UVM Extension Ag Engineering

The Biomass Beast, Rose Marie Belforti’s creation motivated by her interest in finding an on-farm use for excess manure and bedding. A mixture of manure and bedding are fed into the red hopper from above and the hydraulic press compresses the mixture to form a briquette. The briquette is solar dried and burns well in a wood stove.

Chris recently served as a technical advisor to Rose Marie Belforti on her recent NE-SARE funded project to demonstrate a hydraulic press used to make fuel briquettes from manure and bedding.  The machine, dubbed the “Biomass Beast” by Rose, was built for $5,766 and Rose demonstrated production of briquettes at a rate of 90 dry pounds per hour for 3 cents per dry pound.  The briquettes were found to have 6,481 BTU/lb (at 10.5% moisture content) which compared favorably to dry cord wood (e.g. 5,649 BTU/lb for sugar maple at 10% moisture). They burned easily and well. All in all, the cost of production and the heating value suggests that these briquettes deliver energy at a cost of about $4.4 per million BTU (roughly the equivalent of $105 per cord of firewood or $0.60 per gallon of fuel oil).

A fresh briquette is extruded from the press and is taken to dry.

Rose Marie Belforti was interested in finding ways to manage excess livestock manure on her small farm. She learned that manure fuel briquettes have been used on small farms by many cultures around the world for centuries, but typically they have been made by hand and do not have the energy content (BTUs) suitable for modern heating needs. Biomass fuel briquette machines currently on the market in the U.S. are designed for large production and are not practical for small farm use. Therefore, Belforti sought to design and test a prototype of an affordable hydraulic press scaled for small farm use that would sufficiently compress a mixture of raw manure and bedding mixture into brick form to be used as a heating fuel.

She was able to test the idea out with the support of a Farmer Grant project funded by the Northeast Sustainable Agriculture Research and Education Program (SARE). Belforti received the SARE Farmer Grant in 2017 to design and construct a hydraulic press to form fuel briquettes from livestock manure and to test them.

Belforti worked closely with a local welder, Steve Lonsky, and also with technical advisor Chris Callahan (UVM Extension Ag Engineer) to develop the press prototype. She then tested different ratios of fresh manure, bedding (straw and wood shavings), and water to come up with a recipe that would press and dry efficiently and have reasonable density. Briquettes were analyzed for quality and heat value. Compared to cordwood, livestock manure pressed briquettes rated well for BTUs per pound; however, ash content was higher than cord wood or wood pellets which means more frequent cleanout would be required.

A typical briquette was 7″x7″x9″ and was dried to 10.5% moisture using open air solar drying.

The press cost $5,766 ($2,103 in materials and $3,662 in fabrication labor) to construct which included all new materials except for tires. The cost could be considerably less if on farm equipment already in hand would have been used. One could also, with welding skills, modify a wood splitter to have a dual purpose machine.  A typical briquette size is: 7” high x 9” wide x 9” long. The dry weight is approximately 3 lbs for a briquette that size. Belforti was able to produce 90 lbs of dry briquettes per hour.  Drying is done in ambient conditions, protected from rain, using the heat of the sun (e.g. in a greenhouse) with some ventilating air flow.  The cost of fuel to run the machine is about 3 cents per pound of dry briquette.

The fuel testing demonstrated “dry” moisture content of about 10.5% using simple, passive techniques with some ventilating air flow but and no supplemental heating. The briquette fuel was tested for heating value and was found to have 7,673 BTU/lb (moisture free). This equates to 6,841 BTU/lb (at 10.5% moisture).  Ash content was relatively high at 18%.

Combining the cost of production and the heating value suggests that these briquettes deliver energy at a cost of about $4.4 per million BTU (roughly the equivalent of $105 per cord of firewood or $0.60 per gallon of fuel oil).  The amortized cost of the machine and labor is not included in these early cost estimates.

The proof in the pudding… a test burn showing the final result of all the project work.

