CN102777886A - Flue gas waste heat recovery device and method for gas-fired boiler - Google Patents
Flue gas waste heat recovery device and method for gas-fired boiler Download PDFInfo
- Publication number
- CN102777886A CN102777886A CN2012102868325A CN201210286832A CN102777886A CN 102777886 A CN102777886 A CN 102777886A CN 2012102868325 A CN2012102868325 A CN 2012102868325A CN 201210286832 A CN201210286832 A CN 201210286832A CN 102777886 A CN102777886 A CN 102777886A
- Authority
- CN
- China
- Prior art keywords
- flue gas
- saving appliance
- boiler
- gas energy
- resistance
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Landscapes
- Control Of Steam Boilers And Waste-Gas Boilers (AREA)
Abstract
The invention provides a flue gas waste heat recovery method for a gas-fired boiler. The flue gas waste heat recovery method mainly comprises the following steps: 1) determining the difference between the furnace pressure of the boiler and the resistance at the flue gas side in a convection chamber arranged on the boiler; 2) determining the exhaust gas temperature and return water temperature of the boiler; 3) controlling the inside resistance of a flue gas economizer to be less than or equal to the difference between the furnace pressure of the boiler and the resistance at the flue gas side in the convection chamber; and 4) controlling the water inflow so that the return water temperature meets the requirement. The invention further discloses a device used for realizing the method. According to the device and the method, in comprehensive consideration of the matching relation between the boiler and the flue gas economizer, the waste heat recovery efficiency of the gas-fired boiler can be improved and adverse effects on the boiler are prevented.
Description
Technical field
The present invention relates to a kind of gas fired-boiler flue gas waste heat recovery method.
The invention still further relates to a kind of device that is used to realize said method.
Background technology
The natural gas heat that discharges that in boiler, burns can all not be employed, and will produce part loss inevitably.Wherein flue gas loss is one maximum in each item heat loss.The exhaust gas temperature of boiler is generally at 120-180 ℃, and the contained great amount of heat of flue gas is made up of two parts, and a part is the physics sensible heat, and this heat can reclaim through reducing the cigarette temperature, and exhaust gas temperature is reduced to below 70-100 ℃, can improve boiler thermal output.Second portion is the latent heat of vaporization, and this heat can reclaim through the phase transformation that water vapour is condensed into water, also can improve boiler thermal output.It is thus clear that the boiler exhaust gas very big waste heat source that is potentiality.
How to reduce smoke discharging residual heat, the heat loss that reducing discharges fume brings becomes one of subject matter of boiler technology personnel research.The mode of gas fired-boiler flue gas waste heat recovery at present has multiple, and many is to install the flue gas energy-saving appliance additional.But because when installing the flue gas energy-saving appliance additional; Do not take all factors into consideration blast, the furnace pressure of pressure fan under boiler chimney draft, the operation conditions; And the factors such as variation of exhaust gas temperature; Therefore it is not high to install flue gas energy-saving appliance waste heat recovery efficient afterwards additional, and boiler occurs vibration easily and produces noise.
Summary of the invention
The object of the present invention is to provide a kind of gas fired-boiler flue gas waste heat recovery method.
Another purpose of the present invention is to provide a kind of device that is used to realize said method.
Be the realization above-mentioned purpose, gas fired-boiler flue gas waste heat recovery method provided by the invention, its main process is:
1) difference in the convection cell of confirming to install on furnace pressure and the boiler of boiler between the fume side resistance;
2) confirm exhaust gas temperature and return water temperature;
3) collateral resistance is less than or equal to the difference between the fume side resistance in furnace pressure and the convection cell in the control flue gas energy-saving appliance;
4) the control inflow makes return water temperature reach requirement.
Described method, wherein, collateral resistance is less than the difference between the fume side resistance in furnace pressure and the convection cell in the control flue gas energy-saving appliance.
Described method, wherein, the control system of flue gas energy-saving appliance is for independently controlling system.
Described method, wherein, the control system of flue gas energy-saving appliance keeps watch on and controls inflow, backwater amount, exhaust gas temperature, smoke evacuation pressure and smoke evacuation flow.
The device that is used to realize said method provided by the invention is provided with the flue gas energy-saving appliance on the smokejack of boiler, the control valve of a control inflow is installed on the inlet channel of flue gas energy-saving appliance.
Described device, wherein, the inlet channel of flue gas energy-saving appliance is connected to the female pipe of water supply of boiler, and the outlet conduit of flue gas energy-saving appliance is connected to the female pipe of backwater of boiler.
Described device, wherein, the control valve of flue gas energy-saving appliance is a motor-driven valve.
Described device, wherein, the flue gas energy-saving appliance is the steel aluminium composite pipe formula flue gas energy-saving appliance of arranging along row, and flue gas energy-saving appliance body is provided with a damper, resistance that can free adjustment flue gas energy-saving appliance fume side.All heating surfaces reach with the flue gas contact site of smoke evacuation and all do preservative treatment.
