Engineering 692, Montana de Luz, 2011: The Biodigester Team

Nathan Arroyo, Nicolas Campos, Melissa Lindsey, Sarah Watzman

I. Background

Montana de Luz, an orphanage in Honduras for children with HIV/AIDS, currently has a malfunctioning biodigester installed. A biodigester operates by digesting organic waste and turning it into methane gas, which can then be burned to use to power the orphanage’s appliances.  The gases are formed from the breakdown of the organic waste (called influent) in the air-tight dome section of the biodigester. The output of the biodigester, called effluent, is nutrient-rich and extremely useful in farming or gardening.

More specifically, Montana de Luz has a fixed-dome biodigester. The influent is poured into a pipe, travelling into the ground to the main chamber. The top of the main chamber is at ground-level, and an air-tight door exists there to be used if looking inside the chamber becomes necessary. The gas pipe comes from the top of the dome as well, and it travels to the kitchen next to the chicken coop. The effluent comes out of the biodigester through a pipe above ground.

II. Participants

Nathan Arroyo is a fourth-year student in environmental engineering and has functioned as the team’s contact with Montana de Luz and Dr. Jay Martin. In-country, he updated the preliminary manuals created before departure and added necessary details to the manuals once back in the United States.

Nicolas Campos is a fifth-year student in mechanical engineering and has functioned as a translator from Spanish to English for the documentation provided before departure regarding Montana de Luz’s biodigester. He also was the main photographer for the project while in Honduras and translated manuals written by the team from English to Spanish.

Melissa Lindsey is a first-year pre-biomedical engineering student and has functioned as the team’s secretary. In country, her task was to keep detailed notes of progress made and data collected, and compiled these notes into the team’s final presentation.

Sarah Watzman is second-year mechanical engineering student and has compiled the information gathered by the team before, during, and after the trip into the final report. She served as the videographer while in Honduras.

III. Problem Definition

Montana de Luz currently has a fixed dome biodigester installed on its campus. Some documentation is available, but whether or not this documentation is for biodigesters in general or this specific one is unclear. Additionally, no documentation on how to properly operate or fix this biodigester exists.

Currently, the biodigester on site is not functioning properly. Originally, while discussing operations of biodigesters and potential problems causing them to malfunction, Dr. Martin suggested that the dome of Montana de Luz’s biodigester may be cracked. This would cause the gas produced through the anaerobic reactions in the chamber of the biodigester to leak out into the atmosphere instead of flowing into the gas pipe for use by the orphanage’s staff. Through email communication with the staff in Honduras, a crack in the dome was deduced as not the cause of malfunctioning since Saul was able to light a lamp powered by the gas pipe.

From pictures taken of the system last spring, the team has concluded that the influent is not acceptable for the biodigester to be operational – it appears to have too high of a ratio of solids to liquid. This has most likely caused the biodigester to be clogged in both the inflow and outflow pipes, stopping effluent from leaving the biodigester and inhibiting influent from entering it.

IV. Statement of Objectives

In general, the objective for this project is to get the biodigester at Montana de Luz into a functioning state. Mainly, this includes unclogging the inflow and outflow

pipes. Once the pipes are cleaned, an inoculate (such manure) will be added to the main chamber to help restart the anaerobic digestion within the biodigester. Adding an inoculate will also help digest the already present materials within the main chamber in a more time-efficient manner.

Additionally, a secondary objective for this project is to define the operational parameters for the biodigester explicitly and in easy-to-use terms. This includes developing step-by-step instructions for diagnosing potential future problems for the biodigester and instructions for trouble-shooting these problems as well. These manuals will be written preliminarily before departure to Honduras and updated to coincide with observations made while at Montana de Luz. These manuals would serve to ensure that the staff at Montana de Luz knows how to properly operate the biodigester, and also make suggestions for fixing it in the future if it beings malfunctioning again. Along with these written manuals, pictorial posters will be made to hang in the administration office on site.

