CN114632417B - Denitration ammonia supply automatic regulating system with accurate feedforward signal - Google Patents
Denitration ammonia supply automatic regulating system with accurate feedforward signal Download PDFInfo
- Publication number
- CN114632417B CN114632417B CN202210262324.7A CN202210262324A CN114632417B CN 114632417 B CN114632417 B CN 114632417B CN 202210262324 A CN202210262324 A CN 202210262324A CN 114632417 B CN114632417 B CN 114632417B
- Authority
- CN
- China
- Prior art keywords
- ammonia
- regulator
- output value
- ammonia supply
- demand
- 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.)
- Active
Links
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 title claims abstract description 208
- 229910021529 ammonia Inorganic materials 0.000 title claims abstract description 104
- 230000001105 regulatory effect Effects 0.000 title claims abstract description 22
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims abstract description 11
- 239000003546 flue gas Substances 0.000 claims abstract description 11
- XKMRRTOUMJRJIA-UHFFFAOYSA-N ammonia nh3 Chemical compound N.N XKMRRTOUMJRJIA-UHFFFAOYSA-N 0.000 claims description 6
- 238000006243 chemical reaction Methods 0.000 claims description 4
- 230000000694 effects Effects 0.000 abstract description 3
- 238000000034 method Methods 0.000 description 7
- 238000002347 injection Methods 0.000 description 3
- 239000007924 injection Substances 0.000 description 3
- 239000000243 solution Substances 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 239000000779 smoke Substances 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
- B01D53/86—Catalytic processes
- B01D53/8621—Removing nitrogen compounds
- B01D53/8625—Nitrogen oxides
- B01D53/8631—Processes characterised by a specific device
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
- B01D53/34—Chemical or biological purification of waste gases
- B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
- B01D53/86—Catalytic processes
- B01D53/8696—Controlling the catalytic process
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2258/00—Sources of waste gases
- B01D2258/02—Other waste gases
- B01D2258/0283—Flue gases
Landscapes
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Biomedical Technology (AREA)
- Analytical Chemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Treating Waste Gases (AREA)
Abstract
The embodiment of the application discloses denitration ammonia supply automatic regulating system of accurate feedforward signal in area relates to coal-fired unit flue gas SCR denitration technical field, its technical scheme include main regulator, with the auxiliary regulator that main regulator links to each other, with feedforward signal calculation module that auxiliary regulator links to each other and with the ammonia supply volume governing valve that auxiliary regulator's output links to each other. According to the embodiment of the application, the automatic denitration ammonia supply adjusting effect can be improved when the load of the coal-fired unit changes, the full-working-condition ammonia supply automatic operation is realized, the participation degree of operators is reduced, the accurate control of ammonia supply parameters is realized, and the NOx concentration of a denitration outlet is ensured to be in a controllable range.
Description
Technical Field
The application relates to the technical field of flue gas SCR denitration of coal-fired units. In particular to a denitration ammonia supply automatic regulating system with an accurate feedforward signal.
Background
At present, the automatic control method for denitration and ammonia supply of the coal-fired unit mainly controls the ammonia injection amount through cascade PID calculated by the ammonia nitrogen molar ratio. When the load of the coal-fired unit is stable and the coal-fired unit operates in a small range of fluctuation, the denitration ammonia supply can automatically operate well. However, when the unit changes working conditions, ammonia supply adjustment is insensitive, deviation generated by vibration cannot be eliminated, an automatic adjustment system automatically exits, and the control effect is not ideal. In order to keep the denitration ammonia supply automatic regulating system in a controllable range, the concentration of NOx at an outlet can still be well regulated under the working condition of load fluctuation, and an accurate feedforward signal is required to be introduced.
Disclosure of Invention
In view of this, the embodiment of the application provides a denitration ammonia supply automatic regulating system with accurate feedforward signal, and under the operating mode of load fluctuation, the outlet NOx concentration can still be fine adjusted within the controllable scope.
The embodiment of the application provides a denitration ammonia supply automatic regulating system with accurate feedforward signals, which comprises a main regulator, an auxiliary regulator connected with the main regulator, a feedforward signal calculation module connected with the auxiliary regulator and an ammonia supply regulating valve connected with the output end of the auxiliary regulator.