Because the present invention takes all factors into consideration the matching relationship between boiler and the flue gas energy-saving appliance, therefore can improve the waste heat recovery efficient of gas fired-boiler, and can avoid boiler is produced adverse consequences.
Description of drawings
Fig. 1 is a device sketch map of the present invention.
The specific embodiment
The boiler of below lifting Shuangyushu heat supply factory, Beijing is an example, and the present invention is further described.
4 gas fired-boilers of Shuangyushu heat supply factory, Beijing, the heat capacity of every hot-water boiler is 116MW, and exhaust gas temperature is 160 ℃, and leaving water temperature is 150 ℃, and inflow temperature is 40-70 ℃, boiler pressure is 2.5Mpa.
The present invention has installed a flue gas energy-saving appliance on the smokejack of boiler, backwater is got into by the end of flue gas energy-saving appliance next part case, brings out from another of upper collecting chamber, becomes the Z font to flow on the whole.Circling water flow rate is 200t/h.In order to control the discharge of flue gas energy-saving appliance, on the inlet channel of flue gas energy-saving appliance, adorned an electric control valve.The inlet channel of flue gas energy-saving appliance is connected respectively on the water supply mother pipe and the female pipe of backwater that is connected on the boiler room with outlet conduit, gets into the flue gas energy-saving appliance from the female water that comes of managing of backwater, after flue gas heating, flows into female pipe of supplying water.Output through the control valve on the flue gas energy-saving appliance inlet channel is controlled exhaust gas temperature, keeps exhaust gas temperature about 80 ℃.For fear of the original boiler control system of influence, so the control system of flue gas energy-saving appliance separates with former boiler control system.The control system keeps watch on and controls all data such as the temperature that supplies backwater and cigarette temperature, pressure, flows.Such arrangement, minimum to boiler operatiopn and the influence of former heating system, also be more energy-conservation mode.
Flue gas energy-saving appliance of the present invention is known steel aluminium composite pipe formula flue gas energy-saving appliance, and all heating surfaces reach with flue gas and contact local preservative treatment, arranges along row.
The highest blast 7000Pa of the boiler fan of Shuangyushu heat supply factory, the boiler chimney draft is about 180-214Pa.The blast of pressure fan is 4810Pa under the general operation conditions, and furnace pressure is 1800Pa.Because boiler producer does not provide the resistance of fume side in the convection cell, therefore need to calculate the resistance of fume side in the convection cell.Through calculating, the resistance of fume side is about 1000Pa (calculation of resistance of fume side is a techniques well known in the convection cell) in the boiler convection cell of Shuangyushu heat supply factory.
Data according to the resistance of fume side in above furnace pressure and the convection cell; The resistance of flue gas energy-saving appliance side of the present invention is controlled at 240Pa (less than the difference 800Pa of fume side resistance in furnace pressure and the convection cell); The present invention also is provided with a damper at flue gas energy-saving appliance body, to regulate the resistance of flue gas energy-saving appliance fume side.Discharge flue gas and come out through convection cell from burner hearth, get into chimney through the flue gas energy-saving appliance again, needed pressure can be satisfied by the pressure head of pressure fan.
The boiler smoke exhaust gas temperature is 160 ℃, and after installing the flue gas energy-saving appliance on the flue additional, flue gas energy-saving appliance porch and flue-gas temperature are 125 ℃, can be reduced to 85 ℃ through temperature behind the flue gas energy-saving appliance, is higher than 50 ℃ of the dew-point temperatures of flue gas far away.So flue gas only can produce a spot of condensed water, and condensation water quantity can be very not big.
Because flue gas energy-saving appliance body resistance of the present invention less (240Pa) is very little for the influence of burner, so boiler combustion system is no problem.
The flue gas energy-saving appliance can produce condensate generally speaking, and condensate is faintly acid, contains a large amount of iron ions, can not utilize again.If boiler operatiopn is talked about normally, condensing capacity is little, therefore reclaims to have little significance, as long as it is just passable to reach discharge standard.Technological process is a known technology.
Amount of energy saving of the present invention calculates:
Adopt gas component to see shown in the table 1 during design.
The sensible heat uptake is seen shown in the table 2 in the flue gas.
The latent heat heat that steam condenses in the flue gas:
According to pertinent literature, can learn that the steam different shares of condensing cause that the parameter of raising value of boiler thermal output is as shown in table 3.Design considers that the condensed water according to 10% condenses, and heat that condensed water produces is 1218kW, multiply by heat exchanger efficiency 95% again, i.e. 1157.1kW.
Separate unit energy-saving appliance heat is 2296.055+1157.1=3453.155kW
Through design, separate unit flue gas energy-saving appliance parameter is as shown in table 4.