More specifically, under the scope of the manuals, a system for inputting the proper ratio of water to solid in the inflow tube will be developed. This will most likely consist of filling a bucket a certain number of times with water and mixing it with one bucketful of solid to be put in the biodigester as influent. In order to decrease the size of the solid pieces used as influent, a compost area near the biodigester will be developed, and suggestions for stirring it will be included in the manuals.

V. Detailed Plan of Action

1. Evacuate gases from chamber

a. Includes opening the gas pipe and cover to main chamber

2. Clean debris from biodigester

a. Includes cleaning the influent pipe, effluent pipe, and main chamber as well as the area surrounding the biodigester

b. Would be best to move as much debris from the main chamber as possible

3. Fill the biodigester with water

a. Check and record chlorine levels of water before placing in biodigester

b. Let water sit in biodigester until chlorine level is 1 part per million (ppm), 10 ppm at 3 days later then wait, 5 ppm at 2 days after that then wait, then below 5 ppm for a day

c. Record amount of water poured into biodigester

d. Leave chamber cover open

4. Obtain initial charge of biomass

a. Initial charge should be cow manure but chicken manure and other biomass will substitute fine

5. Charge biodigester

a. Test water again for chlorine levels

b. If water is below 1 ppm chlorine, charge biodigester with 8-10% of weight biomass to water

6. Stir contents of biodigester with a stick

7. Create compost pit in a convenient location near biodigester

8. Mark buckets for use

a. Using geometric shape of bucket, devise system to input influent with a ratio of 8-10% biomass from compost to water

b. Average density of compost is 2000 lbs/cm^3

9. Post signs about usage

a. Use appropriate materials to create signs

b. Create sign for proper loading

c. Create sign for no smoking or open flame near biodigester

d. Create sign for feather test at gas outlet

10. Conduct pH test on effluent

a. pH is optimal between 7.0 and 8.5

b. If pH is higher than 8.5, biodigester needs to be cleaned and restarted

11. Let biodigester sit for 2 weeks to allow bacterial growth inside the chamber and to allow the compost pile to grow

12. Train staff on usage through a training session including safety precautions

13. Create manual for continued operation

a. Includes operational and start-up procedures

b. Includes safety procedures

VI. Implementation

Monday, March 21st, 2011

o The biodigester had been cleaned previous to arrival. The inflow area was no longer clogged and liquid, instead of solid, was sitting in the outflow tube.

o In order to get effluent from the biodigester to test the pH, water was added. After adding 2.5 buckets of water, effluent starting coming out of the outflow tube.

o The effluent was tested with water test strips, and the pH was determined to be 8.5, which is too basic for a biodigester to run properly. A hose was put inside the inflow tube to run water into the biodigester to help neutralize the pH (ideal pH would be 7, and Montana de Luz’s water is cholorinated, making it slightly acidic). Since the orphanage lost electricity after lunch and water needed to be conserved, the hose was turned off mid-afternoon.

o Since the compost pile sitting on the ground near the biodigester contained lots of trash, the pile was turned and moved towards the pig pens while the trash was removed.

o The gases were evacuated from the gas lines by opening the valve connected to them for the stove next to the chicken coops. Using a lighter, no gas caught on fire so the pipes were concluded to be empty.

o Brainstorming took place to get ideas for removing effluent from the biodigester. A bucket with a rope on it was the simplest idea, but Saul suggested creating a system for distributing the effluent to the garden,

which included some sort of tank or crate with a valve on top of a wheelbarrow.

o Brainstorming also took place to get ideas for composting. Alexandra suggesting using one of the pigpens since they are next to the biodigester and a contained area.

o The pH was tested at the end of the day and was slightly lower than in the morning, at about 8.3.

o A long metal rod was pushed down into the chamber of the biodigester through the outflow tube – the biodigester’s contents felt like wet sand.

Tuesday

o With Saul’s help, a three-stage compost system was implemented in pigpen next to the fence by the biodigester.

o Two walls were built out of cement blocks and mortar, with the back wall being offset from the front wall.

o The first section closest to the door is for fresh waste to be put in the compost pile, the second section is for older compost not completely broken down, and the third section is for compost ready to use. The third section is over the drain in the back corner of the pigpen.

o The finished compost will be used as influent (mixed with water) for the biodigester since it will be in small particles, not large chunks.

o In the afternoon, the team began surveying for the map of Montana de Luz. See the addenda for details on this subproject.

