CN102639681A

CN102639681A - A method for improving the efficiency of heat transfer in a coal fired furnace

Info

Publication number: CN102639681A
Application number: CN2010800547795A
Authority: CN
Inventors: V·T·韦尔德伊; L·E·沃尔瑟
Original assignee: Baker Hughes Inc
Current assignee: Baker Hughes Holdings LLC
Priority date: 2009-12-08
Filing date: 2010-12-02
Publication date: 2012-08-15
Also published as: RU2012128356A; WO2011071741A2; AU2010328491A1; WO2011071741A3; EP2510077A2; EP2510077A4; US20110131874A1

Abstract

An additive having as components, at least three metal oxides selected from iron, manganese, cobalt, and copper oxide, may be added to coal to reduce the brightness of ash produced therewith. Further, the additive serves to increase the heat transfer efficiency of furnaces.

Description

Improve the method for heat transfer efficiency in the coal-fired stove

Background technology of the present invention

Technical field of the present invention

The present invention relates to the coal-fired stove system.The present invention is particularly including the coal-fired stove that is used for additive is added the system of coal.

Background technology

The stove that is used for giving birth to heat is all used in petrochemical equipment, refinery, power house etc.Since the several centuries, people rely on combustible material for example the burning of coal and timber heat energy is provided.A kind of usual method of managing this heat energy is the fluid that utilizes heat energy to produce steam or heat other type.

Since over the years, different types of stove or boiler have been developed with coal combustion, timber and other combustible material.Early stage the fifties in the twentieth century later stage forties and twentieth century, because the extensive availability in relatively cheap oil and gas source, reduce in a large number for the demand of the system of commercial and industrial buring solid fuel.Therefore, oil firing gentle system has replaced the system of burning coal basically, and the petroleum based fuels of G&O becomes not too abundant during twentieth century seventies.The very high price in the oil shortage that twentieth century experienced during the seventies and the end of the year in 2000 makes that burning coal has very large magnetism once more with other solid-fuelled system of burning.

In recent years, pay much attention to solid-fuelled research,, do not have excessive pollutant emission simultaneously and have the heat transfer efficiency of increase particularly in buring solid fuel for example coal and timber field.Along with the gentle cost of oil continues progressively to raise, the utilization of solid fuel system (for example burning the coal measures system) increases continuing.

Summary of the invention

In one aspect, thereby the present invention is used for handling the method that coal improves the coal-fired stove heat transfer efficiency, comprising: before coal combustion or simultaneously, coal contact with additive, wherein: the function of additive is that the radiogenic heat of enhancing coal ash adsorbs; Do not comprise fusing assistant with additive.

On the other hand, thereby the present invention is used for handling the method that coal improves the coal-fired stove heat transfer efficiency, and comprising: coal is contacted with additive, and wherein additive is the pigment that comprises at least 3 kinds of oxide compounds that are selected from Fe, Cu, Co and Mn oxide compound.

Description of drawings

Those skilled in the art are with the advantage and other method of comprehensible present disclosure, because with reference to following detailed description, when considering with accompanying drawing, these advantages of present disclosure will be better understood with other method:

Fig. 1 is the figure with the ash content of 0.01% additive treating;

Fig. 2 is the figure with the ash content of 0.02% additive treating;

Fig. 3 is the figure with the ash content of 0.05% additive treating; With

Fig. 4 is the figure of untreated ash content sample.

Embodiment

In one embodiment, thus the present invention is used for handling the method that coal improves the coal-fired stove heat transfer efficiency.Developed a kind of such stove, mechanize adds coal stove (stoker-fired furnace), with the big relatively coal particle of burning, about at the most 1.5 inches of diameter.Afterwards, developed another kind of stove, pulverized coal firing boiler (pulverized coal-fired furnace), with the much little coal particle that burns, for example wherein about 70% coal particle is through 200 purpose screen clothes.Pulverized coal firing boiler has big steam and produces ability, wherein needing therefore to be generally used at least 500,000 pound of steam/hour steam generation device in.For example, power generation industry has been one of largest user of pulverized coal firing boiler, because need a large amount of steam to be used to produce electric energy.

Use any stove, coal is added the stove burning to produce heat.In some stoves, not burning at once when coal drops on the fire grate, the combustion fuel berth is on fire grate.In some embodiments, fire grate is with the for example about 5-40 foot of low-down speed/hour move, and combustion by-products (being residual ash content) pours in ashcan or some other containers the most at last.Perhaps, fire grate can be an immobilized, but can regularly topple over the ash content bed that adds up to go out.In some stoves, flushing combustion fuel bed.

