Boiler extraction

Sugarcane is an important commercial crop worldwide. Not just for the sweet, white granules we all consume far too much of, it is also a principal source of ethanol, bioelectricity and animal fodder, as well as several chemical composites. Sugarcane is, in fact, the world's largest crop by production quantity.

Consequently, sugarcane production is big business worldwide. However, nowhere more so than in Brazil, which accounts for more than 40% of the world total.  Brazil is by far the world’s largest producer of sugar cane derivatives and outperforms its next six closest competitors combined. More than 90 percent of its production output comes from the South-Central region of the country which exports its products to more than 120 countries around the globe. 

Needless to say, the world has a craving for sweets, but as we are warned of the dangers of excess consumption, the sugarcane industry is slowly shifting its focus. More mills will now prioritize ethanol production at the expense of sugar, due to better returns.

After the sugarcane stalks are crushed to extract the juice, the remaining fibrous solids, called bagasse, are burned in the mill's steam boilers. These boilers produce high-pressure steam, which is passed through a turbine to generate electrical energy. So, instead of going to waste, bagasse is used as a biofuel for the production of heat and electricity. Actually, bagasse makes the mills more than energy self-sufficient and surplus electricity can be sold. 

“Due to very aggressive components and high temperatures, it is necessary to do regular maintenance on the tubes of these boilers”, says Managing Director at ENRX Brazil, Rafael Herrero. “And this is where we can help.”

“Basically, they have to change all tube connections on the boilers”, Rafael says. “Traditionally, boiler tube extraction has been done with flame heating, but some companies don’t allow this anymore.”

Apparently, the risk involved in such an operation is too high and, in many cases, results in serious damage to the boiler structure. And certainly, when comparing the state of the boiler after flame extraction and extraction done with induction heating, it is easy to see why many mills prefer the latter.

“The extraction is done by heating the tubes to 1000°C, and then, with help of a mechanical device, the tubes are pulled from the boiler structure”, Rafael explains. To be fair, induction heating is more expensive than flame heating, but Rafael is confident that the many advantages will sweeten the deal considerably.

“Obviously, it is fast, accurate and repeatable – like all induction heating processes”, he says. “There is no need for any re-work on the boiler structure, and that saves both time and money. Most important however, is the safe operation and reduced boiler downtime due to short heating time.”

The Minac 25/40 SM is the equipment of choice for this process. This mobile and versatile frequency converter has a conveniently small footprint, making it very easy to load into a car and transport to the mill, where it can be carried by one man to the tube boiler. All you need is to plug it into the mains and it is ready to go. The Minac can be fitted with a practically limitless range of coils and is operated by one or two handheld transformers, which basically are as easy to use as a regular electric drill.

ENRX Brazil has actually already sold several Minacs for this process to operators in Brazil and Colombia, but the major potential for this business is equipment rental to sub-contractor companies responsible for tube boiler repairs and maintenance.

Of course, at the customer’s request, ENRX will also offer a skilled and experienced operator. Service Technician, Deivid Garcia, has become quite the specialist on this type of work and is ready to take on new assignments.

“By the way, it is worth noting that this type of induction heating process can also be used for paper mills”, Rafael points out. “We have done that type of job several times too. Actually, we have another coming up next week."