| Mechanical Descaling of Wire Rod Coils | France | 1979 | Full scale |
MANUFACTURE OF FABRICATED METAL PRODUCTS # 13
Background
This case study illustrates a new technology of mechanical descaling of wire rod coils, which reduces waste.
Cleaner Production principle
New technology
Cleaner Production Application
The standard technology dips wire-rod coils in a hot acid bath, rinsed and then treated with lime in order to neutralize any trace of acid. In the new process wire-rod is descaled by roller-binding. It then goes through a sanding chamber where it is sand blasted. The surface quality thus achieved permits wire- drawing. The low-waste dry and wet processes require 0.5 GJ per ton of descaled wire-rod versus 2.35 GJ in the standard technology.
| Capital cost | FF 500,000 (1979 figures) |
| Operation/maintenance | FF 22.9 per ton (1979 figures) |
| Disposal & feedstock | FF 26.6 per ton descaled |
Environmental and Economic Benefits
| Feedstock reduction | 3.99 m3 of water per ton of descaled wire-rod |
| Waste production | 5 Kg of scale |
| Impact/problems | Greater safety and reliability due to the absence of hot acid. |
Constraints
None reported.
Contacts
Compendium on Low and Non-waste Technology, United Nations Economic and Social Counsel, "Mechanical Descaling of Wire Rods by a Dry or Wet Process", Monograph ENV/WP.2/5/Add.68
Review Status
This case study was originally abstracted for the US EPA Pollution Prevention Information Clearinghouse. It underwent a UNEP IE funded technical review in 1994 for quality and completeness. It was edited for the ICPIC diskette in July 1995.
Subsequently the case study has undergone another technical review by Dr Prasad Modak at Environmental Management Centre, Mumbai, India, in September 1998.