Algal Cultivation for Treating Wastewater in African Developing Countries: A Review

Abstract

The tremendous increase in human population and rapid decline in freshwater resources have necessitated the development of innovative and sustainable wastewater treatment methods. Africa as a developing continent is currently backing on sustainable solutions to tackle impending water resource crisis brought forward by wastewater‐induced environmental pollution and climate change. Microalgae‐based wastewater treatment systems represent an emerging technology that is capable of meeting the new demand for improved wastewater treatment and climate change mitigation strategies in an environmentally friendly manner. This review critically looks at the opportunities of Africa in harnessing and exploiting the potential of microalgae for the treatment of various wastewaters based on their capacity to recycle nutrients and for concurrent production of valuable biomass and several useful metabolites. Wastewaters, if improperly/completely untreated and discharged, simultaneously pollute freshwater sources and present significant health and environmental risks. Nutrients in wastewater can be utilized and recovered in the form of marketable biomass and products when integrated with the cultivation of microalgae. Several valuable bioproducts can be generated from wastewater‐grown microalgal biomass including biofuels, biofertilizers, animal feed, and various bioactive compounds. This biorefinery approach would most certainly improve wastewater treatment process economics, enhancing the technical feasibility of algae‐based wastewater remediation in African countries.

Kinetic and Prediction Modeling Studies of Organic Pollutants Removal from Municipal Wastewater using Moringa oleifera Biomass as a Coagulant

“…However, the applicability of these technologies and techniques are limited in the developing world due to the cost and technical know-how constraints in the procurement of the raw materials and treatment processes required for these techniques [4][5][6]. Moreover, some of these treatment methods use excessive chemicals, generate secondary wastes which are often difficult to treat, and are found to be inefficient in the treatment of municipal wastewater due to the fact of varying forms of pollutants [7][8][9].…”

Utilization of Sugar Factory Pressmud Waste for Upgrading the Efficiency of Waste Stabilization Ponds

“…[ 23 ] Thus, anaerobic treatment has been increasingly used over aerobic treatment for most industrial wastewaters, and this process may continue in the future for domestic wastewater as well. [ 2,24 ]…”

“…[23] Thus, anaerobic treatment has been increasingly used over aerobic treatment for most industrial wastewaters, and this process may continue in the future for domestic wastewater as well. [2,24] In the anaerobic reactors of WWT, including anaerobic lagoons, anaerobic digestion of sludge, and up-flow anaerobic sludge blanket reactors, a reduction in COD occurs by the conversion of most organics into gases mainly containing CH 4 and CO 2 with extremely small amounts of hydrogen (H 2 ) and other gases. Anaerobic decomposition involves a consortium of microorganisms that execute a complex process in a series of interdependent steps.…”

An Overview of the Classification, Production and Utilization of Biofuels for Internal Combustion Engine Applications

“…The challenges associated with 1GB and the 2GB gave rise to the development of 3GB, particularly with regard to feedstock selection. Algae, which is the major feedstock for 3GB, does not interfere with the food chain and requires no land or freshwater for cultivation, either naturally or artificially [134]. Other feedstocks for 3GB include yeast, fungi, and cyanobacteria, while examples of 3GB include bioethanol, vegetable oil, biodiesel, biomethanol, and jet fuels.…”