Why is it that the Burner sludge processor is unlocked from the Steam power trigger tech,
but the actual recipe that it uses isn't unlocked until Fluid handling?

This makes the entire purpose of the Burner sludge processor obsolete, as Fluid handling unlocks the normal electric Sludge processor.

Proposed solution: move the Sludge processing recipe to the Steam power trigger tech.

Hi
Thanks for the feedback, I've done some digging...
It is intended that the main recipe for processing sludge is to make clay. If clay is disabled (in the glass mod) then this recipe is missing.
If you have disabled clay I'd be interested to know why.
The sludge processing recipe was intended as a later bonus.
I'll have a think about a resolution.

Clay is not disabled, and this issue still happens...

Maybe add a new early rudimentary sludge processing recipe that only returns a small amount of minerals, sand, and clay?

Then you should have the "clay from sludge" recipe.
This is intended as the main way of dealing with sludge and the best way to make clay.

I don't have that recipe available to unlock for some reason...

In fact, the Recipe Book mod won't tell me what tech node it comes from...

Maybe the tech node data for that recipe is broken?

Clay from sludge should be unlocked when glass is unlocked. It's possible there is a mod conflict somewhere.
Can you try disabling other mods, check the recipe is available, then enable other mods a few at a time to isolate the conflicting mod.
Do you have any mods that do stuff with glass specifically?

No, your mods are the only ones I have installed that mess with glass.

I just tested disabling all mods except yours, and the clay from sludge recipe still doesn't unlock...

It seems to be an issue with the mod itself, not a mod conflict.

Interesting...
Maybe a combination of my mods I haven't tested. Can you post your modlist?
(There is a file called mod-list.json in your mods folder)
Might be easier to post the file in my discord.

In the test with all others disabled, I only had:

• QuirkyCat Base
• QuirkyCat Machines
• QuirkyCat Recycle
• QuirkyCat Uranium Changes
• QuirkyCat Glass, Sand, and Clay (and other minerals)
• QuirkyCat Boron
• QuirkyCat Useful Wood
• QuirkyCat Duranium

and of course this mod and necessary dependencies (space-age)

oh...
The recipe exists but nor enabled.
Investigating...

Found it, the unlock was in the wrong place. Will be fixed in the next update...

Sweet, can't wait to see it fixed

Fixed and published. The fix is in the glass mod so you will need to update that one.
Thanks again for your feedback, I spotted several other issues while fixing this. :)

No problem, glad I could help!