Horizontal filtration is a completely new innovation for the AguaClara team, arising from a desire to make the 1 L/s plants easier to make and ship by eliminating the Enclosed Stacked Rapid Sand Filter. To create a horizontal filter, aspects of the sedimentation tanks and current filter design will be used, such as the relationship between backwash and operational speed, as well as the design of the plate settlers. Our goals for the semester are to begin design and fabrication of a horizontal flow filter. This will involve characterization of key parameters, using Fusion360 to make a model of the system, and fabrication of a prototype.
The goal of the Sensor Development subteam is to create sensors that help monitor water quality during the water treatment process, for the purpose of improving experimentation in other subteams and facilitating the work of plant operators. In particular, the team has been working on a particle concentration and turbidity sensor for the last few semesters, beginning with a fluidized bed solids detector developed for in-lab use and now a submersible solids detector for field use. The submersible solids detector is the main focus for the team this semester. Two different designs based on an endoscope and a pre-developed turbidity sensor will be tested to measure the height of the sludge blanket in the sedimentation tanks.
The AguaClara StaRS filter uses orifices with wings to inject water into and slotted pipes to extract water out of the sand bed. The system of orifices with wings was developed sometime in 2015-16 and has already been implemented in most (if not all) of the StaRS filters in Central America. The extraction system continues to rely on slotted pipes. The slots must be designed to be smaller than the smallest sand grains. The slots are 0.2 mm wide to safely handle the size distribution of sand that is 0.4 to 0.5 mm in diameter. We previously explored switching to a larger slot width, but although that may be possible it doesn’t solve the underlying problem that these slots will eventually clog and require cleaning. At Las Vegas, Santa Barbara, Honduras the slots are the site of calcium carbonate precipitation and require treatment with hydrochloric acid. Disassemble of a StaRS filter to clean the slots is labor intensive and thus our goal is to eliminate the use of slotted pipes.
The purpose of the StaRS FInE team is to design and develop an effective way to inject and extract water from the sand filter in the AguaClara Plants. The team currently combines methods of horizontal filtration along with fluid characteristics to determine an environmentally friendly and sustainable method of extraction.
The purpose of the Ram Pump team is to design and develop a properly functioning hydraulic ram pump, or hydram, for implementation in AguaClara plants. The hydram can be used to deliver water from below the facility back to the top for utilization in chemical stock tanks or to collect water at higher elevations for alternative uses.