Reported to account for approximately seventy-one percent of the earth’s surface, water can be found in the air (as water vapor), animals and aquifers, in the ground (as soil moisture), in glaciers and icecaps, in lakes and rivers, and plants (Freshwater Crisis, 2019). However, despite its seemingly ubiquitous nature, only approximately 2.5 percent of this water is considered pure and potable causing the ever-rising global water crisis (Freshwater Crisis, 2019). The need to purify water, as a result, is not only indispensable but also will contribute to long-term environmental sustainability.
The aspiration and hope for a better, cleaner and healthier environment have been at the forefront of man’s mind for quite a while now. This goal became prominent enough for the United Nations to include maintaining environmental sustainability among its Millennium Development Goals (MDGs) in 2000 (UN MDGs, n.d.). One of the objectives of the seventh Millennium Development Goal is to significantly decrease the population of individuals without access to safe drinking water, a target which was attained as many as five years before the schedule (UN MDGs, n.d.). Despite the attainment of this goal, there are still many more people who are without pure water. As a result, more it is expedient that more effort is made to purify more water.
A History of Wanting Pure Drinking Water for the Health of the Human Race
Dating as far back as 2000 BC, water purification involves eliminating undesired biological, chemical, inorganic, and organic contaminants from water.
Several methods have been put forward to attain this goal of water purification for a cleaner and safer world. Several years back, water purification was limited to boiling water as well as using alum, gravel and sand filtrations, and straining techniques. Then, the primary aim of purifying water was to improve on its odor and taste, especially since the research on biological (microorganisms) and chemical contaminants were limited until the mid-19th century after the first cholera epidemic.
After this outbreak, more comprehensive research was done to investigate alternative factors besides the smell and taste of water that could influence the quality of the water. The result of this research included the implementation of chlorine to purify water and the management of public water safety through the installation of municipal water filters.
What Affects the Quality of the Earth’s Drinking Water?
Designed to solve the existing challenges, the various techniques, past, present, and future, attempts to address the principal factors affecting the purity of water, some of which include:
- Coastal degradation and the demanding conditions influencing the rebuilding of vintage infrastructure. Elements contributing to water purification and coastal-device degradation encompass land use, power systems, urban sprawl, and weather exchange.
- Pollution and nutrient effects related to agricultural runoffs of soils and vitamins. The most prominent factors contributing to pollution and nutrient effects include land use, technologic changes, and weather alterations.
- Increasing portions of waste with a much broader array of substances results from population increase, power utilization, technologic change, and changing consumption.
Although alternative methods have been put forward and used to purify water, thus far four principal techniques have been at the forefront.
Time-Tested, Principal Water Treatment Methods
In addition to being the easiest and most accessible water purification technique, boiling is also the cheapest method of purification and involves boiling clean water to the boiling point (4 Methods to Purify Your Water, 2018).
Although cheap, Chlorine is an effective and powerful chemical that kills germs, parasites and other disease-causing organisms in ground and tap water, and may exist as tablets or liquid (4 Methods to Purify Your Water, 2018). Despite its efficacy, however, there are ever-increasing concerns about the byproducts of Chlorine. Studies have demonstrated that often, the chlorination of water produces Trihalomethanes (THMs) a product of the reaction between chlorine and the organic components of water (Hood, 2005). Now associated with the prevalence of adverse health effects like cancer and negative reproductive outcomes, the two most common forms of THMs are chloroform (reportedly poisonous to the respiratory system upon inhalation) and bromodichloromethane (Caballero, 2003; Hood, 2005). Further research reported that in addition to exposure to THMs via oral route, the risk of disease increased in individuals exposed to “dermal absorption and inhalation of THMs associated with everyday tap water use” (Hood, 2005, para. 1) which can result in relatively higher blood-THM concentrations than simply drinking the water will cause (Hood, 2005).
Although this approach is relatively more expensive, it is ideal for cases involving raw, untreated water and uses heat to collect pure water as vapor. Most appropriate for small quantities of water, distillation serves in eliminating bacteria, germs, heavy metals, and salts (4 Methods to Purify Your Water, 2018).
Effective for the selective elimination of smaller molecular compounds, filtration is a relatively less expensive technique of water purification using both chemical and physical processes without depleting the mineral salt content. As a result, filtered water is considered healthier than water subjected to alternative purification methods (4 Methods to Purify Your Water, 2018).
