The effects of different plant species in greenwall filtration system on lakewater treatment

It is a concern when 90% of Malaysia's water supply comes from lakes that hold moderate to bad water quality status. Greenwalls are a sustainable modern-day filtration system that proves to be a solution in tackling this lakewater quality issue. To date, there are still questions unanswered regarding the treatment performance of the greenwall filtration system used for lakewater treatment as most research conducted is related to greywater treatment in terms of water quality. Thus, this research aims to investigate the effects of different plant species, filter media ratio and lakewater flowrate on the lakewater treatment performance in a greenwall filtration system. In this work. the plant species between Epipremnum aureum and Mentha piperita as well as the filter media ratio of coir to perlite between 3:1, 1:1 and 1:3, the lakewater flowrate between 15 L/h, 30 L/h and 160 L/h with the highest treatment efficiency for lakewater was investigated and chosen. First, experimental work was conducted with a constant plant species which was Epipremnum aureum and a constant filter media ratio of 1:1 (coir:perlite) to filter lakewater at different flowrates of 15 L/h, 30 L/h and 160 L/h where the initial and final sample of the lakewater was collected. The system ran for 3 hours each time and is referred to as a cycle. The COD and pH of the lakewater were tested before and after each cycle to compare the water quality. This study aims to justify and determine how different plant species as well as the filter media ratio and lakewater flowrate affect the lakewater treatment performance. The results show that Mentha piperita with fibrous root type, filter media ratio of 3:1 of coir to perlite and lakewater flowrate of 30 L/h provide the greatest removal efficiency of pollutants from lakewater. Ultimately, this study will contribute to the ever-growing research of greenwall filtration system for lakewater treatment making this treatment method more feasible for future commercial applications.