Zeyu Yao's Individual Contribution Page

Fall '13 Contributions

Mid-semester contributions

Chlorinator packaging for India

I prepared a setup manual for local personnel who are not familiar with chemical dose controller to aid the system assembling process. I also started to prepare a packaging spreadsheet because a large of the components need to be pre-assembled in lab since they cannot be locally sourced as well as easily assembled. This spreadsheet will be complete once Mathcad codes are embedded. 

Improving CDC design

I calculated using Mathcad the number and length of dosing tube for a low flow plant (plant flow rate = 2.4 L/s), and modified the manifold design based on the calculations. Changes I made to the setup include cutting the manifold to only two pairs, and eliminating or shortening unnecessary tubings and pipes. I also tested drop tube calibration and found that a ball valve can be attached so solution volume can be directly measured in drop tube. The added weight of ball valve may offset the balance of lever arm, but errors are negligible.

I did research on different types of constant head tank to replace the one that is not chlorine resistant. I found a Nalgene bottle and cap made of chlorine resistant materials, and also a chlorine resistant bottle with a regular cap with Teflon cap liner added. 

I designed a single lever for dosing one chemical, and made Sketchup drawings for the lever arm and drop tube group.I have been working until now on the chlorinators package for low flow rate plants in India. My contributions to the design of the half size single lever system include the calculation of dosing tube number and length, cutting the manifold leading to solving the air bubble problem, measurement of change in water level in CHT as a function of flow rate, and the research of materials to replace non chlorine resistant parts. I also decided to write an "Ikea-style" set up manual for the chlorinators packages shipped to India on October 4th. The manual contains clearly labeled pictures of the components so it can be used by someone with minimal knowledge of the parts of the system. I am currently working on calibration of the CDC using the drop tube, and the incorporation of calibration marks into future drop tube design.