Abstract
The start-up and treatment ability of a stirred tank anammox reactor (STAR) using PVA gel as biomass carrier were systematically investigated. PVA gels, as a new kind of biomass carrier, exhibited satisfactory treatment ability. Experimental results showed that a maximum nitrogen removal rate of 4.3kg/m3/d was achieved after 305 days of operation. Different operational strategy indicated that there was limited effect of influent concentration on the treatment ability of the anammox sludge, while the change of HRT has a positive effect on the treatment ability of the anammox sludge. The effluent SS level was relatively low, with an average of about 10mg/L, which indicated the slight loss of anammox sludge. Stereo microscope and SEM observation showed that anammox sludge gradually and firmly attached on the surface of the PVA gels, showing the effectiveness of PVA gel as the biomass carrier of anammox sludge. DNA analysis showed anammox bacterium KSU-1 was dominant in the annammox reactor, further confirming the effectiveness of using PVA gel bead to culture anammox bacteria.
