I'm posting some replies in hopes that someone reciprocate.  In a normal low temp, refrigerated gas plant, the MEG is set to around 78%, or 1.082 SP.  If you look at a freeze point curve of MEG, you will quickly see that between 70 and 80% is the lowest freeze point.  The rate is approximately 1/2 gpm per 1MMCF.  The reboiler temp is what controls the MEG concentration and a good starting point is 240F on a 0 PSI reboiler.  It goes up from there if pressure is increased on the reboiler.  The glycol is delivered to injector nozzles that are located at the rich gas inlet and usually half way through the refrigerated exchanger, spraying through the nozzles creates an atomized mist that readily mixes with the gas stream and as the gas is liquified, stays with the liquids and ends up in the cold separator with the NGL in an emulsion.  Most of these plants have a gasoline / glycol separator that allows the glycol some resident time to fall down to the bottom of the vessel, then a level controller sends it back to be heated again, driving off the water as vapor and bringing the glycol back to the right percentage.  I like the milton Roy diaphram pumps because they are very reliable, some people use gear pumps because they produce a steady stream, but they always break down.  The pulsation of the diaphram pump is not a problem.  I can tell you much more from real life experience if you want.  Good luck