Fired heaters with process pre-heat have the greatest running cost on your site. If any one of these heaters is 1 or 2% inefficient it can consume an additional $1m in fuel over a year or result in $millions in lost revenue.
Tube Tech – Engineered Convection Section Cleaning
Hot-tek™ – Online Maintenance & Emergency Services:
High-Emissivity Ceramic Coatings for Process Tubes and Refractory
Cetek Ceramic Coatings provide a durable, protective, thin-film layer on the outer surfaces of process tubes, which prevents oxidation, corrosion, and carburization of the metal and maintains the tube thermal conductivity coefficient close to new tube conditions. Tube coating can be applied in conjunction with a high emissivity refractory coating, increasing the benefit and encapsulating the refractory.
Corrosion and carburization result in metal loss and reduced service life
Radiant tubes in these types of fired heater applications in oil refineries are typically steel alloy, ASTM A335 P22, P5, or P9 which contain 2.25%, 5% and 9% Cr respectively. Radiant tubes oxidize at operating temperatures and scale will grow continuously on the surface, often reaching 2mm in thickness in higher temperature / high heat flux units.
The layers of oxide scale are highly insulating and represent a significant barrier to conductive heat transfer to the process fluids. During fired heater operation, to overcome the insulating effects of the oxide and scale layers, it is necessary to increase the firing rate, to maintain the heat flux through to the process feed inside the tubes.
Cetek’s High Emissivity Ceramic Coating system ensures maximum conductive heat transfer for the process.
Layers of fouling and scale prevent accurate determination of tube metal temperature, reducing the reliability of those measurements. Cetek applies a thin layer of ceramic coating which provides a consistent temperature differential between the outside surface and the metal tube. This results in a significant improvement in the reliability of tube metal temperature determination.
Engineered Convection Section Cleaning
Tube Tech’s Fired Heaters with Process Pre-heat convection section cleaning service is recognised by world-leading refining and petrochemical companies as the most effective technology to achieve OEM performance clean fired heaters.
95% clean guarantee even on the most fouled assets
Fired heater fouling is a costly problem for refineries around the world. Heater intake collects 1 ppm airborne particulate whilst in service, which results in deposits of 2.5 tonnes over 12 months either landing in or travelling through the heater.
These deposits most commonly land:
Tube Tech’s fired heater convection section cleaning service is recognised by world-leading refining and petrochemical companies as the most effective technology to achieve OEM performance clean fired heaters.
Traditional cleaning methods are only able to clean 30-45% of the total fouled area. Tube Tech, backed by multi-million-dollar European funding, has developed a Rover system that penetrates deep between tube rows to remove even the most stubborn fouling.
Read: ‘Tube Tech Restores Convection Section at Petrochemical Plant in Bangkok’
Online Maintenance & Emergency Services (During the Heater’s Normal Operation)
Hot-tek™ is the industry leader in hot maintenance and online fired heater repair and cleaning techniques and holds multiple patents on the approach, methods, and tools used to carry out these services. The approach is customized for every client’s needs. Often, multiple Hot-tek™ Services are employed simultaneously during an application to achieve the best results.
Failure of refractory material can lead to energy wastage, poor performance and even complete shutdown of your fired heater.
Hot Refractory Repair Services may be made gaining access through the heater steel shell directly behind the damaged area. Minimal openings are used to insert specially designed components to support the repair material. This technique offers a semi-permanent repair method lasting at least until the next planned turnaround.
An increase in Bridgewall temperature can be a symptom of excessive fouling of the fired heater’s radiant tubes. These tubes tend to oxidize under operating conditions. Layers of scale and soot can grow with time to a degree that it insulates the tube fireside from the radiant heat. It is even more dangerous if there are several years until the next scheduled shutdown.
Our patented Hot Tube Descaling service removes radiant section process tube fireside soot, scale, and fouling during furnace operation. The process uses unique water-cooled lances and cleans the tubes while the heater continues to function normally. The process utilizes consumable abrasive media resulting in no increase in emissions.
In some applications, we use Cetek’s LancescopeTM system to view hard to reach areas. We also have the capability to safely create engineered access ports. These ports can be used to facilitate the hot tube defouling process.
Occasionally, tube supports (wall and roof) in the radiant section of process heaters fail, allowing the process tubes to potentially become misaligned (sagging or bowing) or even worse, rupture. This can cause significant disruption to productivity and can result in costly unplanned shutdowns.
Hot-tek has developed an online repair service to stabilize the process tubes while the heater is in full operation. Our service can prevent shutdowns and allows the operator to run the unit until the planned turnaround dates.
Low steam production, low process pre-heat, and high stack temperatures are some of the symptoms of fouled tubes within a convection section.
Fouling results in:
Hot Convection Cleaning process removes convection section tube fouling & scale during furnace operation. The tube cleaning process uses consumable abrasive media projected through specially designed application lances to blast away years of accumulation, while the heater is in service.
This emergency or intermediary solution prevents losses associated with taking the heater offline. However, we advise a Planned Preventative Maintenance (PPM) approach, and our Tube Tech service provides industry-leading offline cleaning services to prevent emergency cleaning situations.
Sometimes, an issue can arise in high temperature fixed equipment, but you can’t see the cause or the exact location of the problem. We designed and developed Cetek’s Lancescope™ heater inspection tool for just this situation. It allows a high-temperature furnace inspection to be carried out to determine the scope of the problem, often avoiding an expensive shut down of the heater.
Cetek’s Lancescope™ system provides real-time, close-up, or wide-angle views of virtually any area inside a fired heater, or other high-temperature equipment while it is still in operation.
The hot inspection service for fired heaters uses a state-of-the-art digital camera system, which provides clear, detailed images of problem areas up to 3000°F (1650°C). The furnace inspection system can be inserted into openings as small as 2.75” (7cm) and reach up to 30ft (10m). In applications below 1000°F (540°C), the heater inspection system provides illumination via a high-temperature light source for optimum clarity.
Thorough inspection provides data needed for other Hot-tek online services.
IGS is here to provide information, answer questions and create an effective solution for your needs.
