There are a lot of options to consider with floor drains in a brewery. Floor drains, trench drains, equipment drains- they all have their place. Since these will be set in concrete, they are a permanent part of your infrastructure and should be installed with durability in mind.
What’s better, lots of floor drains or 1 big trench drain? It all works, so don’t lose sleep over it. The concrete work is more consistently sloped with a trench drain vs lots of different slopes with floor drains. If you have a high forklift traffic area, smooth and consistent is good. Floor drains are smaller and are generally cheaper and potenially more durable.
With either option, materials include cast iron, brass, plastics, stainless steel, and concrete. Cast iron and brass do not hold up over time in brewery applications due to CIP chemicals and hydrogen sulfide gas. Plastics are not durable enough. In a high use application you could expect about 10 yrs out of a cast iron floor drain. Then you have to dig it up, replace it, repair the concrete, and redo your floor coating. Sounds expensive- and it is. As with most things in a brewery, stainless steel is always better. Pay for it once and it’ll work forever. But as we all know, money is tight when building a brewery and stainless floor drains are usually not a high priority.
Another option that looks good but I have no direct experience with is Slot Drain. Looks great, but I worry about lack of access and wild bacteria and yeast growing on the hidden parts.
An option I have not tried is cast iron with an acid resistant coating, similar to a cast iron kitchen sink. You will see drains like this a lot below commercial dishwashers. JR Smith is a large floor drain manufacturer, they are most often specified by architects. You can see their coated cast iron drains on their sanitary drains page. Again, I have no idea how well they will hold up in time in a brewery. I’d imagine they last longer than uncoated cast iron but a lot less than stainless steel.
Trench Former is a nice product, making the drain part of the slab itself. Even easier is to make a shallow groove in the floor and slope it towards a pipe in the slab. A concrete floor drain would be coated with the same material you use on your floors- urethane but with no traction sand.
A product I recommend avoiding is prefabricated resinous trench drains, lots of different outfits make these things. They break. Drop a keg, set down forklift forks too hard, drop a hose end too hard, you get the idea. Not good. They also suffer from corrosion problems due to chemical and temperature. What happens is a chunk of material breaks off and exposes the aggregate underneath, then water gets underneath and leads to more breaks.
I recommend installing all drains as if a forklift was going to drive over it. Someday it will. Maybe only once or twice during equipment install but durability is important.
Screens in the drain are important. They don’t need to be fancy, but things make their way down the drain. Chunks of pallet wood, TC fittings, spanner wrenches, shrink wrap, etc. Screens can have varying sizes, large holes for high water flow and only to catch the largest particles; smaller holes to catch grain and hop particles. Of course the drains need to be accessible, don’t install them directly under a piece of equipment. What you don’t want to happen is for employees to remove the screens and not replace them because it’s a pain.
Plenty of floor drain clean outs are very handy, even with screens a pipe will plug at some point down the road. Drains will have a trap, not good entry points for a sewer rooter. A cleanout has no trap. Another handy function of the cleanouts is you can put a camera down there for inspection. But the best feature of the camera is you can use a location device to find the camera from above the slab, it will tell location and depth. Of course as-built drawings could show this information but they never do.
Lastly, equipment drains. Not always the most appropriate, but nice to use if you can. This is basically a stainless steel pipe coming out of the slab. Weld in a small funnel to the end of the pipe. Then direct equipment drain pipes or hoses into that funnel (leaving an air gap) and you have a dry, clean floor:
Equipment drains are handy under a bottle filler, keg line, CIP manifolds.
Another way to do an equipment drain is to cast a floor drain into the slab a few inches below finished grade. This would only be done in a no traffic area, but you could have a small section of very steep slope leading right in to the drain. Handy in certain areas (under a brew kettle).
As usual, if you have any questions about this type of stuff please contact me. I can’t cover every little detail in a page like this. Thank you, John