HIGH TEMPERATURE SOLUTIONS FOR THE POWER INDUSTRY

LOY YANG POWER STATION THERMBOND F6L PRECAST DOOR : CAST IN 2006

INTRODUCING:

1.THERMBOND CHEMICAL BOND REFRACTORIES

FOR RAPID REPAIRS TO EXISTING FIRED REFRACTORY

2.OXISTOP CERAMIC COATINGS FOR BOILER TUBES

3. ELKEM WEAR RESISTANT MATERIALS FOR BURNERS AND IMPACT APPLICATIONS

1. THERMBOND REFRACTORY INTRODUCTION:

• Thermbond refractory products employ a primary binder system which is based on a neutralisation reaction of alkali earth metal oxides with a phosphate compound to form stable salts at ambient temperatures and it is stable up to 2150oC. The exothermic reaction leads to flash setting and bodies with high strengths and abrasion resistance at ambient temperature up to boiler furnace operating temperature and above.

• We are finding the real secret is recognizing there is little risk in using Thermbond refractory for permanent refractory repairs and construction because the behavior of Thermbond products under reducing atmosphere and thermal stress conditions is found to be well advanced of conventional hydraulic bond refractory castable technology and provides valuable operating time that is recovered when using Thermbond refractory technology.

• In one case within a coal fired boiler furnace, the cost of the fuel oil used on start-up when firing in the new refractory burner quarls is more than the premium of Thermbond refractory (this is a coal fired plant that starts on fuel oil until reaching operating temperature at which time they begin to burn coal). Thermbond dry-out is 2 days faster than conventional refractory so they obtain 2 more days of production as well!

• We welcome your enquiries to explain in more detail the savings on dry–out time and fast heat up procedure with out evidence of thermal spalling issues that are currently experienced combustion furnaces and vessels.

• Think of the large savings in refractory turnaround costs that are recovered, the increased life of the Thermbond refractory versus traditional refractory.

LOY YANG POWER STATION REPAIR 2006THERMBOND F6AG GUNNITE CASTABLE OVER FIRED REFRACTORY IN OFF TAKE GAS

MILL DOOR THE REPAIR IS OVER 4 YEARS OLD AS OF DEC 2010

THERMBOND MYTH VERSUS FACT!

Myth : Thermbond is too expensive!

Fact : Whilst the price per kilogram of Thermbond is more expensive than conventional castable, Thermbond actually cost less to use in most applications. When evaluating refractory cost in applications, you must factor in lost production, total downtime, total volume of material used, ongoing refractory maintenance budgets and total refractory life.

Considering the following benefits of Thermbond, it is always the least expensive solution!

• No dry out required, much faster curing (~4hrs) and heat up @ 260 degrees C/hr.

• Ability to permanently repair rather than replace (less volume of material).

• Less maintenance and planned outages.

• Extended refractory life due to excellent physical and chemical properties

Myth : Thermbond liquid Activator is unsafe!

Fact : The liquid activator component of the Thermbond is a mild diluted agricultural grade phosphoric acid solution. Similar phosphoric acid is used in lawns and gardens. Further refinement of phosphoric acid is used in foodstuffs.

The proper material safety data is supplied. Thermbond refractory is as safe as any other refractory material.

Myth : Thermbond is only used for patching!

Fact : Whilst Thermbond provides a permanent, tenacious repair to existing fired refractory and itself, Thermbond is also the choice for full thickness linings in many major projects worldwide. There are over 65 formulations for every refractory application, including;

1. Full thickness relines; 2. original thickness linings; 3. complete refractory veneers; 4. emergency repairs hot or cold.

THERMBOND REFRACTORY STANDARD PACKAGING TYPICAL PRECAST THERMBOND BURNER TILE

IN CONCLUSION :

• Thermbond - reduces down time and Production costs!

• Thermbond refractories are far less sensitive to initial heating. In most applications, this technology allows for heat up rates 2 – 20 times faster than traditional systems. The rapid heat up capability is achieved through the use of the phosphoric acid solution in place of water in mixing the product.

• The Thermbond System

• Using a Liquid Activator results in a complete reaction and no free water. This liquid phosphoric acid is the foundation of the Thermbond binder system and the unique characteristics of its refractories.

• Thermbond - accelerates turnaround and reduces downtime!

• Another result of this combination binder system – Thermbond is that products achieve high green strengths very quickly. Upon mixing an exothermic reaction takes place that hardens the material so that forms, if used, can be removed in one hour. Under most conditions, the exothermic reaction is completed and the aggegate structure is completely cured and ready to heat up in less than four hours after placement. This further accelerates turnaround and reduces down time costs.

• Thermbond – bonds to old fired refractories and never lets go!!

• The chemical reaction that takes place upon mixing of this binder system also creates a chemical bond with very high adhesion characteristics. Because of these characteristics Thermbond refractories can be installed over existing fired refractories as a veneer or repair, with a permanent bond that will not delaminate upon firing. As long as an existing lining is mechanically sound. Thermbond refractories can be cast or gunned over them, enabling a repair instead of forcing an entire replacement. This superior adhesion also makes the installation of Thermbond refractories easier because it eliminates problems associated with cold joints and laminations. They can be poured up against themselves, even if hardened, because of their unique adhesion characteristics.

