CN107286058B - Urea first-stage evaporation control system and method - Google Patents
Urea first-stage evaporation control system and method Download PDFInfo
- Publication number
- CN107286058B CN107286058B CN201710724273.4A CN201710724273A CN107286058B CN 107286058 B CN107286058 B CN 107286058B CN 201710724273 A CN201710724273 A CN 201710724273A CN 107286058 B CN107286058 B CN 107286058B
- Authority
- CN
- China
- Prior art keywords
- section
- evaporation
- outlet
- evaporator
- stage
- 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
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C273/00—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups
- C07C273/02—Preparation of urea or its derivatives, i.e. compounds containing any of the groups, the nitrogen atoms not being part of nitro or nitroso groups of urea, its salts, complexes or addition compounds
- C07C273/14—Separation; Purification; Stabilisation; Use of additives
- C07C273/16—Separation; Purification
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P90/00—Enabling technologies with a potential contribution to greenhouse gas [GHG] emissions mitigation
- Y02P90/02—Total factory control, e.g. smart factories, flexible manufacturing systems [FMS] or integrated manufacturing systems [IMS]
Abstract
The invention discloses a urea first-stage evaporation concentration control system, which comprises a first-stage evaporation separator, a first-stage evaporation heater connected with the first-stage evaporation separator, a main pipeline, a first-stage evaporation urine concentration controller, a first-stage evaporation outlet thermocouple thermometer, a first-stage evaporation heater steam pressure regulating valve, a first-stage evaporation outlet temperature cascade regulator, a first-stage evaporation heater steam pressure transmitter, a first-stage evaporator vacuum degree transmitter, a first-stage evaporator concentration cascade regulator, a first-stage evaporator vacuum degree pressure regulating valve and a control system. The invention provides a novel method and a novel system for indirectly calculating the concentration of evaporated urine. CO of the invention and the contemporaneous construction 2 Compared with a steam stripping device, the investment can be saved by more than 30 percent, and the steam consumption is reduced to 905 kg/ton. The invention has high safety, more stability and reliability; convenient operation, simple control and high automation degree. The invention also discloses a urea first-stage evaporation concentration control method.
Description
Technical Field
The invention relates to the field of urea manufacturing, in particular to a urea first-stage evaporation control system and method.
Background
The concentration of urine at the outlet of the first-stage evaporation of urea is not easy to analyze on line due to the characteristics of high temperature, easy crystallization and the like. The analyzer manufacturers all over the world study the urea concentration as a subject, and usually adopt manual analysis to calculate the concentration of urine by the principle that pressure/temperature and the concentration of urine form a mathematical model relation so as to control the concentration of urine at a first-stage evaporation outlet of urea.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a urea first-stage evaporation control system and method capable of carrying out online analysis to indirectly calculate the concentration of first-stage evaporation urine.
The purpose of the invention is realized by the following technical scheme: the urea first-stage evaporation concentration control system comprises a first-stage evaporation separator, a first-stage evaporation heater connected with the first-stage evaporation separator, a main pipeline, a first-stage evaporation urine concentration controller, a first-stage evaporation outlet thermocouple thermometer, a first-stage evaporation heater steam pressure regulating valve, a first-stage evaporation outlet temperature cascade regulator, a first-stage evaporation heater steam pressure transmitter, a first-stage evaporator vacuum degree transmitter, a first-stage evaporator concentration cascade regulator, a first-stage evaporator vacuum degree pressure regulating valve and a control system;
the first section of evaporated urine concentration controller is arranged beside the first section of on-site evaporated separator and is convenient to watch and operate, or the first section of evaporated urine concentration controller is a functional module in the control system; monitoring temperature and pressure, calculating and outputting a signal to a control system;
the control system is a DCS control system;
the main pipelines comprise a section of evaporator separator outlet main pipeline, a section of evaporator separator vacuumizing main pipeline, a section of evaporation heater steam inlet main pipeline and a liquid pump main pipeline; the section of evaporation heater steam inlet main pipeline and the section of liquid pump main pipeline are respectively communicated with the section of evaporation heater, and the section of evaporator separator outlet main pipeline and the section of evaporator separator vacuumizing main pipeline are respectively communicated with the section of evaporation separator;
a section of evaporation heater steam pressure regulating valve is arranged on the section of evaporation heater steam inlet main pipeline;
the first section of evaporation heater steam pressure transmitter is arranged on the first section of evaporation heater steam inlet main pipeline or the first section of evaporation heater;
a section of evaporation outlet thermocouple thermometer is arranged on the section of evaporator separator outlet main pipeline;
a vacuum degree pressure regulating valve of the evaporator is arranged on the vacuum pumping main pipeline of the evaporator separator;
the first-stage evaporation separator is provided with a first-stage evaporator vacuum transmitter;
the first section evaporation heater steam pressure regulating valve, the first section evaporation heater steam pressure transmitter and the first section evaporation outlet thermocouple thermometer are respectively and electrically connected with the first section evaporation outlet temperature cascade regulator;
the first-section evaporator concentration cascade regulator is respectively connected with a first-section evaporator vacuum pressure regulating valve, a first-section evaporator vacuum transmitter and a first-section evaporated urine concentration controller; the first section of evaporated urine concentration controller is also respectively connected with a first section of evaporator vacuum degree transmitter and a first section of evaporation outlet thermocouple thermometer.
