Moringa oleifera-mediated coagulation of textile wastewater and its biodegradation using novel consortium-BBA grown on agricultural waste substratum

Coagulation-flocculation treatment for batik effluent as a baseline study for the upcoming application of green coagulants/flocculants towards sustainable batik industry

The batik industry has been one of the main family businesses in most of the east-coast region of the Malaysian peninsula for many years. However, appropriate water treatment is still a major challenge for this industry. Stringent laws introduced by the Malaysian authorities and the intention to protect the environment are factors that drive researchers to search for suitable, appropriate, affordable and efficient treatment of batik wastewater. Treatment research on batik wastewater is still lacking and coagulation-flocculation treatment using alum was introduced and chosen as a stepping stone toward the selection of green coagulants. This study aimed to determine the best conditions for alum flocculation-coagulation using a standard jar test method. Four main factors were investigated: alum dosage (0.1-3.5 g/L), pH (4-11), settling time (0.5-24 h) and rapid mixing rate (100-300 rpm). Results obtained were further analysed statistically using SPSS software prior to determining the significant effect of variable changes. From this study, the best conditions for batik wastewater treatment using the flocculation-coagulation process were found to be at alum dosage of 1.5 g/L, pH 8, 4 h settling time and a rapid mixing rate of 100 rpm. Chemical oxygen demand (COD), turbidity, colour and total suspended solids (TSS) were removed by 70.7, 92.2, 88.4 and 100%, respectively, under these conditions. This study showed that batik wastewater can be treated by the coagulation-flocculation process using chemical means of alum. This indicates the need for forthcoming developments in natural-based-coagulant-flocculants toward the sustainability of the batik industry.

Fish Food Production Using Agro-Industrial Waste Enhanced with Spirulina sp

The supply of animal feed is one of the main concerns of producers in the aquaculture industry, including aspects such as the cost of fish flour and its nutritional balance. The aim of this study was the preparation of a pellet-type fish food using powdered Spirulina sp. cultivated as a protein source supplemented with agro-industrial waste, and its evaluation to comply with the necessary parameters for the elaboration of extruded pellets. Spirulina sp. was cultivated in a photobioreactor at a volume of 50 L, separated by decantation and dried. The proximal characterization was 6.79% ± 0.05 moisture, 6.93% ± 0.01 ash, 66.88% ± 0.33 protein, and 5.50% ± 0.26 fat. Subsequently, flours were prepared using cassava leaves, gliricidia leaves, and rice husks. The results for the cohesion showed that the flours obtained to comply with the necessary parameters for the elaboration of extruded food. The fish feed was prepared in pellet form using the formulation for fattening Tilapia: Spirulina sp. (20%), cassava leaf flour (50%), gliricidia leaf flour (20%) and flour of rice husk (10%). Floatation analysis showed that 60% of the pellets floated for more than 40 min, and 80% retained their shape for 4 h. The results show that the obtained product can be used as fish feed, due to the lowest disintegration, together with its great capacity for water absorption and especially, its greater flotage due to the expansion effect, are physic characteristic determinants so that the fish has more time to consume extruded diets and avoid losses.

Moringa oleifera seed defatted press cake based biocoagulant for the treatment of coal beneficiation plant effluent

This study proposes a unique way of preparation of biocoagulant from Moringa oleifera defatted seed press cake. The press cake used in this study is a waste material produced as a by-product during cold press oil making from Moring oleifera seeds. The prepared Moringa oleifera seed defatted press cake based biocoagulant was found more effective than presently used metallic and polymer-based coagulants and flocculants for removal of fine particles of colloidal size from the effluent generated in the process of coal beneficiation. The detailed characterization of Moringa oleifera defatted seed press cake and the prepared biocoagulant for Particle size, Field Emission Scanning Electron Microscopy, Energy Dispersive X-Ray analysis, Zeta Potential, Fourier-transform Infrared Spectroscopy, etc. was done. The biocoagulant has been found effective in 97.4% total suspended solids removal and 97.48% turbidity removal from coal beneficiation plant effluent. The biocoagulant has been found to work satisfactorily under high fluxes of turbidity and total suspended solids with high removal of fine particles. The age of biocoagulant had negligible effect on fine particle removal efficiency (97.4% for fresh to 95% for 3-week-old biocoagulant). Field Emission Scanning Electron Microscopy analysis reveals considerable increase in flocs size from 198 nm to a 20 μ size well-developed flocs. The biocoagulant has proved as an efficient substitute of the metallic and polymer-based coagulants for the efficient treatment of coal beneficiation plant effluent.

Influence of bionanoparticles to treat a slaughterhouse wastewater

Treatment of effluents from animal slaughterhouse industries is indispensable, standing out coagulation/flocculation/sedimentation processes. Bionanoparticles (BioNPs) (nanoparticles (NPs) functionalized with Moringa extracts (MO)) were studied as an alternative natural coagulant that would contribute to the microbial load reduction, without increasing the treated effluent toxicity. MO extracts were prepared with different salts, and then, in a kinetics study, different NPs mass and coagulant dosages were evaluated. In the best-defined conditions, microbial load, toxicity tests for the bioindicator Lactuca sativa, and NPs reuse evaluation were performed. Removals of 96.14% turbidity and 43.63% UV254nm were achieved when using 500 mg L-1 of BioNPs containing 60 mg of NPs for every 20 mL of MO extract prepared with 0.1 M CaCl2. The BioNPs with an external magnetic field also decreased the sedimentation time from 140 to 10 min compared to MO, and the process efficiency did not expressively decrease after reusing the recovered NPs. Through toxicity tests, BioNPs were not considered to leave residuals toxic to the Lactuca sativa in the treated effluent. Besides, the microbial load reduction was 97.33% for heterotrophic microorganisms and total mesophiles and 99.25% for moulds/yeasts. Therefore, a satisfactory primary treatment was achieved, contributing to the sustainability of industries.