Huang Y, Li Y, Pan Y
Department of Environmental Science and Engineering, University of Science and Technology of Suzhou, New District, Suzhou 215011, China.
Water Sci Technol. 2004;50(6):179-88.
An updated biological nitrogen and phosphorus removal process--BICT (Bi-Cyclic Two-Phase) biological process--is proposed and investigated. It is aimed to provide a process configuration and operation mode that has facility and good potential for optimizing operation conditions, especially for enhancing the stability and reliability of the biological nutrient removal process. The proposed system consists of an attached-growth reactor for growing autotrophic nitrifying bacteria, a set of suspended-growth sequencing batch reactors for growing heterotrophic organisms, an anaerobic biological selector and a clarifier. In this paper, the fundamental concept and operation principles of BICT process are described, and the overall performances, major operation parameters and the factors influencing COD, nitrogen and phosphorus removal in the process are also discussed based on the results of extensive laboratory experiments. According to the experimental results with municipal sewage and synthetic wastewater, the process has strong and stable capability for COD removal. Under well controlled conditions, the removal rate of TN can reach over 80% and TP over 90% respectively, and the effluent concentrations of TN and TP can be controlled below 15 mg/L and 1.0 mg/L respectively for municipal wastewater. The improved phosphorus removal has been reached at short SRT, and the recycling flow rate of supernatant between the main reactors and attached-growth reactor is one of the key factors controlling the effect of nitrogen removal.
提出并研究了一种改进的生物脱氮除磷工艺——BICT（双循环两相）生物工艺。其目的是提供一种工艺配置和运行模式，该模式便于优化运行条件，尤其有利于提高生物营养物去除工艺的稳定性和可靠性。所提出的系统由一个用于自养硝化细菌生长的附着生长反应器、一组用于异养生物生长的悬浮生长序批式反应器、一个厌氧生物选择器和一个澄清池组成。本文描述了BICT工艺的基本概念和运行原理，并基于大量实验室实验结果，讨论了该工艺的整体性能、主要运行参数以及影响COD、氮和磷去除的因素。根据城市污水和合成废水的实验结果，该工艺具有较强且稳定的COD去除能力。在良好控制的条件下，TN去除率可分别达到80%以上，TP去除率可达到90%以上，对于城市污水，TN和TP的出水浓度可分别控制在15mg/L和1.0mg/L以下。在短污泥龄时实现了强化除磷，主反应器和附着生长反应器之间上清液的回流流量是控制脱氮效果的关键因素之一。