Table 1
| CH 4 | 95.95 | CO | - |
| C 2H 6 | 0.91 | CO 2 | 3.0 |
| C 3H 8 | - | N 2 | - |
| C 4H 10 | - | O 2 | - |
| C 4H 8 | - | H 2S | 0.002 |
| C 3H 6 | 0.14 | Density (kg/Nm 3) | 0.76 |
| Other (CmHn) | - | Low heat value (kJ/Nm 3) | 35160 |
| H 2 | - | (Wobbe index MJ/Nm 3) | 50.0 |
Smoke evacuation place excess air coefficient α py=1.15
Table 2
| The temperature of flue gas | ℃ | Known | 125 |
| Gas quantity | N，m 3/h | 12502 | |
| The exhaust gas volumn that every cube of combustion gas produced | N，m 3/h | 11.874 | |
| Exhaust gas volumn | m 3/h | Known (mark condition) | 148451.5 |
| The exhanst gas outlet temperature | ℃ | 85 | |
| The mean temperature of flue gas | ℃ | 105 | |
| Specific heat at constant pressure | kJ/kg℃ | 1.1109 | |
| Density | kg/m 3 | 1.319 | |
| Thermal conductivity factor | W/m℃ | 0.037 | |
| Viscosity | kg/ms | 2.62E-05 | |
| Pulan moral number | PR | 0.68 | |
| The flue gas thermal discharge | kJ/h | 8700904.977 | |
| Convert | kW | 2416.9 | |
| The water caloric receptivity | kW | ×0.95 | 2296.055 |
Table 3
Table 4
Claims (10)
1. gas fired-boiler flue gas waste heat recovery method, its main process is:
1) difference in the convection cell of confirming to install on furnace pressure and the boiler of boiler between the fume side resistance;
2) confirm exhaust gas temperature and return water temperature;
3) collateral resistance is less than or equal to the difference between the fume side resistance in furnace pressure and the convection cell in the control flue gas energy-saving appliance;
4) the control inflow makes return water temperature reach requirement.
2. method according to claim 1, wherein, collateral resistance is less than the difference between the fume side resistance in furnace pressure and the convection cell in the control flue gas energy-saving appliance.
3. method according to claim 1, wherein, the control system of flue gas energy-saving appliance is for independently controlling system.
4. method according to claim 3, wherein, the control system of flue gas energy-saving appliance keeps watch on and controls inflow, backwater amount, exhaust gas temperature, smoke evacuation pressure and smoke evacuation flow.
5. a device that is used to realize the said method of claim 1 is provided with the flue gas energy-saving appliance on the smokejack of boiler, and the control valve of a control inflow is installed on the inlet channel of flue gas energy-saving appliance.
6. device according to claim 5, wherein, the inlet channel of flue gas energy-saving appliance is connected to the female pipe of water supply of boiler, and the outlet conduit of flue gas energy-saving appliance is connected to the female pipe of backwater of boiler.
7. device according to claim 5, wherein, the control valve of flue gas energy-saving appliance is a motor-driven valve.
8. device according to claim 5, wherein, the flue gas energy-saving appliance is the steel aluminium composite pipe formula flue gas energy-saving appliance of arranging along row, and flue gas energy-saving appliance body is provided with a damper, to regulate the resistance of flue gas energy-saving appliance fume side.
9. according to claim 5 or 8 described devices, wherein, all heating surfaces of flue gas energy-saving appliance reach with the flue gas contact site of smoke evacuation and all do preservative treatment.
