Application of nanofiltration/reverse osmosis on treatment and reutilization of metallurgy waste effiuent

摘要

Pollution from metallurgy wastewater containing dangerous heavy metals has always been a serious problem in China since 1990s．The application of nanofiltration(NF)/reverse osmosis(RO)process for treatment of metallurgy wastewater to reduce industrial water consumption and water reuse was investigated．Treated by physical-chemical methods in practical wastewater plant of metallurgy industry,the secondary metal effiuent together with synthetic water were then tested for reutilization by RO and NF membranes in laboratory．Results showed that high salt removal efficiency of RO could reach 97﹪and 79﹪for NF with a relative low COD value of 35 mg L-1 in its permeate．The product water by both NF and RO desalination satisfied the State Reutilization Qualification，but NF should be more suitable for large-scale industrial practice，which offered significantly higher permeate flux at lOW operating pressure and therefore effectively reduced operating costs．