By Suhani Awadhiya
Written on: Aug 14, 2023
Last Updated: Aug 15, 2023
Water, a fundamental human right, is necessary for life. Yet, as our planet navigates the challenges of a rapidly changing climate and burgeoning population, its scarcity has affected more than 40 % of the world’s population according to the UN. For millions around the world, the simple act of turning on a tap and being greeted by a steady flow of fresh water is a luxury that remains out of reach. As the sun rises over arid landscapes and coastal shores, it brings with it the promise of a solution that can transform lives: desalination, a method for combating water scarcity!
A scarcity of clean and safe water resources to meet the needs of human populations and ecosystems is categorized as a water deficit. Water contamination, over-extraction, and insufficient infrastructure all contribute to this scarcity. These challenges are compounded in disadvantaged communities due to limited access to technology and financial resources. Chemical engineers play a key role in addressing water scarcity due to their expertise in developing intricate water treatment systems. Conventional water treatment employs physical processes such as sedimentation and filtration, as well as chemical processes such as coagulation and disinfection. In recent years, innovative techniques like advanced oxidation processes (AOPs) have emerged, utilizing chemical reactions to break down pollutants, pathogens, and toxins in water.
Desalination, a natural process within the water cycle, involves removing dissolved mineral salts from water. Seawater evaporation leaves behind salt, resulting in the formation of clouds that eventually lead to rainfall. Aristotle noted that evaporated and condensed seawater could transform into fresh water, a concept that Da Vinci found could be harnessed using a simple still. Before the industrial revolution, desalination was used on sailing vessels; however, it was primarily refined in Australia. Currently, desalination provides 95 billion liters of water daily for human consumption. Another desalination technology that leverages chemical and physical principles to purify water is reverse osmosis (RO). RO involves pushing water through a semi-permeable membrane, allowing water molecules to pass while excluding salts and impurities. Thanks to the development of high-performance membranes and improvements in energy efficiency, RO now stands as a more sustainable and cost-effective solution. Additionally, advancements in nanotechnology have led to the creation of nanocomposite membranes with enhanced selectivity and durability. Distillation, on the other hand, entails heating seawater to produce steam, which is then condensed back into liquid water, leaving salts and impurities behind. Advancements in distillation methods, such as multi-effect distillation and vapor compression distillation, have significantly reduced energy consumption and operational costs, making desalination more accessible to underprivileged communities.
While technological breakthroughs provide hope for mitigating water scarcity, it is critical to emphasize the nexus of science and social justice. Access to safe drinking water is more than a technical challenge; it is a matter of human rights and social equality. Impoverished communities often lack the resources to implement and maintain these technologies, perpetuating the cycle of inequity. Initiatives should focus on capacity building, education, and local empowerment to address these issues. Collaboration between governments, non-governmental organizations, and research institutes can result in the creation of community-driven solutions. Furthermore, policies that prioritize equitable distribution of water resources and the needs of marginalized communities are essential.
Water scarcity is a complex challenge that requires a multidisciplinary approach. Chemical engineering developments in water treatment and desalination technologies offer a glimmer of hope for reducing the issue and fostering social justice. As we delve deeper into the chemistry of these processes, we must maintain our dedication to inclusion, sustainability, and human rights. By combining scientific innovation with social empowerment, we can bridge the gap for vulnerable communities and pave the road for a more water-secure and equitable future.
Citations:
Desalination. Desalination – an overview | ScienceDirect Topics. (n.d.). https://www.sciencedirect.com/topics/earth-and-planetary-sciences/desalination
Encyclopædia Britannica, inc. (2023, July 22). Desalination. Encyclopædia Britannica. https://www.britannica.com/technology/desalination
How desalination can help address the freshwater challenge. G. (2022, March 18). https://www.gstic.org/expert-story/how-desalination-can-help-address-the-freshwater-challenge/
Iberdrola. (2021, April 22). Seawater desalination: A method for combating scarcity?. Iberdrola. https://www.iberdrola.com/innovation/desalination
Water and catchments. (2019, July 25). Desalination history. Water and catchments. https://www.water.vic.gov.au/water-grid-and-markets/desalination/desalination-background/desalination-history
