EasyDry M500 Manual

Assembly, Operation, Maintenance, and Costs of the EasyDry M500 Portable Maize Dryer AflaSTOP: Storage and Drying For Aflatoxin Prevention

February 2017

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The AflaSTOP: Storage and Drying for Aflatoxin Prevention (AflaSTOP) project is identifying the most promising storage options to arrest the growth of aflatoxin and designing viable drying options that will allow smallholder farmers to dry their grain to safe storage levels. The project works to ensure that businesses operating in Africa are able to provide these devices to smallholder farmers. It is jointly implemented by ACDI/VOCA and its affiliate Agribusiness Systems International (ASI) under the direction of Meridian Institute. For more information on AflaSTOP and other key reports and resources, visit: www.acdivoca.org/aflastop-publications.

This work was carried out as a partnership with Catapult Design to identify potential drying technology suited to support post-harvest handling devices for maize smallholder farmers.

Marius Rossouw was the lead designer.

For any inquiries about the EasyDry M500, please contact us at info@easydry.org A video providing key operating messages and detailing how to incorporate the EasyDry M500 into your post-harvest workflow can also be found at http://www.acdivoca.org/easydryoperators/.

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TABLE OF CONTENTS 1.

Product Overview ................................................................................................................ 5

2.

Safety Warning.................................................................................................................... 7

3.

EasyDry M500 Components................................................................................................ 8

4.

EasyDry M500 Assembly Procedure ................................................................................... 9

5.

EasyDry M500 Operation ...................................................................................................13

6.

Maintenance, Major Repair, & Associated Costs ................................................................16

7.

Troubleshooting .................................................................................................................19

8.

How to Charge for the EasyDry M500 Drying Service ........................................................20

9.

Sample Costing Breakdown ................................................. Error! Bookmark not defined.

LIST OF TABLES Table 1: EasyDry M500 Attributes .............................................................................................. 6 Table 2: EasyDry M500 Components......................................................................................... 8 Table 3: EasyDry M500 Assembly Procedure ............................................................................ 9 Table 4: EasyDry M500 Operation ............................................................................................13 Table 5: EasyDry M500 Maintenance Schedule ........................................................................16 Table 6: Predicted EasyDry M500 maintenance costs ..............................................................17 Table 7: EasyDry M500 Troubleshooting ..................................................................................19 Table 8: Calculating How to Charge for the EasyDry M500 Drying Service ...............................21 Table 9: Sample Viability Scenario for Tanzania ......................... Error! Bookmark not defined.

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1. Product Overview The EasyDry M500 is a highly mobile maize dryer targeted at servicing smallholder farmers who struggle to dry their maize after harvest and then have problems with mould and discolouration in their stored maize. AflaSTOP developed the EasyDry M500 as an open source technology that can dry maize in batches of 500kgs, lowering the moisture level from 18 to 20% to approximately 13.5% (recommended level) in 3 hours, with the aim to dry three batches per day in one location. It has been piloted in Kenya, Tanzania and Rwanda to date. It offers a solution that closely resembles the traditional method of lying shelled maize out in the sun to dry, with the major difference in that forced hot air is used as the drying mechanism and is capable of operating under poor weather conditions including rain since it relies on burning biomass (maize cobs) to generate the required heat, and not the sun and has a rain cover to cover the maize bed if its raining.

Shallow-bed Saturated Drying Air

Drying Air Supply Unit

The dryer is either transported (as a service) on two motorbikes, on a pickup truck, a trailer or handcart or stored at the location (as an on-farm investment) where maize is shelled or dried.

The dryer can be assembled within 10 minutes by erecting the modular shallow-bed and connecting it to the drying air supply unit. ± 500 Kg of “wet” maize (10 x 50 kg bags, 5 ½ x 90 kg bags, 4 ¼ x 120 kg bags - ± 50kgs will not effect drying performance) is loaded onto the shallow-bed and the furnace is ignited.

The heated clean air needed for drying is generated through convection heat transfer by blowing ambient air over heated heat exchanger (HX) channels. The HX channels are heated by drawing hot furnace exhaust gasses through them and out the chimney. The hot exhaust gasses are constantly generated by steadily burning fuel (maize cobs) in the downdraft furnace.

The heated air is blown into a canvas plenum with maize suspended on a perforated mesh bed

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above it. The air pressure builds up in the canvas plenum and forces heated air past the maize kernels with surface moisture drawn away.

