Environmental

Liquid Waste Stream Remediation

Condensate Stripping

Steam stripping is recognized as an efficient method for the removal of methanol and Total Reduced Sulphur (TRS) compounds from foul process condensates, reducing biological and chemical oxygen demand (BOD and COD) in effluent streams.

The A. H. Lundberg Systems stripping system includes a feed tank, fibre filter, condensate preheater, stripping column with rectification section and a reflux condenser. Optional system enhancements can include the selective condensation and storage of liquid methanol from the stripper off gas for use as an auxiliary fuel. Also see methanol purification below.

Methanol Purification System

The A.H. Lundberg Systems methanol purification system is a unique two-stage stripping process that produces streams of high purity methanol, de-hydrated stripper off-gas (SOG), and high quality stripped water from kraft pulp mill foul process condensates.

As separate products, both the methanol and the stripped condensate contribute additional operational and economic value to the plant. Reuse of the stripped condensate reduces plant makeup water requirements and reduces the overall water load to the downstream treating facilities.

The recovered methanol is of sufficient purity to use as fuel for a chlorine dioxide generator. Methanol recovered from the SOG generally exceeds the total plant requirements of methanol to fuel the chlorine dioxide generator. Surplus methanol may be recovered as a salable product or stored as a liquid and burned as an auxiliary fuel.

Methanol recovery also leads to more efficient incineration of the de-hydrated stripper off-gas (SOG). Problematic water has been removed, and lower mass load of SOG is delivered to the point of incineration, allowing use of smaller diameter piping.