gulp of water and enjoy, it’s FreeWord time!
For some of us, the simple turn of a tap delivers clean, drinkable water which can easily be taken for granted. It’s easy to forget that behind the convenience are water treatment processes, which secure the quality of the potable water and enrich the taste. Moreover, it ensures a sufficient supply of water to meet the community’s needs.
Water is arguably one of the most important natural resources on the planet and a necessity for life. Finding and maintaining a clean water supply has been a constant process throughout human history, and the earliest records of treating water have been found in ancient Greek and Sanskrit writings from 2000 BC.
The Importance of Water Treatment
As a consequence of the increasing population, the demand for drinkable water has been on a constant rise. This has led to serious concerns as the high quality of water supply has been very limited due to the contamination of water with municipal, agricultural, and industrial waste that has led to decreasing water quality. Therefore, the public has become more aware of the importance of water quality control and its effects on our ecosystem.
Water Quality Standards & Legislation
Water-quality standards are presented to help in the selection of suitable water-treatment technologies. The relevant issues such as topical and spatial variations, problems of supply and distribution of safe and pure water, and possible approaches to water management have to be taken into consideration. Especially water-scarce areas should ensure high-quality water treatment processes so the treated water can be reused or recycled, and never wasted.
If you look at the map above, you will notice that there are only a few countries which can guarantee safe drinkable water for all of its citizens.
We are witnessing declining freshwater supplies around the world. Wastewater, which is basically used water, is believed to be the solution to resolve this global crisis. Adequately treated wastewater is a source for many purposes such as irrigation, landscaping, industry, etc. and is a convenient way to conserve our freshwater resources. A proper wastewater treatment allows the maximum amount of water to be reused instead of going to waste. Untreated, the chemical compounds and pathogens in wastewater are destructive for the whole ecosystem. In addition, the treated water is usually added to groundwater or surface water for further cleansing before being sent to a potable water supply where it is re-treated.
Water Treatment Processes
There are two main types of water treatment plants: potable water plant and wastewater plant. Both serve the purpose of removing contaminants from the water, but in general, the output of wastewater plants are streams or rivers, and the output of potable water plants is your city’s pipe network distribution system. So, how exactly does a treatment plant take dirty river water and turn it into clean water? Well, through processes involving chemicals and filters, water can be removed off most toxins and hazards and become potable again.
The source of water and its initial condition prior to being treated usually determines the water treatment process. Wastewater from non-residential sources generally requires additional treatment steps. A variety of procedures are used to remove these impurities, including chemical, biological, and physical processes.
Pre-treatment – During this stage, easily removable materials such as sand, gravel, oils, greases, and large items are removed.
Primary treatment – Wastewater is transported through primary purifiers, which are large tanks where the sludge settles to the bottom and greases and oils rise to the top. During this process, solids and liquids separate as solids settle on the bottom of the tanks. Later they can be assembled and moved and handled separately.
Secondary treatment – Aerobic biological processes: protozoa and bacteria that eat biodegradable soluble organic pollutants are used to break down the biological content of wastewater (including human or food waste and soaps).
Tertiary treatment – The wastewater is raised through disinfection practices mostly as chlorination or the use of ultraviolet light. There are other methods like sand filtration, but they are rarely used. Chlorine is inexpensive and effective but can create carcinogenic compounds. Ultraviolet light results in water that’s healthier for the environment, since it’s deadly to bacteria and viruses by changing their genetic structure, which makes them incapable of reproducing. Moreover, a combination of tertiary treatments can be used.
Aerobic digestion – It is a natural oxidation process that causes an efficient breakdown of organic pollutants and yields. Aerobic wastewater treatment is a rapid and efficient process that removes at least 98 percent of organic contaminants. On the negative side, Aerobic digestion consumes large amounts of energy, resulting in large amounts of bio-solids, or sludge, which require disposal.
Anaerobic digestion – Anaerobic microbes are bacteria and microorganisms that function in the absence of oxygen. Anaerobic wastewater treatment is more environmentally friendly than aerobic digestion, because it produces less biomass, requires less energy, and produces methane that can be recycled. On the negatives, it’s slow and less efficient than aerobic digestion (70 to 95% of contaminants can be removed).
For more detailed information and a better understanding of wastewater treatment, check out the following video.
Water pollution has become a challenging problem all over the globe, causing a shortage of useful water, and therefore a pressing demand for a new wastewater treatment technology. As a result, a promising green chemical approach to wastewater treatment advanced oxidation processes (AOPs) have been developed. AOPs are believed to be finding a dominant position among various wastewater treatment technologies in the years to come.
The importance of water purification will only become more dominant year by year in our society, as consumption keeps increasing. Filters and new technologies should be continuously integrated into the process to fulfill community needs while ensuring pathogens from causing outbreaks. Perhaps with the help of implementing blockchain technology for water quantity and quality data monitoring, we can achieve this ultimate goal to guarantee the necessary amount of water for every inhabitant of this planet. Cheers!
Image source: https://www.wsp.org/content/2016-cartoon-calendar