According to a specific implementation of an embodiment of the present application, the main regulator is used to detect the concentration of outlet NOx.
According to a specific implementation manner of the embodiment of the application, the auxiliary regulator is used for detecting the actual ammonia supply flow, and the output value of the auxiliary regulator is sent to the ammonia supply amount regulating valve.
According to a specific implementation manner of the embodiment of the present application, the output value of the secondary regulator is a product of the output value of the primary regulator and the output value of the feedforward signal calculating module.
According to a specific implementation manner of the embodiment of the application, the feedforward signal calculation module comprises a change rate calculation unit and a SEL analog quantity selection unit;
the change rate calculation unit is used for calculating an ammonia demand change rate generated by the change of the inlet NOx concentration;
the SEL analog quantity selection unit is used for selecting a change magnification in a manual state or a change magnification in an automatic state.
According to a specific implementation manner of the embodiment of the present application, the calculation formula of the change magnification is:
Q ammonia demand =A×B×N
Wherein M is the change multiplying power, Q t ammonia demand For the ammonia demand at the current scanning moment, Q Ammonia demand The theoretical ammonia demand at any moment, A is the NOx mass concentration at the denitration inlet, B is the flue gas flow,n is a constant.
According to a specific implementation of an embodiment of the present application, n=c×d×e×k1×.×kn, where C is the flue gas density, D is the ammonia nitrogen molar ratio, and E, K1...kn is a coefficient.
According to a specific implementation of an embodiment of the present application, the coefficients include ammonia content coefficients and/or conversion coefficients and/or error coefficients.
According to a specific implementation manner of the embodiment of the present application, when the SEL analog selection unit selects the change magnification in the manual state, the output value of the SEL analog selection unit is the ammonia requirement Q at the current scanning time of the anti-tracking t ammonia demand I.e. Q The SEL module outputs ammonia demand =Q t ammonia demand The change multiplying power M=1, the output value of the feedforward signal computing module is 1, and the output value of the auxiliary regulator is the output value of the main regulator.
According to a specific implementation manner of the embodiment of the present application, when the SEL analog selection unit selects the change magnification in the automatic state, the output value of the SEL analog selection unit is the ammonia demand Q at the automatic input scanning time M/A Ammonia demand I.e.
Compared with the prior art, the application has the following characteristics and beneficial effects:
according to the denitration ammonia supply automatic regulating system with the accurate feedforward signal, when the load of the coal-fired unit and the NOx concentration of the denitration inlet change, the change multiplying power of the theoretical calculation value (ammonia demand) of the ammonia supply flow before and after the change is utilized as the feedforward signal, the change of the NOx concentration of the outlet is advanced, the ammonia supply flow given value (ammonia demand) is accurately and quickly corrected in advance, the ammonia supply automatic regulating system is enabled to have the feedforward function of unit load change, the stable investment is kept without intervention of operators under the working condition of unit load fluctuation, the accurate control of the ammonia supply quantity parameter is realized, and the stable standard emission of the NOx concentration of the denitration outlet is ensured.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a flow chart of a denitration ammonia supply automatic regulating system with accurate feedforward signals according to an embodiment of the present application.
In the figure, 1, a main regulator; 2. a secondary regulator; 3. a feedforward signal calculation module; 4. an ammonia supply amount regulating valve.
Detailed Description
Embodiments of the present application are described in detail below with reference to the accompanying drawings.
It should be understood that the described embodiments are merely some, but not all, of the embodiments of the present application. All other embodiments, based on the embodiments herein, which would be apparent to one of ordinary skill in the art without making any inventive effort, are intended to be within the scope of the present application.
As shown in fig. 1, the embodiment of the application provides a denitration ammonia supply automatic adjusting system with an accurate feedforward signal, which belongs to a cascade control system, and specifically may include a main regulator 1, an auxiliary regulator 2 connected with the main regulator 1, a feedforward signal calculation module 3 connected with the auxiliary regulator 2, and an ammonia supply amount adjusting valve 4 connected with an output end of the auxiliary regulator 2.
Wherein the main regulator 1 is used for detecting the concentration of outlet NOx. The secondary regulator 2 is used for detecting the actual ammonia supply flow rate, and the output value of the secondary regulator 2 is sent to the ammonia supply amount regulating valve 4. The output value of the secondary regulator 2 is the product of the output value of the primary regulator 1 and the output value of the feedforward signal calculation module 3.
