At the brewery the Mash Tun and Brew Kettle were combined, here the Mash and Lauter Tun are combined together and rather than use an electrically powered RIM heating device, which circulates the liquid portion of the mash along a heating element, the CHEM system circulates the mash liquor through a copper heat exchanger coil located in the Hot Liquor (hot water) tank.
CHEM is built from three used half barrel kegs I purchased. All the plumbing is half inch copper tubing which is built into a 2x4 wood frame with a laminated kitchen counter top.
There are two self igniting, dual ring, adjustable, 45,000 BTU propane fired burners. One is under the Hot Liquor Tank located on the left end of the system and the other burner is under the Brew Kettle to the right of the system. The Mash/Lauter Tun combo is positioned between them. Each burner sits on a 3/8 inch thick, 18 inch square ceramic tile to protect the counter from the reflected heat of the burners.
A grain hopper and mill can be attached directly above the Mash/Lauter Tun allowing the grain to be milled directly into the Mash Tun for dough in. A removable variable speed agitator can be seen mounted in place on the MLT.
There are still a couple minor items to do to complete the system such as a sight glass, or a manometer, for the Mash/Lauter Tun, to show the liquid level during lautering. Originally each kettle was going to be wrapped with insulation and a sheet metal jacket but having used them during the Winter the plan has been dropped as there was no noticeable temperature drops.
Check out the "Images" links below for additional pics of the CHEM system.