Basics

This page aims to go over the “Why, When, and How” a Biodigester would need to be Decommissioned
This is as a part of Design for Decommissioning / Cradle-to-Grave / Product Lifecycle Management etc

Why

Nothing lasts forever, so EVENTUALLY some components will fail
For some, such as a Macerator Pump etc, or some Biofouling , this will be a matter of (Preventative ) Biodigester Maintenance
Large Accumulation of Sludge / Digestate Precipitate and/or Leaks forming in the IBC Tote (or other “main” container) COULD BE solved via a small scale equivalent of Shutdown Work and “bandaid fixes” such as Cleaning then Lining the tank (in a manner akin to Cured-In-Place-Pipelining ) or converting the tank to a smaller PVC Tank Liner system (or equivalent) ARE POSSIBLE but are similarly expensive for a less “complete” fix, and often introduce their own problems/risks
This, combined with eventual Moves/Changes in Desires/Demolition etc EVENTUALLY means that a Full Decommissioning (or at least Demolition to Slab then Rebuild will be needed

When Major Components, such as the IBC Tote are reaching the end of their Service Life
- As per the principles of Preventative Maintenance , as well as the costs of Emergency Response work (in that a Plumber or additional help when you can afford to “shop around” vs when your house is flooding with Blackwater etc, there is an advantage in swapping a tank SLIGHTLY before it’s EOSL date, despite there being SOME waste in this.
Forming a Decision Making Matrix type Biodigester Routine Inspection Checklist + Having an Inspection Schedule (+ Potential Routine PM) would be worthwhile
- While WAY less easy, especially in tough times, having a gradually Saved Up Fund, or some sort of non-crappy decentralized insurance / Biodigester as a Service plan is advisable (Depending on the cost of the whole endeavor
- Depending on the Product Lifespan / Service Life of the biodigester, this may become an issue of Intergenerational Wealth / Intergenerational Debt/Liability too wherein for the Parent who buys it, it works great, but upon their death the kids ALSO have to clean up a Dry Rotted IBC Tote leaking Blackwater in their house (before selling it or something etc) which is something noone would want to be dealing with then

RE Biodigester Shutdown BUT
All power going to it will be Lock Out Tag Out shut off at minimum, “Air Gapping” / “ Isolated “ is preferable
- Although IN THE PROCESS of Airgapping/“Frying Pan”-ing off stuff, work under LOTO will need to be done
Once all the Hazardous Energy (Mainly electrical, although leaking Water/Greywater is a low risk but related concept) (Residual Biogas is a related concern, and Fuel Tank Inerting / HEAVY rinsedown with water/soap or Degreaser is advisable pre-doing any work
- Much of this would be pending a Site Specific Job Hazard Analysis and a Tailgate Safety Meeting with the whole crew (Although Templates/MOST of the points could be made and put on this page in advance)

This could be done via Gravity Drainage, although a Macerator Pump (potentially the built in one, although a “Decomissioning Cart” / Skid Mount type thing may be nice too) or Vac Truck is preferable
Attaching A Cam Lock fitting (2in or up) to the Biodigester would aid in this
IBC Totes CAN be rinsed out, but a Cone Bottom Tank woild be especially useful for this as well
Trying to Pump Out Before Rinsing can reduce volume of Industrial Wastewater (although depending on content/regulation compliance issues etc this could MAYBE be pumped into another Biodigester system, in a manner to RV Pumpouts via Macerator Pump into Municipal (Home) Sewer
- HOWEVER if sludge/precipitate is especially thick, using a Pressure Washer or Chicago Hose to “get it going” / liquify things may be required
- Tank Materials / Tank Linings and Routine Maintenance will reduce this difficulty however

It is difficult to clean what one cannot see or access
A Clean in Place Tool such as a “Gamma Jet” can work, although as of now these are rather pricey, and similarly require high PSI/GPM Pressure Washers
- Furthermore some do not “like” Hot Water from Hot Water Pressure Washers which MAY be of use otherwise
Either way suction/pumping is kept on, and the tank is Rinsed (with optional occasional spray of Degreaser / Soap / Solvents etc) until it is considered “Clean”
- How Clean is Clean is another important consideration, worth putting down in Paperwork+Communicating to ALL workers
- In the case of Decommissioning however “ Demolition Clean “ / “ Scrap Clean “ / “ [[DOG Transportable Clean” is probably all that is required
- To what degree the debris will get “stuck” in the plastic like Pasta Sauce in Clear Plastic Leftover Bins is another bit to consider

Final Assemblies can be Dissasmbled
Larger Objects can be transported via a Flatbed Truck / Low Bow Truck / Lift Gate / Box Truck]]
Another option would be more conventional dumpsters / Roll Off Boxes
While it isn’t great for reuse/recycling, using a Reciprocating Saw (Sawzall) or Oscillating Tool (“Multitool”), may be necessary to make larger components into workable pieces
Cleanup of any Splatter, as well as “hidden dust” with a Broom/Dustpan then Vacuum and/or Mop etc is also advisable vs “rip it out and run”