I strongly agree that efforts to achieve optimal heat distribution in the reformer pays dividends in the long term, especailly if the maldistribution is severe. Our plant has a good performance history in this area. There is much involved, but to your specfic question, we control the fuel gas to each individual burner row, based primarily on the temperature of the process gas on either side of the riser. We will soon add the ability to control the fuel supply to the burners on either side of the riser; currently we only use one control valve per row (11). Our goal is to maintain a delta T on the 2 TIs either side of the riser of no more than 25 degF.  Secondarily, we balance the fuel from row-to-row to strive for uniformity.

Have you experimented with combustion air? We swtiched to a forced draft system many years ago and quickly saw the value of maintaining uniform air flow. We accompish this by throttling all individual burner air dampers to the same (essentially closed, taking the leakage through the damper) position. This affords a fairly uniform upstream pressure on all burners, achieving a balance by adjusting plenum dampers (2 per row) to achieve unifom supply pressure to each row.

Our reformer process outlet temp is controlled automatically, but this does not provide for any improved heat distribution. Good Luck,, feel free to call for any further discussions. 804-541-5295