Abstract:
Provided is a vertical pulverizing apparatus capable of suppressing abrasion of throat vanes (40) and elongating their abrasion resistant lives to thereby increase working efficiency. The vertical pulverizing apparatus is characterized in that: a throat (4) is provided between a housing (32) and a pulverizing table (2) and has an annular flow channel which is surrounded by a throat inner peripheral wall (41) and a throat outer peripheral wall (42) and which is partitioned by a large number of throat vanes (40); and a slope part (43a, 43b) extending diagonally downward from an inner peripheral wall surface of the housing (32) toward a top end of the throat outer peripheral wall (42) and a horizontal part (44) extending from a bottom end of the slope part (43b) continuously to the top end of the throat outer peripheral wall (42) are provided so that top end surfaces (40a) of the throat vanes (40) and a top surface of the horizontal part (44) can be set at the same height.
Abstract:
A system for drying pulverized high moisture fuel for use in a selective catalytic reduction system equipped combustion system is provided. The combustion system includes a mill for pulverizing fuel, an air heater, two fuel gas streams at different temperatures, a booster air heater and a fuel duct for feeding dried pulverized fuel to a combustion furnace.
Abstract:
A biomass pulverizing apparatus includes a pulverizing apparatus body including a feedstock supply pipe, the pulverizing apparatus body for supplying biomass feedstock from above in a vertical axial direction, a pulverizing table for placing the biomass feedstock, a drive section for rotationally driving the pulverizing table, a pulverizing roller for pulverizing the biomass feedstock by a pressing force, the pulverizing roller being operated in conjunction with the rotation of the pulverizing table, a blower unit for forming an upward flow upward from below on the outer peripheral side of the pulverizing table so as to jet conveying gas for conveying the pulverized biomass powder in an air stream, a classifier, the classifier for classifying the biomass powder accompanied with the conveying gas, and a blowing gas introduction section.
Abstract:
A system and method for drying pulverized high moisture fuel for use in a selective catalytic reduction system equipped combustion system is provided. The combustion system includes a mill for pulverizing fuel, an air heater, a booster air heater and a fuel duct for feeding dried pulverized fuel to a combustion furnace.
Abstract:
A method for producing pulverized coal including the steps of providing a drying gas heated to a predefined temperature in a hot gas generator; feeding the heated drying gas into a pulverizer; introducing raw coal into the pulverizer, the pulverizer grinding the raw coal into pulverized coal; collecting a mixture of drying gas and pulverized coal from the pulverizer and feeding the mixture to a filter, the filter separating the dried pulverized coal from the drying gas; collecting the dried pulverized coal for further use and feeding the drying gas from the filter to an exhaust line; and collecting the drying gas exiting the filter and feeding part of the collected drying gas to a recirculation line for feeding recirculation drying gas to the hot gas generator. According to an important aspect of the present invention, the step of providing the drying gas includes feeding a variable flow rate of hot stove waste gas to the hot gas generator through a hot stove waste gas line so as to maximize the amount of hot stove waste gas used as drying gas. A pressure of the drying gas at a pulverizer gas inlet is controlled by regulating a flow rate of the hot stove waste gas through the hot stove waste gas line.
Abstract:
The subject mater herein relates to coal mills and, more particularly, inferential pulverized fuel flow sensing and manipulation within a coal mill. Various embodiments provide systems, methods, and software to manipulate a primary air flow rate and a coal feed rate into a coal mill to produce a target pulverized fuel flow. Some embodiments include sensing a differential pressure between two or more locations within a coal mill to estimate a recirculated load of coal at one or more stages within the coal mill.
Abstract:
A process for energy recovery and transfer including: warming fresh air in a heat recovery and pressure control unit; feeding waste feed and the warm fresh air into a processor; reducing a moisture content of the waste feed by breaking the waste feed into a fuel powder in the warm fresh air in the processor; filtering contaminated air through an initial filter to remove the fuel powder from the contaminated air; pre-heating the contaminated air in the heat recovery and pressure control unit; raising the temperature of the pre-heated contaminated air in a chamber; passing the chamber discharge air through the heat recovery and pressure control unit to pre-heat contaminated air passing on to the chamber and to warm fresh air passing on to the processor; and filtering terminal air through a terminal filter to remove particles from the terminal air.
Abstract:
The present invention is a system and method of reducing nitrogen oxides in coal combustion exhaust gases and preventing fire and explosion in pulverized coal systems. The present invention first cools the flue gas exiting a boiler of the pulverized coal system with an air preheater. The present invention removes any particles such as fly ash from the cooled flue gas with an electro-static precipitor or a bag house and recirculates the flue gas. The temperature of the recirculated flue gas is adjusted to a desired temperature and is injected into the pulverizer with combustion air from the air preheater, creating a safer environment for pulverizing the fuel. This mixture of pulverized fuel, air and flue gas is then burned in the boiler, resulting in a cleaner output containing significantly less nitrous oxide.
Abstract:
A combustion burner includes a mixture nozzle (2) defining a mixture fluid passage through which a mixture fluid (1) containing pulverized coal and conveyor gas flows toward a furnace, secondary and tertiary air passages surrounding the mixture nozzle (2), through which secondary air (6) and tertiary air (9) for combustion purposes flow, respectively; and air injection nozzles (24) provided in the vicinity of an outer periphery of a distal end of the mixture nozzle (2). The air (21) is injected from the air injection nozzles (24) toward the axis of the mixture nozzle, so that the high-temperature gas in the vicinity of the outer periphery of the distal end of the mixture nozzle (2) is drawn into the mixture fluid (1) in the vicinity of the outer periphery of this distal end.
Abstract:
A method and apparatus retrofitted to a multiple-intertube pulverized-coal burner to reduce NO.sub.x emissions of roof fired boilers. An internal two stage process controls the amount of secondary air which flows to the burner. The first stage includes a secondary air damper and air flow station to regulate the amount of air which flows into a windbox of the burner. A baffle plate assembly which includes a plurality of baffle plates further limits the amount of air which flows to the core of the burner for combustion of the fuel. The baffle plates create a pressure drop within the windbox which forces or diverts a quantity of air to the periphery of the burner. The second stage includes an outlet formed in the hot primary air duct, an air plenum which communicates therewith, and a plurality of interjectory air ports which correspond with the burners in number and position along a front wall of the boiler and which communicate with the air plenum. The interjectory air ports inject interjectory air into a combustion chamber of the boiler at a substantially 90 degree angle to the direction of a plurality of burner tips of each burner and supplies the balance of the required theoretical combustion air needed to complete combustion of the fuel. A plurality of probes measure the amount of primary air, secondary air and interjectory air and signal a command loop circuit to adjust the secondary air dampers and interjectory air ports accordingly.