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US 4,057,021 AGranted
Combustion of pulverized coal
OwnerFritz Schoppeinventor
Life of this patent
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Abstract
This invention relates to a process and apparatus for the combustion of pulverized coal, wherein the pulverized coal is introduced into a conditioned atmosphere having an overpressure, the overpressure being used to accelerate a flame jet, and wherein the flame jet is injected into an atmosphere having a temperature below the ash melting temperature of the fired coal.
Claims36
Method for the combustion of pulverized coal, which comprises the steps of:
- a. injecting a pulverized coal into a chamber containing atmosphere having the following characteristics:
- i. a static pressure of at least 20 mm WG above the static pressure in the fire tube of a boiler, based on a boiler capacity of 250,000 Kcal/h;
- ii. an O.sub.2 content of less than 10% by volume;
- and
- iii. a temperature sufficient to heat said pulverized coal at a rate of at least 1000.degree. C/sec;
- b. heating the thus injected coal in said chamber at said heating rate to a temperature at least 100.degree. C above the ignition temperature of said coal;
- c. mixing the thus heated pulverized coal with a gaseous mixture consisting essentially of combustion air to cause combustion of said coal;
- d. accelerating a burning flame jet by means of said excess pressure after combustion of at least 30% of the calorific value of said pulverized coal;
- and
- e. injecting the thus accelerated, still burning flame jet into a gas having a temperature below the ash melting temperature of said pulverized coal.
7 more elements
A device for combusting pulverized coal which comprises a combustor having a combustion chamber therein;
- tangential feeding means having a combustion air flow angle .alpha.;
- a feeding tube for said combustion air connected to said feeding means, said combustor widening conically toward the said combustion chamber, said feeding means being positioned at the narrowest cross-section of said combustor an acceleration nozzle opening into said combustion chamber;
- said device having the following dimensions for a boiler capacity of 200,000 to 250,000 Kcal/h and a pressure drop of combustion air when flowing through the said combustor of 100 mm WG:
- a combustion air flow angle .alpha. of the tangential feeding means of approximately 7.degree.-11.degree., an axial length of the tangential feeding means of approximately 85 mm, a combustor intake diameter of approximately 145 mm, a combustor outlet diameter of approximately 290 mm a combustor length of approximately 560 mm, a feeding tube for the combustion air with a diameter of approximately 300 mm;
- said dimensions, with the exception of the combustion air flow angle .alpha. varying with the boiler capacity proportionally with the square root of the capacity ratio.
2 more elements
A device for combusting pulverized coal which comprises:
- a combustor;
- tangential feeding means having a combustion air flow angle .alpha.;
- a feeding tube for said combustion air connected to said feeding means, said combustor widening conically away from said feeding means, said feeding means being positioned at the narrowest cross-section of said combustor;
- an acceleration nozzle connected to the largest cross-section of the said combustor;
- said device having the following dimensions for a boiler capacity of 200,000 to 250,000 Kcal/h and a pressure drop of combustion air when flowing through the combustor of 100 mm of water;
- a combustion air flow angle of the tangential feeding means of approximately 7.degree.-11.degree., an axial length of the tangential feeding means of approximately 85 mm, a combustor outlet diameter of approximately 145 mm, a combustor intake diameter of approximately 290 mm, a combustor length of approximately 560 mm, and a diameter of said feeding tube for the combustion air of approximately 300 mm.
3 more elements
Dependencies are inferred from the claim text.