2009 Task 3
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This team's task was to propose a way to remove particulates and several metals from brackish water as a pre-treatment step before, for example, the water was sent to a reverse osmosis process to make it suitable for drinking.  Their solution consisted parabolic solar trough to capture sunlight to boil the water followed by a condensation step.  This approach obviated the need for a follow on step altogether as the condensed water was immediately suitable for drinking.


Men in black, sort of.  Pat, Andy, Scott, and Jeff.  Taken just before they went in for the oral presentation before the judges.  That's why they're still smiling, their shirts are still tucked in, and their ties are not loosened.   Last-minute review of the talk and last-minute sweating before heading down (literally) to the judging chamber.
It's time.  Heading down to the presentation room.  This is the last known photo of these four gentlemen.
OK, enough fretting about the presentation.  Time to get going on setting up that bench-scale demonstration.   Construction of the parabolic trough begins.  The wood was cut in Athens and shipped to Las Cruces.  The straight planks were bought in Las Cruces.
The sheet metal is applied.  The reflective film will be applied to this.   Progress is being made.  Sheet metal attachment is almost complete.
Moving the trough outside for painting.  It was loaded onto the little gas cart WERC had available.   Application of a little Ohio University green to pretty it up.
After the painting, decals were added in Ohio University white, and then it was back inside to apply the reflective sheeting.   Outside now for the last step, adding the 8-foot pipe along the focus of the parabola.
Voila.  One parabolic trough, complete with reflective film and process fluid (water) pipe.  The little yellow things are thermocouples to monitor the temperature of the water inside the pipe during operation.  The vaporized water exits the pipe at the top end, where it passed through a condenser and was collected.   Scott demonstrates the addition of water to the pipe.  For the purposes of the bench-scale demonstration, the system was operated in batch mode, with water added from time to time as needed to replenish what was boiled away.  In practice, the process would be run continuously.
Looking down the length of the pipe from the top end, you can see the sunlight striking it.  The water temperature rose rapidly and reached boiling within about 40 minutes.  Fortunately for the universe, the members of this team had all just completed their heat transfer course prior to coming to New Mexico, so they all knew to a T how to calculate the heat transfer aspects of this system.  They predicted to within a nanominute how long it would take for the water to boil.  Actually, they were thrilled that it boiled at all, as we were unable to test this before going to New Mexico as there isn't the kind of sunlight in southeastern Ohio in February as there is in New Mexico in April.   The accompanying poster describing the concept the Task 3 team was demonstrating.
Prior to any visit by judges, a WERC camera crew came by, and the team members, hams that they all are, were more than happy to describe what they were up to.   Visit by a judging team.  Look at that clear New Mexico sky.  We had been concerned for months that the day we needed to do the demonstration would be cloudy, but we ended up with a perfect day.  Cloudless, and no wind, either.
The final step, collecting an actual sample for analysis.  That's Roseann Thompson, an official WERC person who has let us borrow her turkey cooker the last two years, doing the collecting.