The maize is stirred at 30-minute intervals to allow the moisture trapped in the lower layers closest to the heated air to escape. Once dry, the maize is offloaded for storage. The dryer can dry the 500 kg “wet” maize (~20% moisture content) down a safe storage moisture content of +/13.5% within four (4) hours (+/- an hour depending on the actual moisture content of the maize) and 500 kg of maize of ~16% moisture content to below 13.5% within 90 minutes. Multiple batches can be handled per day depending on starting moisture levels and operating hours. In fact to provide an economically viable service three batches must be processed per day.

Table 1: EasyDry M500 Attributes Attribute Complete Dryer

Drying Air Supply Unit Tangible

Shallow-bed Unit

Size - Operation

2.4 m (W) x 3.3 m (L) x 1.8 m (H)

1.0 m (W) x 1.6 m (L) x 1.8 m (H)

1.9 m (W) x 2.5 m (L) x 1.2 m (H)

1.5 m (W) x 1.5 m (L) x 0.9 m (H)

0.5 m (W) x 1.3 (L) m x 0.9 m (H)

1.0 m (W) x 1.5 m (L) x 0.9 m (H)

Size Transportation

Color/s

Various

Weight Material composition

190 kg Local, low cost material to promote sustainability Stock, Painted/ Painted Heat Resistant

Finish

Agricultural colors – Heat resistant 120 kg Mild Steel, Cast Iron, Plastic, Copper, Aluminum Stock, Painted/ Painted Heat Resistant Intangible

Stock PVC and Canvas Agricultural colors - Bed 70 kg Mild Steel, Canvas, Rubber, Leather, Plastic Stock, Painted

Efficiency/Capacity

Dry 500 kg wet maize (+/20% moisture content) down to 13.5% in +/- four (4) hours (+/- 2 hours depending on actual moisture content of the maize)

Consumes 12 - 15 kg cobs and 450 ml petrol/hour.

Recommended capacity of 500 kg

Projected Durability/Longevity*

5 years

5 years

5 years**

Lubricate bearings and check engine oil weekly, Repair lesions in canvas Service engine monthly, and coffee mesh as they Replace HX panels every 2 occur. years. * Durability/Longevity with proper care, maintenance and associated cost. ** Canvas plenum and coffee mesh may wear through first and may need repair/replacing more often.

Projected Maintenance Schedule

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2. Safety Warning The EasyDry M500 is a dangerous piece of agricultural equipment that consists of moving components and hot surfaces, posing possible injury risks. Extreme caution is required around the furnace area, the engine and v-belt assemblies. Children should be kept away from the aforementioned components at all times with bystanders minimized around these areas where possible. Children should be kept away at all times while the dryer is in operation. Do not use indoors unless well ventilated.

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3. EasyDry M500 Components Table 2: EasyDry M500 Components

1 x Shallow-bed

1 x EasyDry M500

1 x Drying Air Supply Unit

1 x Rainfly 2 x Collapsible Bed Panels

1 x Cob Drying Basket 1 x Canvas Plenum

2 x Transportation Handles

1 x Main Drying Unit Body 1 x Padlock

1 x V-belt 1 x 5.5 HP Engine 1 x Center Support Post 1 x Connection Pin 4 x Collapsible Support Frames

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4. EasyDry M500 Assembly Procedure Table 3: EasyDry M500 Assembly Procedure

Step 1: Set Up

Step 2: Site selection and area preparation.

Transport the dryer to suitable drying location. Select relatively even terrain – 3 m x 4 m with the 4 m length of the operating area established in the direction of the prevailing wind.

Prepare the drying area by removing any object that may puncture the plenum. Place the drying air supply unit and plenum (with sides folded inwards to identify its footprint) with the drying air supply unit down wind of the plenum.

Step 3: Shallow-bed assembly.

Step 4: Interlocking the bed support frames.

Unfold one collapsible bed support frame (90Âş) and place at one corner of the plenum.

Repeat Step 3 and connect the first unfolded bedframe with a second by slotting the pin of the first bedframe into the receiving catch of the second bedframe.

Step 5: Completing the bed support frame.

Step 6: Securing the plenum.

Repeat Step 4 until the bed support frame is complete. Ensure that all connecting pins are properly engaged and that all corners are as square as possible.

Connect the sidewalls of the plenum to the inside of the bed support frame by hooking the perimeter rope of the plenum onto the bed support frame’s corresponding clips.

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Step 7: Placing the first collapsible bed panel.

