CN85103521A

CN85103521A - The control method of coal-fired thermal storage boiler

Info

Publication number: CN85103521A
Application number: CN 85103521
Authority: CN
Inventors: 前田利春
Original assignee: Sunflame Seiki KK
Current assignee: Sunflame Seiki KK; SUNFLAME精机株式会社
Priority date: 1985-01-24
Filing date: 1985-05-02
Publication date: 1986-07-23
Also published as: JPS61173004A

Abstract

The invention relates to the control method of coal-fired thermal storage boiler, its purpose is to provide and is suitable for having both that have can be than the control method of the high-performance coal-fired storage boiler of the performance of the more fumy storage heater of specified generation.

The present invention adopts and at ordinary times burning is remained on certain haply degree or it is changed lentamente, changes the formation of confluent simultaneously by the relative inverse proportion of evaporation capacity, so that can be when underload; A large amount of water supply risen pressure and water level, and accumulation energy just reduces the open above-mentioned energy of confluent in a large amount of steam of needs, make it emit a large amount of steam.

This method mainly is applicable to the bigger aspect of load change of steam such as chemical plant.

Description

The control method of coal-fired thermal storage boiler

The invention relates to the control method of coal-fired thermal storage boiler.

All be to supply with water and fuel pro rata, to keep certain water level and certain pressure in general boiler with desired evaporation capacity.

Therefore, with general boiler, it is impossible supplying with the above steam of its rated capacity.

And then coal fired boiler compares with the boiler that burns gas with oil firing, also has the change difficulty of quantity combusted and the shortcoming of incompatibility load change.

Also have, close boiler and steam accumulator as a whole, similarly controlling with above-mentioned boiler at ordinary times makes it carry out work as boiler, improve its pressure and water level standby simultaneously, make it carry out work and produce a large amount of steam as storage heater with regard to stopping to supply water in a large amount of steam of needs, such heat storage boiler is well-known.

Yet because always this well-known heat storage boiler all is burning heavy oil or coal gas, therefore, its quantity combusted also just can be controlled preferably.

And, because heat storage boiler can be transferred to approximately certain degree to quantity combusted, or in long variable cycle, allow on one side its change at leisure, operate on one side, burn the suitable of coal so adopt oil firing or burn gas not as good as adopting, but also do not propose any scheme for the suitableeest control method of coal-fired thermal storage boiler at present.

Purpose of the present invention is intended to solve above-mentioned existing in prior technology shortcoming, provides to be suitable for having both that have can be than the control method of the high-performance coal-fired storage boiler of the performance of the more fumy storage heater of specified generation.

Main points of the present invention are exactly, and at ordinary times burning is remained on certain haply degree or it is changed lentamente, change confluent by the relative inverse proportion of evaporation capacity simultaneously, and in underload, a large amount of water supply makes pressure and water level rise accumulation energy.In a large amount of steam of needs, just reduce the open above-mentioned energy of confluent, make it emit a large amount of steam.

Adopting as above-mentioned formation, just looks like to have obtained the ability same with being equipped with storage heater, also just can be used for supplying with the steam of rated capacity more than 2 times, in addition, also can bring into play original peak efficiency as boiler.

Below, Yi Bian with reference to accompanying drawing, Yi Bian be elaborated with regard to embodiments of the invention.

Fig. 1 and Fig. 2 are the section front elevation and the cross-section side views of an embodiment of expression the present invention's coal-fired thermal storage boiler, and Fig. 3 is this section side, pipe-line system and control circuit figure, Fig. 4 be expression its produce the graph of a relation of quantity of steam and confluent.

In Fig. 1 and Fig. 2, the 1st, preceding runner plate, the 2nd, shell plate, the 3rd, back runner plate, the 4th, little smoke box, 5, the 5th, horizontal smoke pipe, 6, the 6th, water cooled furnace wall pipe, 7, the 7th, downcomer, 8, the 8th, header, the 9th, fixed grate, the 10th, water level interface, the 11st, pressure gauge connection, the 12nd, relief valve connection, the 13rd, main steam valve interface, 14 bleed valve interfaces, the 15th, inlet port (manhole), 16, the 16th, handling becket, the 17th, flue, the 18th, economizer, the 19th, motor, the 20th, attract ventilation blower, the 21st, damper (damper), the 22nd, chimney, the 23rd, base, the 24th, firing machine surface, the 25th, side flue, the 26th, water.These structure elements are applied to coal-fired thermal storage boiler to well-known heat storage boiler.

Moreover burning of coal gas is from the surperficial 24 process flues 25 of firing machine, little smoke box 4 by the attraction ventilation blower 20 of working by the rotation of motor 19, and then be directed to the plural number horizontal smoke pipe 5,5, again by flue 17, economizer 18 is sent to chimney 22 through attracting ventilation blower 20.

