I want to achieve the removal of E-coli from wastewater for that the temp. required is 72 degree Celsius but my model should be cost effective so for that I want to know other options.
You can use a solar flat collector. Depending on the volume of substance of work to warming to 75 degrees celsius, you determine the area of the flat collector, depending on the solar incidental radiation in the site. For a solar flat collector you can consider an efficiency for the solar thermal radiation depending on his design of solar flat collector.