Step 8: Proper panel nesting.

Flat bar overlap

Smooth out the canvas to ensure minimal creasing by making sure the bottom corners are close to the bed support frame’s legs. Unfold collapsible bed panel 1 (with the overlap flat bar) and place it into the bed support frame and plenum. Collapse the panel slightly to reduce the span and place the bed panel into the plenum with the underside of the perimeter angle iron slightly above the bed support frame square tubing before lowering the center of the panel, pinching the canvas in the process between the panel angle iron and bed support frame square tubing.

Ensure that collapsible bed panel 1 nests properly onto the bed support frame with the maximum overlap of the perimeter angle iron resting on the bed support square tubing on 3 sides.

Step 9: Supporting the first bed panel.

Step 10: Placing the second collapsible bed panel.

Place the center pole under collapsible bed panel 1 to support the center. Ensure correct installation by orienting the center pole horizontal square tubing, nesting under the horizontal angle iron edge and not the hinges.

Place collapsible bed panel 2 in the remaining opening by repeating Step 7 with the inner angle iron overlapping the protruding flat bar of collapsible bed panel 1.

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Step 11: Proper panel nesting.

Step 12*: Rainfly installation

Ensure the maximum contact between the collapsible bed panels and the bed support frame by confirming that the bed support frame sits well within the perimeter angle iron of the collapsible bed panels, especially at the pin connections.

Install the rainfly by placing it over the center pole and connecting all the corresponding cornets to the bed support frame corner stanchions.

Step 13: Ensuring a seal between the furnace and the ground

Step 14: Securing the plenum-connecting duct.

Place the drying air supply unit within connecting distance from the erected shallow-bed. Place the unit on level ground and ensure that the airflow indicator plate is just touching the HX panels and not leaning away. Test-fit the plenum’s duct connection to the drying air supply unit and confirm that the ground underneath the furnace is even enough so that no gaps between the underside of the furnace and the ground are visible. If gaps are visible, build soil up around edges to create the seal. This is required to prevent flames from leaking out the top, as all combustion air will be introduced from above, drawing the flame through the heat exchanger.

Fill the engine with sufficient fuel (at least 3 liters for one batch), check the oil and lubricate all the bearings with high temperature (150 ºC) lithium grease. Ensure that the internal air supply fan bearing is sufficiently lubricated by viewing the bearing through the spaces of the heat exchanger panels. Connect the plenum’s duct to the receiving connecting ring on the drying air supply unit and tighten the connection strap securely. Adjust the drying air supply unit’s location to minimize creasing of the connecting duct to prevent pressure losses.

*Step 12 Rainfly to be installed after maize is loaded on the bed only if rain is expected.

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Step 15: Installing the engine assembly

Step 16: Erecting the chimney.

Remove the engine assembly from its transportation stowage by removing the padlock and locking pin and install it onto the receiving support angles on the opposite side of the furnace.

Be sure the replace the padlock, as this will prevent the connecting pin from coming undone during operation.

Erect the chimney by pivoting it upward from its stowing position until it rests securely on the dyer body under its own weight.

Step 17: Installing the v-belt.

Step 18: Placing the cob-drying basket.

Install the v-belt onto both fan and engine pulleys by lifting the back end of the engine to reduce the span. Releasing the engine will tension the v-belt.

Ensure that the engine hangs freely on the v-belt with no obstructions underneath.

Remove the cob-drying basket from its stowing location within the furnace and place it on top of the chimney with cobs in it. The EasyDry M500 is now ready for operation.

Caution: A moving v-belt poses potential danger as loose clothing or appendages may get caught between the v-belt and the pulley.

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5. EasyDry M500 Operation http://www.acdivoca.org/easydry-operators/ Table 4: EasyDry M500 Operation

Step 1: Loading the maize.

Step 2: Filling the cob basket with wet cobs.

Load the shallow-bed with about 500 kg (10 x 50 kg bags, 5 ½ x 90 kg bags, 4 ¼ x 120 kg bags ± 50 kgs will not effect the drying performance) of maize to be dried. Best practice is to spread each bag before adding the next. This mixes the maize to promote more homogenous drying. Level the maize and ensure that the grain depth is equal (within 1 cm) throughout the maize bed. This is necessary to ensure consistent airflow throughout the bed.