Wednesday

o The compost sitting in the open area near the biodigester was moved into its new home. The barrel of compost (which had been sitting for over a year) was turned over and moved into the new compost area as well.

o The biodigester was determined to have already digested solid in it, meaning that it needed to be completely flushed and emptied.

Using the long metal rod, solids were found to be sitting about one meter down the inflow pipe.

Since the consistency of the material in the chamber was found to be slushy, the water which had been put into it had most likely just been flowing over the top, like water over wet sand.

In order to lower the pH to a usable level, the water would need to mix with the slush inside, which was not happening since only liquid was coming out as effluent.

o Suggestions were made on how to empty the biodigester:

Saul said the cement cap could be removed and replaced after the solids were pulled out of the main chamber, but this would involve pulling the solids from the depths of the main chamber, which would be extremely difficult.

Renting a pump in Honduras would cost about 17,000 Lempira, or roughly $1,000, which was not within our budget.

The final decision was made to buy a septic pump in the United States and send it down to Montana de Luz with Ruth at the end of April, 2011. Saul could then use it to empty the biodigester as well as for the orphanage’s own septic tank.

o The following details were found during research in the computer lab.

Compost needs to be turned about every 14 days to break up clumps and rotate the middle sections to the edges and vice versa.

Compost needs to be aerated and thus should sit in an open area, not closed in a barrel.

Compost needs to stay damp – not dripping with water but not dry either.

Different types of waste break down at different paces so food remains should be mixed with plant materials.

Bones and meat should not be composted.

When ready to use, compost should look like soil.

o Outlines of the posters were made with Ruth’s help in translating. A poster was designed for each of the ideas below:

How much and how often to add water and organic materials to the biodigester

What to put in the biodigester and what not to put in it

How to turn the compost and how often, along with how much water to add

How to recognize when the compost is ready to be used as influent for the biodigester

o A system for mixing the correct ratio of water to composted material was developed: Fill half of a bucket with compost and pour into the cemented inflow area. Then fill the inflow area with water until the line on the tube is covered. Mix the compost with the water then remove the tube to drain the mixture into the biodigester.

o The door to the compost area was fixed to close completely since it did not previously. The drain in the ground for the final stage of the compost was covered with wire gauze since it was originally uncovered.

Thursday

o In the morning, the compost in the new compost area was mixed, turned, and watered. The drier compost which had been sitting out in the open was put in the first section while the barrel of compost was put in the second section on Wednesday. These piles were mixed and watered so that they were damp, and then the compost was split between the two sections.

o Since water had been flushed into the biodigester earlier in the week, effluent liquid was removed from the outflow area using buckets on a string. Effluent was removed until no liquid was above the opening of the outflow tube.

o After lunch, Karin checked the Spanish translations of directions for the posters to be placed by the compost area and the biodigester. The posters were written/drawn and then covered in laminate sheets.

Friday

o Friday morning consisted of working on the surveying project, details of which can be found in the addenda.

o Friday afternoon consisted of presentations from the group to Alexandra, Karin, and Saul with Brad, stating what had been accomplished throughout the week, what needed to still be accomplished by Montana de Luz staff to maintain the project, and suggestions for the future.

VII. Results and Objectives Achieved

The compost system was successfully established inside the pigpen for three-stage composting. The orphanage can now place food waste (except meat and animal bones) in the first stage and once the process is finished, can use the compost as influent for the biodigester. Three posters were made and placed next to the compost area detailing what to put in the pile to compost, how to compost (including when to water and turn the piles), and how to know when the compost is finished.

