Approximately 15% of the world’s population, significantly in low-income developing countries, endure the issue of potable water. Innovations and research continue today to produce new portable, cheap and efficient devices and methods to treat contaminated drinking water for poverty-stricken communities in such countries.
Natural and anthropogenic pollution contribute highly to the inaccessibility of clean drinking water to a large proportion of the population. Contamination of water due to the presence of pathogens, pesticides, fertilisers and chemicals can lead to serious health problems which can further weaken the economic and social sustainability of the country as more money is funded into treating these diagnoses. Considering these countries’ economic instability, it’s important to develop simple and low-cost yet innovative water treatment devices which focus on filtration, solar and herbal water disinfection and arsenic removal technologies.
Figure 1 displays the most common water treatment used to make it potable. For example, the initial stage of the treatment involves passing the abstraction point water through a screen and coarse filters. It is contained in a storage tank where it is naturally sedimented and UV light can break down pathogens. However, in developing countries, the natural scarcity of a water source in specific zones makes it difficult to widely provide drinking water as floods (leading to the contamination of rivers and large dams) can cause source-rector challenges. Additionally, investing in water infrastructure, particularly on a large scale, can be difficult for a country with a low GNI as thorough management of solid waste and waste water is required to improve the quality of their potable water.
However, rural communities who do not have access to this centralised water supply remain numerous in the developing world. An example of an inexpensive, portable apparatus designed to treat contaminated drinking water for poor areas in developing countries is the SODIS (SOlar DISinfection) bottle which destroys microbes in water using the heat and ultraviolet from sunlight. This device, however, is a short term solution due to its limited durability and scientists are currently unaware of the duration required to disinfect the water particularly if it’s very turbid. Thus, this design inspired chemical engineer Dr Emma Emanuelsson and a research team from the University of Bath which consists of undergraduates from the departments of social and policy sciences, civil engineering and mathematical sciences to create a more durable alternative. This multidisciplinary approach according to Dr Emanuelsson can ‘provide those most in need with safe, clean drinking water’ and she described it to be ‘an exciting prospect’. The device is to be made up of a black plastic slab with channels running across the surface, where the water runs into. The black plastic absorbs heat from the Sun causing the water to rise in temperature to kill the microbes, simultaneously absorbing the ultraviolet rays from the Sun. The prototype is 40cm x 40cm with moderately deep channels and curved corners to produce slight turbulence, yet there is a balance to guarantee the light from the Sun remains able to penetrate all the way through the water.
This device is primarily focused on rural communities in sub-Saharan Africa where there is a lot of direct sunlight and a lack of clean drinking water access for the inhabitants. It requires no power source which is favourable for these areas where access to electricity is very limited and has great durability. Additionally, it has been predicted to create almost 35 litres of clean potable water on a daily scale; the recommended amount for basic sanitation by the World Health Organisation is 50 litres a day. Nevertheless, for the majority of African deprived communities, the local people at most receive 30 litres of water for their personal hygiene, drinking water and domestic utilisation a day. The aim for every single apparatus is to be created from a biodegradable plant-based plastic (polylactic acid- PLA) to reduce the land taken up in landfills and limit the extraction of crude oil to produce non biodegradable plastics such as polyethylene. This would weigh about 3kg with a cost of approximately £5.00 per unit as locally trained workers in these communities are expected to produce 10,000 units annually.
Although it is not a large scale approach, this example demonstrates the necessity of access to safe, disinfected water in poorer communities where their rural lifestyle is centred around it. Clean water productivity is required in the agricultural sector, personal cleanliness, domestic use and most importantly for the millions of people who are deprived of drinking it. Poor access to water and the lack of water resource management in such areas needs to be addressed whilst maintaining the affordability of it to be sustainable. An integrated approach between developed countries and the developing world is necessary in developing potable water that is safe and economically and environmentally sustainable. Education of contamination and distillation through projects such as the design from Dr Emanuelsson’s team is very important for these communities to ensure their safety and promising health.
- New way to clean water in developing world- by Helen Tunnicliffe https://www.thechemicalengineer.com/news/new-way-to-clean-water-in-developing-world/