Advance Water Filtration Methods
Over time, however, and with the advancement of technology, the techniques of water purification have and are still in the process of advancing considerably. In a bid to increase productivity, scientists have come up with futuristic and groundbreaking that can simultaneously increase the productivity and availability of pure water and sustain a better and cleaner environment. Some of these ideas include:
This is an innovative method in the improvement of water filtration that converts cow manure into filtered water that can equally be used as fertilizer. This method of water purification utilizes an anaerobic digester to provide electricity from the waste (Gilpin, 2019; Shannon et al., 2010). Coupled with ultrafiltration, reverse osmosis system, this process yields water as its byproduct. It is estimated that the amount of water purified approximates to about half the volume of manure processed (Gilpin, 2019; Shannon et al., 2010).
Improving toilet design
This technique comprises a toilet with a solar panel that energizes an electrochemical reaction to decompose human waste into fertilizer and fuel cells stored in the reactor for cloudy days (Gilpin, 2019). Designed to promote sustainability, the toilet is estimated to last two decades and costs approximately 11 cents daily for maintenance. Promoted by the Gates Foundation, The toilet has the potential to influence the lives of millions (Gilpin, 2019).
As a result of the extensive properties of nanomaterials (massive floor areas, selective permeability, high reactivity, an affinity for particular contaminants, accurate reusability and extraordinary flux fees), nanotechnology is ideal for water purification (Gilpin, 2019; Shannon et al., 2010). Designed to be too large to be filtered through the chemical filter, nanoparticles function by attracting heavy metals and insecticides to remove from the water. Although it is a new procedure for water purification, scientists have recently invented a cheaper nanoparticle water-filtration system that eliminates chemical additives and heavy metals from water, thanks to a multi-layered purifier that blocks contaminants (Gilpin, 2019; Shannon et al., 2010).
Powered by an electricity-generating combination of hydrogen and oxygen cells, hydrogen-powered cars function in water purification through their emission of water vapor (Gilpin, 2019).
This technique utilizes sunlight to purify water and dates back several millennia. Dependent on temperatures and weather conditions, this technique is often expedited by using black carbon-dipped paper. It is estimated that approximately ten to twenty liters of pure water can be acquired through this process, making it a low cost, low energy, but very efficient technique.
This is yet another advanced step in the technology of water purification and involves filtering saltwater from the ocean into drinkable water using a graphene oxide sieve. Another alternative is the use of ultrasound waves to desalinate and purify ocean water and functions in that it uses ultrasound waves to ‘explode’ the unclean ocean water into particles smaller than ten microns. These microns then evaporate and condense, resulting in clean and natural water (Das et al., 2014; Elimelech & Phillip, 2011). Over time and with the advancement of technology, Carbon nanotube (CNT) membranes have improved water purification by significantly reducing the power required to run desalination (Das et al., 2014; Elimelech & Phillip, 2011).
Several advances have been made to improve the availability of pure water on a global scale (Gates, 2015). While some of these advances have been made on the front of creative inventions and technology, several others pertain to policymaking. Through sustainable governance, many big investors like the Bill & Melinda Gates Foundation have invested in research programs like “Omni Processors” (Gates, 2015). Describing any of the various styles of technology that chemically treats fecal sludge to eliminate pathogens and purify water while simultaneously generating income, Omni Processors (OPs) have been demonstrated to be beneficial efficient in the management of freshwater ecosystems and sanitation centers especially in developing international locations like Asia and Sub-Saharan Africa (Gates, 2015).
Summarily, there exists an intricate association between attaining and sustaining a cleaner world and the more objective and seemingly-minute processes like water purification. As technology evolves, so will the water purification process, with future technologies combining both home water filters and municipal water treatment plants. Alternative water purification processes will strive to sustain a cleaner and healthy environment while simultaneously providing purified water.
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- Caballero, B. (2003). Encyclopedia of Food Sciences and Nutrition. Editor.
- Das, R., Ali, M. E., Hamid, S. B. A., Ramakrishna, S., & Chowdhury, Z. Z. (2014). Carbon nanotube membranes for water purification: a bright future in water desalination. Desalination, 336, 97-109. Retrieved from: https://www.sciencedirect.com/science/article/pii/S0011916413006127
- Elimelech, M., & Phillip, W. A. (2011). The future of seawater desalination: energy, technology, and the environment. science, 333(6043), 712-717. Retrieved from: https://sci-hub.tw/10.1126/science.1200488
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- Gilpin, L. (2019). 10 ways technology is changing the future of water. Retrieved from: https://www.techrepublic.com/article/10-ways-technology-is-changing-the-future-of-water/.
- Hood, E. (2005). Tap water and trihalomethanes: flow of concerns continues. Retrieved from: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1257669/
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- United Nations Millennium Development Goals (UN MDGs). (n.d.). Retrieved from https://www.un.org/millenniumgoals/environ.shtml.