In order to recover the clean condensed water and enable its reuse from the RO rejects and ETP solution we offer Multi effect evaporators. The system is used to reduce the water loss through double or triple Effect Combination Evaporator with one falling film type and one forced circulation type evaporators. The material of construction for all liquid contact parts in SS304 and Calandria tubes of SS304. All vapor and condensate contact parts will be in M.S.
Complete system will be under pressure at 3 kg/cm2( g).and consists of following components :
- Feed Pump : A centrifugal direct driven pump is used for transferring the feed solution from the balance tank to the Calandria. The pump is provided with a single mechanical seal and electrical motor. All contact parts with liquid will be in S.S.304.
- Calandria : This Calandria is essentially a vertical shell and tube type vertical heat exchanger and is designed as per the Falling film /forced circulation principle. Steam is provided on the shell side and feed solutions is passed through tubes. The tubes of Calandria are of 25.4/ 31.75 mm OD. Adequate no. of tubes 4/6 M length are provided for the heat transfer duty. The tubes are welded on the tube sheet. The shell has nozzles for steam/vapor inlet and outlet, and temperature gauge. All Contact parts with liquid will be in S.S.304. Tubes will be of S.S.304. Thermic fluid/Steam and other non-contact parts will be in M.S.
- Vapor Separator : In vapor separator, the heated liquid coming from the Calandria is flashed. Saturated vapors coming out from top are sent to the next Calandria/condenser. Liquid concentrate coming out from bottom is withdrawn as feed to next Calandria/ as product. The separator shell has sight and light glass for viewing the concentrate level. Material of construction for all contact parts with liquid and vapor will be S.S.304 and non-contact parts will be in M.S.
- Re-circulation Pump : This pump is provided for re-circulation of slurry inside the heat exchanger, so as to increase the velocity of liquid inside the tubes and to get the required heat transfer. This is a Centrifugal Pump with double mechanical seal and motor. Contact parts will be in S.S.304. Concentrate outlet will be taken out from recirculation pump so the discharge head will be at around 5-6 meter only.
Condenser is used to condense the evaporation rate at the outlet of system. It also consist of condensate pot, condensate pump and vacuum pump.