CN2898630Y

CN2898630Y - Automatic energy-saving control system of mini-medium fired-coal chain boiler

Info

Publication number: CN2898630Y
Application number: CN 200620072828
Authority: CN
Inventors: 陆磊
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-04-22
Filing date: 2006-04-22
Publication date: 2007-05-09
Anticipated expiration: 2016-04-22

Abstract

The utility model discloses an automatic energy-saving control system of mini-medium fired-coal chain boiler belonging to automatic control device of boiler. The utility model comprises an industrial programmable controller, a plurality of sensors used to collect the real-time running signals of a boiler and a displaying part of driving and running. The real-time running signals of the boiler are transmitted to the controller. The controller compares the signals with the set signals of best state and drives an actuator to control the running state of the boiler. The system makes boilers save coal and electricity and have long life-span.

Description

Middle-size and small-size combustion coal chain boiler energy-saving automatic control system

Technical field

The utility model belongs to the Automatic Control of Boiler field.Specifically a kind of middle-size and small-size combustion coal chain boiler energy-saving automatic control system.

Background technology

At present, the overall price of coal-fired chain industry boiler is lower below 35 tons, so electric-control system did not possess intelligence control system when the boiler of this type dispatched from the factory, only satisfy manually-operated requirement, in the operation of reality, because stoker workman's quality difference is subjected to the influence of factors such as psychology, health, night shift again, cause boiler can not operate in optimum state, cause the hot working efficiency of boiler only can reach 50%-60%.Differ very big with the 70%-75% of national regulation, wasted a large amount of coal resources.

The general boiler controller of part can finished or local control is only arranged on the market now, but can not finish all work such as signals collecting, control automatically, driving, this quasi-controller is normally finished by single-chip microcomputer, individual less, function singleness, very flexible can not self-organizing system.Adopt self-control SCM system or industrial computer system in addition, can't satisfy under the boiler room rugged environment and move, only be 2 years average non-failure operation time.

Summary of the invention

The purpose of this utility model provides a kind of middle-size and small-size combustion coal chain boiler energy-saving automatic control system, to realize automatic control to combustion coal chain boiler below 35 tons, improve fire box temperature and feed temperature, reduce the phosphorus content of exhaust gas temperature and slag, realize economizing on coal electricity-saving function.The while long service life.

The utility model is realized with following technical scheme: a kind of middle-size and small-size combustion coal chain boiler energy-saving automatic control system, it is characterized in that: it comprises programmable controller, gather the level sensor of the high extremely low state of boiler drum water level, gather the boiler drum water level sensor of real-time actual boiler drum water level, gather the steam flow sensor of real-time steam flow, gather the steam pressure sensor of real-time drum steam pressure, gather the combustion chamber draft sensor of real-time combustion chamber draft, gather the fire box temperature sensor of real-time fire box temperature, gather the flue temperature sensor of real-time flue temperature, gather cooling-water temperature sensor after the province of economizing the back water temperature in real time, above-mentioned each sensor is electrically connected with the input of Programmable Logic Controller respectively, and the signal of gathering is flowed to Programmable Logic Controller; It also comprises air-introduced machine frequency converter, blower variable frequency device, feed pump frequency converter, fire grate frequency converter and fault alarm, the operating desk of the control boiler operatiopn that is electrically connected with the I/O interface of Programmable Logic Controller.

Its operation principle is: each sensor is with the parameters input controller of the boiler of collection, by controller the parameter and the predefined optimum working parameter of input are compared, control the operation of air-introduced machine, air blast, feed pump, fire grate then, with continuous adjusting coal supply, make boiler keep burning stable, that continue for wind, feedwater, the waste that reduces excessive coal supply, causes to wind.

The utility model has the advantages that: systemic-function is complete, can finish whole signals collecting, control drives automatically.Economize on coal, economize on electricity, mean free error time be more than 10 years.

Description of drawings

Below in conjunction with drawings and Examples the utility model is described in further detail.

