The UV Intensity Setpoint Approach Re-defined: Using Validated Calculated Dose Algorithms to Develop Online Dose Monitoring Strategies That Do Not Require UVT Input
重新定义紫外线强度设定点方法:使用经过验证的计算剂量算法 开发不需要紫外线输入的在线剂量监测策略
During ultraviolet (UV) reactor validation, dose delivery, defined as Reduction Equivalent Dose (RED), is
typically quantified across different operating conditions of flow rate, UV transmittance (UVT), lamp output and in
some cases, lamp status. Empirical models (calculated dose algorithms) are then developed from
the validation data to express the measured RED as a function of the different operating
parameters. At installations, these algorithms are used to calculate the RED, given operating
conditions of each parameter. An alternative dose-monitoring strategy, known as the UV
intensity setpoint approach, can be defined by quantifying a UV reactor's RED as a function of
flow and lamp output. Per the German UV guidelines (DVGW) intensity setpoint approach, the
RED is confirmed at two test points with the reactor operating at a fixed flow and lamp output
(setpoint UV intensity); one at high UVT but with lamp power reduced till the UV intensity
matches the setpoint, and the other at maximum power but with UVT reduced until the UV
intensity matches the setpoint. In the field, a UV reactor is credited with the validated RED if the
measured flow does not exceed the validated flow and the measured UV intensity matches or
exceeds the setpoint UV intensity. In this paper, a new method is described whereby the
calculated dose approach was used to define an online dose-monitoring strategy that, like the UV
intensity setpoint approach, does not require UVT input. Includes figures.