Research On The New Technique For Treating ADC Foaming Agents Wastewater

ADC foaming agents wastewater is a high-strength ammonium industrial wastewater containing many complex components, which is very difficult to treat. In this paper, ADC foaming agents wastewater produced by Jiangsu Suopu Chemical Industry Company Ltd. was taken as the research subject and treated by the combined technology (physical chemistry pretreatment technology and biochemistry treatment technology) .This paper involves two experimental phases.In the first experimental phase, ultrasonic stripping technology was adopted to treat the artificial wastewater. Ultrasonic stripping technology is a new-type and high efficient method to get rid of high concentration of ammonia nitrogen in wastewater. This way derives from combining the traditional amimonia stripping technology with ultrasonic, based on the traditional ammonia stripping treatment. In this experiment, the effects of pH value, initial ammonia nitrogen concentration, temperature and ultrasonic stripping time on the ammonia nitrogen removal efficiency were studied. The study indicated that under the condition of low initial ammonia nitrogen concentration, the ammonia nitrogen removal efficiency was not high. Under the condition of high initial ammonia nitrogen concentration, the ammonia nitrogen removal efficiency was much better than that of low concentration, the highest removal efficiency nearly arrived at 90%, i.e., with the increase of initial ammonia nitrogen concentration, the ammonia nitrogen removal efficiency was increased, and when pH value reached 11, the highest efficiency was achieved; When pH value was around 11, the ammonia nitrogen removal efficiency was increased with the rise of temperature and ultrasonic stripping time. At the same time, the optimized process conditions for ammonia nitrogen wastewater through the ultrasonic stripping are pH of 11, temperature of 30℃, stripping time of 80min.Under the optimized process conditions, a good treat result on the real ADC foaming agents wastewater was gained by ultrasonic stripping and under the condition of high initial ammonia nitrogen concentration, the ammonia nitrogen removal efficiency beyond 75%, even to 90%. In the second experimental phase, the A/DAT-IAT (Anoxic / Demand Aeration Tank-Intermittent Aeration Tank) technology was combined with the shortcut nitrification-denitrification technique to treat the ADC foaming agents wastewater. The experimental results indicated that it was possible to realize shortcut nitrification-denitrification biological nitrogen removal in A/DAT-IAT process by keeping the DO concentration at a low level (1.0mg/L) and a good treatment result on the ADC foaming agents wastewater was obtained. When A/DAT-IAT system ran properly and the average concentration of inlet ammonia nitrogen was 280.1mgNH₄⁺-N/L, the average concentration of outlet ammonia nitrogen was only 12.3mgNH₄⁺-N/L which means a nitrogen removal efficiency over 95%; It could realize shortcut nitrification in DAT when the DO concentration was low. It could restrain the growth of nitrite oxidize bacterium and keep the nitrite accumulation at a high level (the average nitrite accumulation ratio was 82.1%, even over 90%); There was no effect on the shortcut nitrification in DAT which had been formed under the condition of low DO, either by reducing the inlet ammonia nitrogen concentration or by increasing the DO concentration; There was no sludge bulking take place under the condition of low DO in A/DAT-IAT, and the SVI maintained at a proper level of 90～125mL/g which means a good sludge settleability.