Biological Adsorption for Removal of Hydrogen Sulfide from Aqueous Solution by Live ‎Eisenia Foetida Worms

The increasing human population on earth has increased household waste and wastewater worldwide. Wastewater due to have H2S is often toxic and has a pungent odor. To solve the problem of household waste, it is better to bury household waste and biogas production for consumption as fuel. Natural gas and biogas have H2S. The main purpose of this research was to use Eisenia foetida worms in the H2S removal from solution for performance in water scrubbing gas, biogas, and wastewater purification. The samples were bought from vermicomposting farms in Mashhad City. The tolerance of the worms to hydrogen sulfide was determined. In two identical cylindrical experimental treatments and control, and H2S solution was poured. Live worms were added to the experimental treatment and the H2S concentration was measured at every 30 minutes intervals. Adsorbed capacity and removal efficiency was calculated.  In the experimental treatment adsorption capacity was 66 (mg/g) and the removal efficiency at the end of the test at 220 minutes reached 100%. The results showed that worms can adsorb and remove significant amounts of H2S.