In the prior art, the cascade PID control ammonia injection amount calculated by the ammonia nitrogen molar ratio can automatically and well run when the load of the coal-fired unit is stable and the fluctuation of a small range is running, but when the unit changes working conditions, the ammonia supply adjustment is not sensitive, and the deviation generated by oscillation cannot be eliminated.
Compared with the prior art, the feedforward signal calculation module 3 is added, and the product of the output value of the main regulator 1 and the output value of the feedforward signal calculation module 3 is used as the output value of the auxiliary regulator 2, so that the deviation caused by load fluctuation in the prior art can be effectively eliminated, the calculated correction amount is superimposed on the basis of the theoretical ammonia supply amount, and the NOx concentration at the outlet can be effectively regulated within the controllable range under the working condition of load fluctuation of the automatic denitration ammonia supply regulation system.
In one implementation of the present embodiment, the feedforward signal calculating module 3 may include a change magnification calculating unit and a SEL analog quantity selecting unit;
the change rate calculation unit is used for calculating the ammonia demand change rate generated by the change of the flue gas flow or the inlet NOx concentration, and the SEL analog quantity selection unit is used for selecting the change rate in a manual state or the change rate in an automatic state.
Specifically, the calculation formula of the change multiplying power is as follows:
Q ammonia demand =A×B×N
Wherein M is the change multiplying power, Q t ammonia demand For the ammonia demand at the current scanning moment, Q Ammonia demand The theoretical ammonia demand at any moment is represented by A, NOx mass concentration at a denitration inlet, B, flue gas flow and N, wherein N is a constant.
Here, n=c×d×e×k1×.×kn, where C is the smoke density, D is the ammonia nitrogen molar ratio, and E, K1...kn is a coefficient.
The coefficients include ammonia content coefficients and/or conversion coefficients and/or error coefficients. Specifically, C is the density of the flue gas, D is the molar ratio of ammonia nitrogen, E is the ammonia content coefficient, K1..
In one implementation of the present embodiment, when the SEL analog quantity selecting unit selects the change magnification in the manual state, the output value of the SEL analog quantity selecting unit is the ammonia demand Q at the current scanning time of the anti-tracking t ammonia demand I.e. Q The SEL module outputs ammonia demand =Q t ammonia demand The change multiplying power M=1, the output value of the feedforward signal computing module is 1, and the output value of the auxiliary regulator is the output value of the main regulator.
That is, in the manual state, the actual ammonia supply amount is the theoretical ammonia demand amount, and the actual ammonia demand amount in the mode is not corrected and compensated at all, so that the actual ammonia supply amount is not changed from the normal state under the working condition that the load of the unit fluctuates, and therefore, the ammonia supply adjusting effect is not good, and a certain deviation is generated.
In order to solve the above-described problems, in one implementation of the present embodiment, when the SEL analog quantity selection unit selects the change magnification in the automatic state, the output value of the SEL analog quantity selection unit is the ammonia demand Q at the automatic input scanning time M/A Ammonia demand It can also be said that the theoretical ammonia demand, i.e. Q The SEL module outputs ammonia demand =Q M/A Ammonia demand At this time, the variable multiplying power calculation denominator is locked to a constant Q which is fixed M/A Ammonia demand The molecule is real-time ammonia demand Q t ammonia demand C, D, E in the calculation formula is constant, and conversion coefficients such as K1...Kn and error coefficients are considered to be invariable and equal in any period of time when the unit load changes, so that the change multiplying power is madeWhen calculating, C, D, E, K1.. Kn, which are different time periods in the numerator and denominator, can be reduced, i.e. +.>The final variables are only A and B, namely the NOx mass concentration and the flue gas flow of the denitration inlet, and once the NOx mass concentration and the flue gas flow of the denitration inlet are changed, the change multiplying power M is changed1 starts to change. The real-time calculated change multiplying power, namely the output value of the feedforward signal calculating module, is multiplied by the output value of the main regulator to be used as a set value of the auxiliary regulator and is sent to the ammonia supply quantity regulating valve to be used as the ammonia supply quantity in the next time period.
