Nahid Ghobadi
1, Reza Shokooh
1, Ali Reza Rahmani
1, Mohammad Taghi Samadi
1, Kazem Godini
1, Mohammad Reza Samarghandi
1*1 Department of Environmental Health Engineering, Hamadan University of Medical Sciences, Hamadan, Iran
*Corresponding Author: * Corresponding author: Mohammad Reza Samarghandi, Department of Environmental Health Engineering, Faculty of Health and Research Center for Health Sciences, Hamadan University of Medical Sciences, Hamadan, IR Iran. Tel: +98-8138380026, Fax: +98-8138380509, , Email:
mr.samarghandi@umsha.ac.ir
Abstract
In this study, the performance of a pilot-scale vermifilter (VF) for the treatment of hospital wastewater using the earthworm species
Eisenia fetida was evaluated. The earthworms’ gut acts as a bioreactor and can ingest the wastewater solid and liquid organic wastes
and expel these as vermicompost. A pilot-scale vermifilter was installed and operated for 133 days in one of hospitals in Hamadan city;
the designed system was fed with the influent passed through coarse and fine grillage and the sedimentation tank of the hospital’s
sanitary collection system. In order to study the efficiency of the system, the variations of pH value, chemical oxygen demand (COD),
biochemical oxygen demand (BOD5), and total suspended solids (TSS) were measured. In addition, a conventional geofilter (GF)
without Earthworm was used as the experimental control. The vermifiltration caused a significant decrease in the levels of COD
(75%), BOD5 (93%), and TSS (89%) as well as neutralized pH in the wastewater. Also, these contents in the geofilter were observed to be
65%, 71%, and 71%, respectively. The vermifiltration technology can, therefore, be applied as an environmentally friendly method for
hospital wastewater treatment.