DRAFT ONLY; TO BE FINALISED

DRAFT ONLY; TO BE FINALISED

2.1 CERAMIC FILTER WITH SOLAR PUMP (CHRISTOPH BONTRUP)

2.1.1 DESCRIPTION

A ceramic sawdust filter will enable the community of Brewarrina to utilise the Barwon river and turn it into potable water. Currently, the river water is not potable. Especially during the dry season when water levels are low, and the water is brown (McPhee, 2020). Figure 1 shows the setup of this project. It utilises solar power to pump river water through a filter into a storage tank. This system is electricity grid independent, as it purely depends on solar power. This allows it to be used in remote areas, where it would be too expensive to run traditional power lines. Solar panels harvest the suns energy and transform it to electricity which is stored in 12V Batteries. Thereby allowing the system to run dur cloudy days or at night. Contaminated river water is pumped through a filter and stored in a storage tank and available for use.

2.1.2. SPECIFICATIONS

The system consists of three main components. Firstly, the power generation and pump, secondly the water filter and lastly the Control Unit and tank. Each component is explored in detail below.

2.1.2.1 POWER GENERATION AND PUMP

The power generation of this system relies on solar panels. Between 1991 and 2010, Brewarrina had a mean of 178.5 clear days per year (Bureau of Meteorology, 2023). With a modern solar system, this will be sufficient to supply enough electricity for a small pump facility. The system can be implemented on a small scale first, and then repeatedly upgraded as needed. But how many solar panels will be needed? Given a standard solar panel wattage of 250W, 5 solar panels would be sufficient to power this system.

2.1.2.2 WATER FILTER

The water filter in this system can mostly be constructed by locals from local materials. To avoid any larger objects (such as branches, fish, etc) from entering the pump system, a coarse wire mesh is installed on the entry point of the pump hose.

The filter assembly consists of two filter tanks with decreasing diameters of the filter mediums. Thereby filtering larger impurities in the first tank while filtering out finest particles and bacteria in the second tank.

As visible in Figure 1, the two tanks are arranged such that water flows by the force of gravity from the first filter into the second filter. Backwashing the filters to clean them from the impurities needs to be performed in set intervals. These intervals are triggered by pressure sensors and controlled by a PLC.

2.1.2.3 CONTROL SYSTEM AND TANK

The pressure in the system is monitored by the control system. Multiple water quality sensors and pressure sensors are installed to detect any changes in water quality. For example, the cleanliness of the filters can be monitored by comparing the pressure in the pipe system before and after the filters. If the pressure difference exceeds a setpoint, the backwash cycle is triggered. This reverses the water flow and temporarily flushes water in reverse through the filters to wash out impurities. PLCs and water sensors are inexpensive, as entry levels can be purchased for under $1000. The water tank in this system is a sheet metal tank, available as a pre-made item. A concrete base needs to be poured and the tank installed on the cured concrete. The tanks are durable yet inexpensive.

2.1.3. BENEFITS

There are multiple Benefits and Impacts to this design. The first clear benefit is providing more safe, potable water for the Brewarrina community. Clean drinking water is a necessity for any being. Secondly, clean water eradicates waterborne diseases such as Diarrhea or salmonellosis. Prolonged exposure to contaminated water can have life-long health impacts (National Institute of Environmental Health Sciences, 2022). Thirdly, clean water improves the sanitation of everyone in the community. Besides these clear benefits, there are also several impacts on the community.

A positive impact of this design is the fact that Brewarrina will become independent of the water grid. Currently, Brewarrina is supplied by an Artesian bore which was installed from 2002 to 2004 (Brewarrina Shire Council, 2023). Another impact is the ability to utilise a resource that is currently unusable, the polluted river water. Using the river water will relieve the artesian bore and increase its lifespan. Lastly, the community can use excess electricity from the solar system for other applications. This could include LED street lighting or suppling the community hall with electricity.

This design solution is very environmentally appropriate, as it is utilising renewable energy and supplies the shire of Brewarrina with water. There are challenges for the Aboriginal community as it will affect the local river system, which will be further explored below in chapter Constraints.

Multiple guiding principles are adhered by in the development of this application. Fundamentally, the Health and Safety of the community is improved by improving the access to safe drinking water. Furthermore, the Appropriateness of this system is given by the fact that all humans need drinking water. No life is possible without water. Lastly, the guiding principle of Environmental Health is followed closely as the system is carbon neutral once it is installed. All energy is supplied by the solar panels, no fossil fuels are necessary. However, some constraints exist and are laid out below.

2.1.4. CONSTRAINTS

As to any implementation, there are constraints or drawbacks. As mentioned above, the first negative aspect of this application is the impact it has on the Barwon river. This river has been used by Aboriginals for thousands of years, therefor any impact on it must be carefully considered. Another constraint is the technical complexity of the solution. Locals must be trained in the use and troubleshooting of the system. Any interruptions to the water supply must be repaired as quickly as possible to avoid serious consequences. However, local electrical contractors could be tasked with the periodic maintenance of the filter system.

References

McPhee, E (2020, February 19). Life flows downstream: Locals catch fish and celebrate along the banks of the Barwon River as it starts flowing again after severe drought. Daily Mail Australia.

https://www.dailymail.co.uk/news/article-8018477/Water-flows-Barwon-River-Brewarrina-battling-against-drought.html

Bureau of Meteorology. (2023). Climate statistics for Australian locations Monthly climate statistics. Australian Government. http://www.bom.gov.au/jsp/ncc/cdio/cvg/av?p_stn_num=048015&p_prim_element_index=0&p_comp_element_index=0&redraw=null&p_display_type=statistics_summary&normals_years=1991-2020&tablesizebutt=normal

How much water per day

https://www.hunterwater.com.au/our-water/water-supply/water-in-the-lower-hunter/how-much-do-we-need

National Institute of Environmental Health Sciences (2022). Water related illnesses Climate change and Human Health. National Institutes of Health.

https://www.niehs.nih.gov/research/programs/climatechange/health_impacts/waterborne_diseases/index.cfm#:~:text=Some%20common%20water%2Drelated%20illnesses,neurological%20systems%2C%20and%20other%20symptoms.

Brewarrina Shire Council (2023). Water & Sewerage. NSW state government

https://www.brewarrina.nsw.gov.au/engineering/water-sewerage.aspx