Based on results of the project, Belforti concluded that livestock manure briquettes can be a feasible fuel source for the small farm, particularly those with surplus livestock manure. Photos of the press and construction information as well as fuel analyses are available on FarmHack (http://www.farmhack.net) and are included in the final project report, available on the SARE website (https://projects.sare.org/sare_project/fne17-862/)

Briquetting a Better, Burnable Cow Patty

The Biomass Beast, Rose Marie Belforti’s creation motivated by her interest in finding an on-farm use for excess manure and bedding. A mixture of manure and bedding are fed into the red hopper from above and the hydraulic press compresses the mixture to form a briquette. The briquette is solar dried and burns well in a wood stove.

Chris recently served as a technical advisor to Rose Marie Belforti on her recent NE-SARE funded project to demonstrate a hydraulic press used to make fuel briquettes from manure and bedding.  The machine, dubbed the “Biomass Beast” by Rose, was built for $5,766 and Rose demonstrated production of briquettes at a rate of 90 dry pounds per hour for 3 cents per dry pound.  The briquettes were found to have 6,481 BTU/lb (at 10.5% moisture content) which compared favorably to dry cord wood (e.g. 5,649 BTU/lb for sugar maple at 10% moisture). They burned easily and well. All in all, the cost of production and the heating value suggests that these briquettes deliver energy at a cost of about $4.4 per million BTU (roughly the equivalent of $105 per cord of firewood or $0.60 per gallon of fuel oil).

Continue reading “Briquetting a Better, Burnable Cow Patty”

Footprint Farm: Post Harvest Case Study – Video Series

Looking to upgrade your wash-pack space? Check out this interview with Taylor Hutchison from Footprint Farm talking about their motivations for building a new barn (house!) and including all the features they implemented to make it food safe and efficient. Stay tuned for a written case study, and a downloadable pdf coming soon. The playlist below features a 2.5min promo, an interview explaining the features of the wash-pack space (6min), more in-depth experiences and challenges from the build process (12min) and the last video showcases washing a batch of greens through their system (2min). Enjoy the videos!

Hanging Hoses

Having water when and where you need it can make a big difference in vegetable wash station efficiency. Planning for multiple “drops” or spigots around the wash area can make it more convenient to access water where it is needed. It can be helpful to consider the routing of the supply lines to avoid condensation on people and produce.  Cold water flowing through the lines on a warm humid day can result in condensation of water that can drop from the lines.  Running the lines away from walkways and produce areas can avoid this being a problem.  Running the lines down low in wash areas can also help keep any condensation exposure at a minimum.

Also, investing in a hose hanger, hose reel or a trolley can help keep the hose off the ground, resulting in a cleaner and more safe work environment. Continue reading “Hanging Hoses”

Bins, Buckets, Baskets & Totes

Many diversified farms have a variety of containers to best handle individual crops.

So you’re starting to farm, or scaling up your production. You hear talk about food safety, and cleanability.  You are checking out what other farms are doing and are looking for harvest crates and storage bins.

You probably noticed lots of people use many different things. Some use 5-gallon pails, milk crates, muck buckets, some use totes found at the box stores, yet others use what seem to be specific, grey, flip top totes. Does it matter what you use? Not really, but you should have some sort of method to the madness on your farm to help minimize contamination, reduce mix-ups and wasted time. Consistency is key to organization and efficiency.

I commonly hear “Ok, I like this style of totes/bins/crates, where do I find them?” Well, hopefully, this blog post will have a few suggestions to point you in the right direction with user reviews, distributor information, and pictures of features.  Continue reading “Bins, Buckets, Baskets & Totes”

Mighty Clean and Comfortable – A New Wash and Pack Shed at Mighty Food Farm

 Download this Postharvest Case Study as a PDF Here!

Lisa MacDougall has led Mighty Food Farm through start-up, relocation from rented land to owned land, and now through the construction of a brand-new 60 ft x 90 ft wash and pack shed. She’s done this all while producing a diverse mix of organic vegetables, tree fruit and berries on fourteen acres, now, in Shaftsbury.

The packshed has become the central “hub” of the farm boasting new, slab on grade construction with a large overhead door on the east side for receiving from field and packing out for market, person-door for crew access on the northeast corner, and a second person-door for retail and CSA access on the northwest corner.

One of Lisa’s primary goals in her new location was “a proper P-shed”; a pack shed where she and her crew could comfortably and safely wash, store, and pack produce for delivery to her customers year-round.  Mighty Food Farm serves retail farm stand, farmers market, CSA, and wholesale customers.

