Algal bioremediation versus conventional wastewater treatment

Abstract

Microalgae-based wastewater (Ww) treatment systems are gaining popularity in recent years and offer a simple and cost-effective tertiary biotreatment process combined with the production of valuable biomass that can be utilized for several purposes. Algal cells can be used to remove carbon, nitrogen, and phosphorus from Ww and aid disinfection due to the increase in pH during photosynthesis, while algae biomass can be used for the production of food, biofuels, and different chemicals., In the current study, the application of microalgae for Ww will be studied, this includes the influence of (1) algal growth parameters, (2) cultivation systems, and (3) Ww quality parameters on this process. The results revealed that algal cultivation parameters have a considerable effect on Ww treatment, most importantly the selection of proper algal strain for specific purposes and nutrient concentration (mainly N and P) in the cultivation media. Open ponds (Ops), Raceways (RP) offer an excellent Ww treatment option and biomass production compared with closed photobioreactor (PBR). The Ww quality parameters play a vital role in the treatment process as the contained Ww constituents can either promote or inhibit algal cells. Filtration and centrifugation are the most promising methods for algal cell harvesting and biofuel production. These results are encouraging for the use of microalgae cultivation technology for Ww treatment.