More Pictures!

This is the final setup for our filters. Before moving it to this position, we would have to pour water straight into the filters. By doing so, it disturbs the top layer of sand, which is not good for the system. In our new setup, all we have to do is pour 1 liter of water into the beverage dispenser on the left and 2 liters of water into the beverage dispenser on the right (the amount of water is dependent upon the volume of each filter). We found the optimum outflow for each of the beverage dispensers, slow enough that they wouldn't overfill the filters, but fast enough that the water leaving the system would be a flow rate similar to a real bio-sand filter.

This is a top look into the larger filter where there is now a diffuser plate. It ensures that the water is disturbing the biolayer as little as possible. This piece is especially crucial for a real bio-sand filter where the user normally dumps water into the top of the filter. We've already controlled our system with the beverage dispensers, but replicating our system as close as possible to the real thing will hopefully give us results as similar to real-life application.

Side view of the diffuser plate on the larger filter. This one is held up by some string and rubber bands. As you can see, the top of the filter has a lip which would not easily allow something like the diffuser to end up where it is now. It has to be in this position because we will be adding our activated carbon filter piece to the top of this filter in a few short weeks. This diffuser placement was craftily done by Mikell who had to bend the diffuser plate before placing it into the filter and then unbend it once inside, no easy task. (Thanks Mikell!)


Diffuser plate on top of the smaller bio-sand filter.

This is the side view of the smaller diffuser plate. This one is held up by ridges at the top of the filter.

At the end of every day, we cover our system with black trash bags. We want the filters to be in as little contact with sunlight, which could potentially stimulate some unwanted growth.


Thanks for reading =)

Pictures!

Click on the picture to see it larger:

C

-This is what the granular activated carbon (GAC) looks like!

-GAC and "teabag" approach (will explain later)

-Up-close look at the different layers in a common sand filter. From bottom to top, it's large gravel, smaller gravel, little pebbles, big sand, and filter sand the rest of the way up.

-Wire mesh to keep gravel from clogging the drain in the smaller sand filter.

-This is the smaller sand filter, with the wire mesh shown.

-Here's our setup in the lab!

-Look how dirty that water is!

-You wanna drink that?

-Will it come out clean?

-I'd drink that...Ok...maybe not...but it's a good start!

-Remember when I talked about drilling the holes? Here's the tool we used. A drill bit taped onto a long stick. Fact: The greatest inventions in the world involve duct tape.

-Here's how it was done...very slowly...

-Up close view.

-Pretty bored at this point...(10 minutes to drill 1 hole)

-Ami, you try. Much more enthusiastic!

-These are different sieves. You can see the different size holes that we use to pick out the exact type of sand we want. Basically, you put a mixture of dirt/gravel/sand into the top and shake it for awhile. The different size particles will land on the different layers so you know their average diameter.

-These are sieve shakers. They provide the shaking power needed to separate the sand on the different layers!

-Washing the sand before we use it as filter sand. It's pretty dirty. If you don't wash it, then it doesn't filter the water as well, it's all full of nasty stuff already and won't take any of the nasty stuff out of the water.

-This is a lot better, and about what it should look like. If the sand is too clean the water will go through the filter too quickly and won't filter as well. There's a fine line between being TOO dirty and being TOO clean. It takes practice! (We got a lot of it)


Hope these were fun to look through! We'll have more later.


Mikell

Getting our sand ready & more!

Over the past week, Ami and I have been preparing the sand for our models of the biosand filters (BSF) we're going to make. We wanted to make it as close as we could to what is found in Nicaragua so we ran a sieve analysis to get the correct size & gradation of the sand. We also washed the sand and have been drying it in the sun all week.

To reduce costs, we are trying to use the materials available in the environmental lab here at Santa Clara University. We had planned on using two glass columns (glass is inert and won't react with anything in the water) that we found in the lab. Turns out, they were designed to be used for something completely different than what we were trying to do. I believe they are for chemical purposes because there was a ceramic layer in the column that would not even allow water to go through! The pore sizes must be rather small. We got the OK from our adviser to go ahead and drill through the ceramic part of the glass column so that we can use it for our purposes. I'll throw up some pictures tomorrow when we drill to show you exactly what I'm talking about. It's hard to explain! 

Mikell

Update

Hi everyone,

Time for an update! It's been a busy past week and a half, but a lot has happened. Ami and I will be making our pilot testing systems this week. We have received information on how the filters are made in Nicaragua, and we are going to mimic them to the best of our ability. Also, we are trying to raise money to fund our trip to Nicaragua! I'll be talking about that as well in a bit.

Project: 

So, I'm going to try and explain this in non-engineering jargon so everyone can understand it. We've run into a little bit of a problem in the past week or so...in our original idea, we would filter water with chlorine first, then through activated carbon, and then through the biosand filter (BSF). However, we began to worry about whether or not the BSF would function properly if the water was "too pure" after going through chlorine and activated carbon first. It's easy to understand if you think about it, BSFs work by developing a biological system inside. Over time, with dirty water going through the filter, "good bacteria" begin to form inside the filter. These bacteria are what destroy all the "bad stuff" in the water. When water is chlorinated and run through activated carbon prior to the BSF, what does the biological system have to eat to stay alive? That is the problem we are working on right now.

We have decided to test 3 different systems:

1. For those who don't have a BSF, we will see what the water looks like after just being chlorinated and run through the activated carbon.

2. For those who DO have a BSF, we will try the original setup: Chlorine, Activated Carbon, then BSF. We will test whether or not the biological system inside the filter can still develop under these conditions.

3. The other setup with those who DO have a BSF: BSF, Chlorine, then Activated Carbon. This way we know the BSF will function properly. The only downside to this is the hassle. A user has to do a three step process, and in Nicaragua, they are more likely to skip some of the steps if it requires too much effort.

We will test the effluent and all these and weigh the benefits and costs of each system.

Fundraising:

Our total project costs approximately $5000. This includes material costs here in Santa Clara for testing purposes, travel to and lodging in Nicaragua, and administrative support for our nonprofit, blueEnergy. We have already received a grant from the School of Engineering here at Santa Clara University for $3500 (no easy task; if I can toot my own horn!), and we are trying to raise the extra $1500. Anything left over we will end up covering ourselves.

When working on projects in the third world, it is imperative to visit the project site to truly understand everything that's going on. Of course we can hear testimonials of those who have been there, but without truly immersing ourselves in their problems and roadblocks (not to mention their wonderful culture), we will never be able to develop a system for these people that will work well in the area, and that they will accept into their daily lives.

We are working with a website that partners with nonprofit organizations to raise money. Money that we raise for blueEnergy through the website will go directly to the cost of staying in Nicaragua with them. blueEnergy has been supporting us with information over the past few months and will provide us with food, safe lodging, and on-site logistical support once in Nicaragua. They are a nonprofit that is definitely worth supporting, but you don't have to think about it like that! Think about how you'll be helping us go on an experience of a lifetime. A trip like this can change our lives! Our fund-raising website is: http://cocofiltro.blogspot.com/. I've also attached a widget on the post below where you can track our progress! I'm new to this blog stuff so that was pretty cool for me!

Please feel free to ask us any questions about the project, the fund-raising... anything! We are excited and we hope to get you excited as well.

Thanks for reading!


Mikell & Ami

Help us get to Nicaragua!

Hi everyone! Here's the link to our fund-raising page!



You can also do "offline" donations if you would rather not use the website. I will update the number!

Mikell