If not full, remove, fill and return the cob drying basket from/to the top of the chimney. Dry cobs are needed to fuel the furnace efficiently and the initial ignition of the furnace using other flammable material will assist in supplying dry cobs if none are available. It is sensible to bring dry cobs from the day before to use for the first 30 mins to get a hot fire quickly. If you do not dry the cobs before using them the fire will be cooler and it will take longer to dry the batch of maize.

Step 3: Igniting the furnace.

Step 4: Starting the engine.

Open the ash cleanout door downstream of the heat exchanger to allow for extra combustion air when igniting the fire. Prepare and light a fire in the furnace with grass, twigs, paper, etc. and slowly add dry cobs until a well-established fire with sufficient burning cobs remains. Close the ash cleanout door once again, creating the required seal between the ground and the furnace.

Start the engine by raising the backend of the assembly with one hand (this will minimize the starting torque requirements of the engine) and pulling the staring cord with the other hand. Release the engine assembly slowly to engage the v-belt and subsequent fans only once the engine has reached a steady idling speed. Initial throttling may be required to overcome the fan inertia.

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Step 5: Engine RPM adjustment - airflow indicator.

Notch

Be sure to reduce the RPMs to the required rate (as specified by the airflow indicator) once the fans are up to speed. Adjust the engine RPM throttle to have the airspeed indicator needle point to the notch in the needle protection member. The faster the air moves, the cooler the hot air is, and the slower the maize dries, and the more petrol is used.

Step 6: Feeding the furnace.

It is very important that the furnace is fed at a constant cob feed rate with cobs that have been dried/preheated in the cob-drying basket. At no point should the cob level fall below the top level of the furnace grate. Under and over feeding will result in low furnace temperatures and longer drying times. 1215 kg/hour (1/2 bag) cob feed rate is desired.

Caution: The furnace body of the dryer gets extremely hot and poses danger of severe burns upon contact.

Step 7: Viewing the furnace for flames.

Step 8: Stirring the cobs to introduce oxygen.

Always ensure that the furnace is firing as hot as possible by confirming flames through the peephole on the topside of the furnace body. The bottom peephole is used to confirm that the charcoal buildup in the bottom of the furnace is not constricting to fire from passing through the HX. If this is the case, make sure to remove the buildup as per Step 11 below into a hole behind to the furnace body.

If no flames are visable either the furnace cob level is too low or the cob combustion has moved into the charcoaling stage. This is not desirable as flames are needed to heat the heat exchanger effectifly. Stir the charcoaled cobs and add fresh dry cobs to ignate flames again.

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Step 9: Drying cobs in the cob-drying basket.

Step 10: Processing the maize.

Continuously move cobs from the cob-drying basket to the furnace. Cobs are considered dry enough if they break with limited flex. Excess dry cobs can be placed in a bag or on the ground to be used to start the furnace at the next batch. A lid is provided to protect the cob drying operation in the event of rain.

The lid should remain open if not raining for best drying results.

Stir the maize every 30 min using an implement (bucket, rake, etc.) or by hand. Ensure that maize from the bottom of the grain bed is replaced with maize from the top. A proven method to achieve this is to mix in a circle, first create a space down to the bed, then move maize from the top into gap, so the cooler wetter maize on the top, moves down closer to the stronger heat. Be careful not to damage the bed panel coffee mesh if implements are used. Be sure to level the maize bed again after processing and confirm equal maize bed depths.

Step 11: Stopping the drying operation between batches.

Step 12: Maintenance between batches.

When the desired maize moisture is achieved, stop feeding the furnace and stop the engine. If refueling is required, wait until the majority of cobs within the furnace have been consumed with no visible flames before opening the fuel container. Using a bucket or by hand, offload the maize into empty maize bags*.

Again, use caution not the damage the bed coffee mesh when scooping maize. Lift the furnace end of the drying air supply unit and remove any charcoaled cobs that may have accumulated in the furnace body.

This is required to ensure that no obstructions exist in the way of the combustion gasses flowing through the heat exchanger.

Open the ash removal door downstream of the heat exchanger and remove any ash that may have accumulated during the drying operation. Allow the furnace to die down before refueling the engine (if required). Grease all the bearings if required.

* Let the maize cool down in the bags overnight before administering insecticide. If offloading into hermetic storage, allow the maize to cool before storing.

Step 13: Putting down the machine Disassembly is executed in the reverse assembly order. Only return the engine assembly to its stowing position once the adjacent metal has sufficiently cooled. When loading, make sure that the plenum and collapsible bed panels are protected from sharp objects to prevent damage.