Fig. 1 is the utility model system architecture block diagram;

Fig. 2 is system's burning control flow chart;

Fig. 3 is system's feedwater control flow chart;

Fig. 4 is system's negative pressure control flow chart;

Fig. 5 is the operating desk layout drawing;

Fig. 6 is the key frame that system's operation shows;

Fig. 7 is that the parameter that system's operation shows is provided with picture.

Among the figure: 1, the water-level alarm sensor, 2, level sensor, 3, the steam flow sensor, 4, the steam pressure sensor, 5, the combustion chamber draft sensor, 6, the fire box temperature sensor, 7, economize the back cooling-water temperature sensor, 8, the flue temperature sensor, 9, Programmable Logic Controller, 10, operating desk, 11, touch-screen, 12, fault alarm, 13, other executing agencies, 14, the fire grate frequency converter, 15, the feed pump frequency converter, 16, the blower variable frequency device, 17, the air-introduced machine frequency converter, 18, air-introduced machine, 19, air blast, 20, give hydroelectric machine, 21, fire grate, 22, back-up system.

The specific embodiment

As shown in Figure 1, the sensor that native system is gathered each real-time running state signal of boiler comprises: boiler drum water level alarm sensor 1, and the collection drum is high, utmost point low water level signal is used for reporting to the police; Water level sensor for boiler 2 adopts inductance ball float level sensor, is used to gather the real-time actual water level of drum; Steam flow sensor 3 is used to gather the real-time steam flow; Steam pressure sensor 4 is used to gather real-time drum steam pressure; Combustion chamber draft sensor 5 is used to gather real-time combustion chamber draft; Fire box temperature sensor 6 adopts thermocouple sensor, is used to gather real-time fire box temperature; Economize back level sensor 7 and select thermocouple sensor for use, be used to gather water temperature after the real-time province; Flue temperature sensor 8 is selected the thermocouple sensor for use, is used to gather real-time flue temperature.Controller 9 adopts industrial Programmable Logic Controller Siemens S7-200PLC.Above-mentioned each sensor all is electrically connected each real time information of carrying the boiler of gathering to controller with the input port of controller 9.The I/O interface of Programmable Logic Controller is respectively by frequency converter 14,15,16,17 and fire grate 21, be electrically connected to hydroelectric machine 20, blower motor 19, blower motor 18.In controller, store as Fig. 2, Fig. 3, working procedure shown in Figure 4.

Operating desk 10 layout drawings as shown in Figure 5, table top is rationally distributed, is convenient to operation.

As Fig. 6, shown in Figure 7, display frame and parameter when system's operation is arranged on the touch-screen 11 are provided with picture.

Its control principle is: each sensor is given programmable controller with the real-Time Signal Transfer of gathering, and the data of Programmable Logic Controller and setting relatively drive each actuating mechanism controls boiler operatiopn in optimum state with result.

Its electricity principle of economizing on coal is:

The principle of economizing on coal:

(1) improves burning of coal efficient

Coal-burning boiler is by control automatically, coal is fully burnt, promptly steam pressure, flow, coal amount, fire box temperature, exhaust gas temperature, flue gas oxygen content are carried out analysis-by-synthesis and optimizing adjustment, to reach the effect of the unapproachable approximate ideal of manually-operated according to load condition.Simultaneously can also be according to the quality of ature of coal, factor appropriate changes such as humidification degree are adjusted parameter to reach the best combustion operating mode.Make coal input quantity, the all-round excellent configuration of intake, coal fully burns at furnace front, reduces the carbon content of slag greatly.

(2) changing discontinuous combustion is continuous burning

Coal-burning boiler is when artificial stoker, and the burning of boiler is in the discontinuous combustion state, when vapour pressure hang down, opens air inducing, air blast, quickening fire grate speed; When vapour pressure is high, stop air inducing, air blast, fire grate, the burning that makes boiler off and on.Technology fireman preferably can reduce on-off state by regulating feedwater, but can't really realize sustained combustion because of regulating intake.And manually also can not regulate coal supply constantly, give wind, feedwater.

