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Show way when risk is well managed and when profits are available to competitively advance the technology. GUARANTEE vs LEVEL OF UNCERTAINTY The technical uncertainty of emissions is inversely proportional to the permissible level of emissions. Negligibly small variances in several operating parameters do cause unacceptable increases in NOx, especially when system complexity is increased substantially to be compliant. One example is the use of large quantities of recirculated flue gas as an inert diluent to hold flame temperatures down and preclude a portion of the N O x formation. The increased flow velocities can exacerbate vibration [14,15], increase the possibility of flashback at the burner [16], and compromise the total particulate matter, PM10, PM2 S , CO, V O C , and N Ox balance. Risk is ameliorated as repeated applications of the same burners and boilers occur and when the overall system is the same and the emissions guarantees are the same. Even then, there are few truly duplicate jobs considering fuel chemistry, air temperatures, site elevation and a whole host of other parameters which have an effect on emissions. Alternatives to solely relying on the burner for the reduction of N O x and other toxic substances are now available. Some of these technologies are; to recirculate greater quantities of flue gas, to rebum additional fuel after the main flame is approximately equilibrated, to install a post treatment catalytic reactor, and to make fundamental process changes. Each of these entail added costs, both capital and operational costs, making them less desirable than relying of the least cost method of achieving the emissions reductions solely with the burner. Precluding the addition of post treatment systems when the burner flame shape and chemistry, in combination with the boiler system, can provide very low emissions will be a more cost effective life-of-the-plant alternative. NOx POLLUTION CREDITS Historically, meeting emissions guarantees has been somewhat of an all or nothing proposition. Either the plant is operated in compliance with the emissions requirements of the environmental permit, or some form of drastic consequence may be imposed, such as paying hefty monthly fines. Recently the sale of N O x credits as a commodity has been discussed along the lines of the proposed carbon dioxide rights with annual market trading worth billions of dollars [17,18]. Burner manufacturers have already been requested to guarantee emissions well below the environmental permit requirement. The benefit is that the plant owner can sell these emissions credits and will therefore purchase the steam generating boiler and burner system, other things being equal, from the manufacturers who are willing to guarantee the lowest emissions. The risks associated with meeting NOx guarantees is substantially different when the guaranteed value makes the difference between operating the plant in compliance with the environmental permit, or earning a incremental income from the sale of N O x pollution rights, or credits. The burner manufacturer currently shares most, if not all of the permit required guarantee risk. The reward from the use of or sale of credits will likely be an inducement to achieve the lowest possible emissions for every site. CONCLUSIONS The means to control emissions from flames by exploiting the temperature sensitivity of the chemical reactions and by carefully fitting the flame to the boiler furnace shape, have been discussed above. When these are implemented, the least cost of ownership for the life of the plant and the least cost per unit of toxic substance precluded from entering the atmosphere will be realized. For example, in lieu of approximately $300.00 to $600.00, or more, per ton of N O x precluded via downstream systems such as SCR, S N C R or rebum, the precision shaped flame, low emissions, low excess air, high efficiency boiler burner flame will enable many plants to realize the desired cost effective, ultra-low emissions intended by M A C T and other future regulations for considerably less. The added flame improvements will cost less than $100.00 per ton of NOx. Chemical equilibrium shifts and intermediate reaction mechanisms which predominate in highly non-adiabatic boiler burner flames, but not in nearly adiabatic flames (e.g. aircraft engine combustors) are more readily quantifiable than ever before. The use of frequency modulated laser spectroscopy, among other techniques, have enabled measurement of extremely short lived radicals which influence reactions yielding N , N O , N 2 0 , N 0 2 , and N2. This improved understanding of flame chemistry, including the time dependency of prompt N O , is being beneficially exploited in the advancement of the applied sciences of combustion, emissions and flames. Advanced technology dual fuel burners will be evolved by industry leaders who perceive the market advantage they gain, provided the low emissions risk is reasonably managed and their business remains sufficiently profitable to fund the development efforts. It may not be in the best interests of any business to guarantee highly difficult to achieve emissions, especially a minor financial player like a |