According to the denitration ammonia supply automatic regulating system with the accurate feedforward signal, disclosed by the embodiment, the change multiplying power of the theoretical calculation value of the denitration ammonia supply flow (namely, the ammonia demand) before and after the load change of the coal-fired unit is utilized as the feedforward signal, when the load of the unit changes, the system can be advanced to the change of the concentration of NOx at an outlet through the change multiplying power of the ammonia demand before and after the load change of the unit, the given value of the ammonia supply flow can be accurately and efficiently corrected in advance, the ammonia injection automatic regulation has the accurate feedforward function aiming at the load change of the unit, and the concentration value of NOx at the outlet can still be stably controlled within the expected range along with the load change of the unit, so that the occurrence of the condition that the concentration of NOx is discharged out of standard is avoided. The denitration ammonia supply automatic regulating effect when the load of the coal-fired unit is changed is improved, the full-working-condition ammonia supply automatic operation is realized, and the participation degree of operators is reduced.
It should be noted that, in this document, emphasis on the solutions described between the embodiments is different, but there is a certain interrelation between the embodiments, and when the solution of the present application is understood, the embodiments may be referred to each other; additionally, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.
The foregoing is merely specific embodiments of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions easily conceivable by those skilled in the art within the technical scope of the present application should be covered in the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.
Claims (4)
1. Denitration ammonia supply automatic regulating system of accurate feedforward signal in area, its characterized in that: the device comprises a main regulator (1), an auxiliary regulator (2) connected with the main regulator (1), a feedforward signal calculation module (3) connected with the auxiliary regulator (2) and an ammonia supply amount regulating valve (4) connected with the output end of the auxiliary regulator (2);
the feedforward signal calculation module (3) comprises a change multiplying power calculation unit and a SEL analog quantity selection unit;
the change rate calculation unit is used for calculating an ammonia demand change rate generated by the change of the inlet NOx concentration;
the SEL analog quantity selection unit is used for selecting a change multiplying power in a manual state or a change multiplying power in an automatic state;
the calculation formula of the change multiplying power is as follows:
Q ammonia demand =A×B×N
Wherein M is the change multiplying power, Q t ammonia demand For the ammonia demand at the current scanning moment, Q Ammonia demand The ammonia is theoretical ammonia demand at any moment, A is NOx mass concentration at a denitration inlet, B is flue gas flow, and N is a constant;
n=c×d×e×k1×.×kn, where C is the flue gas density, D is the ammonia nitrogen molar ratio, E, K1...kn is the coefficient;
the coefficients include ammonia content coefficients and/or conversion coefficients and/or error coefficients;
when the SEL analog quantity selection unit selects the change multiplying power in the manual state, the output value of the SEL analog quantity selection unit is the ammonia demand Q of the current scanning moment of the anti-tracking t ammonia demand I.e. Q The SEL module outputs ammonia demand =Q t ammonia demand The change multiplying power M=1, the output value of the feedforward signal calculation module is 1, and the output value of the auxiliary regulator is the output value of the main regulator;
2. The automatic denitration ammonia supply adjusting system with accurate feedforward signals according to claim 1, wherein: the main regulator (1) is used for detecting the concentration of the outlet NOx.
3. The automatic denitration ammonia supply adjusting system with accurate feedforward signals according to claim 1, wherein: the auxiliary regulator (2) is used for detecting the actual ammonia supply flow, and the output value of the auxiliary regulator (2) is sent to the ammonia supply quantity regulating valve (4).
4. The automatic denitration ammonia supply adjusting system with accurate feedforward signals according to claim 1, wherein: the output value of the secondary regulator (2) is the product of the output value of the primary regulator (1) and the output value of the feedforward signal calculation module (3).
