The Impact Fuel Tips Have on Industrial Burner Performance - Lindberg Process Equipment

Burner tips are an essential part of proper industrial burner performance as they are used to control the fuel injection into the burner. Available fuel pressure is utilized to distribute fuel evenly into the airstream, so proper mixing is achieved. If burner tips aren’t functioning correctly, safety, thermal efficiency, pollution emissions, and all-around operability are drastically affected. If you’re experiencing issues with industrial burner performance, it’s likely related to the burner tips. Each component of an industrial burner is explicitly designed for that specific burner to allow for certain flame characteristics and overall burner performance. If burner tips aren’t correctly installed, maintained, and designed, burner operation will suffer.

The Effects of Industrial Burner Tips Sizing and Fuel Capacity

Each burner design has fuel capacity curves that are generated specifically for that style and fuel composition. Most industrial burners utilize multiple fuel compositions and curves. Each curve design is created with three factors in mind, the number of tips, hole size, and flow coefficient. A flowmeter is used to measure the total fuel flow in an industrial heater. The burners inside a heater are designed to fire at the same rate, and it’s encouraged to measure each burner’s firing rate. The firing rate can be determined by dividing the heater’s total firing rate by the number of burners present. The actual fuel pressure can be compared to the predicted fuel pressure to identify the correct firing rate and fuel capacity curve.

It’s essential to confirm that the correct burner tips are installed in the burner to allow for accurate readings and diagnosis. The tips are likely plugged if the actual fuel pressure is higher than what is predicted by the capacity curves. Additionally, if the tips have been ordered or corroded from contaminants in the fuel or cleaned repeatedly, holes in the tips will increase in size, meaning the fuel pressure will read lower than predicted. Fuel tips are made of a higher temperature metal alloy because this helps protect them against direct heat exposure inside a heater and minimize metal scaling.

Low NOx burners place tips outside the refractory tile to protect the inner metal components. While this is beneficial to minimize NOx emissions and stage fuel, the tips are exposed to higher temperatures, which can cause issues in some instances, such as low firing rates or tips not having an opportunity to cool before the burners are turned off. If the tips aren’t allowed to cool, they can become overheated, resulting in a variety of issues and eventually plugged holes.

Prevalent Industrial Burner Tip Issues

It’s vital to maintain and care for industrial burner tips properly. If burner tips are not adequately designed, installed, or maintained correctly, many problems can occur:

  • Improper heat transfer
  • Difficulty lighting burners
  • Flame-to-flame interaction
  • High pollution emissions
  • Flame impingement on process tubes
  • Unstable flames or flame pulsations

Installing Industrial Burner Tips

Proper installation of burner tips is a vital component of the performance of burners. The instructions included by the manufacturer provide dimensions and information on how to locate the fuel tips, the direction in which they should point, and proper elevation when in the burner. Instructions vary by each burner, and it’s very seldom that burners have the same installation requirements. There have been instances where the incorrect tips are installed due to burner tip bodies not being stored separately. Therefore, it’s encouraged to organize the burner tip bodies and correctly label, so you’re aware of what parts are designated for each burner. Instructions and drawings should always be utilized in burner tip installation, or more significant problems could occur, such as flame instability, light-off difficulties, and flame impingement.

Proper Maintenance of Industrial Burner Tips

Burners and the heaters they’re located in won’t function properly if the tips aren’t maintained and serviced regularly. It’s crucial to be aware of contaminants present in the fuel and how fuel filtration works. For optimal functioning, it’s encouraged to clean the fuel tips on a regular schedule and to look for signs of the tips being clogged or holes changing in size.

  1. Tips and burners are cleaned at the same time. The tips and burners inside a heater must be cleaned at the same time. Only servicing the parts that appear dirty will result in more fuel flow to the cleaned parts and less to the uncleaned, which leads to the production of asymmetrical flames and operational issues.
  2. Knowledge and use of proper cleaning techniques. Industrial burner tips must be cleaned correctly to allow for proper functioning. Identify the appropriate size drill bits used to make the ports from the burner drawing and cool the tips before removing them.
  3. Burner hole maintenance. Insert and turn the drill bits in the burner holes to remove any contaminants and test the hole size with the next size up. If the new drill bit easily fits in the burner hole, it’s recommended to replace the burner tip. If proper adjustments aren’t made for larger burner holes, burner operation can be affected, and fuel capacity curves, as well as the burner’s firing rate, will no longer be accurate.
  4. Reassembly. After maintenance needs have been met, the tips should be reinstalled on the risers with a high-temperature anti-seize thread compound. This compound will make for a more straightforward removal process in the future. Additionally, be cautious not to overtighten the tips as this could lead to damage and improper tip elevation in the burner.

Industrial Burner Tips Play a Critical Role

Burner tips must perform correctly to allow for accurate burner and heater operation. When maintaining industrial burner tips, you must verify the proper design, installation, and maintenance to ensure the correct functioning and avoid any potential problems. It’s encouraged to utilize the instructions provided by the manufacturer to ensure proper installation occurs. Fuel filtration is beneficial to consider if you’re unaware of how clean the fuel is. Additionally, if you discover plugged tips, they should be cleaned with the designated drill bit sizes provided in the instructions, and any tips with enlarged holes must be replaced. If industrial burner tips aren’t properly maintained and cared for, it can lead to much more significant, dangerous, and costly issues.