LILEXliquid-liquid extraction

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KVT has been engaged for decades in the development of solutions tailored to individual customer requirements for the treatment of industrial effluents. For the pulp industry KVT has developed a technology for furfural and acetic acid recovery.
In an average leaf wood pulp about 10.000 to 50.000 tons of furfural and acetic acid are burned yearly together with the sulfite waste liquor.
With the LILEX technology the vapor condensates are subjected to a liquid/liquid extraction and the extracts furfural and acetic acid are purified by fractional distillation. Among the most economical solutions for the recovery of furfural and acetic acid, the process allows vapor purification of condensates of up to 90 %. LILEX technology offers economical advantages while protecting the environment by reducing emissions.

The technical process is as follows:
The furfural enrichment plant increases the furfural content of spent liquor by transforming the xyloses into furfural. This transformation takes place in a reactor under precisely defined conditions (temperature, pressure, reaction time) after heating up in a heat exchanger system.

The furfural still contained in the thin liquor leaving the reactor is subsequently (owing to its high volatility) vaporized and taken up by the vapor condensate in the evaporation plant. The furfural contained in the vapor condensate is obtained by extraction or distillation. The technical advantage of the extraction method is a reduction of energy consumption by about 80 % compared to the conventional method of distillation.

By use of a special extraction agent, some 90 % of furfural and acetic acid is extracted from the vapor condensate. In distillation units, the furfural and acetic acid are separated from the extraction agent to obtain a high purity level The product range includes plants for both processes (extraction and distillation). The optimum plant configuration for a specific purpose is supplied according to individual requirements.

• Recovery of valuable raw materials as furfural and acetic acid
• Cut down on expenses for wastewater treatment plant
• Optimized energy consumptions

• Pulp industry