I finally came up with a setup to fully automate a cluster of semifluid genertors.
You can run as many modules in parallel as you want. Each module consists of a fluid heat generator heating a fermenter, which has a fluid ejector upgrade configured to throw the biogas back into the heater ( must be directionally configured ). It also contains an ejector upgrade configured to eject in the other direction and is preloaded with 3 universal fluid cells. As long as there are at least 2 empty fluid cells they won't fill up until a full bucket of biogas is stored in the internal buffer, thus giving preference to the fluid ejector keeping the heat generator topped off. On the other side of the fermenter, place an electric sorting machine, followed by the semifluid generator. Under the sorting machine, place an item buffer with an ejector upgrade configured to kick items from the blue side up into the sorting machine. Under the semifluid generator, place a hopper attached to the item buffer to suck empty fluid cells out of the generator and send them back to the sorting machine via the buffer. Configure the sorting machine to send full cells to the generator, and empty cells back to the fermenter. Above the fermenter you can place a line of fluid distributors to distribute biomass supplied from a canning machine connected to a pump and macerator filled from either a chest/hopper or a crop harvester.
Visual representation from the side:
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B hThe setup can scale to as many generators as you want ( well, *eventually* you will max out the canning machine ). The only down side is that it is somewhat expensive since the sorting machines take plenty of iron and redstone, and the fluid distributors take a ton of iron too, though you can install those later on and just manually top off the biomass. If you set the sorting machine's default direction to the side for all but the last module, all of the fertilizer will collect in the last item buffer for you to take every now and again.