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6. Maintenance, Major Repair, & Associated Costs Below follows a breakdown of the best practice maintenance and major repair schedule including associated cost following a full assessment of the EasyDry M500 after being in use for the estimated drying season of 40 days. It should be noted that Operators have varying levels of mechanical knowledge and either over apply items like grease, or fail to remember to apply it at all. An example of this; every bearing requires 1.3 grams of grease per application with the hot bearing requiring grease once a day and the cold bearing twice a week. This brings the total grease requirement per 40-day season to 135 grams for the entire dryer. The human behavior around greasing however is to grease every day (or not at all in some cases) and when applied use so much grease it oozed out of the bearings, which used closer to 500 grams per season than the actual required level of 135gms.

Table 5: EasyDry M500 Maintenance Schedule

Daily Schedule: Refill petrol and check oil levels

Clean ash from furnace body and exhaust chamber

Lubricate hot bearings

Refill petrol @ 0.45 l/hour of operation Remove ash and charcoal Clean plenum

Monthly Schedule: Service engine by changing oil and cleaning air and fuel filter

Check v-belt for fraying

 

Clean fire grate and HX from ash buildup

Lubricate cold bearings – twice/week

Clean plenum from dirt before stowing away   

Weekly Schedule:

Inspect plenum and rainfly for tears

  

Lubricate bearings Clean fire grate Check plenum and repair holes if required  Check bed mesh and repair holes if required Seasonal Schedule: Check and replace furnace body and fire grate if burned out Check and replace HX panels if burned out by removing the rear panel

 Service engine.

Check v-belt.

Inspect bed coffee mesh

  

Check and replace HX panels if required.

Check and replace furnace body if required.

Check and replace fire grate if required.

Check and replace bed mesh.

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Table 6: Predicted EasyDry M500 maintenance costs

Unit Price (KES):

Total Cost (KES):

As needed. Minimal top-up between oil changes. Sold in 1liter ml bottles. 600 ml for complete oil change.

1

Excess from oil change to be used.

0.00

N/A

0.00

1

N/A

0.00

Lubricate hot bearings (High temperature lithium grease 150⁰ C) Daily Total Weekly Schedule Clean fire grate and HX from ash buildup Inspect plenum and rainfly for tears Lubricate cold bearings – twice/week Inspect bed coffee mesh Weekly Total

Recommended 2.6 grams but will likely use 5 grams.

Sold in 500 gram pots.

400

4.00

Maintenance Task:

Maintenance Task: Daily Schedule Check oil levels (SAE 40)

Clean ash from furnace body and exhaust chamber Clean plenum from dirt before stowing away

Monthly Schedule Service engine by changing oil and cleaning air and fuel filters Check v-belt for fraying Monthly Total Seasonal Schedule Check and replace furnace grate if burned out

Check and replace furnace body OR Check and patch furnace body

Quantity:

4.00 1

N/A

0.00

1

N/A

0.00

2

4.00

8.00

1

N/A

Quantity:

Unit Price (KES):

0.00 8.00 Total Cost (KES):

1

600.00

600.00

1

N/A

0.00 600.00

1

Material – 1,000.00 Labor – 1,000.00 Material – 800.00/200.00 Labor – 500.00/300.00 Material – 4,000.00 Labor – 1,500.00

2,000.00

200.00

200.00 5,850.00

1

Check and replace HX panels if 0.5 burned out by removing the rear panel. HX should last 2 seasons with above mentioned design changes Patch plenum and/or rainfly 1 Seasonal Total (most likely scenario)

1,000.00 or 800.00 (Av 900) 2,750.00/ season

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Total Maintenance for 40-day operation Daily Total 40 Weekly Total 6 Monthly Total 2 Seasonal Total 1 Total Predicted Cost

4.00 8.00 600.00 5,750.00

160.00 32.00 1,200.00 5,750.00 7,242.00 OR 181.05/day

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7. Troubleshooting A video guide on fabrication details can be found at http://www.acdivoca.org/easydrymanufacturers/.

Table 7: EasyDry M500 Troubleshooting

1.

Symptom Collapsible bed panel 1 does not fit properly.

Shallow-bed Probable Causes Solution/s Improper bed support Ensure that the all the collapsible bed frame assembly. support frames are connected properly and that the frame as a whole is square.

Improper collapsible bed Ensure that collapsible bed panel 1 is nested panel 1 installation. properly.

2.

Collapsible bed panel 2 does not fit properly.

3.

Maize leaking into the plenum.

