Ceramsite-Vermifilter for Domestic Wastewater Treatment and Reuse: An Option for Rural Agriculture

A lab-scale vermifilter for domestic wastewater treatment was evaluated to the operational characteristics of the ceramsite-vermifilter. The effective removal rates of COD, NH4-N and TSS in the vermifilter were 50.9 ± 6.9%, 69.3 ± 4.9% and 91.9 ± 1.8%, respectively. Microscopic observation of the vermifilter system showed that in the biofilm, zoogloea, rotifer and vorticella were observed, which indicated the good quality of effluent. The key species, the earthworm Eisenia fetida, decomposed the organics in the wastewater and also devoured the solids synchronously. The vermifiltration technology is a cost-effective for wastewater treatment, and the effluent could reach the latest standards of irrigation water quality in China, and could be used for crop irrigation without much concern for infection by sewage-borne pathogens.