Using Inlet filters for rainwater harvesting is an important part of debris removal. It has been proven that a sloping inlet filter can efficiently self cleanitself. Brett Martinson and Terry Thomas of the Development Technology Unit School of Engineering, UK completed a study on inlet filter efficiency.
Inlet filter fabric that is stretched flat traps particles and requires cleaning while a filter that is inclined will self clean itself. Inlet filters are also low cost and can be made out a variety of fabrics including silk and muslim as long as they remove the correct level of debris. Muslin outperforms silk but there are also many other materials that will work.
There are only two things to be concerned about when using inlet filters:
- The amount of rainfall you are getting – If you are in a tropical region an inlet filter can become overwhelmed and rainwater will be wasted during heavy downpours. Increasing the catchment area of inlet filteration can make it more efficient.
- Contamination – Though inlet filters a less likely to get contaminated it is always good to remove and clean an inlet filter from time to time. A inlet filter that bows in will eventually clog so again, the inclined filter is a better idea.
Inlet filtration is just one step in a process to remove debris from rainwater, but it is a fact that angled debris removal with low cost fabric works.