Anaerobic water purification systems for sulphate removal/recovery

Sulphate is a common chemical in industry.

Paque focuses with its technologies for sulphate removal and metal recovery on the following applications:

Many pyrometallurgical operations produce gaseous sulphur dioxide that is converted into sulphuric acid. Gas cleaning produces a weak acid as waste, which is often heavily polluted with a variety of metals with a positive (zinc, cadmium, lead etc.) and a negative value (arsenic). Paques tailor-made technologies allow for maximum recovery of valuables and minimal production of waste for disposal.

Sulphate is one of the world’s most widely used commodities. Although not very toxic, excessive discharge of sulphate can lead to ecological problems. Used water in the chemical industry often contains organic material in addition to sulphate. SULFATEQ™ can remove both in the same process, whilst producing elemental sulphur that can be reused for other purposes.

Concentrations of metals like copper, zinc or nickel of just a few dozens mg/L in acid mine or rock drainage can be economically recovered using SULFATEQ™ or THIOTEQ™Metal.

The number of bioleaching operation to release metals from ore and concentrate is growing rapidly. There are a number of reasons why SULFATEQ™ is ideal for dealing with bleeds from the acid recycle in such operations:

  • Converts sulphate into sulphide that can be used to precipitate metals as pure metal sulphides, which are a global commodity
  • Converts excess sulphate into elemental sulphur that can be reused in heap or tank leaching as in-situ acidification agent
  • Converts acid into elemental sulphur
  • Precipitates calcium and magnesium as carbonates that can be used elsewhere in the process
  • Generates reusable water