Diagram posted in only for understand how principle work, you need to add some stage for filter KOH (if you use that), flashback arrestor, mixing chambre,etc..
I advise you about brown gas, first of all need to filter gas from electrolyte and water vapour because you can create poison gas very dangerous for life. Second if you use brown gas as additive for your engine you destroy your engine, the time of destruction depend only from the quantity of brown gas that you sent inside.. more brown gas and you destroy your engine fasctly. I have been tested that some time ago on special engine.. main problem is the oil mixed with water that creates an product similar to soap and accelerates the formation of rust on bearings and gears. All brown gas cells actually in commerce are very dangerous for your engine and your wallet. Micronic gas is the only solution. Regards Alessandro