Sure, I do hope that those scientists are not totally irresponsible. Still another heat exchanger will further lower the efficiency of the system. In my experi

Sure, I do hope that those scientists are not totally irresponsible. Still another heat exchanger will further lower the efficiency of the system. In my experience (maybe a tad bit dated) common heat exchangers (water/water) are difficult to maintain as - generally speaking - the most efficient ones have smaller passages for the liquid and they tend to become clogged and it is "normal" to clean them periodically. I have no idea how large must be a heat exchanger (where one of the fluids is lye) to be efficient enough, considering also that the temperature is relatively low, but most probably it won't be exactly "compact".