Hydrogen Energy: Production

A: The number that matters is the doubling of ΔP alongside higher CO. Sulfur kills activity but doesn’t choke flow. Attrition raises ΔP but usually improves apparent conversion early. Carbon fouling does both at once by blocking pores and shifting equilibrium away from H₂.

A: The threshold is membrane ΔP, not vessel MAWP. Relief valves protect steel. They don’t limit the transient pressure differential across a PEM stack, where even a few bar can tear the membrane before any PSV reacts.

A: 2.5 mol/mol is the red line. Below that, carbon risk dominates. More heat accelerates coke. The only move that arrests damage while you fix the valve is to back off feed and get steam back into ratio.

A: The trap is day-to-hour conversion. 8,000 kg/day at 52 kWh/kg equals 416,000 kWh/day. Divide by 24 and you land at about 17.3 MW, before rectifier and compression losses.

A: The hard number is 0.2 ppm CO. That limit exists because platinum anodes lose activity fast. It’s not about steel or adsorption; it’s electrochemistry at the cell face.

A: The boundary is purity holding steady. Aging adsorbent holds less hydrogen per cycle, so you dump more to tail gas. Leaks and low feed pressure usually hit purity first.

A: The critical limit is local O₂/CH₄ ratio. Without the interlock, you create hot spots well above design flame temperature. That attacks refractory fast, long before product specs shift.

A: The unit trap is cm² to m². 1.8 A/cm² equals 18,000 A/m². Multiply by 1.2 m² and then by 400 cells wired in parallel on the DC side, and you land at roughly 86 kA.

A: The number is 200 °C. LT shift is equilibrium-limited above that. Slowing the gas buys conversion back. More heat just pushes equilibrium the wrong way.