Pollution
Humain
Environnement
Economique

At around 3 p.m., a spill of bentonite and carbon black from an automotive parts foundry polluted the Loire Canal. The spill measured 20 m long and 15 m wide. The canal’s operator interrupted navigation and the emergency services deployed a floating containment boom to contain the spill. A specialised company began pumping the product in the late afternoon. The next day, no trace of pollutant was detected and the emergency services removed the boom.

The release of fines was due to a faulty compressed air solenoid valve on the dust collector’s unclogging system, which had not closed. This leak resulted in an accumulation of fines along the auger, causing the electric motor to trip. The operators in charge of managing this motor failure were not well trained in dust collector troubleshooting operations. They put the auger back into operation which resulted in a significant discharge of the fines that had accumulated in the discharge cone. The downstream piping has the peculiarity of being bent, which led to the cone becoming clogged. The operators then decided to disconnect a hose between the dust collector and the discharge cone, resulting in a large amount of fines being discharged onto the ground. These fines then flowed through the gaps in the floor and cladding onto the banks of the canal below.

Following this accident, the operator undertook the following actions:

  • replacement of the solenoid valves in the dust collector’s cleaning system;
  • implementation of rotation control on the auger;
  • modification of the configuration of the fines discharge pipe;
  • training of the troubleshooting personnel in the operation of the dust collector and creation of a response flowchart following a differential pressure defect on the dust collector.