Fire wall

NOj Control. NO control limitations are described in both Tide 1 and Tide 4 of the CAAA of 1990. Tide 4 requirements affect only coal-fired boilers and take effect at the same time that the boilers are impacted by CAAA SO2 requirements. As of 1996, EPA had estabHshed Tide 4 NO limits only for tangentially fired and waH-fired, dry-bottom boilers that would be impacted by Phase I of the CAAA SO2 regulations (Tide 4). Limits of 0.22 kg/10 kJ (0.5 lb/10 Btu) and 0.19 kg/10 kJ (0.45 lb/10 Btu) have been set for wall-fired and tangentially fired units, respectively. The EPA based these levels on what was achievable using low NO burners. However, plants can employ a number of different front- or back-end emissions controls, including a combination of options, to achieve these levels. EPA plans to announce Tide 4 NO requirements for 300 additional boilers by late 1996 or eady 1997. 

Probability of fire spread, with a need for, e.g., fire walls, fire doors, fire stops. 

Define location of fire walls, fire hydrants. 

Delichatsios, M. A., "Flame Heights in Turbulent Wall Fires with Significant Flame Radiation", Comb. Sci. Tech., 39, p. 195, 1984. 

Ahmad, T. and Faeth, G.M., Turbulent wall fires, in 17th Symposium. (International) on Combustion, The Combustion Institute, Pittsburg, Pennsylvania, 1978, p. 1149. 

For turbulent wall fires, from the work of Ahmad and Faeth [18], it can be shown that... 

The next experiments are conducted on a 500-pound-per-hour combustor. This combustor, which simulates commercial practice, is shown in Figure 2. It is a wall-fired, dry-bottom unit which uses cyclone ash collection. Where possible both coal and ash samples are obtained from commercial power plants to verify the results from the experimental combustors. The combination of the two programs will hopefully give... 

Instead of gas turbine exhaust, air preheat has been used in some plants to reduce fuel consumption. Flue gas leaving the furnace stack passes through an air preheater, and the preheated air is supplied to the burners. By using mostly hearth burners, the duct work and the investment cost can be minimized with air preheat and gas turbine exhaust. It is also possible with 100% wall-fired furnaces, and has been proven in commercial operation (34). 

There is no net radiative exchange between the enclosing walls (fire-box), and the radiating gas and tubes. Heat is lost from the enclosing wall to the surroundings only. 

Specifically, the work done at Plant Sweatt examined the applicability of 1x liquid synthetic fuels to a full scale, wall fired utility boiler 1n terms of boiler efficiency and emission characteristics. EPRI sponsored testing with synthetic fuels at other sites Included small scale combustors, a Combustion Engineering wall-fired utility boiler, a Combustion Engineering tangentially-f1red utility boiler, a combustion turbine and diesel piston engines with generally favorable results. 

Demonstrate the use of coal derived liquids as potential substitutes for petroleum fuel oil in a full scale, wall fired utility boiler. 

NFPA 221 Standard for High Challenge Fire Walls, Fire Walls, and Fire Barrier Walls... 

The other major type of pulverized-coal-fired boiler is the wall-fired boiler. In wall-fired units, instead of being mounted in the comers, the burners are mounted on the walls of the furnace. They may be mounted on only one wall, or they may be mounted on opposing walls. The burners typically are mounted in a grid pattern. 

Description Natural gas or another hydrocarbon feedstock is compressed (if required), desulfurized, mixed with steam and then converted into synthesis gas. The reforming section comprises a prereformer (optional, but gives particular benefits when the feedstock is higher hydrocarbons or naphtha), a fired tubular reformer and a secondary reformer, where process air is added. The amount of air is adjusted to obtain an H2/N2 ratio of 3.0 as required by the ammonia synthesis reaction. The tubular steam reformer is Topsoe s proprietary side-wall-fired design. After the reforming section, the synthesis gas undergoes high- and low-temperature shift conversion, carbon dioxide removal and methanation. 

Haldor Topsoe Side-wall fired Radiant 2.11... 

Hour Two 3-hour doors for MFL walls, fire walls and where specifically required by code, or one 3-hour door for other walls. 

Industrial Risk Insurers, Fire Walls, Fire Barriers and Fire Partitions. IRInformation IM.2.2.1, June 1, 1992. 

New tube materials allow the design for much higher exit temperatures and heat fluxes, in particular when applying a side wall fired reformer furnace to ensure better control of the maximum tube wall temperature and optimum use of the high alloy material. Thinner tube walls made possible by the use of the new materials reduce the risk for creep due to faster relaxation of stresses at start and stop of the reformer (14). 

The burner orientation with respect to the combustor is also sometimes used to classify the combustor. For example, a wall-fired furnace has burners located in and firing along the wall. 

Typical muffler for a radiant wall-fired natural draft burner. (From Baukal, C.E., Industrial Combustion Pollution and Control, New York Marcel Dekker, 2004.)... 

Field data - Low NO., premix, radiant wall burners Field data - High NOj., premix, radiant wall burners A Test data - Wall-fired, diffusion burner - - Exponential fit of Low NO., premix data — — Exponential fit of High NO., premix data Exponential fit of Wall-fired, diffusion data ... 

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