| 摘要 |
<p>A method for cleaning diffusion tiles used in the oxygen distribution system of the biofogical treatment ponds of wastewater treatment facilities is disclosed. The build-up of ferric hydroxide scale, which blocks the pores in such diffusion tiles (55), is removed by (1). purging the oxygen distribution system with a nonoxidizing gas such as nitrogen (10), (2) injecting substantially pure HCI gas (11) through the system which removes the scale, and (3) purging the system again with the nonoxidizing gas before resuming oxygen feed. The use of a nonoxidizing purge gas before and after acid treatment prevents severe corrosion in the oxygen distribution system caused by the simultaneous presence of HCI gas and oxygen.</p> |
