Try this link. Go to industries tab for more tank photos.
Tanks
We had their tanks in our fuel blending facility.
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Pat,
The attached photo is pretty good for a "fine chemical" batch plant. It shows 4 stainless steel mixing tanks (the green motor on the slant is the motor for the agitator) and a "manway" opening. It was easy for the operators to add chemicals as required through the manway. However, it also exposes the operator to the contents of the vessel and also allows possible contamination from the surrounding area. You can also see the exhaust hood above the manway opening. Its purpose was to remove fumes and sometimes dust during charging (chemical addition) operations. It is somewhat dated. But, again, there are chemical processing facilities still in operation very similar and I have seen some that are not as nice.
Throughout my career I have designed and then managed/operated chemical plants. Both large petrochemical and then batch chemical and pharmaceutical plants including pilot plant operations (4000 gallon batch reactor trains down to what they call kilo lab scale).
There are several ways of masking taste. Flavoring could actually be a coating around the active ingredient, where the active ingredient would have an objectionable taste. Sometimes this is referred to as Taste Masking. The active drug would normally be a solid (powder) suspended in a slurry/liquid. So you may want to google "blenders". https://www.bplittleford.com/batch-processing.html . Depending on the chemistry, the material would/could be dried (liquid removed).
Check some used chemical equipment sites to get some ideas of what the equipment looks like. As others have recommended, add search for reactors, batch reactors, etc. along with kilo-lab for smaller vessels.
Regarding Dimetappe (brompheniramine and phenylephrine); Here you are dealing with a drug and therefore open operation (open top tanks, open man-ways, etc.) is an issue. The engineers will design in safety for both the drug and for the operator. Closed charging system, HEPA air curtain, etc. are used. A pharmaceutical plant will have suites/room for each vessel to address cross contamination. The floors will be solid. Walls and ceiling will be cleanable. Wall penetrations will be sealed. Sanitary fittings/piping will be used, proper air systems (HEPA) will be needed on possibly both facility air supply and exhaust systems. Air locks may be needed, the list goes on.
So if you want to scale a FDA inspected facility, it it look much different than a "fine chemical" plant facility. And yes, the facility fit and finish between the 60s and now has changed. But there was still a difference even back then.
Have fun with this project. It sounds like a great way to teach others (children) what your dad was able to accomplish.