• Thermbond – resists thermal cycling, cycle after cycle!• Further benefits as a result of eliminating virtually all free water from the mixing process are that Thermbond refractories

exhibit far less cracking, if any, on initial heat-up and in service. Thermbond is much more resistant to thermal cycling when compared to conventional refractories.

• Thermbond – inherently NONWETTING at elevated temperatures for extended periods of time!• Another significant feature of this binder system is that the aggegate matrix, coated evenly with phosphate throughout,

forms a hot face which resists penetration from molten metals particularly molten aluminium, organics, and other materials. Ordinary refractory binder systems are highly susceptible to penetration by molten metals, hydrocarbons and other impurities typically present in refractory environments. Some traditional refractories combat this weakness through the addition of non-wetting additives to the refractory mix. These additives whilst initially very effective, burn out of the refractory system over time or when exposed to temperatures in excess of 1093 deg.C. rendering them even more susceptible than refractories with no such additives since voids are left when they burn out.

• Once penetrated the refractory life is greatly diminished, both as a result of the difference in the coefficient of linear expansion between the refractory product and the penetrating material and also as a result of mechanical abuse due to the attempted removal of the penetrated material.

• Since there are no additives in the Thermbond binder system to burn out or wear out, the lining remains clean for the life of the lining, even after exposure to temperatures of 1600 deg.C. and above. Since the lining stays cleaner, there is far less maintenance and mechanical abuse, resulting in significantly longer refractory life.

•• Finally, despite the phosphate content the Thermbond system is capable of achieving upper temperature limits of more

than 1650 deg.C. This is explained through the combination binder system, which by chemical reaction eliminates the typical limitations of phosphates at higher temperatures and allows ceramic bonding to take place. Therefore, although a phosphate bond is technically incorporated in this system, it is not classified as merely another phosphate bonded refractory.

• The new Thermbond refractory technology offers a number of benefits that are not available in traditional binder systems:

• FAST SET• LITTLE OR NO CURE REQUIRED• OFTEN NO BAKE OUT REQUIRED• BONDS TENACIOUSLY TO ITSELF AND OTHER FIRED

REFRACTORY PRODUCTS• REDUCED CRACKING AND SPALLING• THERMAL SHOCK RESISTANCE• NON WET REFRACTORY SURFACE

Case study POWER PLANT ASH HOPPERThe Thermbond Group recently had an opportunity to supply a large amount of Formula 6-AG gunning material in an ash hopper

in a coal fired power plant in Arizona. The Formula 6AG is a very dense alumina-based mullite gunning material.The ash hopper for the power plant has been problematic over the years resulting in a partial or full lining replacement every 18

to 20 months. One of the biggest problems has been with the use of conventional water based refractories, there is never enough heat reaching these areas to properly dry them out. With out a proper dry out the properties of these conventional materials are very poor resulting in premature failure and constant problems through out the operating cycle.

The turn around was scheduled for 5 weeks with a guaranteed start date. The Thermbond Formula 6-AG material was originally chosen because of its ability to chemically bond to the existing refractory. Initially to save time and money the plant had hoped to over spray several of the worst areas. Upon tear out the plant/contractor discovered the refractory was in far worstshape then anticipated and needed to be completely replaced. In addition to the large increase in the volume of material to be placed the installation had to be pushed back until the very end due to additional mechanical work.

Because of these last minute changes the plant was very pleased to hear that the Thermbond material would air cure in 2 to 3 hours and could be heated up to 260 degrees per hour upon startup. While they had known about these features previously, it now became very clear what a great value Thermbond provided in this new situation and reinforced what a good idea it was to use Thermbond in the first place.

The contractor was familiar with Thermbond having used it in the past. Using two standard Reed guns and working two 12-hour shifts roughly 13 tonne of material was placed in 7 shifts.

Upon startup before any heat could reach the refractory a water feeder head ruptured filling the ash hopper with water up to the man ways. While traditional water based refractory would have been severely damaged or ruined in such a situation the Thermbond due to its chemical bond and exothermic reaction was not in any way adversely affected by the water in its green state. Once the leak was fixed the unit was quickly brought back on line with out any problems with the refractory.

Needless to say the end user was extremely impressed and pleased with the Thermbond Formula 6AG material. They felt that with all the difficulties and problems encountered with the installation that Thermbond was extremely valuable and instrumental in getting them back on line as quickly as possible.

2. Oxistop Ceramic Coatings for Boiler Tubes

Grit blast preparation before ceramic coatingOxistop Procera McG coated on boiler tubes

3. ELKEM CERAFORTE AND CERAMITE WEAR RESISTANT PRECAST BURNER NOZZLES AND SHAPES

CCCC

•Coal classifier with grid fixation and Ceramite® T installation