Cel To install a Mechanical Vapour Recompressor (MVR) using a turbo fan compressor to concentrate fish stickwater for the production of fishmeal and fishoil. Projected energy savings of 80% for this stage in the process, compared to the simple boiling process, represent 848 TOE for the production of 5,310 T of fishmeal per year. Actual savings were 794 TOE.It should be noted that the operation of an MVR plant in a fishmeal factory is a vastly differed proposition to an MVR plant in the dairy industry, where the majority of MVR systems throughout Europe have been installed to date. Milk and whey are reasonably stable substances to handle and there is little diversity in the quality of milk and whey throughout the dairy industry production season.Fish and fish offal is, on the other hand, very variable in type and quality almost daily, between fish which has been caught for some time before arriving at the fishmeal factory and is in a state of degradation and freshly caught fish.All these factors necessitate that the MVR for a fishmeal plant to be flexible with a turn-down range which is considerably greater than dealing with more stable substances such as milk or whey.The MVR plant was installed at the IAWS fishmeal plant at Killybegs. It has a capacity to handle 300 tonnes of raw material every 24 hours and manufacture approximately 2 000 tonnes of fish meal per annum and 3 000 - 4 000 tonnes of fish oil. The MVR plant was in operation for more than 3 900 hours (in 10 months) up to the end of the project and is designed to run for 4 500 hours per annum. As a result of initial monitoring work, it was evident that the design and specification of the MVR plant would have to allow for a varying flow rate. The range of various components was found to be: Flow rates 6 - 18 m3/hr temperature 75 deg. C - 90 deg. C Solids 6 - 11 % TS Viscocity 40 cp - 400 cp at 40 % TSAs a direct result of the variable feedstock, a number of operating difficulties were encountered and these included tube fouling, blocking of distributor plate holes and the need for frequent extensive cleaning of the MVR. All of these difficulties have been successfully resolved through modification and the plant operates very efficiently on the variable feedstock. The plant has also met all the required environmental standards, particularly those relating to the discharge of organic rich effluents directly to water courses. Although the project has been a technical success, the economic viability of the project has suffered due to the recent falls in fuel oil prices. The recent decrease in oil price has resulted in a consequent decrease in the price of conventional steam generation. It was initially envisaged that a payback period of 3-7 years (1985) would be achieved. In the light of the above, this did not been revised to between 6 and 7 years. On the basis of current heavy fuel of prices, the fuel cost saving is estimated to be IRL54,000 per annum.The project did not realise the expected saving of 848 tonnes of oil equivalent per annum. The actual figure was 794 TOE.The MVR replaces the steam supply by a conventional burner to the evaporator, normally used for the concentration phase.The concentration of the product takes place as follows: preheating in a plate heat exchanger, preheating in a coil, concentration in the evaporator fron 7 % to 40 % TS. The evaporator is equipped with two "one through" passes and three recirculation passes and an existing waste heat evaporator. The solution to be concentrated (fish stickwater) enters at the top of the evaporator and is distributed on the inside of the exchanger tubes where evaporation takes place. The vapour from the boiling solution, separated from the outgoing product at the bottom of a single effect evaporator, is sucked into the double turbo fan compressor. There, the vapour is recompressed and its temperature is raised to that of the original steam entering the exchanger. This steam replaces almost all of the external steam input used by the heat exchanger of the evaporator. In this way, all the latent heat of the product vapour is reclaimed and used to evaporate fresh incinerating plant. The vapour is recompressed by an electronically powered turbine compressor.The stickwater feed rate to the waste heat evaporator is 6-18 t/h at 7 % TS. After the waste heat evaporator, the product is then fed to the MVR evaporator at feed rate of 4 t/h (9.3 % TS) ... 15.5 t/h (8.1 % TS). The product is concentrated to 40 % TS. The evaporator for the above purpose has one calandria equipped with one fan. The boiling temperature varies between 60 and 80 deg. C. The evaporating water capacity is 3-12 t/h. Program(-y) ENG-ENALT 2C - Programme (EEC) of demonstration projects relating to the exploitation of alternative energy sources and to energy saving and the substitution of hydrocarbons, 1983-1985 Temat(-y) 3.5 - AGRICULTURE Zaproszenie do składania wniosków Data not available System finansowania DEM - Demonstration contracts Koordynator IRISH AGRICULTURAL WHOLESALE SOC. LTD Wkład UE Brak danych Adres 151/156 THOMAS STREET 8 Dublin Irlandia Zobacz na mapie Koszt całkowity Brak danych
