The invention relates to a process
coupling catalyzed iron with a
biological filter. A catalyzed iron reaction tank is arranged in front of the
biological filter. A catalyzed iron
bed is arranged at the upper part of the
biological filter, an aerator
pipe is arranged at the lower part of the biological filter, and a water inlet is formed at the bottom of the biological filter. A PVC (
polyvinyl chloride) packing layer is arranged at the upper part of the biological filter, the aerator
pipe is arranged at the lower part of the biological filter, and the bottom of the biological filter is connected with a water outlet in one side of the top of the catalyzed iron reaction tank. The process comprises the following steps:
refractory industrial
wastewater enters the catalyzed iron reaction tank, the pH value of in-water is controlled within a range of 5.0-10.0; the inner part of the catalyzed iron reaction tank adopts the aerator
pipe for
aeration, the concentration of dissolved
oxygen is controlled within a range of 0.01-5.0mg / L, the stacking density of the catalyzed iron
bed is controlled within a range of 0.1-0.5kg / dm-3, and the
hydraulic retention time is controlled within a range of 0.5-1 hour; out-water of the catalyzed iron reaction tank is used as the in-water of the biological filter to carry out biological treatment, and the pH value of the in-water of the biological filter is controlled within a range of 6.0-8.0; the inner part of the biological filter also adopts the aerator pipe for
aeration, and the concentration of the dissolved
oxygen is controlled within a range of 2.0-4.0mg / L-1; and the stacking density of PVC packing in the biological filter is controlled within a rang of 0.01-0.05kg / dm-3, and the
hydraulic retention time is controlled within a range of 2.0-4.0 hours. The out-water passing through the biological filter is drained into water. The COD removal rate of the industrial
wastewater subjected to the purifying and biochemical treatment by the method can reach 50 percent, and the new standard is stably reached.