you might want to purchase this ACS publication on pH measurements in MEG + Water to help you.
http://pubs.acs.org/doi/abs/10.1021/ie061305a
I have no personal experience to give you tips.
sorry,
MAeng11
Have you considered a coating or liner for the inside of the pipe? (i.e. teflon or some other epoxy coating to prevent adhesion to the pipe wall). We lined a zirconium reactor with PTFE in order to prevent char build up and plugging and it has worked very well for us. albeit the processes are...
Rees101
I am fairly young in the industry however it has been my experience that in order to get to a magnitude +/- 30% cost estimate some idea of the location of the installation is required. Domestic vs international, region specific usually. So i guess i would need more info in order to help...
