Wood fired power plant

Also, wood fuel is low in sulfur, ash, and trace toxic metals. Wood-fired power plants emit about 45% less nitrogen oxides, NO, than coal-fired units. Legislation intended to reduce sulfur oxides, SO, and NO emissions may therefore result in the encouragement of wood-burning or cofiring wood with coal. 

Particulate control is by means of either a wet scrubber or a wet electrostatic precipitator located after the condensing heat exchanger. The choice of particulate control equipment depends on the degree of control required. The particulate slurry collected by the scrubber or precipitator is circulated through a pug mill that de-waters and pelletizes the ash. The ash pellets are spread on the tree fields as a fertilizer. The ash content of the wood is less than 1% so that a maximum of 5 t/day are collected and pelletized. The particulate emission standard to be met for new wood fired power plants in the State of Wisconsin, for exan le, is based on best available control technology (BACT) and can be expected to be about 21 g/ 10 kj. 

Mcllveen-Wright D. R, Williams B. C., and McMuIIan J. T. (1997) Electricity generation from wood-fired power plants the principal technologies reviewed. In Developments in thermochemical biomass conversion (Ed. by A. V. Bridgwater and D.G.B.Boocock). pp 1525-1538, BLACKIE ACADEMIC PROFESSIONAL. 

Based on a reasonable energy balance and load factor for a 50 MW wood-fired power plant, it was estimated that the City of Burlington requires approximately 470,000 green tons of wood residue/year to operate their power plant. Several assumptions were made to determine if that quantity of material is available to the City. 

Estimates of the capital, operating, and maintenance costs of the proposed 50 MW wood-fired power plant are presented in Table III and are based on conceptual design concepts. All costs are expressed in 1977 dollars. The total construction cost estimate was 46,227,000. 

TABLE III. CAPITAL COST ESTIMATE FOR 50 MW WOOD-FIRED POWER PLANT AT BURLINGTON, VERMONT (All costs exprassed as 1,000 In 1977)... 

According to our analysis, the generation of electricity from wood waste is technically feasible and economically attractive. The most difficult problem in implementing a wood-fired power plant is perceived as being of institutional nature. These concerns are primarily associated with forest management, the economy, and environmental considerations. 

The operation of a 50 MW wood-fired power plant could have significant and positive impacts on Vermont and the City of Burlington. The following are a few of the potential impacts ... 

Wood-fired power plant and algae pond for wastewater treatment ... 

A wood-fired power plant is included in the PEF system to produce electricity from the solid fuel produced on the dry-land Energy Plantation. Some of the various elements included in the power plant subsystem and the model are shown in Figure I. The power cycle modeled is a conventional steam Rankine cycle as is used in coal-fired and nuclear power plants, in keeping with the decision that the model should represent "state-of-the-art" equipment which would be readily available for a demonstration system. The system components are similar to those that would appear in a simple coal-fired power plant with the additional equipment to dry and screen the fuel before it enters the boiler. 

A correlation for parasitic power for a wood-fired power plant was developed from a correlation for coal-fired plants given in the literature (88) and an analysis of the relative amounts of power used in the fuel-handling system... 

In a similar fashion, cost correlations for large wood-fired plants were developed from correlations available in the literature ( ) for installation cost, and operation and maintenance cost for coal plants. The costs for a wood-fired power plant were found to be 20 percent higher than those for a coal-fired plant of the same size. On this basis, cost equations for large wood-fired power plants are as follows (in 1976 dollars) ... 

Analysis of cost data for installation costs for smaller wood-fired power plants yielded the following correlation ... 

Figure 2, Fuel and electricity costs for wood-fired power plant at Natchitoches, LA, and average electricity costs for coal-fired power plants vs. generator capacity...

Figures 31.6 and 31.7 show a schematic and general view of the bedmixing dryer, respectively, while Figure 31.8 presents a flow diagram of a peat- and wood-fired power plant utilizing this novel drying concept. The dryer can be any type, but the simple flash dryer was used in the trials reported since only a few seconds are needed for drying the fuel due to...

Figure 31.8 Flow diagram of the bed-mixing dryer in the peat- and wood-fired power plant. (Courtesy of IVO Technology Centre, Vantaa, Finland.)...

Irving, J. 1993. Wood Fired Power Plant Experience at the 50 MW McNeil Station. Proc. Strategic Benefits of Biomass and Waste Fuels. Washington, DC. March 30-April 1. EPRI, Palo Alto, CA. 

A h) othetical 50 megawatt wood-fired power plant (similar to one already in service in Vermont) is proposed for construction in central Maine. It would burn wood waste produced by the logging industry. Assume the plant would consume 0.6 kg of dry wood (CH2O) per hour per kilowatt, thus consuming 30,000 kg of wood per hour. Assume that 0.1% of the wood s mass is released as fly ash at the 30 m effective stack height. 

Ash from a wood-fired power plant (as in Exercise 44) comprises mainly oxides of alkali (Na, K) and alkaline earth (Mg, Ca) metals and creates an average particle concentration of 27 pg/m in the air over a small watershed covered by a fir forest. To determine whether ash deposition could offset to some degree the effects of acid... 

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