Continue reading “Mighty Clean and Comfortable – A New Wash and Pack Shed at Mighty Food Farm”

Lessons in Ergonomics from My Grandmother

I recently had the opportunity to record a public service announcement (PSA) for WDEV.  This is part of a series of PSA’s the UVM Extension colleagues contribute to. I decided to focus on ergonomics and shared some lessons from my grandmother and other sources. Click below to listen.

The text and additional resources are available below.

Continue reading “Lessons in Ergonomics from My Grandmother”

A Vegetable Farming “Must Have”: Harvest Tote

Every vegetable farm must have a harvest tote, and I don’t mean a basket for picking into. What I’m referring to is a box with the daily essentials in it so you’re never without, and don’t have to go back to the barn.

This “Just-In-Time” kit is taken right out of the Lean principles and works outstanding on the farm just as it does in the automotive or manufacturing industry. Lisa MacDougall of Mighty Food Farm in Shaftsbury, VT swears by this little blue box she calls the “Harvest Tote” which holds all the essentials needed for daily harvesting out of the field.

What’s should you have in the box?

  • Harvest Knives
  • Snippers
  • Scissors
  • Sharpening Stone
  • Rubber Bands
  • Harvest Log
  • Pen, pencil or marker

This box always gets placed in the truck, every morning. These essential tools are kept all together and in one place at all times minimizing time to look for tools, or trips back to the packshed because the rubber bands were forgotten. This reduces downtime and saves wasted steps leading to increased efficiencies of operation.

This kit has food safety benefits too! With all the tools stored together, they are cleaned and sanitized all at the same time and logged, usually on a weekly basis. This Friday afternoon cleaning is also an opportunity for a weekly sharpening so all tools are in good shape for the week ahead. Keeping the tools in a tote keeps the knives from getting used for other activities outside of harvest which could contaminate them and make them dirty. Keeping the knives in a tote, also ensures that they are not stored in a hard to wash sheath, tossed on the dash of the truck, cup holder of the tractor etc.

Implementing this standard has many benefits and could be a great tech-tip to consider on your farm.

Postharvest Resource Survey

We are seeking input regarding a research and education project with the goal of consolidating postharvest information in a single set of resources.

Our proposed project aims to consolidate existing knowledge, best practices, and new developments in postharvest equipment, infrastructure, and buildings into a web-based handbook, workshop curriculum / educational materials and recorded videos.

Click here or on the picture to take the survey! 

This survey is voluntary and anonymous. Summarized and anonymized results will be included in a grant project proposal and also on our website (go.uvm.edu/ageng). Please direct any questions to Chris Callahan, chris.callahan@uvm.edu, 802-447-7582 x256.

The survey should take an average of 3 minutes to complete.

Thanks for your help.

Construction Details for a Counter-top Forced Air Cooler

To learn more about forced air cooling visit go.uvm.edu/forcedaircooling

To download the PDF version of this plan click here!


Farms that need to cool smaller volumes of produce can also benefit from forced air cooling. Whether cooling stacked pallets, pallet bins or individual cartons, the same principals apply. A smaller pallet cooler was noted on the previous page, but this concept can be scaled down even further to fit your needs. Here is a prototype, that could fit on a countertop with-in a walk-in cooler.

Framing:

Constructed of 2×4’s on top of a horizontal base made from 1/2” plywood cut 24” deep and 44” wide. Angled reinforcements were needed to stiffen the assembly.

Plenum Panel:

Continue reading “Construction Details for a Counter-top Forced Air Cooler”

Construction Details for a Pallet Forced Air Cooler

The blower is just placed up to the cut-out hole, on a shelf. This unit has a very simple shelf and feet to add some stability.

To learn more about forced air cooling visit go.uvm.edu/forcedaircooling

To download the PDF version of this guide click here!


Framing:

2”x12” lumber to make a 43” wide x 74” tall x 11-1/4” deep plenum for suction air distribution.

Plenum Panel:

3/8” CDX Plywood with an 11-1/4” circle cut out for the blower suction inlet. Position this whole centered for even air pressure.

Plastic Wrap:

Continue reading “Construction Details for a Pallet Forced Air Cooler”

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