A world-class steam cracker has a production capacity of over 700,000 tons of ethylene per year. It transforms naphtha and other refining feedstocks into olefins by cracking the molecules at high temperatures.

The olefins obtained will mainly be used by the companies present on site. The latter will transform them into raw materials for the production of everyday objects such as bottles, packaging, toys, detergents, and automotive equipment.

The Challenge – Steam Superheat Reduction

The plant was experiencing periods of operation with an excessive reduction in steam superheat resulting from inefficient heat transfer in the convection sections. A serious consequence was the excessive moisture formation in the turbine causing water erosion of blades, nozzle partitions, diaphragm throat surfaces, etc.

It is vital to keep the convection sections in steam cracking furnaces in a clean condition, not only for the sake of energy efficiency, fuel savings, and CO2 emission reduction but safe turbine and cracked gas compressor operation.

To ensure optimum performance and production capabilities, regular maintenance is essential, especially for the convection sections of the cracking furnaces.

In use, at the high temperatures required by the process, finned convection section tubes become fouled by dust generated by the gradual deterioration of radiant section refractories.

Historically, in 2015 and 2018, traditional water cleaning – allowing water to cascade over the convection section tubes from top to bottom – had been unsuccessful, showing no signs of improved heat transfer.