...
In Fall 2013, we began laboratory testing. The team initially began by by preparing the lab area for hazardous chemicals with the proper personal protective equipment and appropriate signage. Then we went on to collect testing equipment such as the tube tumbler, test tubes, and the appropriate chemicals. We had to order tubes which had a filter insert so that we could test our small scale filtration process. There were also several chemicals which we needed to purchase to create our test groundwater. Once all of our materials were collected we were able to begin testing our process of sedimentation and filtration in a small scale reactor. Our GFAAS machine is not fully operational at the time; there are a few tubes which need repairing, but once this is complete, we are confident that we will be able to read concentrations of arsenic which are below five parts per billion.
Future Research
- Which coagulant, Fe(Cl)3, alum, or PACl is better at removing arsenic?
- Is arsenic removal limited by the mass transfer of arsenic to a precipitated coagulant surface, or by capture of the precipitated coagulant by plate settlers and filters?
- Would a floc blanket formed from coagulant precipitate enhance arsenic removal?
- Does addition of a small amount of clay enhance flocculation and arsenic removal?
- How can we reduce the amount of coagulant loss to the reactor walls? (contact chamber, clay)
- What is arsenic removal correlated with? What is the limiting factor?
- Due to the geometry of arsenic flocs, should we consider a coagulation-filtration system rather than attempting flocculation and sedimentation?
...