Abstract

Produced water (PW) is the effluent generatedduring oil mining and extraction. On average, for every barrelof oil, 4-5 barrels of PW are generated worldwide. The presenceof various contaminants in PW makes it toxic. Disposal ofuntreated PW into oceans and water bodies can cause adverseeffects on human health and the environment. Taking intoaccount the large volumes of it being generated, and its effectson the environment, proper treatment is required before reuseor disposal. Microalgal treatment is an effective method for thebioremediation and biodesalination of produced water whenacclimatized algal biomass is used for the treatment. However,harvesting this acclimatized high-value algal biomass for reuseand recycling, and the reuse or disposal of produced water ischallenging. Thus, the immobilization of microalgae intopolymer matrices will be beneficial in solving both problems.Different polymers, both natural and synthetic are used asmatrices for immobilizing cells. In this study, experiments weredone with alginate and chitosan matrices to immobilize algae.Microalgae enriched and grown in wastewater wereacclimatized to three different produced water samples byprogressive adaptation in a steadily increasing ratio ofproduced water. The algae which could adapt and grow in thehighest ratio in minimum time were immobilized and used forbioremediation of produced water. The study also evaluated thestability of the matrix in produced water and the treatmentefficiency. The results of the study led to the conclusion thatproduced water is highly toxic for the stability of alginate andchitosan matrices. A more stable matrix has to be determinedand experimented with for immobilizing algae and treatment ofproduced water.