By above-mentioned burning of coal gas water 26 is heated and produces steam.This water level then by the adjusting feedwater of following explanation, is regulated in the scope that is controlled at from high water level 26a to low water level 26d.

Below the water supply piping system of employing Fig. 3 and control chart thereof describe with regard to the control method of the present invention's coal-fired thermal storage boiler.

Among Fig. 3 27, the 28th, steam valve, the 29th, steam-flow meter, the 30th, feed meter, 31,31 ' be integrating indicator, the 32nd, microcomputer, 33,34 and 35 is motor valves, the 36, the 37th, float switch, the 38th, boiler pressure gauge.

At first, by integrating indicator to the output signal of steam-flow meter 29 adding up between for example per 1～5 minute of certain cycle, calculate evaporation capacity (ton/hour) by microcomputer 32 again.

The output signal of feed meter 30 also with above-mentioned steam-flow meter 29 equally by integrating indicator 31 ' add up, calculate confluent (ton/hour) by microcomputer again.

Secondly,, suitably control the aperture of motor valve 33, make water supply by carry out inversely proportionally with steam generating amount by microcomputer 32.

So, when boiler produced than steaminess, feedwater just tailed off, and just fed water in a large number when the steam generation is less.

That is to say that boiler feed capacity increases and decreases with inverse proportion according to load change, because boiler also plays a part storage heater, so even load change significantly also can remain on certain limit to the coal combustion amount.

If the water level of boiler reaches peak level 26a, float switch 36 cuts out motor valve 34 with regard to start, and if water level drops to 26b, motor valve 34 just is opened.

If the water level of boiler drops to dangerous low water level 26d, motor valve 35 is just opened to prevent to burn empty, also has, and its water level is as rising to 26c, and motor valve 35 just cuts out, and stops feedwater, and disengagement area in the boiler is not reduced to below certain feasible value.

And when being up to minimum mid water levels, motor valve 33 just keeps suitable aperture according to the instruction of microcomputer 32, makes it carry out suitable feedwater according to the increase and decrease that steam produces.

The indicated value of boiler pressure gauge 38 input microcomputer 32, lump together with the data of steam-flow meter 29 and feed meter 30, make it revise calculation according to boiler pressure.That is to say,, just increase confluent, otherwise the indicated value of boiler pressure gauge 38 drops to the following words of setting value and just reduces confluent if the indicated value of boiler pressure gauge 38 rises to more than the setting value.

Fig. 4 is the schematic diagram of the relation of above-mentioned generation quantity of steam of expression and confluent, the passing of the confluent of expression dotted line and the quantity of steam of solid line.

Like this, process according to the invention, as mentioned above, just reduce feedwater with evaporation capacity in the time of excess load inversely proportionally, otherwise, in light load, just feed water in a large number, just can at any time deal with significantly anxious strong load change by a large amount of hot water of possessing as the boiler of storage heater work itself. And burning therebetween also can often remain on certain degree, the high efficiency that the performance boiler is original.

Of the present invention constituting as above-mentioned implemented when of the present invention, can provide to be suitable for having concurrently the control method that produces more than the high-performance coal-fired storage boiler of the performance of specified more fumy storage heater.

Also have, structure of the present invention is not limited to the above embodiments, and each shape, specification etc. of constructing element also can design in the scope of purpose of the present invention freely and change, and the present invention is all included these.

Fig. 1 and Fig. 2 are the section front elevation and the cross-section side views of an embodiment of expression the present invention's coal-fired thermal storage boiler;

Fig. 3 is the pipe-line system and the control circuit figure of this section side;

Fig. 4 is the schematic diagram of the relation of this generation quantity of steam of expression and confluent.

1 ... preceding runner plate

2 ... shell plate

3 ... back runner plate

4 ... little smoke box

5,5 ... horizontal smoke pipe

6,6 ... the water cooled furnace wall pipe

7,7 ... downcomer

8,8 ... header

9 ... fixed grate

13 ... the main steam valve interface

17 ... flue

18 ... economizer

19 ... motor

20 ... attract ventilation blower

21 ... damper

22 ... chimney

26 ... water

26a ... high water level

26d ... low water level

29 ... steam-flow meter

30 ... feed meter

31,31 ' ... integrating indicator

32 ... microcomputer

33,34,35 ... motor valve

36,37 ... float switch

38 ... boiler pressure gauge

Claims

The feature of coal-fired thermal storage boiler control method is: make boiler often keep certain burning, supply water with the evaporation capacity that is required also can be at any time according to the variable supply steam of loading approximately inversely proportionally.