Objective & Motivation
Flocculation is an important process to water treatment.
Semester Research Goals
The team has discussed and agreed on several important goals to focus on for the Spring semester 2008:
1. Analyze the data from the Fall Semester 2007 and make solid conclusions. The team will look into further analytical tools such as Excel, MatLab, and MathCAD to handle and display the data in a better, more user friendly format. The team last semester found that the current MathCAD file is hard to use, for example if the user wants to isolate one run in a series of iterated experiments or compare certain runs to each other on the same graph.
2. Develop models to describe what is happening in the flocculator. The team will use this to determine what parameters are important in regulating the flocculation process.
3. Literature research to compare research, to see if previous similar experiments have been conducted, or for inspiration for further experiments or data analysis.
4. Find the relationship between G and G¿. This is the ultimate goal that the team is trying to determine, it will take a combination of data analyses, modeling, and maybe more experimentation.
Past Research
The Lab Flocculator research team has an important focus on investigating the relationship between fluid shear (G) and its effect on overall flocculator mixing (G¿). Floc formation and breakup rates depend greatly on the G¿ parameter, which is intrinsically related to the fluid shear present inside a reactor. The semester research goals of the Lab Flocculator research team was to measure the relationship between G and G¿ by performing experiments using a coiled-tube flocculator experimental apparatus. The team decided to first perform experiments to determine the appropriate alum dose to achieve optimal floc formation for the experimental apparatus. Experimental data showed that a 25 mg/L concentration of alum produced the best results for a range of influent turbidity between 50-150 NTU and a humic acid concentration of 35 mg/L with minimal marginal improvements thereafter; thus, subsequent experiments were conducted with a constant 25 mg/L alum dose. Throughout the semester, the team was faced with numerous obstacles originating from the physical apparatus and the various software used by the team. Sedimentation of clay inside feed tubing and the flocculator inhibited various experimental controls including influent turbidity, flow rates, and also data collection. Measures were taken to overcome this issue, but sedimentation should ideally only occur in the settling column during the appropriate operational state. The flocculator team has overcome a large learning curve of needing to understand the experimental setup, Process Controller, and the MathCAD data processor tools. Much data was collected of different combinations of important variables such as flow rate, influent turbidity, and flocculator length. Currently, only a qualitative analysis of the data has been performed and the team is satisfied with the data set obtained. During coming semester, the team will focus on developing an analytical model to better analyze the data as well as to present it in intelligible figures and charts in preparation for publication.