Although the biodigester was not left in a working condition, prevalent information was obtained from the trip. The chamber of the biodigester was determined to contain already digested materials that were not flowing out of it due to a previous charge with too high of a ratio of solid to liquid. This conclusion was drawn from the pH of the effluent being too basic (around 8.5, suggesting that too much carbon from organic solids was inside the main chamber), the fact that mostly liquid was flowing out the outflow tube, the texture of the biomass inside the main chamber being slushy, and no gas coming out of the gas pipe in the kitchen during the flame test (indicating that the contents of the main chamber could not be further digested to produce more gases). To return the biodigester to a working condition, the team determined that sending a pump to Montana de Luz from the United States was the best decision, so that Saul could pump the solids out of the main chamber and begin the process with a clean slate.

Nevertheless, operational parameters were established and detailed in a poster hung next to the biodigester. Half a bucket of prepared compost is to be put into the concrete inflow area, then the area is to be filled with water to the line marked by the team on the pipe. This is to be mixed and then drained into the biodigester by removing the part of the pipe coming out of the concrete inflow area.

Also, an effluent transport system (ETS) was created to make distributing the effluent from the biodigester to the garden easier. A cooler was attached to the top of a wheelbarrow so that it could be easily moved from one location to another, and a small hose was attached to the drain valve of the cooler. When effluent liquid is placed inside the cooler and the valve is opened, the hose can be used to distribute the effluent to plants in the garden as fertilizer.

The results from the surveying project are summarized in the addenda.

VIII. Future Recommendations

Once the biodigester is in a functional condition, it could potentially produce more gas than needed to power the stove in the kitchen next to the chicken coop. A suggestion for a future project once this state is reached would be to run more gas lines from the biodigester to other places needing gas as fuel at Montana de Luz.

Another future recommendation would be combing different systems at Montana de Luz that are currently independent of one another, such as the tilapia pond, the biodigester, and the garden. Since the tilapia pond may need to be drained or have water removed occasionally, that water could be mixed with compost to put into the biodigester or used to water the garden. Additionally, any algae or other plant life supporting the tilapia pond that may need to be removed could be added to the biodigester as organic material. Effluent from the biodigester, if not used as fertilizer in the garden, could also potentially be put into the tilapia pond in small amounts to help fuel that ecosystem. Any system devised to combine currently independent projects to make Montana de Luz more interdependent could be beneficial.

From the surveying project, a major future recommendation would be for a team to find a back-up power source for the water pump. Having running water is extremely crucial to any community, especially one supporting a large amount of children. Therefore, finding a system to allow the orphanage to obtain water even when the power is out would be extremely beneficial to Montana de Luz. Potential back-up system ideas include a generator for the water pump, connecting a solar panel to the water pump with a battery to store solar power to be used when the electricity does not work, or installing a manual pump for the water well.

IX. Addenda

a. Team Biodigester Agreement

b. Email Communication with Montana de Luz Staff

c. Email Communication with Dr. Jay Martin

d. Budget

e. Work Schedule

f. Manuals for Montana de Luz Staff

g. Surveying Project

h. References

Team Biodigester Agreement

Team Members

Nathan Arroyo.7 (912) 258-3818

Nicolas Campos.19 (513) 373-2510

Melissa Lindsey.193 (614) 378-8846

Sarah Watzman.4 (513) 240-0640

Team Project Expectations

The purpose of our project is to provide troubleshooting methods and implement a solution to the malfunctioning biodigester in Montana de Luz. Also, we plan to implement a filtration system for the influent and a storage and delivery system for the effluent. This will be documented in order for the residents to maintain the biodigester and for future Ohio State groups.

Team Member Roles and Responsibilities

Secretarial Responsibilities and in-country recorder - Melissa Lindsey

Translation and in-country photographer - Nicolas Campos

Project Documentation “Compiler” and in-country videographer - Sarah Watzman

Communications manager and in-country manual updater - Nathan Arroyo

Team Meeting Ground Rules

Decisions should be made collaboratively

Attend all meetings/ classes

Be respectful to other group members opinions

Share workload evenly

Take responsibility for your part

Stay on topic

Be prepared and ready to work

A consensus should be made on major decisions

Use class as team meeting time, do individual work outside

Effective communication (reply all emails)

