CLEAN WATER 4 ALL Revolutionizing the way you view dirt.

DIATOMACEOUS FILTER Our goal is to create a filter that… ….produces clean water fast. …removes dangerous parasites and bacteria. …lasts a long time. …costs next to nothing.

SINTERED FILTER DESIGN Good Water Bad Water (Pressurized) Pressurized Sintered System D.E. Maybe? ics.com/images/produ cts/filter_candles2.gif

Testing Pathway Slurry-based Resistance to resuspension Optimal thickness Sintered solid Geometric shapes Abrasion testing Mechanical testing Flow rate Bacterial Filtration Ability Production Cost Fouling Rate DEVELOPING OPTIMAL FILTER DESIGN Where we are

OLD GANTT CHART Clean Water 4 All Timeline Wk 5Wk 6Wk 7Wk 8Wk 9Wk 10Wk 11Wk 12Wk 13 3/12- 3/19 3/19- 3/26 3/26- 4/2 4/2- 4/9 4/9- 4/16 4/16- 4/23 4/23- 4/30 4/30- 5/7 5/7- 5/14 Pre-Design A1 - Establish Pure Slurry Baseline make thick filter cake and test A1 A2 - Sintering Process produce solid (bound) filter cakes determine optimal temperature A2 Product Design B1 - Flow modeling (Solid Works) B1 B2 - Mechanical Testing (3-Point Bending) B2 B3 - Filter Quality Testing microspheres as substitute filter bacteria B3 B4 - Abrasion Testing B4 B5 - Fouling Testing B5 Product Finalization C1 - Optimize to find final prototype C1 C2 - Determine materials & production costs C2 C3 - Make final presentation C3

REVISED GANTT CHART Clean Water 4 All Timeline Wk 5Wk 6Wk 7Wk 8Wk 9Wk 10Wk 11 Wk 12Wk 13 3/12- 3/19 3/19- 3/26 3/26- 4/2 4/2- 4/9 4/9- 4/16 4/16- 4/23 4/23- 4/30 4/30- 5/7 5/7- 5/14 Pre-Design A1 - Establish Pure Slurry Baseline make thick filter cake and test A1 A2 - Sintering Process produce solid (bound) filter cakes determine optimal temperature A2 Product Design B1 - Flow modeling (Solid Works) B1 B2 - Mechanical Testing (3-Point Bending) B3 - Filter Quality Testing: microspheres only B3 B4 - Abrasion Testing B4 B5 - Fouling Testing B5 Product Finalization C1 - Optimize to find final prototype and production process C1 C2 - Determine materials /production costs C2 C3 - Make final presentation C3

WHERE WE WERE LAST TIME…. Sintering – Signs of sintering not visible using SEM Pre-Sintering – Green Bodies Crack! Mechanical Tests- Initial 3 Point Bending shows increase in modulus with heating Initial Prototype – Built but needs modifications to stop leaks!

PRE-SINTERING PROCESS Styrofoam CupsFree Form

PRE-SINTERING Slower Drying Time (5 days+) + Plastic Slower Drying Time + Plastic Plastic Cups

PRE-SINTERING Plastic molds + Wax Less Cracks! Large surface bubble due to bubble on wax surface

SINTERING PROCESS 500 C for 2 hrs800 C for 6 hrs

SINTERING PROCESS 500 C for 2 hrs800 C for 6 hrs

INITIAL INSTRON TESTING Sample tensile bars tested directly after sintering Uneven surface topography (some bumps/ ridges from mold) and slight variation in thickness Sintering Temp [°C] Sintering Time Force at Failure [N] Flexural Modulus [MPa] 7002hr hr hr hr green

INSTRON TESTING: DECISION TO SAND Sanded sample top and bottom surface to make smooth and create uniform thickness Sintered Sample (600°C, 2hr) tested non-sanded and sanded yielded very different results Non-sanded Flexural Modulus: 20.7MPa Sanded Moduli: 120.9MPa, 183.3MPa

NON-SANDED SAMPLES Non-uniform slope- possibly due to non-uniform surface topography of samples

SANDED SAMPLES Smooth, sanded sample surface results in more linear slope

MECHANICAL TESTING DATA Sintering Temp [°C] Sintering Time Force at Failure [N] Flexural Modulus [MPa] 6002hr hr * 8006hr hr *’ 5002hr ’ 5001hr ’ *samples almost too short for testing; ‘samples exhibited uneven cracking surface Increasing sintering temperature and time exhibit overall trend of increasing flexural modulus

INTRINSIC PERMEABILITY ~Impervious ~Semi-pervious

PROTOTYPE Pressure Tester: PVC pipe unit Pressurized with Argon Easy sample removal Problems: Does not seal Sample breaks Too small z-direction: filters too thick

Silicone Solution? Last Time: Threads Leaked Sample edges leaked Sample was crushed Limited sample height Proposed Solution: Silicone Time and labor intensive Leaks Sample still crushed and height limited

THE NEW SEAL Aluminum Plates Silicone Seal PVC Pipe 3/8” Bolts Gasket

THE NEW SEAL, CONT. Leak Proof? Bolted plates allow huge compression for better seal Crack Proof? Sample seal independent of plate seal Scalable Design can be easily scaled

NEW HARDWARE, NEW HARDSHIPS Lateral Cracking Gasket? Maybe in 1 st run Flex of Al plate? ½” Back Plate ready to go Flow from edges Bad Silicone? Was in 2 nd run Silicone weak point? Try double sealing

DATA!

Flow Data Slow down Much slower flow rates on new samples Sinter time? Flaws in prior test? Different Slopes Could the steep slopes be crack slopes? 800 C sample was cracked at end of testing 700 C sample was cracked from the start

MOVING FORWARD Find innovative ways to reduced air bubble size Increase sinter time and temperature (new samples already baked 600 C for 26 hrs) to increase sample durability Test more flow rates and begin filter quality tests. Begin large scale economical analysis.

QUESTIONS?