Examples in Practice

Examples in Practice

Rule of thumb to be safe = 0.5 gals per sq. ft. per day in good soil, sandy loam.

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https://extension.missouri.edu/publications/eq401

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Good, thus expensive, float switch. Law may require hi or low water alarm too.You need a low water cut off float for sure so you don’t burn out the pump. You can get a board with these connections and a start capacitor to make wiring clear and easy—diy repair. Perc-Rite will show you examples of all this stuff.

https://www.amazon.com/Heavy-Duty-Suspended-Wastewater-Mercury-Free-Self-Orienting/

Floats:

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Think about water level and instructions to the pump:

1. water level is below X inches, float is down (always off type), thus pump is off. Water rises to Y mark and float is now active—circuit is closed inside. Reverse is true when water goes down.

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2. Master float fails and water fills over top. You need a high water float with an alarm.

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3. If pump stay on and all the water is pumped out, you need a lo-water float that turns off the pump or initiates an alarm. All different floats.

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2025 - Scalable IBC Tote Digester. Just keep adding in this proportion of totes.

Tote 1

Tote 2

Tank 4

Tote 3

Tote 4

Effluent pumped to orchard or to woodchip pit

water

3 PSI gas output

Water for water displacement of

tank 4

IBCs are not designed to be pressure vessels. However, each IBC is production tested to 3 PSIG, and design qualification tests, required for U.N. marking of an IBC, vary from 14.7 PSIG to 62 PSIG. Working test of 2.1 meters.

Digester Stack

filled to 7’

(3psi)

water

gas

gas

water

air

Vent open to air. Can handle methane gas overflow.

Purifier

Compression to 140 PSI

2:1 straw:nuggets

1000 g MaP.

0.1 gal nuggets

gas

water

Grass Feed behind building

Grinder Pump $249

Water displacement tube connection

1. Tank 3 starts full of water.
2. Gas pushes water out of 3 into 4
3. When gas is pumped out of 3 into pig, water is sucked back from 4 into 3. Key is to keep end of water displacement tube at bottom of Tote 4, under water.

Pig

Grinder Pump $700

Drip

Disc filters

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Gas Collect

Septic effluent leaves the tank and graivy feeds into the pump vault (un-filtered) and then the pump comes on, selects a field and jets effluent into the disc filter on that side. This cleans the water enough to flow easily thro the pipes and emitters.

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I don’t even use a grinder pump in any vault. here—just a 110 deep well pump—does great for 21 years now.

Portobiopotty Solar Energy Trailer and Waste Center

8x16 trailer for jobsites, or home addition for lawnmowing areas.

• 500 gal flush capacity runs efficient toilet for 1000 flushes, or 10 days time for a 24 person crew at 4 flushes per day.
• PV on top with rainwater collection to totes 7-8
• Digester totes
• Clean Water supply totes
• Gas displacement totes
• Effluent Totes - digestate fertilizer

Tote 1

Tote 2

Tote 3

Tote 4

Tote 5

Tote 6

Tote 7

Tote 8

Pot

Purifier

Compression to 140 PSI

Garbage Macerator feed.

Can feed grass clippings, food waste, paper, organics

Digester Heating System

Add small filter for pump (also shows water level)

Heating Coil - 300 feet under the totes - ½”�Pressure loss total 10PSI through 600’ of ½” PEX at 1 GPM.

Tote

Hillbilly Heater

2” drain from Digester

Next to wall, such that piping from digester allows the drain to be next to the wall

⅜” vinyl tubing

To Drain

Tee into existing Water Supply

To forced air exchanger

Will also be used for forced air heating

Supply Valve

Priming Valve

Expansion Tank

Circulating Pump

Biodigester BOM

Plumbing

1. [2] 2” cam-lock to NPTM - $29
2. [2] 2” PVC adapter, NPTF to slip, $1.2
3. 40’ 2” PVC - $20
4. [10] 2” elbow - $10
5. [7] 2” tee - $10.5
6. [1] 2” valve - $11
7. 20’ 1” PVC - $3.4
8. [3] 1” tee - $3.9
9. [2] 1” check valves - $17.1
10. [4] 1” ball valve $18.4
11. 1” Vinyl Tubing - $15.6
12. [2] clamps for 1” - $2
13. [2] 2” threaded cap - $4 + [2] 2” plug - $3

Pump

• Macerator Lift Pump - $150
• 3” flexible coupling $5
• 3” PVC stub - connect 3-2” reducer to pump - $5
• 3”-2” bushing - $2

Automation

• On-off timer with 15 minute resolution
• [1] Hillbilly Pump - $30
• Arduino with Backlit Display for Temperature and heating. If tubing is hot and digester is cold - turn on pump. Pump runs from PV DC, 24V.

