Strategies of Utilising Agriculture Wastewater for Microalgae Cultivation and Its Possible Applications: A Review

Microalgae have been found to have high prospects in wastewater treatment, particularly from agriculture. However, the uneconomical algal medium growth has become the major disadvantaged in algal industry. Multiple attempts includes the development of microalgae phycoremediation technology has been integrated into wastewater treatment to reduce the cost of expensive wastewater remediation. Utilising wastewater as a low-cost nutrient medium offers a synergistic effect of wastewater nutrient removal and co-production of valuable biomass simultaneously. This paper is mainly focused on potential, ability, strategy, application (i.e., palm oil wastewater), limitation and challenges of microalgae in agricultural wastewater treatment using phycoremediation. The understanding of cultivating microalgae using agriculture wastewater shall promote the utilisation of wastewater more sustainably in the future. The possible solutions in the application of microalgae for aquaculture and agriculture sector is also discussed in this review. Overall, the utilisation of wastewater in media cultivation for microalgae is restricted due to the expensive treatment and safety concern. However, this pitfall can be reduced in the future together with a further intensive scientific study, advanced technology, better management system and applying better standard protocol.

Optimization of Oil Removal by Sugarcane Bagasse using Response Surface Methodology

Oily wastewater is one of the environmental concerns nowadays. The seriousness of oil pollution problem comes in sync with the expansion of oil exploration and production activities, as well as industrial growth around the world. In this study, the ability of sugarcane bagasse in removing oil in synthetic oil wastewater was investigated. Parameters affecting oil removal such as concentrations of synthetic oil wastewater, biosorbent dosage and contact time were optimized using Response Surface Methodology (RSM) via Box Behnken Design. Sugarcane bagasse showed excellent efficiency in removing oil with percentage removal up to 98.73% at 1.3 h contact time with 3.06 g of biosorbent dosage and 16.9% of synthetic oil wastewater concentration. The use of sugarcane bagasse in removing oil in water was successfully prove in this study.

Performance of Horizontal Roughing Filter for Colour Removal of Palm Oil Mill Effluent Using Natural Adsorbent

Palm oil wastewater treatment was investigated via a filtration process using raw and calcinated limestone. The column studies were conducted using different limestone sizes (4, 12, and 20 mm), calcination temperature (800°C and 600°C) and various filtration rates (20, 60, and 100 mL/min) and a comparison was made with raw limestone under similar conditions. The response surface methodology using central composite design was employed to optimize the process parameter. The experimental data was analyzed via the analysis of variance to identify the interaction between the parameters and the dependent parameter. The results showed that the colour removal increased with an increase in temperature (800 ºC) for filtration rate of 20 mL/min, the retention time of 317 min and the smaller size (4 mm) of limestone and decreased with an increase in the filtration rate and size of raw limestone. Based on the achieved results, the optimum condition for colour removal was at temperature 800°C (61%), 600 oC (56%) and raw limestone (49%) respectively with the same experimental setup (flow rate of 20 mL/min and limestone size of 4 mm). According to the statistical analysis, quadratic models demonstrated significant values (0.000) for the response (colour). Freundlich and Langmuir isotherms also provided good correlation coefficient for the colour removal. The data conforms to the Langmuir isotherm with the best fit model (R2 = 0.7).