| There are more than forty kinds of organic in the furfural wastewater, such as acetum, furfural, alcoholic aldehyde, ketone, ester and so on, in which the major organic is acetum and furfural. The characteristics of furfural wastewater summarized in the paper are high concentration organic, high acidity and debiodegradation. Discharged straightly without being treated, the wastewater can pollute environment heavily and be harmful to human's health finally. Nowadays biodegradation is the most economical and effectual way in kinds of treatments of furfural wastewater. But it has some disadvantages, for example, it has to adjust pH, and some organic isn′t biodegraded. So it is necessary to study a practical and effectual pretreatment of furfural wastewater.The purpose of this research that was focused on the furfural wastewater was to improve the disposal efficiency, save resource and fund. In this paper, the principle, effect factors, development and application of the iron-carbon micro-electrolysis and Fenton process were introduced. Then a new pretreatment of furfural wastewater was brought forward, that was iron-carbon micro-electrolysis, Fenton and coagulation process. The effect on treatment by several factors was studied in this research, and the optimum parameters were also obtained. What is more, the stability of the treatment result and the effect on the biodegradation of furfural wastewater were discussed, too.The process of micro-electrolysis is that using lots of micro-batteries to erode the anode and lead to a series of reactions, and the micro-batteries appear in acidity by making use of the mixture of the anode material and cathode material. So the process of micro-electrolysis is a result by some actions including flocculation, adsorption, deposition, etc. The iron and [H], Fe2+ produced in the reaction are lively, that could change the structures and characteristics of the organic in wastewater, leading to degrade easily. The process of micro- electrolysis has many advantages, such as less investment, low running cost, simple process operation, and high efficiency, etc.In the reaction of Fenton process, it can produce·OH, which is high oxidation and can break most of the complicate organic in wastewater into lots of simple organic and some ultimate degradation. The process can especially be applied to treat the debiodegradation, high concentration organic wastewater, but its cost is high.The water through the actor of micro-electrolysis contains lots of Fe2+, and its pH is improved. So it is advantaged to reaction of Fenton process. If added H2O2 to the water, the organic could be degraded more, which leading to enhancement of treatment effect. What is more, the Fe2+ and Fe3+ can sediment in the form of alkali after adjusted pH. Various inorganic and organic colloidal particles are adhered and settled out in a reasonable time. All of them can reduce the concentration of contamination.The conclusions of the researches:(1) When furfural wastewater passed through, there would be take place a series of reaction of electro-chemical and physical-chemistry in the micro- electrolysis bed which consisted of iron filings and active carbon. And it could dispose contamination effectively and lighten the disposal load of Fenton reactor. At the same time, Fe2+ coming from the process of micro-electrolysis were benefit to the reaction of Fenton by avoiding addition of Fe2+. The reaction of Fe2+ and H2O2 added could produce·OH, which was high oxidation and could break most of the complicate organic in wastewater into lots of simple organic and some ultimate degradation. Through pH adjusted, Fe2+ and Fe3+ transformed to sedimentation in the form of alkali. Various suspensible and colloidal particles were adhered and settled out with some organic. Then the wastewater was purified more. (2) It was practicable to treat furfural wastewater by the iron-carbon micro-electrolysis, Fenton and coagulation process. The treatment results were tested, the removal rate of CODCr was above 50%, and the biodegradation was rising from 0.38 to 0.69. All of them could benefit to the following biochemistry process.(3) The effect of the cathode padding, the granularity of iron filings and active carbon, hydraulic retention time of micro-electrolysis process, influent wastewater pH, the dosage of iron filings, the ratio of iron filings to carbon, the dosage of H2O2, hydraulic retention time of Fenton process, water pH of Fenton process, coagulation pH, hydraulic retention time of sedimentation were studied in this paper. The optimum parameters were also obtained, and the granularity of iron filings and active carbon, hydraulic retention time of micro-electrolysis process, the dosage of iron filings, the ratio of iron filings to carbon, the dosage of H2O2, hydraulic retention time of Fenton process, coagulation pH, hydraulic retention time of sedimentation were 1～2 mm, 2～4 mm, 50 min, 300 g/L, 2:3, 5mL/L, 2 h, 8.5～9, 30 min, respectively. They could lay the foundation of theory for engineering and running.
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