A novel micro-electrolysis reactor bringing iron-carbon filler to cycle flow was developed in this study,
called as an internal circulation micro-electrolysis (ICE) reactor, which can overcome the disadvantage
of conventional fixed bed (CFB) reactor. In order to investigate the performance of the ICE reactor, a prac-
tical dyes wastewater was selected as target wastewater. The removal efficiency of chemical oxygen
demand (COD) and chroma of the CFB reactor with commercial hardening resistance iron-carbon filler
(CRIF) are only 23% and 40%, respectively. However, for the ICE reactor with a common iron-carbon mix-
ture (CIM), the removal efficiency of COD and chroma are 73% and 98.5%, respectively. The improvement
efficiency of biodegradability index of dyes wastewater for the ICE reactor with the CIM is 23 times,
which is about fourfold as much as that of the CFB reactor with CRIF. The ICE reactor with CIM can stably
keep a high treatment performance for 60 days continuous operation. However, the performance of CFB
reactor with CIM decreases sharply. The results indicate that the ICE reactor has an excellent performance
for the pretreatment of dyes wastewater, which should be due to the elimination of hardening, blocking
and inactivation occurring in the CFB reactor with CIM by the circulation action.