Objectif Scope of the activity is the design, construction, testing, and operation of a desalination plant fed by residual hot sea water coming from the condenser of the power plants cooled with sea water, with the general aim of verify the technical and economical viability of the project with a temperature difference between the hot and cold sea water in a range of about 8 deg. C.The result is a save of 500 TOE/year of energy in the actual configuration :Average yearly production = 13. c.m/hSteam consumption = 1100 kg/h The project was executed as planned and has been completed with a small timedelay. The results were excellent and the calculated simple payback period is very short (1,1 years). The installation has a long expected lifetime caused by good quality of materials used.All the system has been patented with patent number 1227372 Milano/Italy. In general it has been a very successful project with good possibilities in commercialisation.The idea of producing desalinated water at low temperature was originated by the consideration of the huge amount of energy rejected by Power Station through the cooling water.This energy totals more than the net energy produced as electricity, being the efficiency of a Thermal Power Station well below 50%.The low temperature of the cooling water rejected by a Power Station does not allow any recovery at the present state of the art, being such temperature the lowest in accordance with the optimization of the Power Cycle.Any low efficiency recovery, compared with the large amount of energy available, is anyhow convenient. Therefore even a single flash can be proven to be of industrial significant importance. The nominal production duty of the plant is set at 20-30 t/h of distilled water, the production duty of 20 t/h is relevant to a nominal temperature drop of only 8 deg. C; this is also the minimum temperature drop that can be found in a thermal power station. This same plantcould produce larger quantities of distilled water in presence of higher temperature differences.The sea water rejected by the main condensers of the Power Station at the highest temperature level is fed to the vessel of the evaporator in which it partially vaporizes at a temperature of 24.2 deg. C; the evaporated water is fed to a condenser cooled by sea water having an inflowing temperature of 20 deg. C and an outflowing temperature of 22.8 deg. C.The condensed water is collected in the hot well of the condenser and pumped to the user while the residual quantity of sea water which has not vaporized, is discharged from the vessel of the condenser at a temperature of 25.1 deg. C.To keep the required vacuum level in the vessel of the evaporator, it is necessary to purge the air deviled by the sea water, which evolves in saturation conditions; a group of multi-stage ejectors is provided to perform this duty.The vessels of the evaporator and the distillate condenser are realizedin two different shells connected by means of the transfer line of the vapour; both shells rest on proper metallic structures at suitable heights.The lay-out criteria for both plant components are the following :- the bottom of the vessel of the evaporator must be positioned at such a net height above the free surface of the discharge channel as to ensure a gravity downflow of the brine to be drained, overcoming the superimposed back pressure due to the atmospheric pressure and the friction heads of the drain tube itself.- the upper heat exchange tube in the condenser must be positioned at a sufficiently low level to guarantee that the cooling water in the same tube does not vaporize.- the contact-intercondensers of the vacuum group must be positioned at such a height as to ensure the forming of the free liquid surface at a fixed maximum level.The two above mentioned plant components are therefore positioned at two different levels to meet the above listed requirements. Programme(s) ENG-ENDEMO C - Programme (EEC) of demonstration projects and industrial pilot projects (EEC) in the energy field, 1985-1989 Thème(s) 2.1 - ELECTRICITY Appel à propositions Data not available Régime de financement DEM - Demonstration contracts Coordinateur SOWIT SRL Contribution de l’UE Aucune donnée Adresse VIA PIO LA TORRE 14/B 20090 VIMODRONE (MI) Italie Voir sur la carte Coût total Aucune donnée
