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Pharmaceutical compounds in wastewater are currently becoming emerging concern as the utilization of drugs in anthropogenic activities. This research analyzed the effectiveness of pilot-scale vertical subsurface flow constructed wetland (VSSFCW) planted with Scirpus grossus using an aeration system for simultaneous removal of ibuprofen, chemical oxygen demand (COD) and nutrients (NH3-N, NO3-N, and PO4-P) from domestic wastewater. The constructed wetland (CW) platforms (500 L capacity) filled with gravel and sand and planted with native species of S. grossus were used to treat pharmaceutical content in domestic wastewater continuously for 21 days. Three experiments were performed with hydraulic retention time (HRT) of 3, 4 and 5 days. Aeration rates of 0, 1, and 2 L/min were employed for each HRT. The combined effect of HRT, exposure period, and aeration to simultaneously remove ibuprofen, organic materials, and nutrients were examined statistically using Two-way ANOVA and Tukey HSD test. Filtration and adsorption mechanisms of ibuprofen compound by sand medium matrix were proven to occur using solid phase extraction method. The removal efficiency of ibuprofen and COD were dependent on the applied aeration and HRT (p

Azadirachta indica, or Neem, is a natural plant commonly used in medicine and pesticides due to the useful compounds it contains. This study aimed to determine the performance of Neem leaves as a natural coagulant in the removal of turbidity, total suspended solids (TSS) and colour from real aquaculture effluent. The experiment was conducted to determine the effect of mass ratio of the TSS (mg)/mass of coagulant (mg) on the removal of turbidity, TSS and colour, in which the ratio is calculated based on the TSS concentration as an index of aquaculture pollution. The experiment was carried out with a ratio range of 0.1 to 1000 mg TSS per mg coagulant and a total volume of 500 mL. The operational conditions were fixed at 180 rpm and 3 min for rapid mixing, 10 rpm and 20 min for slow mixing and settling time from 30 min to 60 min. The results showed a turbidity removal of 82.7%, TSS removal of 81.37% and colour removal of 65.8% at an optimum ratio of 1000 and coagulant dosage of 0.3 mg/L. For comparison, the performance of alum was also tested and showed higher turbidity, TSS and colour removals of 99.7%, 98.8% and 97.3%, respectively, based on the optimum ratio of 1 with a dosage of 362.7 mg/L. Both coagulants showed a similar optimum settling time of 30 min. From these results, it is clearly seen that Neem has a high potential for use as a coagulant, indicating further exploration to optimize the extraction of active compounds from the leaves.

Turbidity is a common pollutant parameter in water and wastewater treatment that can be reduced through flocculation. This research was conducted to characterise and analyse the potential of bioflocculant-producing bacteria isolated from aquaculture effluent. Samples were taken from two different aquaculture farms that represent brackish and freshwater cultures. A total of 21 different colonies were obtained from all samples. Screening of flocculation activity showed the potential of WS5 to be a bioflocculant agent to remove turbidity from artificial turbid water. One variable at a time analysis was performed to assess the capability of WS5 in different initial turbidity and bioflocculant doses. In comparison with low turbid water with 5% v/v bioflocculant dose (in 5000 NTU turbidity), WS5 exhibited better performance in high turbid water, thereby resulting in the most optimum flocculation activity of 72.5%. The increment in bioflocculant dose of up to 10% did not contribute to the flocculation activity significantly. The increment in particle size distribution for the suspension from before to after treatment with bioflocculant provided evidence that the process of flocculation had occurred effectively. Genomic analysis of selected potential bacteria using BLAST and phylogenetic tree has identified WS5 as Serratia marcescens and has been confirmed as a rod-shaped bacterium. FT-IR spectra and zeta potential analysis indicated that the produced bioflocculant is categorised as anionic bioflocculant with polymer bridging suggested as the main mechanism during turbidity removal.

Industrial coffee processing effluents are acidic and have high contents of organic matter and dissolved solids. These effluents can subsequently cause several adverse effects to human health and aquatic life if discharged directly. Unfortunately, very limited research attention has been focused on the treatment of coffee wastewater. This study highlights the application of phytoremediation as a sustainable approach to treat coffee processing wastewater using local plants in Malaysia, namely, Phragmites karka. A continuous reed bed system with a hydraulic retention time of 3 d is operated for 34 d to observe the efficiency of phytoremediation treatment in removing the total suspended solids (TSS) and colour concentration of industrial coffee effluents. This system effectively reduces the concentration of TSS and colour by 95 % and 76 %, respectively. It is proved that the rooting system of the plants helps in terms of removal performance for both parameters when compared to the unplanted system.