After coal-burning boiler adopted control automatically, controller was constantly regulated coal supply, is given wind, feedwater according to steam pressure, steam flow, fire box temperature, boiler drum water level, feed temperature, exhaust gas temperature, made boiler reach burning stable, that continue.The waste of reduce excessive coal supply, giving wind.

(3) realize best wind coal proportion

Though when artificial stoker coal supply what, all adopt the identical blow rate required and air inducing amount, cause wind coal proportion improper, be unfavorable for the economical combustion of coal.

After adopting control automatically, system can constantly adjust drum, air inducing amount according to different coal-supplying amounts, keeps optimum wind coal proportion.

(4) operating efficiency of raising economizer

When artificial stoker, intake and open water pump when normally water level is low, with prestissimo (water pump power frequency operation) water inlet, stop water pump after arriving predetermined water level, economizer can't play one's part to the full like this.

After adopting control automatically, controller is regulated pump rotary speed according to the steam flow size by frequency converter, keeps continuing water inlet, has water to flow in the economizer always, has improved the heat exchanger effectiveness of economizer, makes the boiler feed water temperature improve 10-20 degree centigrade.

(5) reduce the heat that air-introduced machine is taken away.

Air blast, air-introduced machine have only a kind of speed when artificial stoker, no matter coal supply what, vapour pressure height blower fan can only be with a kind of speed operations, excessive air inducing has been taken away a large amount of heats, reduced furnace temperature, after adopting control automatically, blower fan adopts frequency control, regulates air quantity automatically according to different operating modes, significantly reduces the heat that air-introduced machine is taken away.Flue temperature on average reduces 20-30 degree centigrade.

Electricity principle:

In order to guarantee that boiler can both move in various operating modes, the type selecting of blower fan and capacity motor is bigger usually in boiler design.The adjusting of drum, air-introduced machine by manually according to actual needs controllable register realize, usually drum, the about 50-80% of air-introduced machine baffle opening, though baffle opening is turned down, motor speed is constant, so the blower fan power consumption changes not quite, energy loss is big, fan efficiency is low.

Regulate with frequency control and to replace the throttling of original wind (valve) door and regulate, when institute's required airflow reduced, motor speed slowed down, and power consumption will decline to a great extent.Save electric power on the one hand, stablized adjustable air quantity for boiler provides on the other hand, helped the stable operation of boiler, also played the effect of protection blower fan, motor simultaneously.

After motor reduced rotating speed, power consumption can significantly reduce, and for example: calculate by formula, motor speed reduces by 10%, and power consumption descends 27.5%.So the boiler energy-saving efficiency is considerable.

Claims

1, a kind of middle-size and small-size combustion coal chain boiler energy-saving automatic control system, it is characterized in that: it comprises Programmable Logic Controller (9), the collection boiler drum water level is high, the boiler drum water level alarm sensor (1) of extremely low state, gather the boiler drum water level sensor (2) of real-time actual boiler drum water level, gather the steam flow sensor (3) of real-time steam flow, gather the steam pressure sensor (4) of real-time drum steam pressure, gather the combustion chamber draft sensor (5) of real-time combustion chamber draft, gather the fire box temperature sensor (6) of real-time fire box temperature, gather the flue temperature sensor (8) of real-time flue temperature, gather cooling-water temperature sensor (7) after the province of economizing the back water temperature in real time, above-mentioned each sensor is electrically connected the signal that will gather respectively and flows to Programmable Logic Controller (PLC) (9) with the input of Programmable Logic Controller; It also comprises air-introduced machine frequency converter (17), blower variable frequency device (16), feed pump frequency converter (15), fire grate frequency converter (14) and fault alarm (12), operating desk (10) and the display part of the control boiler operatiopn that is electrically connected with the I/O interface of Programmable Logic Controller (9).

2, a kind of middle-size and small-size combustion coal chain boiler energy-saving automatic control system according to claim 1 is characterized in that: boiler drum water level alarm sensor (1) adopts the electrode level sensor; The boiler drum water level sensor adopts inductance ball float level sensor; Fire box temperature sensor (6), flue temperature sensor (8) and province's back cooling-water temperature sensor (7) all adopt thermocouple sensor.