A universal reason of travelling grate spreader stoker boiler (spreader-stoker-fired furnace) is that it has at the most 750,000BTU/hr-ft ²High surperficial fire grate HRR with it through increase rate of combustion almost moment the low inertia (inertia) that has of fuel ignition.Because the violent burning on the degree of depth that the coal particle layer is relatively little on distribution, the fire grate relatively uniformly in the combustion fuel bed of coal particle on fire grate and the combustion fuel bed during the suspension stages has obtained and should height surface fire grate heat discharge.Low inertia allows the fluctuation of load in the quick corresponding steam demand of travelling grate spreader stoker boiler, and the therefore fluctuation of boiler load, and this is a phenomenon common in the industrial application.

In the practice of the application's method, can treat the incendiary coal with additive treating.In one embodiment, additive is the pigment that comprises the oxide compound of iron, copper, cobalt and manganese.This pigment and coal ash interact, and make the ash content deepening.

Through making the coal ash deepening, strengthened the heat transfer in the stove.Though do not hope, it is believed that when ash content when being dark, attached to the absorbing radiation heat more fully of the ash content on the furnace wall by any theory.Particularly when the surface is Tube Sheet of Heat Exchanger, quantity of radiant energy can along with common convective heat transfer to heat-transfer medium, cause more heat to arrive heat-transfer medium, therefore strengthen the efficient of stove.

The additive of present disclosure does not comprise fusing assistant.For example, need not to add for example borate of fusing assistant.Common fusing assistant and concrete borate fusing assistant are that those skilled in the art are known.An advantage of the additive of present disclosure is that it and ash content need not fusing assistant together.Other pigment if do not adhere to coal ash, possibly be problematic.For example, some pigment possibly cause the problem of opacity upwards through the flue of coal stove.Possibly there is disposal concerns in other pigment.

Though the additive of present disclosure can use with the coal of any kind of, expectation is used with the coal with high calcium contents.This coal produces the ash content of relative light colour, even for the remarkable lifting of heat transfer efficiency very small amount of additive can be provided.

Additive of the present invention is the mineral dye that comprises at least 3 kinds of oxide compounds of copper, iron, cobalt and manganese.In some embodiments, can there be all 4 kinds of metals.In some embodiments, additive can contain: the copper oxide of the about 60 weight % (in metal) of about 15-; The Mn oxide of the about 70 weight % (in metal) of about 20-; The cobalt of the about 70 weight % of about 20-; Ferriferous oxide with the about 30 weight % (in metal) of about 5-.In other embodiments, additive can contain the copper oxide of the about 45 weight % (in metal) of the 25-that has an appointment; The Mn oxide of the about 60 weight % (in metal) of about 35-; The cobalt of the about 60 weight % (in metal) of about 35-; Ferriferous oxide with the about 25 weight % (in metal) of about 10-.

Can additive be added coal, or can fashionable it directly be added stove coal being acted as a fuel add.In one embodiment, before with coal dustization, with additive as liquid spraying to coal.In a kind of such embodiment, use nozzle to spray.In another embodiment, after coal efflorescence, with additive as liquid spraying to coal.In another embodiment, additive is introduced in the coal as solid.Another embodiment of the method for present disclosure is included in before the coal dustization, and additive is introduced as solid.Can utilize the known useful any method of those skilled in the art that additive is introduced in coal or the stove.

Can advantageously utilize the method for present disclosure, thereby improve the operation in power house.In some applications, the per unit coal can produce more power.In other is used, can reduce the demand of cigarette ash of going out in the stove.In other application, can notice all these advantages.

Embodiment

Provide following examples to be used to explain the present invention.Embodiment is not used in and limits scope of the present invention, and they should be by understanding like this yet.Except as otherwise noted, quantity is weight part or weight percent.

Embodiment 1

The mineral dye of the oxide compound that comprises iron, manganese and copper that can obtain with trade name F-6331-2 from FERRO Corporation is used to make the coal ash deepening.The high calcium brown coal are mixed with 0.01% concentration with additive.Make grey divided combustion and scanning subsequently.Gained scanning is with HSB (tone, saturation ratio, and brightness) model evaluation.Point in the HSB model representation RGB color model, its intention is described consciousness color relation more accurately than RGB, keeps simple computation property simultaneously.HSB allows to represent color with color, tints and shades.Through sample being converted into this electronic color model, can keep the color harmony saturation ratio independent simultaneously with the brightness measured difference of reality.Scanning can be referring among Fig. 1.Measure sample has 44% brightness.

Embodiment 2

The basic embodiment 1 that repeats usually is except using 0.02% additive.Scanning can be referring among Fig. 2.Measurement of Luminance is 37%.

Embodiment 3

The basic embodiment 1 that repeats usually is except using 0.05% additive.Scanning can be referring among Fig. 3.Measurement of Luminance is 27%.

