Section XXXXXXXXXXstates that 14 MMscfd (0.4 × 106 Nm3/d) of dehydrated gas is used to regenerate the molecular sieve beds. Assume that sales gas (see Table 20.1 for composition) fires the...

Section 20.2.4 states that 14 MMscfd (0.4 × 106 Nm3/d) of dehydrated gas is used to regenerate the molecular sieve beds. Assume that sales gas (see Table 20.1 for composition) fires the regeneration furnace. Using the assumptions below a. Estimate how much sales gas (Mscf, Nm3 ) would be consumed in one bed regeneration. b. Estimate energy consumed (Btu, MJ) by furnace and regeneration compressor in one bed regeneration. Assumptions: 1. The furnace is 80% efficient (LHV basis), runs for 6 h in regeneration, and heats gas from 80°F (27°C) to 500°F (260°C). The average CP is 0.66 Btu/lbm-°F (2.76 kJ/kg-°C) for the gas in the regeneration furnace. 2. Cool regeneration gas runs through the bed for 2 h. 3. Regeneration gas leaves bed at 800 psig (55.2 barg) during heating and cooling steps. The gas enters the recycle compressor at 80°F (27°C) and the discharge pressure is 850 psig (58.6 barg). Use γ = 1.25 for compressor calculations. Overall adiabatic compressor efficiency is 76% (includes driver and compressor).