Team Member Signatures

Nathan Arroyo _________________________________

Nicolas Campos _________________________________

Melissa Lindsey _________________________________

Sarah Watzman _________________________________

Date Signed 2/2/11

Email Communication with Montana de Luz Staff

Alexandra,

    Hello!  I have been assigned to be the contact between MDL and the biodigester team here in Columbus and imagine you will be receiving frequent emails from me in the next 2 months as we prepare for our trip to Honduras.  I am writing today in regards to the initial questions and concerns that we have fostered about the biodigester at MDL.  The first questions we would like to know is what does MDL want and expect out of the bio-digester in terms of function and use?  Also how would MDL like it to be utilized so that we have a better understanding of how we can help approach and solve these issues in a helpful way.  Second, we would like to know what does Saul or any other staff member know about the biodigester?  This would include any information about intallation, dimensions, current state, contents, and modifications or attemps to run since being installed.  We look forward to working with you to make the biodigester operational and useful the MDL. 

Thanks,

      Nathan Arroyo

Dear Nathan- When I was in Honduras in January I met with Saul and he indicated to me that he believes the biodigester works as he used a lightbulb to test it. He said it needs serviced but beleives it works. I will let Alexandra respond regarding any other details since she is more informed than I am! It would be great if we could get it working on a regular basis to help us provide power!

Erika

Erika,

 

Thanks for the information.  Would you happen to know if what Saul lit was an actual light bulb or a gas lamp?  

 

Alexandra,

 

We look forward to hearing from you.  We have come up with a large number of questions concerning the state and condition of the biodigester that will help us create an appropriate plan to make it operational.  We realize that you have a busy a schedule and hope you will have time to reply soon.  Your answers will allow our trip to Honduras to be a success for both MDL and our team.

 

Thanks,

     Nathan Arroyo 

Hello Nathan,

We apologize for the delay. Between a lack of electricity and getting ready to send the kids back to school, we have had a lot going on. However, Karin has met with Saul, who has the most information about the biodigester and she will be getting back to you all as soon as she can.

Thanks, we look forward to working with you.Alexandra and Karin

Hello Nathan, I apologize for the delay.  I'll answer your questions now:

The first question we would like to know is what does MDL want and expect out of the bio-digester in terms of function and use?We expect to use the digester to generate methane gas, fertilizer for

vegetables, fruit trees and plants in MDL. All this would be through the utilization of waste coming out of the kitchen.  Also how would MDL like it to be utilized so that we have a better understanding of how we can help approach and solve these issues in a helpful way.  Training for better control and management of the digesterSecond, we would like to know what does Saul or any other staff member know about the biodigester?From the MDL's staff, Saul is the only person who has worked with a biodegister, but he knows all about it.  This would include any information about:

 intallation, dimensions: I have attached the design and dimensions of the digester. 

 current state: out of use

contents: The digester is made with brick, pvc pipe, cement, and sealant...

and modifications or attemps to run since being installed: Since installing the digester, there has been no modification.  The digester was used only once (during its initial test run.)  Saul commented that the digester has not been used for three years, but he believes it works.  One of the reasons that the digester has not been used is because MDL now does not generate enough waste to fill the capacity of the digester.

   Feel free to contact me for any questions.

Thanks, we look forward to working with you. 

--

Karin Timpel

Karin,

 

Thanks for your help.  We will be having a class meeting tonight and coming up with more questions to help us move forward.  We will be sure to get them out to you as soon as possible, either tonight or tomorrow.

 

Nathan

Karin,

 

The following is a list of the questions for the biodigester we came up with after tonights meeting:

 

1.  Does anyone at MDL know who installed the biodigester and if so do you have any contact information for the company?

 

2.  Are there currently anything contents inside the biodigester like food scraps or water?  We saw a couple of pictures from the trip last year and it appeared that the input and output pipes were stuffed full and clogged.

 

3. If the pipes are clogged, can the MDL staff unclog them before we arrive?  This isnt absolutely necassary, but it would greatly help the process and time line of getting the biodigester up and running.