Comparative example's (contrast)

The basic embodiment 1 that repeats usually is not except using additive.Scanning can be referring among Fig. 4.Measurement of Luminance is 68%.

Table

Sample number	Additive, wt%	Brightness %	Change %
				Embodiment 1	0.01	44	35.3
Embodiment 2	0.02	37	45.6
				Embodiment 3	0.05	27	60.3
Contrast	-	68	-

Suppose embodiment

Utilize untreated coal operation by the coal-fired stove driven power station.The variable of record comprises the speed when introducing coal in the stove, the megawatt power of generation and the frequency of " cigarette ash-blowing " in operation.This back one term refers to utilize gas blower from stove, to blow down the process of sedimentary cigarette ash on the boiler tube.After generating is to operate under the steady load, spray on the coal through solution/suspension additive, the additive of embodiment 1 is introduced just being added on the coal in the stove.Additive is being introduced in the stove and allowed the power house to turn back under steady load after the operation, noticing that the per unit coal produces power and each conversion of more megawatts need blowing cigarette ash still less.

Claims

1. thereby be used for handling the method that coal improves the coal-fired stove heat transfer efficiency, said method comprises: before coal combustion or simultaneously, coal is contacted with additive, wherein:

The function of additive is to compare the radiogenic heat absorption that strengthens coal ash with other same procedure that does not have additive; With

Additive does not comprise fusing assistant.

2. the process of claim 1 wherein that additive is the pigment that comprises at least 3 kinds of oxide compounds that are selected from Fe, Cu, Co and Mn oxide compound.

3. the method for claim 2, wherein pigment comprises Fe, Cu and Mn oxide compound.

4. the method for claim 3, wherein pigment comprises the copper oxide of the about 60 weight % (in metal) of about 15-; The Mn oxide of the about 70 weight % (in metal) of about 20-; Ferriferous oxide with the about 30 weight % (in metal) of about 5-.

5. the method for claim 4, wherein pigment comprises the copper oxide of the about 45 weight % (in metal) of about 25-; The Mn oxide of the about 60 weight % (in metal) of about 35-; Ferriferous oxide with the about 25 weight % (in metal) of about 10-.

6. the method for claim 2, wherein pigment comprises Fe, Cu and Co oxide compound.

7. the method for claim 6, wherein pigment comprises the copper oxide of the about 60 weight % (in metal) of about 15-; The cobalt/cobalt oxide of the about 70 weight % (in metal) of about 20-; Ferriferous oxide with the about 30 weight % (in metal) of about 5-.

8. the method for claim 7, wherein pigment comprises the copper oxide of the about 45 weight % (in metal) of about 25-; The cobalt/cobalt oxide of the about 60 weight % (in metal) of about 35-; Ferriferous oxide with the about 25 weight % (in metal) of about 10-.

9. the process of claim 1 wherein that additive is the pigment that comprises Fe, Cu, Co and Mn oxide compound.

10. the method for claim 9, wherein pigment comprises the copper oxide of the about 60 weight % (in metal) of about 15-; The Mn oxide of the about 70 weight % (in metal) of about 20-; The cobalt of the about YY weight of about XX-% (in metal); Ferriferous oxide with the about 30 weight % (in metal) of about 5-.

11. the method for claim 10, wherein pigment comprises the copper oxide of the about 45 weight % (in metal) of about 25-; The Mn oxide of the about 60 weight % (in metal) of about 35-; The cobalt of the about YY2 weight of about XX2-% (in metal); Ferriferous oxide with the about 25 weight % (in metal) of about 10-.

12. the process of claim 1 wherein before burning, additive introduced in the coal.

13. the method for claim 12 wherein sprays additive on the coal.

Make coal dustization and additive is sprayed on the coal before the efflorescence 14. the method for claim 13, wherein said method also comprise.

Make coal dustization and after efflorescence or simultaneously, additive is sprayed on the coal 15. the method for claim 13, wherein said method also comprise.

16. the method for claim 12 is wherein mixed as solid additive with coal.

17. the method for claim 16 is wherein before the efflorescence or simultaneously additive is mixed with coal.

18. the process of claim 1 wherein and simultaneously additive is introduced in the coal at incendiary.

19. the method for claim 19 wherein sprays additive in the stove.

Thereby 20. being used for handling the method that coal improves the coal-fired stove heat transfer efficiency, said method comprises: before coal combustion or simultaneously, coal is contacted with additive, wherein:

The function of additive is the radiogenic heat absorption that strengthens coal ash;

Additive does not comprise fusing assistant; With

Additive is the pigment that comprises at least 3 kinds of oxide compounds that are selected from Fe, Cu, Co and Mn oxide compound.