The invention pertains to a pulverized coal boiler with a bottom burner, comprising: a furnace; at the very least one bottom burner, every burner has a burner nozzle, and the primary air carries pulverized coal upwards into the furnace by way of the burner nozzle; the secondary air The air distribution device is organized at the underside of the furnace across the burner, and is used to inject secondary air upwards, wherein: the secondary air distribution machine contains an inner secondary air distribution device and an outer secondary air distribution system; the interior secondary air distribution gadget The air system includes an interior secondary air header and an internal secondary air pipe, the inner secondary air pipe is linked to the internal secondary air header and is supplied with a plurality of interior secondary air retailers located in the furnace, a minimum of part of the inner secondary air The air outlet is arranged adjacent to the nozzle of the burner; the external secondary air distribution device contains an external secondary air collector and an exterior secondary air pipe, and the external secondary air pipe is related to the external secondary air collector and is supplied with a Multiple outer secondary air shops inside; the internal secondary air header is impartial of the outer secondary air header.
The invention integrates a low NOx burner, a burner hearth 4 nook tangential circle ashes wind nozzle know-how, a flue gas recirculation and a grading know-how, and solves the issues of high boiler denitration price brought on by single utility of the low nitrogen combustion technology and lack of a low nitrogen system within the operation technique of the existing industrial pulverized coal boiler combustion system. Constitution: A swirl-sort revolution-symmetric primary combustion chamber 7 fitted with a burner 2 is related in sequence with a revolution-symmetric secondary combustion chamber eleven through a throat portion 12 fitted with cooling-water nozzles 10. Waste liquid or waste gasoline containing nitrogen compounds, along with an auxiliary gasoline as required, is burnt at a temperature above 1200°C while regulating the total amount of combustion air (from a pipe 4) and air (from a pipe 6) for defending a waste-liquid nozzle eight in such a fashion that the secondary combustion fuel after combustion of the auxiliary gasoline and the whole waste incorporates less than 5% of oxygen.
In one embodiment, the inner secondary air pipe is an annular pipe organized around the nozzle of the burner. Optionally, the inner secondary air pipe and the outer secondary air pipe are arranged parallel to each other. At present, large furnace design, direct current burners, and sq. or octagonal tangential combustion methods are mostly used. When lignite is used as gasoline for power plant boilers, on account of its excessive ash content and low ash melting point, lignite has robust slagging properties. When the sulfur content material in the coal is higher, S within the coal is straightforward to generate extremely corrosive H underneath the motion of reducing atmosphere2S, thereby having adverse results on the left and proper water-cooled wall pipes, forming excessive-temperature reductive sulfur corrosion, and lowering the left and proper water-cooled wall pipesThe problem that the boiler needs to be changed in a large space is solved, and the protected and financial operation of the boiler is severely influenced. The utility mannequin has the advantages that the overfire air is distributed in a shunting and layering approach, so that the mixture is sufficient within the later combustion stage, and the NOx content material at the SCR inlet is decreased. 3) The original emission level of NOx from pulverized coal combustion is high: the unique emission level of NOx is mostly above 200mg/ m3 , the cost of tail denitrification is high, and there is a risk of secondary pollution.
SCR. For the better bituminous coals and with tangential firing, it is generally simpler to realize or meet SCR inlet NOx of lower than 150mg/Nm 3 The necessities of (1); nonetheless, for opposed firing boilers, one of the best level at present can only attain 200-250 mg/Nm three In response to the current opposed-stream combustion expertise, the NOx on the SCR inlet is required to be lower than 150mg/Nm 3 It’s tough or even unattainable. However, the swirl burner used within the widespread counter-combustion method has not been modified much for the traits of lignite. Amongst them: 1 is the central air duct, 2 is the first air powder channel, 3 is the pulverized coal concentrator, 4 is the indented horn-formed flare, 5 is the primary air outlet, 6 is the adjustable internal secondary air swirl blade , 7 is the adjustable external secondary air swirl blade, eight is the inner secondary air channel, 9 is the external secondary air channel, 10 is the secondary air outlet, eleven is the isolated air channel, 12 is the retractable isolated air nozzle, thirteen is an anti-scorch wind channel, 14 is an anti-scorch wind spout, and 15 is an anti-scorch wind cyclone. The interior secondary air channel is provided with adjustable inner secondary air swirl blades, and the outer secondary air channel is provided with adjustable outer secondary air swirl blades. The outlet of the central air duct is provided with a flared flare that step by step increases in measurement along the move course of the central air.