| 摘要 |
<p>Control of lead contamination in residential water supplies is accomplished by cathodic protection of lead-containing piping and lead-containing fixtures. Specifically, a partially insulated wire (3) is inserted into lead-containing service lateral piping (2). Application of a DC current to the partially insulated wire (3) causes the wire (3) to act as an anode and transforms the walls of the pipe (2) into the cathode, thereby protecting against corrosion. Alternatively, a sacrificial anode (14) is inserted into a lead-containing fixture (12). The electrical potential generated by corrosion of this sacrificial anode (14) transforms the walls of the fixture (12) into a cathode, thereby preventing corrosion. Carbonate scaling built-up prior to the initiation of cathodic protection may be removed by temporarily blocking the water pipe and introducing cleaning chemicals.</p> |
