many real time processes have complex, uncertain and nonlinear dynamics. boilers are nonlinear, time varying, multi-input multi-output (mimo) systems, whose states generally vary with operating conditions. the major problem in controlling that system is that its drum water pressure and steam flow dynamics include an integrator that results a critically stable behavior. conventional controller p...

The management of coal ash in utility boilers continues to be one of the most important fuel property considerations in the design and operation of commercial boilers. The behavior of mineral matter in coal can significantly influence furnace sizing, heat transfer surface placement, and convection pass tube spacing. Ironically, many of the more reactive, low rank U. S. coals must have larger fu...

To assist the federal government in meeting its energy reduction goals, President Clinton’s Executive Order 12902 established the Procurement Challenge, which directed all federal agencies to purchase equipment within the top 25~ percentile of efficiency. Under the direction of DOE’s Federal Energy Management Program (FEMP), the Procurement Challenge’s goal is to create efficiency recommendatio...

In industrial applications, 90-150°C hot water needed during production processes is traditionally provided by fuelfired boilers. The use of fuel-fired boiler has a low efficiency of energy usage and potential danger of explosion. Byproduced 30-60°Cwaste water with large amount of energy is rejected to environment directly, which causes a great energy loss and thermal pollution. Seeking for a h...

Sugar contamination of boiler feedwater by smallcontinuous traces is not as serious as that from large 'slugs' which frequently find their way into the boilers. Reference is made to several incidents of sugar contamination in boilers to showthat the most commoncauses are a malfunction of the feedwater system or its mismanagement, and to show that the method of sugar detection is seldom at fault...

Currently, the use of emission controls on wood boilers is limited and has seen incremental forward movement, as compared with the advances used in Europe. The use of advanced boiler designs, as well as, the use of emission control devices such as ESPs and baghouses are commonly deployed in Europe on small wood boilers (units 1 million Btus and larger). However, in the United States the use of ...

Renewable energy sources are essential paths towards sustainable development and CO2 emission reduction. For example, the European Union has set the target of achieving 22% of electricity generation from renewable sources by 2010. However, the extensive use of this energy source is being avoided by some technical problems as fouling and slagging in the surfaces of boiler heat exchangers. Althou...

As part of climate change commitments, the United Kingdom is considering an incremental transition from natural gas to hydrogen for domestic heating, blending up 20% (by volume) into national network. We consider possible impacts this policy on nitrogen oxides (NOx) emissions, a minor waste by-product combustion. A meta-analysis changes in NOx emissions hydrogen/natural blends used burners unde...