Sulphur burner

Moodley, M., Bekker, D. J., Pienaar, P. J., and Pillay, R., Replacement of Sulphur Burner with Liquid Sulphur Dioxide System at the Malelane Refinery, Proc. South African Sugar Technologists Association, 71,142-145 (1997). 

Roberts and McDermott, 1911. Report an an original form of sulphur burner for disinfection. U. 8. Publio Health Rpt, March 31, 1911. 

Hydrocarbons increase the amount of water vapour in the sulphur burner, giving acids. Organic sulphides which can spontaneously ignite may be formed in the presence of sulphuric acid. Hydrocarbons in the form of bitumenous compounds necessitate more frequent cleaning of heating surfaces and can block pump ball valves. 

The approximate actual gas outlet temperature of the sulphur burner can be calculated for various SO2 volume concentrations in the combustion gas. 

The practical values of sulphur burner outlet temperatures will be marginally lower because of heat losses from the lagged furnace to the ambient atmosphere. The general rule of thumb is that the outlet temperature corresponds to the vol% SOj in the gas x 100 e.g. 7% SOj gas ex furnace corresponds to a burner outlet temperature of about 700°C. However, it should be remembered that when the process air is preheated (MM, Mazzoni designs) then the exhaust gas temperature will be roughly 10% higher. 

In this case, the sulphur burner is less dependent upon the sulphur melting process. The day or shift-tank can be placed on load cells so that the metering pump for sulphur can be checked by the loss-in-weight principle. 

The horizontal burner consists of a horizontal steel cylinder lined with firebrick and insulating brick. A firebrick chequer is located in the front compartment. Combustion air enters at the end of the burner below the firebrick chequer. The rest of the burner is subdivided into compartments with over-and-under air pass baffles, which help complete the combustion of the vapours. The flow of liquid sulphur and air oppose each other in the chequer. The hot brick work vapourises and ignites the sulphur as it flows down and the combustion of the sulphur vapour is completed in the after compartments. Chemithon supply the horizontal type sulphur burner. 

The hot S02/air gas flows through the stainless steel 316 inner pipe and the ambient cooling air through the mild steel outer pipe. The first part of the hairpin cooler is used to preheat the dried process air before it enters the top of the sulphur burner. The Chemiton SOs/air-ambient cooler is a simple single horizontal hairpin double-tube heat exchanger. 

S02/air leaving the burner will contain traces of "ash" and "dust" stemming from the refractory material lining the sulphur burner. Therefore the cooled S02/air is passed through a hot gas filter before entering the converter tower. 

Molten sulphur must be delivered to the sulphur burner at a constant, desired rate to ensure that the subsequent downstream SOj-in-air concentration and the SO3 organic mole ratio are kept as constant as possible. 

A sulphur ignition system is used in the Ballestra design of sulphur burner. The following safeguards must be incorporated ... 

The temperature of the gases from the sulphur burner should always be recorded continuously and a high-temperature alarm fitted. 

There should also be prepared a mechanical/instrumental catalogue, containing specific drawings and/or data about plant items like compressors, chiller unit, dosing pumps, transfer pumps, main equipment items like sulphur burner, converter tower, drying equipment, reactors, mixers, etc. etc., instruments and control system. 

Sulphur melting and refining Air drying equipment Sulphur burners... 

Sulphur burning plant and SO2 to SO3 conversion plant block diagram Air drying equipment Sulphur burner... 

A good example where process intensification has the potential to transform a complete plant operation centres on the manufacture of sulphuric add. This can be seen from a study of the SO3/H2SO4 contact process. In order to appreciate the potential impact this approach could have on a well-estabhshed process, it is worth discussing the flow sheet for the manufacture of sulphuric acid/oleum. A sulphur burner produces SO2 which is then reacted over vanadium pentoxide catalyst at 1 bar to produce gaseous SO3. This is then absorbed in recycling sulphuric acid to give product oleum. As is often the case, the reactor is the heart of the process. 

Developments in design. The sulphur burner is almost invariably a fire-tube boiler, but there is a choice of acid coolers depending on the size of plant for which they are used, the area of the land and capital costs. 

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