Combustion equipment, system

A safety shutdown of the oxy/fuel combustion equipment system by any of the prescribed safety features or devices shall require manual intervention of an operator for reestablishment of normal operation of the system, per NFPA 86 (sect. 5-2.3). 

Typically, an oxy/fuel combustion equipment system is considered to be a Class 1, Division 2, Group D electrical installation per NFPA 70 (articles 500, 501, and 502). Note that the Group is defined as a function of the flammable fuel being handled. See NFPA 497A for help in determining the classification of a particular oxy/fuel combustion application. All components, enclosures, conduits, and wires must be suited for the particular classification of the oxy/fuel equipment system electrical installation. 

An Operating and Maintenance Manual is required for every oxy/fuel combustion equipment system per NFPA 86 (sect. 1-5.6). As a minimum, the manual must include oxygen and fuel safety literature appropriate approved drawings of the... 

Fluiaized-Bea Boilers As explained in the earlier discussion of coal combustion equipment, the furnace of a fluid-bed boiler has a unique design. The system as a whole, however, consists mainly of standard equipment items, adapted to suit process requirements. The... 

A flame trap is employed where premixed air and gas is used in combustion equipment and prevents the flame passing upstream into the pipe system. Flame traps should be situated as near as possible to the gas burner. This is so that the flame does not have a long pipe mn in which it might accelerate to such a speed as to form a detonation wave and make the trap useless. 

Although some integration has taken place where the appliance or boilermaker has assumed responsibility for the combustion system, overall, specialist manufacturers of combustion equipment who have developed products for each application such as boilers, furnaces, kilns and dryers, etc. serve the market. The burner makers have manufactured products which provide a packaged solution to the combustion requirement, looking after not just the burners and controls but also the fuel supply system, which may involve pumping, heating of the fuel, filtration and other peripheral equipment and functions. 

Overall, EGR and combustion/injection systems constitute the key factors to comply with the EuroIV standards (applied in January, 2005). The EuroIV step exhibits EuroIII NO and soot particles limits divided by 2. Besides, vehicle s weight is always increasing due to the introduction of new safety systems and equipment. Therefore, pollutants emissions increase and a supplementary effort to reach the normative threshold is to be made. To comply with this target, some evolutions have been introduced, as for example multi-injection or water-cooling of the EGR system. The NO,/particle compromise adjustment remains possible for most of the applications without any after-treatment system like the Diesel particle filter (DPF). 

To assist in the location of air inlets for ventilation systems and combustion equipment... 

Specific Heat Release Rate. To utilize many combustion systems most effectively, the maximum power output is to be obtained for the smallest possible size and weight. As a result, the physical size of the combustion chamber as well as all other components should be held to a minimum. This requirement specifies that the specific heat release should be as high as possible. This quantity, usually expressed in energy units per unit volume, unit time, and unit pressure squared, is a measure of the ability to heat the gases used in the thermodynamic cycle. Some idea of the orders of magnitude of prevailing heat releases in combustion equipment can be obtained from the values in Table II. 

During the industrial age, COz concentration in the ambient air increased from 280 to 360 ppm, and some predict that it could rise to 550 ppm if the use of fossil fuels continues. In addition to monitoring the atmosphere, air-quality-related measurements can also be used in heating, ventilation, and air conditioning (HVAC) systems to monitor the return air quality from occupied spaces. COz is also measured at emission points because some combustion equipment regulations limit, or probably will limit, allowable discharges. 

Laminar flowmeters are used in the testing of internal combustion equipment, in semiconductor manufacturing, leak testing, fan or blower calibration, and lately in alternative energy processes. The recommended installation practice is to provide 10 to 15 diameters of straight pipe upstream of the flow element. It is also highly recommended that the system be calibrated using the same gas as the process gas to be measured. 

CEM systems have been developed to monitor pollutant gases, such as SO2 and NO, and the so-called diluent gases, CO2 and O2, present in the exhaust gas streams of combustion sources. Systems have also been developed to monitor flue-gas opacity. A system is defined as the total equipment required for the determination of flue gas opacity, a gas concentration, or the emission rate. A CEM system is normally composed of a sample interface, the pollutant and diluent analyzers, and a data recording subsystem. The system is used to generate emission data that are representative of the total emissions from the facility. 

Direct Combustion Systems. The direct combustion of biomass feedstocks is already widely practiced by several industries, especially the forest products industry. Many types of direct combustion equipment are commercially available for this purpose. New developments in direct combustion technology are expected to have a near term impact on energy supplies through the utilization... 

This book is targeted primarily toward that end user, the one who is responsible for implementing the use of oxygen in a combustion system. However, others should find the book of interest as well, including combustion equipment and industrial gas... 

In most practical combustion installations there are two separate parts of the equipment system (1) the burner itself and (2) all of the peripheral equipment necessary to control the burner operation efficiently and safely. The control equipment includes fuel and oxidant pressure and flow controls automatic shutoff controls flame supervision equipment furnace purge equipment and other related devices. The safety issues of the burner are significantly different in character as compared with the safety issues of the control equipment. In many ways, these two safety issues are diametrically opposed. Within the burner, fire is a desired condition, whereas within the control system and surrounding environment, fire is to be avoided entirely. 

Thyssen-CEA Environmental Systems, Inc. (initially Combustion Equipment Associates, Inc.) and Arthur D. Little, Inc., have developed, over the past few years, a dual alkali process for removing SO2 from flue gas generated in coal-fired utility boilers This process is based on the absorption of SO2 in an alkaline sodium solution, followed by regeneration of the absorbing solution by reaction with a second alkali, calcium. These reactions generate insoluble calcium-sulfur salts which are discharged from the system as a moist cake. 

The successful performance in the pilot plant tests prompted the testing of the technology at a prototype scale (20 MW). The project was sponsored by EPA, who provided most of the funds by Thyssen-CEA Environmental Systems, Inc. (initially Combustion Equipment Associates, Inc.) who also contributed to the funding of the project by Gulf Power Company and by Southern Company Services, Inc. 

Relative to other advanced combustion conversion systems, such as magnetohydrodynamics (MHD), ceramic blade turbine gas turbine, and potassium Rankine cycle, thermionic development costs should be substantially lower. The cost effectiveness is a result of the modularity of thermionics, which makes it possible to perform mean-ingftil ejqreiiments with small equipment. Thus, large investments should not be required until there is a high prob-abihty of success. 

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