10. device according to claim 8, wherein, the damper of flue gas energy-saving appliance is the motorized adjustment air door.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210286832.5A CN102777886B (en) | 2012-08-13 | 2012-08-13 | Flue gas waste heat recovery device and method for gas-fired boiler |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210286832.5A CN102777886B (en) | 2012-08-13 | 2012-08-13 | Flue gas waste heat recovery device and method for gas-fired boiler |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102777886A true CN102777886A (en) | 2012-11-14 |
| CN102777886B CN102777886B (en) | 2014-07-16 |
Family
ID=47122903
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210286832.5A Active CN102777886B (en) | 2012-08-13 | 2012-08-13 | Flue gas waste heat recovery device and method for gas-fired boiler |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102777886B (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09242509A (en) * | 1996-03-07 | 1997-09-16 | Mitsubishi Heavy Ind Ltd | Power generating plant provided with feed water heater using exhaust gas |
| CN2438927Y (en) * | 2000-09-25 | 2001-07-11 | 中日青年交流中心 | Flue heat exchanger |
| EP0909922B1 (en) * | 1997-10-17 | 2002-01-09 | Riello S.p.a. | Combined gas-air control system for controlling combustion in gas fired boilers |
| CN201003783Y (en) * | 2007-02-05 | 2008-01-09 | 张学林 | High-performance energy-saving environmental protection boiler residual heat recovering device |
| CN201074826Y (en) * | 2007-07-27 | 2008-06-18 | 贺军 | Flue gas/oil-fired boiler energy conservation equipment |
| CN201255417Y (en) * | 2008-04-28 | 2009-06-10 | 侯光林 | Flue condensation economizer |
| CN101520172A (en) * | 2009-04-03 | 2009-09-02 | 上海晟煜科贸有限公司 | Energy-saving reclaiming process for residual heat of fume in boiler |
-
2012
- 2012-08-13 CN CN201210286832.5A patent/CN102777886B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09242509A (en) * | 1996-03-07 | 1997-09-16 | Mitsubishi Heavy Ind Ltd | Power generating plant provided with feed water heater using exhaust gas |
| EP0909922B1 (en) * | 1997-10-17 | 2002-01-09 | Riello S.p.a. | Combined gas-air control system for controlling combustion in gas fired boilers |
| CN2438927Y (en) * | 2000-09-25 | 2001-07-11 | 中日青年交流中心 | Flue heat exchanger |
| CN201003783Y (en) * | 2007-02-05 | 2008-01-09 | 张学林 | High-performance energy-saving environmental protection boiler residual heat recovering device |
| CN201074826Y (en) * | 2007-07-27 | 2008-06-18 | 贺军 | Flue gas/oil-fired boiler energy conservation equipment |
| CN201255417Y (en) * | 2008-04-28 | 2009-06-10 | 侯光林 | Flue condensation economizer |
| CN101520172A (en) * | 2009-04-03 | 2009-09-02 | 上海晟煜科贸有限公司 | Energy-saving reclaiming process for residual heat of fume in boiler |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102777886B (en) | 2014-07-16 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN100402814C (en) | Smoke low-temperature residual heat utilization system with natural gas cooling-heating combined power device and operating method thereof | |
| CN204254934U (en) | A kind of heating system utilizing compression heat pump to realize the recovery of the residual heat from boiler fume degree of depth | |
| CN104763485B (en) | A kind of concurrent heating type ultrahigh pressure/subcritical back pressure thermal power plant unit thermodynamic system | |
| CN105157010A (en) | Coal-fired power generation system based on bypass flue at tail part of boiler | |
| CN106996571A (en) | A kind of coal-fired hot-water boiler fume afterheat depth recovery system and its method | |
| WO2011020333A1 (en) | System for recovering waste heat from flue gas | |
| CN105793653B (en) | heat exchanger for heating boiler | |
| WO2011020334A1 (en) | System for recovering waste heat from flue gas | |
| CN105698161B (en) | Coal fired power plant level-density parameter around First air is thermally integrated system | |
| CH700750A1 (en) | System for the production of thermal energy. | |
| RU2440538C1 (en) | Outside condensation boiler | |
| CN106322427A (en) | Deslagging waste heat utilization system and deslagging waste heat utilization method for circulating fluidized bed boiler | |
| CN202166034U (en) | Vapor generator for heat pipes | |
| CN104501397A (en) | Membrane water-wall compound return water condensing type natural gas hot water boiler | |
| CN102252311B (en) | Flue gas heat exchange device of oil field gas injection boiler and heat exchange method thereof | |
| CN102330966B (en) | Energy-saving heat-supplying device of condensation steam boiler | |
| CN104501608A (en) | Equipment and method for superheating saturated steam of heating furnace by waste heat of large sintering flue | |
| CN107062296A (en) | One kind prevents station boiler low-temperature corrosion system | |
| CN102777886B (en) | Flue gas waste heat recovery device and method for gas-fired boiler | |
| CN109780529A (en) | A kind of biomass cogeneration of heat and power operation method mixing water heat supply based on end electric heating pump | |
| CN109489255A (en) | A kind of flue gas condensing heat recovery apparatus | |
| CN209945054U (en) | System device for changing water cooling of condenser of steam turbine generator unit into air cooling | |
| CN203533668U (en) | System for fume deep-cooling heat recovery of combined cycle gas turbine unit | |
| CN107345656A (en) | A kind of steam raising plant using residual heat from boiler fume | |
| CN107101374A (en) | A kind of method that non-condensing wall-hung boiler changes deep condensation wall-hung boiler |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CP01 | Change in the name or title of a patent holder |
Address after: 100089 No. 5 North Road, West Third Ring Road, Haidian District, Beijing. Co-patentee after: Beijing District Heating Group Co., Ltd. Patentee after: China Zhong Yuan international project company limited Address before: 100089 No. 5 North Road, West Third Ring Road, Haidian District, Beijing. Co-patentee before: Beijing District Heating Group Co., Ltd. Patentee before: China Ippr International Engineering Co., Ltd. |
|
| CP01 | Change in the name or title of a patent holder |