Objective To collect gases previously flared - off and use them to form a mixture with fuel gases from different production units in a cogeneration unit to generate electricity. This will conserve energy and minimise losses caused by power cuts.Normal production began in Nov. 1984. From this date and up to Dec. 1985 systematic measurements were taken and evaluated.The innovative features of the project were responsible for the appearance of two serious technical problems which resulted in the replacement of the rotor unit is Gas Turbine 2 and the replacement of the flame heads.The results and energy savings are shown in the following table : 84/85 INITIAL ESTIMATE- Energy efficiency 75,64 % 75,91 %- Usable energy efficiency 43,95 % 42,63 %- Energy savings at Refinerylevel MTOE/y 9139 8418- Usable energy savings at theRefinery level MTOE/y 36923 37931- Usable energy savings atNational level MTOE/y 36668 37182 The project has been successful and has showed "impressive" results both in the field of energy savings and in economic returns.Real investment costs were 40 % higher than initially estimated and have been mainly attributed to price increases and exchange rate differences.Additional costs in the form of damage repairs were small, about 4,26 % of initial estimated cost.Financial returns were satisfactory. Considering fuel oil and electricity prices and exchange rates of January - June 1986, the project's gross margin was equal to 7,7 million US$ and the payback period equal to approximately 2,3 years.Increases in the capacity of the Fluid Catalytic Cracking (FCC) Unit contributed to a greater quantity of fuel gases being flared -off, and together with frequent power cuts in the Public Power Corporation (PPC) network caused large additional production costs to be incurred by the contractor. To conserve excess energy and minimise losses, the company decided to install a cogeneration plant to cover the greatest part of the refinery's electricity demand by using a mixture of the gases previously flared-off, as an energy source.The main innovative feature of the project is in the concentration of the different gases, their pressure equalisation, regulation of their composition within certain limits to maintain a constant calorific value, and their resulting use as turbine fuel.The gathered gases have a 35 deg. C temperature and 3. 5 Kg/cm2 pressure. Mean molecular weight is 20. 2 to 16. 3. They consist mainly of Propane and Butane in various proportions, ranging (by volume) from100 - 60% Propane and 40% Butane.The gases are led through a liquid trap to a compressor, then a gas liquid phase separator to a second compressor: this leads to a compressed gas accumulator, through which the power plant is fed with fuel gas.Compression increases fuel gas pressure from 3. 5 to 16. 4 Kg/cm2 and finally, the fuel gases are led to the turbines at 95 deg.C and 14. 35 Kg/cm2 pressure.The main installation features are:- Fuel gas compression system and LPG vaporization system* operating pressure 3. 5 Kg/cm2* operating temperature 35 deg. C* molecular weight 20. 2-16-. 3After compression to 16. 4 Kg/cm2 the vaporized LPG has a pressure of 14. 3 Kg/cm2 at 95 deg. C. - Gas turbines and alternators:2 gas turbines and 2 alternators of 11. 5 Mw each at 35 deg.C atmospheric pressure- Waste heat recovery system:High pressure steam production 52 T/hOperating pressure 48 Kg/cm2Operating temperature420 deg. CLow pressure steam production 16 T/hOperating pressure 2. 8 Kg/cm2Operating temperature 138 deg. C Programme(s) 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 Topic(s) 3.2 - INDUSTRY Call for proposal Data not available Funding Scheme DEM - Demonstration contracts Coordinator MOTOR OIL (HELLAS) CORINTH REFINERY SA EU contribution No data Address IRODOU ATIKOU 12A 15124 Marousi Greece See on map Total cost No data