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12V 16A

Macerating Pump

(PDF manual)

1. Note: missing the cleanout plug on top digestger in BOM. Screw in plug is probaby best..

Biodigester BOM

Gas Stack

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Vents - 3” drain requires 2” vent (source)

1. [1] 3”-2” reducer $2
2. [3] 2” tee $4.50
3. [4] 2” elbows $4
4. [3] 1” elbows $1.5
5. [1] 2”-1.5” reducer $1.5
6. 20’ 2” PVC $10
7. 10’ 1” PVC $1.69

Gas Storage

1. [2] 2” to 1” bushing - $2.7
2. [2] 1” to ½” bushing - $1.2
3. 30’ ½” PVC pipe - $3.75
4. [2] ½” PVC elbows - $0.44
5. [1] ½” PVC tee - $0.27
6. [2] ½” gas valve $1.93
7. 3 cu m Gas Bag + ship - $164
8. [1] ½” PVC to NPT - $0.4
9. [1] ½” CPVC male adapter - $0.23
10. [1] ½” hose clamp - $0.79

Gas Usage

1. Cooktop
2. ¾” PVC pipe
3. ¾” to ½” reducer
4. ½” stub as barb for ¾” gas pipe
5. ¾” hose clamp

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3” PVC Drain - reduce to 2”

2” PVC Tee

Long Vent - 2”

Long Drain - 2”

May need turns

1” Feed Pipe

May need bend along wall

2” vent pipe

From Toilet + Sink

Bug Screen + Retaining Collar

2”-1.5” reducer - pipe would go inside of it via 1” clear hose for visibility

1” clear hose - ¾” pressure relief goes inside of it for visibility of weep (if faulty pressure relief)

½” gas pipe

¾” pipe from gas bag to house

½” pipe to gas bag

Hillbilly Heater Drain

Biodigester BOM

Notes

1. Outlets are on the front and top of totes
2. Drill out holes in tote first
3. Optimize for parallel build
4. Allow for complete disassembly - front panels can be taken off for servicing without having to cut through PVC

Heat Enclosure - $212.50

• [7] 2x4s, 96” long - $23
• [16] 2x4s, 93” long - $47
• [5] ⅜” plywood sheets - $71
• Insulation - $30+$15
• Box of 6” screws - $9
• Paint - $12.50 for silicate + calcium chloride $5

Heating

• [1] PEX coil or black poly pipe coil - $47
1. PEX is better if stove heat is used
• [1] Pump - $30
• [1] Expansion tank, 40 PSI - $30
• [1] ½” Check valve - $12
• [2] ½” PEX to NPTM - $2
• [2] crimp rings - $0.6
• [1] Filter -
• [1] ½” PEX tee - $1.1
• [1] ½” PEX valve - $7

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This one says 140F,

+ similar is 110F.

Tools

1. Cordless drill
2. 1.75” hole saw
3. 3” hole saw
4. Flat head screwdriver for hose clamps
5. Hack saw for cutting PVC pipe
6. Start bit #25 for star drive screws
7. PEX crimp tool
8. PEX crimp removal tool
9. ​

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Gas Bag Structure

Gas Bag Piping Detail

1. Delivery gas line to gas bag
1. ¾”
2. Electrical outdoor UV-proof conduit
2. Water trap:
• 1” vinyl tube
• Cut vinyl below tee so water condensate drains out of pipe
• Slope all pipes to trap so water never drains into gas bag

Fittings to Pump

Using small pump with ⅜” fitting requires specific connections

• Use ⅜” vinyl tubing
• Use ½” barb of the strainer to connect vinyl tubing
• Other end of strainer is NPSM
• Epoxy in a ½” NPTM to PEX
• Do not use the NPSM fitting
• The standard NPTS-M to barb is a rare fitting, should be avoided here
• Use heat gu to expand tubing if needed

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Remaining Design

Heating Detail

• Use manifolds for connections

Automation

• Controls
• Electrical - 12V to macerator pump (use 24V macerator pump next time) + 24V lines

Gas Bag Structure + Plumbing

1. daf

Enclosure Detail

1. d

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