糠醛生产废水废渣的资源化利用研究进展

摘要

The temperature and acetic acid content of wastewater from furfural production were 95-99℃and 1.43%-2.84%. Moreover, the chemical oxygen demand ( COD), biochemical oxygen demand ( BOD) and BOD/COD of raw wastewater were 10 000-20 000 mg/L, 2 500-3 000 mg/L and 0.20-0.25, respectively.The sustainable development of furfural industry was seriously restricted by the difficult biodegradation of furfural wastewater .Several newly-developed extraction agents in combination with multi-stage counter current extraction could recycle more than 90%of acetic acid in furfural wastewater and the extraction efficiency could reach 97%-99%.The calcium oxide neutralization-double effect evaporation-distillation technology has been applied to neutralize acid of wastewater .The waste heat energy was recovered and a lot of acetic acid of wastewater was also recovered efficiently to produce environmental protection type calcium magnesium acetate ( CMA ) snowmelt agent .This technology could greatly reduce the production cost of traditional CMA snowmelt agent and realize the zero discharge of wastewater .After high temperature fermentation , furfural production waste residue was made into the organic fertilizer , or lignin and fiber ethanol were acquired simultaneously with the production of furfural .And this also showed a good prospect of industrialization .%糠醛生产废水温度达95～99℃，醋酸高达1．43％～2．84％，化学耗氧量（COD）10000～20000 mg／L，生物耗氧量（BOD）2500～3000 mg／L，BOD／COD＝0．20～0．25，生物处理困难，长期以来严重困扰着糠醛生产行业的可持续发展。近年开发出多种萃取剂，回收了糠醛生产废水中90％以上的醋酸，采用的多级逆流萃取，萃取效率高达97％～99％。新开发的氧化钙中和-双效蒸发-精馏工艺技术，中和了废水的酸度，利用了废水的热能，废水中大量醋酸得到资源化利用，制成环保型醋酸钙镁（ CMA）融雪剂，大大降低了传统CMA融雪剂生产成本，解决了数十年来氯化钠融雪剂腐蚀公路设施的难题，废水基本做到零排放。将糠醛生产废渣高温发酵后制取环保有机肥，或在制糠醛时联产制取木质素和乙醇，也已展示出良好的产业化前景。