Gaps between Collapsible bed panel 1 and 2 and/or bed support frame.

4.

Uneven drying throughout the maize bed.

5.

V-belt is slipping.

6.

Noisy bearings.

7.

Fire escaping out the top of the furnace postinitial furnace startup.

Uneven airflow through Ensure that the maize bed is level and equal the maize bed (uneven maize thickness throughout the bed. chaff accumulation is an indication of uneven airflow) Drying air supply unit Insufficient belt tension.

Ensure that the engine assembly hangs freely with only the v-belt supporting it.

Insufficient lubrication.

Ensure all bearings are lubricated at all times.

Insufficient seal between Confirm that a good seal is achieved the bottom of the furnace between the furnace bottom and the ground and the ground, ash and that no combustion air is being buildup under the fire introduces from the bottom. Remove any grate or the ash cleanout ash/charcoal that may be obstruction airflow door is open. and ensure the ash cleanout door is closed.

8.

Excessive smoke from the chimney.

Insufficient combustion air or wet fuel source.

Furnace is over fueled or the ash cleanout door is open. Cobs are too wet for efficient combustion.

Ensure that the proper amount of dry cobs (from the cob drying basket) is fed to the furnace at regular intervals. Cob levels should always lie around the top of the fire grate.

9.

Longer than expected drying times.

Low drying air temperature, in insufficient airflow or higher than anticipated grain moisture content.

Ensure that the furnace is always fired as hot as possible. Confirm constant flaming through the heat exchanger through the peepholes on the side of the furnace. Stir the furnace and introduce more cobs if limited flames are visible. Ensure that sufficient drying air passes through the maize bed by ensuring the engine RPMs are set to the derided rate as indicated by the airflow indicator.

Ensure that collapsible bed panel 2 has a sufficient overlap with collapsible bed panel 1 and that the perimeter of both panels has sufficient overlap with the bed support frame.

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8. How to Charge for the EasyDry M500 Drying Service The tables below are designed to help the EasyDry M500 Operator decide what he/she needs to charge farmers for the drying service. An excel template that can be tailored to each operator/entrepreneur’s country, exact circumstances and costs can be found at http://www.acdivoca.org/easydry-operators/. For now, the examples below are illustrative of what variables affect an operator’s costs and profitability in Kenya drying 90kg bags.

As in any business running the EasyDry M500 is made up of fixed costs (salary, transport, profit expectation) and variable costs (petrol, maintenance). Over 75% of the costs are fixed costs – this means whether the operator manages one batch, or 3 batches the cost is the same; e.g. salary a person expects per day. This means if the operator only dries one batch in a day the cost of drying is much higher than if three batches are dried at the same location. In fact to be profitable, the operator MUST dry three batches per day. It takes time to take down the machine, move to a new location, and set up again. Therefore, the probability is that operators will need to service farmers with 1.5mt of maize to dry or more, or a number of farmers who bring their maize to the same location to dry.

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Table 8: Calculating How to Charge for the EasyDry M500 Drying Service

FX rate Kg/bag Hours/day Days of work per year Fuel cost per litre Estimated daily transport cost Estimated daily salary Estimated cost of dryer Bags/batch KGs/batch Estimated hours/batch Scenarios Investment costs Years to pay back Days of use per year Daily profit/repayment Other variables Maintenance per year Fuel per liter Operating costs Maintenance costs per day Transport Operator salary Fuel Total daily costs (KES) Batches Cost per bag (KES) Cost per kg (KES) Cost per bag (USD) Batches per day 3 2 1

$1 = Ksh 100 90 9 40 100 370 800 85,000 5.5 500 3.0

1

2

3

4

Farmer Group

85,000 2 40 1,062.50

85,000 3 40 708.33

85,000 2 30 1,416.67

85,000 3 30 944.44

85,000 4 40 531.25

7,120.00 100

7,120.00 100

7,120.00 100

7,120.00 100

7,120.00 100

181 370 800 490 2,903.50

181 370 800 490 2,549.33

181 370 800 490 3,257.67

181 370 800 490 2,785.44

181 370 800 490 2,372.25

3 175.97 1.96 $1.76

3 154.51 1.72 $1.55

3 197.43 2.19 $1.97

3 168.63 1.88 $1.69

3 143.77 1.60 $1.44

Cost per bag 175.97 243.62 446.58

154.51 211.42 382.18

197.43 275.82 510.97

168.81 232.89 425.11

143.77 195.33 349.98

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