 

4. If the pipes are unclogged or the MDL staff can unclog them, would it be possible for someone from the MDL staff to fill the biodigester with water and keep it filled until arrive?

 

5. Can MDL obtain or currently have a scale we could use for measurements?  This is not necassary either, we can bring a scale with us if necassary.

 

6. Can MDL obtain or currently have 2 or 3 five gallon (or liter equivalent) buckets that can be used soley for the the biodigester.

 

7.  Does MDL currently have a manual meat grinder to grind most kitchen waste that would be used in the biodigester or can MDL find one for purchase in Honduras and get back to us and compare prices between Honduras and the U.S.?  This maynot be needed for operations but would be nice to know in case it is.

 

8.  If MDL is not able to unclog the input/output pipes of the biodigester, if they are actually still clogged, does MDL have tools or other things that would allow us to unclog it upon arrival?  Possibly a shovel and some sort of pole with a hook or a point on the end of it to drag things out of the pipes.

 

9. Is there a specific person at MDL that is going to be in charge of the biodigester that we will have a chance to train while we are there?

 

10. Is there a container or place to store the daily kitchen waste from MDL?

 

11. Is MDL composting at all?

 

12. What does MDL do with the chicken manure it generates?

 

13. How does MDL currently irrigate its crops?

 

14.  Does MDL know of any cattle farms in the area that we might be able to obtain some manure to initiate the biological activity in the biodigester?

 

15.  Do  you have a sample list of the normal types and amounts of kitchen waste MDL produces?

 

We know that this is a long list, but we would appreciate any answers and help you can give us.

 

Thanks,

Nathan and the biodigester team

No response was received from this email.

Email Communication with Dr. Jay Martin

Dr. Martin,

 

    Since the lecture you gave in class a couple of Wednesdays ago, we have decided to undertake the task of making the biodigester at Montana De Luz functional.  In this process, we have come up with a few questions we are wondering if you could help us solve.  The most pressing questions we have are what is the ratio of organic matter to liquid put in a biodigester, and how often does the bigester need to be fed?  We have other questions but rather than flood you with them, we would like to know if you woud be willing to meet with us so we could discuss them in person.  If so, what times are you available for a meeting?  We are currently together as a group every Wednesday during class from 4:30-7:18 and can meet with you then if possible.  Also, we would like to know if it is possible to visit the biodigester that you have operating here at OSU. Thank you for your help.

 

Nathan Arroyo

Nathan--I am glad you are interested in the digester project. I would like to meet, but I am very busy with grants and teaching now. But, I hope I can help with email and you definitely visit the digester at Waterman. I am copying my student Alek on this email. He regualarly visits the digester, and can meet there someday. Please email him to coordinate a visit. The amount of organic loading is key. Often, this is measured in terms of KG of volatile solids (VS) per M3 of digester per day--kgVS/m3/d. Usually you want to this to be about .3 but there is a huge range for this loading (depending on temperature and many other variables). I recommend doing some research on fixed-dome digesters and seeing what is recommended. The frequency of loading is not that important as long as you get the organic loading right (it can be daily for every three days, or longer).

I hope this helpsJay

Budget

Team Biodigester’s Budget

Biodigester Supplies Estimated Cost ($) Actual Costmarkers 3 2scissors 2 1gloves 10 10posterboard 2 3laminating paper 5 5ruler 1 0duct tape 1 3pens 1 0filter masks 5 6goggles 10 8trash bags 5 5Craft Suppliesthread 5 15beads 5 0

Total 55 58

In-Country Work Schedule

Saturday, March 19, 2011:

Fly from Columbus, Ohio to Tegucigalpa, Honduras

Drive from the airport to Montana de Luz

Observe the orphanage’s campus and the biodigester area

Sunday, March 20, 2011:

Site see with the entire group

Preliminarily inspect the biodigester if time allows

Monday, March 21, 2011:

Clean/unclog the biodigester

Evacuate the gases from the gas pipe

Fill the biodigester with water

Tuesday, March 22, 2011:

