The Research Of The Dyeing And Printing Wastewater Treatment Using Microelectrolysis Technology And Its Engineering Application

As the major emissions of the industrial waste water,the dyeing and printing wastewater brings great pressure to the environment everyday if it isn't treated reasonably.And, the dyeing and printing wastewater is of high quantity, instability, complex composition, high chroma and high COD.So it is a big problem in the treatment of industrial wastewater. In addition, the requirements of people on the clothing, textile are increased day by day, the dye and the auxiliary are also constantly changed.The natural fiber is gradually replaced by the chemical fiber.So the hard biodegradable polymers like the PVA slurry and the rayon hydrolysates flow into the wastewater.It lead to the increasingly high demand with wastewater treatment technology. Taking the practical engineering cases and consulting literatures, chroma control and COD index has been the trouble of the dyeing and printing wastewater, according to the requirements of the owner and the actual need, the main goal of this project is to control COD and chroma.Microelectrolysis technology is appeared under the requirement of the industry. It is promoted rapidly beacause of the advantages of less investment, low operation cost, obvious effect, covers an less area. Microelectrolysis technology used in this project is different from the common iron carbon microelectrolysis technology, but there are some similarities.They utilize the environmental resources—wasted iron to produce Fe²⁺ in the waste water to make certain flocculation and part the chromogen in the electrolysis.But the iron carbon microelectrolysis technology effect has certain limitation. Microelectrolysis technology of this project is powered,so it enhanced the discharge function and the electrocoagulation effect, and it can automatically exchange the positive and negative in order to prevent the electrode covered by pollutants.During the pilot test of this project, we tested the removal effect of COD and chroma in three kinds of water conditions :?1?The raw water as inlet water.?2?The regulation pool water of original process as inlet water.?3?The tail water of original process as inlet water. Adding certain amount of H₂O₂ to the microelectrolysis pool can produce Fenton effect,the effect of the composition of microelectrolysis and Fenton technology is very good.But we can't control the amount of the Fe²⁺ in this test,so it needs to improved.Comprehensive comparison, whether the COD removal or color removal, the first situation is better than the second kind.When the regulation pool water of original process as inlet water, the water is more stable, the COD and color removal is also more stable,and the final effluent is closer to the standard value.