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Politecnico di Milano School of Industrial Engineering Course Energy Systems proff. S. Consonni, E. Martelli, M. Romano - Academic Year 2019-20 Energy Systems LM – written test of 08 September 2020 page 1 o f 3 Written Exam of 8 September 2020 - Problems - Time: 2 hours PLEASE NOTICE 1) Exam is open book, but computers and cell phones are NOT allowed. Talking with colleagues and/or copying will lead to the immediate cancellation of the exam. 2) Answer clearly ONLY to the questions posed by the problem se ts. Even if correct, additional considerations and/or calculations will NOT be considered. 3) Fill this sheet with your name and return it together with your solutions. 4) Mark each sheet of the solution with your name and page number. 5) In addition to the points obtained for the solution of each problem, a bonus of max 3 points may be given based on whether the solution of each problem is complete, with clear details and explanations. Problem data depend on your person code according to the following two variables: X = sum of the numbers of your person code Y = sum of the first 4 numbers * sum of the last 4 numbers of your person code So, for instance, if the person code is 12345678  X = 36  Y = 10*26 = 260 INDICATE ON THE FIRST PAGE THE VALUES OF X AND Y DERIVING FROM YOUR PERSON CODE THAT YOU WILL USE IN THE EXAM Problem 1 (10 points, including Q1) A boiler for producing steam is fed with a gaseous fuel with the following molar composition:  72% methane (CH4: MM=16 kg/kmol, LHV=50 MJ/kg);  X/5% carbon monoxide (CO: MM=28 kg/kmol, LHV=10 MJ/kg);  remaining fraction is CO2 (MM=44 kg/kmol). Assuming that air composition is simply 79%N 2, 21%O 2 and knowing that the molar concentration of oxygen in wet flue gases is 5%, determine: a) The LHV of the gas fuel (1…