紫外消毒数值模拟及生物验证

Numerical simulation of UV disinfection and bioassay validation

摘要:

为建立紫外消毒系统优化方法,基于光强分布、流场分布、当量剂量求解,开展紫外消毒的数值模拟,针对腔体式紫外消毒反应器,在80％～95％透光率和240～600 L／h流量条件下对模型进行生物验证．结果表明:该模型能够较准确地预测消毒效果,当量剂量模拟结果与实验结果在不同条件下相差3％～12％．有效剂量随处理流量的增加而降低;消毒效率随溶液透光率的减小而降低,但是随着流量的增加,透光率影响降低,高流量(600 L／h)下,透光率对消毒效率影响小于3％．流场的可视化为设计优化工作提供了分析依据,反应器内前段,反应器内壁处光强小而流速大,是影响消毒效率的原因．数值模型为系统优化设计和剂量同步提供了依据．

Abstract:

To establish an optimization method for UV systems, numerical models were developed based on UV intensity field, flow field and equivalent reduction dose (RED). The model was verified using bioassay on the condition of the UVT (80％-95％) and the flow rate (240-600 L／h) with an annular UV reactor. Results showed that the model predicted the disinfection efficiencies with good accuracy. RED from simulations and experiments under different conditions had a difference of 3％-12％. RED increased with the increase of flow rate and decrease of the transmittance. However, transmittance had merely a slight impact, about 3％ on RED of high flow (600 L／h). Visualization images showed that near the inlet of the reactor, the UV intensity was weak while the velocity was large adjacent to the wall, which had a negative effect on disinfection efficiency. This numerical model provided a basis for UV system optimization and dose synchronization.