The treated salt brine is subjected to concentration (boiling-down), crystallization and separating the crystalline salt from the residual solution in the salt-works apparatus.
The salt-works is designed to make maximum use of all energies produced by the energy generating node.
Two evaporators are proposed – one evaporator (EV 1) functions on the thermo-compression principle and the other evaporator (EV 2) is vacuum-based with use of steam and heated cooling water from the energy generating node.
The introduced raw material for the EV 1 evaporator is treated salt brine pre-heated in heat exchangers VW1, VW 2 and VW 3. The solution boils-down in the evaporator and consequently salt crystals are expelled.
The heat used for water evaporation is supplied into the EV 1 evaporator by the HK 1 heating chamber through which the solution/suspension circulates with help of circulation pump P 01 through the circulation pipeline UL 1. The HK 1 heating chamber is heated up by compressed waste steam from the EV 1 evaporator – thermo-compression principle. The waste steam from EV 1 evaporator is sucked by two parallel lined centrifugal compressors TK 1 A, B after it has been de-salted in the BW 1 washer.
The compressed and heated waste steam is cooled down by condensate spraying in the EH aftercooler (final condenser) and are conducted into the HK 1 heating chamber. The condensate from HK 1 is used mainly as percolating water in drill-holes. Crystal kitchen salt is evacuated from the evaporator through an inter-reservoir and hydro-cyclones into two pulse filtrating centrifuges ZE 1 A,B. The filtration cake, salt with humidity content below 3% wt is transported into salt storage; from there it is transported (after adding anti-fusibles) straight to expedition as so called wet industrial salt. One centrifuge is capable of working short-term with up to double load with centrifuged salt humidity increase up to 6% wt.
EV 2 evaporator introduced raw material is the residual solution from the EV 1 evaporator.
The water evaporating heat for the EV 2 is supplied by HK 2 heating chamber, through which the solution/suspension circulates with help of circulation pump P 10 through the circulation pipeline UL 2. The heating chamber HK 2 is heated up by a part of waste steam from the EV 2 evaporator which is sucked from the evaporator by a steam ejector EJ which also creates necessary vacuum in the evaporator. Mix of waste steam and straight water steam (after the ejector) is used to heat up the HK 2 heating chamber. The HK 2 condensate is used as percolating water in drill-holes. Into the ejector also the condensate is conducted, which is heated up in the WT exchanger by the cooling water heated in the energy generating node.
The rest of the waste steam is sucked from the EV 2 evaporator by water-circulating air-pumps VP 1 A,B through pre-heaters VWO 1 and VWO 2 (in one of them the raw salt brine is pre-heated on its way to chemical treatment and in the other the treated salt brine is injected into the EV 1 evaporator) and through the KO mixing condenser. The waste steam condensate from VWO 1, VWO 2 and KO is after-cooled in the cooling tower KT 1,2 and is used as a clog and cooling water and for showering in the KO mixing condenser.
The crystalized kitchen salt is evacuated from the evaporator through a inter-reservoit and hydro-cyclone into a pulse filtrating centrifuge ZE 2. The filtration cake, salt with humidity content below 3% wt is transported into salt storage; from there it is transported (after adding anti-fusibles) straight to expedition as so called wet sprinkle salt.
The centrifuge filtrate and EV 1 and EV 2 evaporator blow-down are subject to chemical treatment together with raw salt-water.
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