Design, scaling, and development of biofilters with E crassipes for treatment of water contaminated with Cr (VI)

Abstract

The heavy metal water treatment process is the subject of worldwide research. Chromium (VI) is a heavy metal that is very dangerous to humans due to it being able to alter genetic material and cause cancer. Cellulose is an interesting material for removing heavy metals, and excellent removals have been achieved in many experiments at the laboratory scale. However, scaling these processes to polluting industries is not easy. The objective of this research is to design, scale, and test a biofilter with biomass of E crassipes transformed with iron for treatment of water contaminated with Cr (VI). The biomasses of E crassipes (EC) and E crassipes with iron (EC + Fe) were evaluated at the batch laboratory scale to determine the adsorption capacities through Langmuir isotherms. With these capacities, a mass balance was formulated, obtaining the design equation to build a biofilter at the pilot scale and providing the required amount of biomass from (EC) and (EC + Fe) for the adequate treatment of the Cr (VI) present in the water. The mass, as suggested by the relevant equations, for the greatest concentration of Cr (VI) of 500 mg/L was 42 g together with a flow rate of 10 mL/min for the biomass of (EC + Fe); for the biomass of (EC), the suggested model for the treatment of the greatest Cr (VI) concentration of 500 mg/L was 64 g of biomass together with a flow rate of 10 mL/min. We conclude that the two pilot-scale treatment systems were consistent with the Cr (VI) removal process and that the equation for the design was adequate.