Abstract: A system of interlocks for controlling flow of low temperature process streams in a manufacturing process through a cold box to equipment or piping not specified for such temperatures by opening and closing valves and starting and stopping pumps. At least one interlock affects streams heated in the cold box. At least one interlock affects the streams cooled in the cold box. The interlocks are activated by temperatures of process lines to prevent exposure of equipment and piping to low temperatures while preventing the shutdown of the cold box. An override controller including a predictive failure capability is also provided.

Abstract: A system of interlocks for controlling flow of low temperature process streams in a manufacturing process through a cold box to equipment or piping not specified for such temperatures by opening and closing valves and starting and stopping pumps. At least one interlock affects streams heated in the cold box. At least one interlock affects the streams cooled in the cold box. The interlocks are activated by temperatures of process lines to prevent exposure of equipment and piping to low temperatures while preventing the shutdown of the cold box. An override controller including a predictive failure capability is also provided.

Abstract: A system of interlocks for controlling flow of low temperature process streams in a manufacturing process through a cold box to equipment or piping not specified for such temperatures by opening and closing valves and starting and stopping pumps. At least one interlock affects streams heated in the cold box. At least one interlock affects the streams cooled in the cold box. The interlocks are activated by temperatures of process lines to prevent exposure of equipment and piping to low temperatures while preventing the shutdown of the cold box. An override controller including a predictive failure capability is also provided.

Abstract: A system of interlocks for controlling flow of low temperature process streams in a manufacturing process through a cold box to equipment or piping not specified for such temperatures by opening and closing valves and starting and stopping pumps. At least one interlock affects streams heated in the cold box. At least one interlock affects the streams cooled in the cold box. The interlocks are activated by temperatures of process lines to prevent exposure of equipment and piping to low temperatures while preventing the shutdown of the cold box. An override controller including a predictive failure capability is also provided.

Abstract: A system of interlocks for controlling flow of low temperature process streams in a manufacturing process through a cold box to equipment not specified for such temperatures by opening and closing valves and stopping pumps. At least one interlock affects streams heated in the cold box. At least one interlock affects the streams cooled in the cold box. The interlocks are activated due to temperature determinations of process lines by temperature sensors and automatically send a signal to predetermined controllers depending on the process line with the low temperature in order to prevent exposure of equipment to low temperatures while preventing the shutdown of the cold box.

Abstract: A system of interlocks for controlling flow of low temperature process streams in a manufacturing process through a cold box to equipment not specified for such temperatures by opening and closing valves and stopping pumps. At least one interlock affects streams heated in the cold box. At least one interlock affects the streams cooled in the cold box. The interlocks are activated due to temperature determinations of process lines by temperature sensors and automatically send a signal to predetermined controllers depending on the process line with the low temperature in order to prevent exposure of equipment to low temperatures while preventing the shutdown of the cold box.

Abstract: An apparatus and method is presented for reducing mono nitrogen oxide emissions in a hydrocarbon processing furnace. A preferred embodiment hydrocarbon cracking furnace includes a firebox with a set of wall burners and a set of floor burners, the floor burners comprising secondary burner tips burning a fuel-rich mixture and positioned below primary burner tips burning a fuel-lean mixture. A portion of flue gases are recirculated from the primary burner combustion area to the secondary burner combustion area and back to the primary burner combustion area. The floor burners further comprise a set of steam injection ports that inject steam into a conical flow to contact flames at the primary burner tips, reducing flame temperature and thereby reducing thermal NOx. The steam injection ports are positioned in the firebox above the primary burner tips.