Homebrew PCBs

pcb.easy wrote:
> Am I on the right track?
> Can the sludge be reduced even more by drying?
> If so how can it be safely dried?

You are doing conventional heavy metal waste treatment by precipitation 
of metal hydroxides. For such small quantities you best off drying the 
sludge in a open tray and put the powder in a plastic or jar and then 
into the rubbish bin. This is more moral than dumping in the sewage 
system. I find builders lime (non pure calcium hydroxide) as a better 
etchant neutralizer as the resulting sludge is more solid and compact.

I have about 10kg of copper hydroxide accumulated of over the years :(