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202210262324.7A CN114632417B (en) | 2022-03-17 | 2022-03-17 | Denitration ammonia supply automatic regulating system with accurate feedforward signal |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202210262324.7A CN114632417B (en) | 2022-03-17 | 2022-03-17 | Denitration ammonia supply automatic regulating system with accurate feedforward signal |
Publications (2)
Publication Number | Publication Date |
---|---|
CN114632417A CN114632417A (en) | 2022-06-17 |
CN114632417B true CN114632417B (en) | 2023-04-25 |
Family
ID=81949304
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202210262324.7A Active CN114632417B (en) | 2022-03-17 | 2022-03-17 | Denitration ammonia supply automatic regulating system with accurate feedforward signal |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN114632417B (en) |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN107561941A (en) * | 2017-09-01 | 2018-01-09 | 华北电力大学(保定) | A kind of full working scope qualified discharge control method of fired power generating unit denitrating system |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3565607B2 (en) * | 1995-03-03 | 2004-09-15 | バブコック日立株式会社 | Method and apparatus for controlling amount of ammonia injection into denitration device |
CN108628177A (en) * | 2018-07-02 | 2018-10-09 | 大唐环境产业集团股份有限公司 | A kind of SCR denitration intelligence spray ammonia optimization method and system based on model adaptation PID |
CN109453664B (en) * | 2018-12-25 | 2023-06-02 | 国电科学技术研究院有限公司 | Ammonia injection control method and denitration system for coal-fired power plant based on big data analysis |
CN110501901B (en) * | 2019-07-08 | 2022-05-10 | 华能南京金陵发电有限公司 | SCR ammonia injection regulation optimization method based on full-load accurate denitration requirement |
CN112915741A (en) * | 2021-01-13 | 2021-06-08 | 中国大唐集团科学技术研究院有限公司火力发电技术研究院 | Denitration optimization method |
-
2022
- 2022-03-17 CN CN202210262324.7A patent/CN114632417B/en active Active
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN107561941A (en) * | 2017-09-01 | 2018-01-09 | 华北电力大学(保定) | A kind of full working scope qualified discharge control method of fired power generating unit denitrating system |
Also Published As
Publication number | Publication date |
---|---|
CN114632417A (en) | 2022-06-17 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN107561941B (en) | Full-working-condition standard-reaching emission control method for thermal power generating unit denitration system | |
CN105797576B (en) | Denitration ammonia injection control method for coal-fired unit | |
CN104607042B (en) | A kind of SCR denitration system and method based on constrained forecast control | |
JPH0342930B2 (en) | ||
CN110501901B (en) | SCR ammonia injection regulation optimization method based on full-load accurate denitration requirement | |
CN105700570B (en) | SCR denitration control method for thermal power plant | |
US9631776B2 (en) | Model-based controls for selective catalyst reduction systems | |
CN104793652B (en) | A kind of ammonia spraying amount adjusting method and system based on load scheduling curve | |
CN114632417B (en) | Denitration ammonia supply automatic regulating system with accurate feedforward signal | |
CN114307627B (en) | Denitration adjusting method based on theoretical ammonia consumption | |
US20030145601A1 (en) | Feed back control method in V-shaped characteristic system, and NH3 injection rate control method for NOx removal apparatus using the same | |
US8527071B2 (en) | Adaptive control system for a sulfur recovery process | |
CN109603453A (en) | The control method of lime stone inventory in circulating fluidized bed boiler | |
JP3500208B2 (en) | DeNOx control device | |
JP4668852B2 (en) | Denitration equipment for combustion equipment | |
JPH0633743A (en) | Denitration control device | |
CN113325693A (en) | Improved PID control method and device for SCR denitration system | |
WO2006045081A2 (en) | Predictive header pressure control | |
JP2635643B2 (en) | Denitration control device for gas turbine plant | |
US6237368B1 (en) | Process for the regulating or controlling the NOx content of exhaust gases given off during the operating of glass melting furnaces with several burners run alternately | |
JPH0428971B2 (en) | ||
JPH0754611A (en) | Denitration control device | |
CN117167756A (en) | Externally hung boiler denitration ammonia injection control system and control method | |
JP2001104755A (en) | Method and apparatus for controlling ammonia injection amount to denitration apparatus | |
JPS60216829A (en) | Denitration apparatus |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
GR01 | Patent grant | ||
GR01 | Patent grant | ||
TR01 | Transfer of patent right | ||
TR01 | Transfer of patent right |
Effective date of registration: 20231201 Address after: 100039 room 901, 9 / F, building 1, yard 16, West Fourth Ring Middle Road, Haidian District, Beijing Patentee after: Guoneng Longyuan environmental protection Co.,Ltd. Patentee after: Guoneng (Shandong) energy environment Co.,Ltd. Address before: 100039 room 901, 9 / F, building 1, yard 16, West Fourth Ring Middle Road, Haidian District, Beijing Patentee before: Guoneng Longyuan environmental protection Co.,Ltd. |