Obtain the initial charge of biomass (most likely manure from a local cow farm or waste from the chickens on site)

Stir the contents of the biodigester

Wednesday, March 23, 2011:

Set-up the compost area near the biodigester

Mark buckets to obtain the correct ratio of water to solid for influent

Conduct chemical tests, including pH and chlorine levels, of the effluent and water

Thursday, March 24, 2011:

Make informative, pictorial posters regarding use of the biodigester

Train the staff responsible for operating the biodigester

Finish notes for the revisions to the operators’ manuals

Friday, March 25, 2011:

Finish anything necessary for the operation of the biodigester

Map Montana de Luz for future reference if time allows

Saturday, March 26, 2011:

Take any last chemical tests needed from the biodigester

Observe the outflow area of the biodigester for the last time

Pack belongings and clean-up after ourselves

Drive to the airport and fly from Tegucigalpa, Honduras, to Columbus, Ohio

Surveying Project

Purpose

When beginning the research process for projects this year and in the past, many teams found a need for information on the current status of different processes instated at Montana de Luz as well as the final statuses of previous projects. Since no organized method for storing project information existed, finding updates from previous teams or the current status of processes at Montana de Luz served as a challenge. In order to prevent this challenge from holding back future teams, a subproject this year included surveying the entire orphanage’s campus. All buildings were dimensioned and placed on an electronic map, which was then turned into a smart map by Brad Doudican so that project documentation available could be linked to the buildings on the map to which they are prevalent. Additionally, water and electrical systems were placed on the maps so that future teams can utilize this information.

Furthermore, on a fairly common basis, Montana de Luz randomly loses electricity, and their power is often not restored for at least a day. Since the water pump down the hill from the orphanage is powered by electricity, Montana de Luz is limited to the amount of water remaining in the towers on their campus until power is restored. If this stock of water is emptied, the orphanage runs out of water, including that for toilets, sinks, and showers. So that future project teams can have necessary data for power calculations to research a back-up power system for the water pump, finding the height of the water tanks and the change in elevation between the chapel and the water pump was necessary.

Results

o The buildings and distances between them were successfully surveyed and mapped, along with the electrical systems and water distribution systems.

o Height of water tanks: 18.9 feet

o Change in elevation between chapel and water pump: 97.12 feet

References

1. Dr. John Merrill: Led and structured class based on service learning for engineers,

Class placed large emphasis on the role of the citizen engineer in

society

2. Dr. Roger Dzywonczyk: Presented material pertaining to documenting and recording

work and data from research using “scope of work” method

3. Greg Bixler: Presented material concerning humanitarian engineering,

emphasized need for acknowledgement of difference between wanted and needed projects as well as the affect of projects on the local community.

4. Brad Dudican: Helped in development and troubleshooting of the implementation plan

for the biodigester at Montana de Luz. Also instructed the team on how to use the surveying equipment and made the smart map.

5. Dr. Jay Martin: Presented material about biodigester and aquaponics technology,

very informative in the initial stages of creating the biodigester project

and developing a plan of action.

6. Miriam Simon: Led weekly basic Spanish language classes.

7. Montana de Luz Staff: Provided information and schematics of the biodigester at Montana de Luz and the materials used in its construction. Specifically, Ruth coordinated the entire trip, made sure we had the necessary materials, translated when needed, and helped ensure the project was beneficial to Montana de Luz; Karin checked the Spanish translations for the posters and made sure they followed common Honduran terms; Saul made priceless suggestions on effluent removal and composting regarding the biodigester along with leading the building of the walls for the compost area; Alexandra

made suggestions on placement of the compost area to make it most useful to Montana de Luz.

8. www.appropedia.com: Contained great deal of information about the operation, usage,

maintenance, and safety of biodigesters. Provided pdf

download of operation manual of multiple biodigester designs.

9. www.wasteage.com/mag/waste_profiles_garbage_food/ :Provided information

concerning kitchen waste including density and percent water.

10. www.compost-info-guide.com/make_better_compost.htm: Provided details on the bestpractices in

composting.