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CHEMICAL PROCESS INDUSTRIES Limestone is being calcined in a rotary kiln with coke breeze

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CHEMICAL PROCESS INDUSTRIES Limestone is being calcined in a rotary kiln with coke breeze.  The flue gas contains 31.3 % CO₂, 1.8 % O₂and no CO or H₂.  The analysis of the stone is 51.0 % CaO, 2.0 % MgO, 42.2 % CO₂, 1.5 % Al₂O₃, 1.2 % SiO₂ and 2.1 % H₂O.  The coke is hydrogen free and dry and contains 8 % ash.  Calculate the The fresh feed to the process contains nitrogen, hydrogen, and 0.4 mole% inerts. The nitrogen and hydrogen used in the reactor is in the ratio 1:3. The reactor effluent passes to an absorber that removes part of the ammonia and none of the reactants or inerts. The unused reactants, inerts and unabsorbed NH₃ are recycled to the reactor. To avoid buildup of the inerts in the system, a purge stream is withdrawn from the recycle. The recycled stream contains 4 % NH₃ and 4 % inerts.

Calculate the NH₃ recovered and the amount of purged stream per 100 moles of 

fresh feed gas.     

      What is the overall conversion?

      What is the single pass conversion if the recycle to fresh feed ratio is 10?