A Demonstration of High Temperature MED-TVC Desalination Technology in the Gulf Area

This work focuses on a multiple effect desalination system with thermal vapor compressor (MED-TVC) operating at a top brine temperature (TBT) of 85°C which is significantly above the common operation temperatures of conventional MED-TVC systems, limited to a range below 70°C mainly due to scale risk. Such increase in TBT would enhance the production and system economics. A pilot plant installed at the Desalination Technologies Research Institute (DTRI) of the Saline Water Conversion Corporation (SWCC) in Jubail, Saudi Arabia was operated at the TBT of 85°C over a 5-month test period. Visual inspection of tube bundles after the test, in conjunction with chemical scale analysis showed that scaling was limited to a soft thin film scale, which was easily removed by flushing with water, which confirmed a low fouling potential analyzed from operation data. Techno-economic analysis of the MED-TVC system operating at a TBT of 85°C, indicated up to 34% reduction in steam consumption and up to 16% reduction in the levelized cost of water (LCOW), when compared with a MED-TVC unit operating at a conventional TBT of 65°C. Accordingly, the high temperature MED-TVC systems operating at a TBT of 85°C can be considered as a financially competitive and technologically reliable desalination option for the Gulf area which has challenging seawater characteristics