Research on Toxicity Character of Cathode Ray Tubes Using Modified Dynamic Toxicity Characteristic Leaching Procedure

摘要

Cathode ray tubes (CRTs) present a disposal problem because of their large magnitude and their role as a major source of lead. Toxicity Characteristic Leaching Procedure (TCLP) is used to determine whether a solid waste is a hazardous waste. A dynamic leaching procedure with series of leaching solutions was developed to evaluate the leaching toxicity of CRT glass in the environment. Lead was found to continuously leach out over the entire 60-days period. The leaching rate was largely affected by the leaching solution. Using TCLP extraction fluid as leaching solution, leachate lead concentration was fluctuated between 5.8 and 6.2mg/L, and the cumulative amount of lead over the test period was 0.36g. By using leaching solutions which simulating acidic, salt, neutral, and alkaline condition, the average lead concentration of leachate was 0.57, 0.38, 0.27, and 0.19mg/L respectively. The result showed that CRT glass had lead leaching toxicity character. Waste CRTs would pollute the environment if they were disposed in landfills or discarded in the environment. Collecting and recycling waste CRTs properly is important for the protection of the environment and human health.