As a preferred mode, one section evaporation outlet urine concentration controller install one section evaporation separator side, one section evaporation urine concentration controller on be provided with the display screen, the display screen is used for showing parameters such as temperature, pressure.
As a preferred mode, a temperature protecting sleeve with phi 14 and the length of 300mm is arranged on an opening of a section of main pipeline at the outlet of the evaporation separator, and the length of a section of thermocouple thermometer at the evaporation outlet is consistent with that of the temperature measuring protecting sleeve; the first-stage evaporation outlet thermocouple thermometer adopts three I-grade E-scale thermocouple thermometers, and temperature signals are connected to the first-stage evaporation urine concentration controller.
As a preferable mode, the first section of evaporation heater steam pressure transmitter is arranged on the first section of evaporation heater, a stop valve is arranged on an opening at the upper part of the first section of evaporation heater, a phi 14 stainless steel pressure guiding pipe is used for introducing the positive pressure side of the first section of evaporation heater steam pressure transmitter, and a transmitter signal is transmitted to a DCS control system.
As a preferred mode, the first section of evaporator vacuum transmitter is arranged at the top of the first section of evaporator separator, a stop valve is arranged on an opening at the top of the first section of evaporator separator, a phi 14 stainless steel pressure leading pipe is used for leading the pressure signal to the positive pressure side of the first section of evaporator vacuum transmitter, the pressure signal is connected to the first section of evaporated urine concentration controller, an absolute pressure meter is used for detecting negative pressure, and the transmitter signal is sent to the first section of evaporated urine concentration controller.
A urea first-stage evaporation control method comprises the steps of sending a vacuum pressure signal detected by a first-stage evaporation separator urine outlet temperature and a first-stage evaporator vacuum degree transmitter to a first-stage evaporation urine concentration controller, wherein a first-stage evaporation outlet urine concentration calculation module is arranged in the first-stage evaporation urine concentration controller, the first-stage evaporation outlet urine concentration calculation module calculates a urine concentration value according to the temperature signal and the pressure signal, the calculated concentration value is sent to a DCS control system, the DCS control system outputs a given signal serving as a first-stage evaporator concentration cascade regulator, the signal of the first-stage evaporation outlet vacuum degree transmitter is measured and sent to a measuring end of the first-stage evaporator concentration cascade regulator, a urine concentration cascade loop is formed, and the opening degree of the first-stage evaporator vacuum degree pressure regulating valve is controlled.
Preferably, the DCS control system manually operates the first-stage evaporation outlet temperature cascade regulator,
when the steam pressure is stable, the cascade regulator of the temperature of the first-stage evaporation outlet is put into 'automatic', and the single regulator is formed at the moment;
when the pressure of the steam pressure transmitter of the first section of the evaporation heater rises, the steam pressure transmitter of the first section of the evaporation heater is adjusted by the temperature cascade regulator of the first section of the evaporation outlet, and the steam pressure regulating valve of the first section of the evaporation heater is closed;
when the pressure of the steam pressure transmitter of the first-section evaporation heater is reduced, the steam pressure regulating valve of the first-section evaporation heater is opened greatly through the regulation of the temperature cascade regulator of the evaporation outlet of the first-section evaporation heater;
when cascade connection is carried out, the temperature of a first-section evaporation outlet rises, and is regulated by a first-section evaporation temperature cascade regulator, and a first-section evaporation heater steam pressure regulating valve is closed; the temperature of the first-section evaporation outlet is reduced, and the steam pressure regulating valve of the first-section evaporation heater is opened greatly through the regulation of the first-section evaporation temperature cascade regulator.
As a preferred mode, the first-section evaporation outlet urine concentration controller is arranged on the side surface of the first-section evaporation separator, and the first-section evaporation outlet urine concentration controller, the first-section evaporator vacuum degree transmitter and the first-section evaporator vacuum degree pressure regulating valve form a concentration cascade regulating loop;
the temperature of the urine outlet of the first-stage evaporation separator and the vacuum degree signal of the first-stage evaporation separator are sent to a first-stage evaporation urine concentration controller, a concentration value is calculated in the first-stage evaporation urine concentration controller through a first-stage evaporation outlet urine concentration calculation module, and a concentration value signal calculated by the first-stage evaporation outlet urine concentration calculation module is sent to a DCS (distributed control System);
when the vacuum pressure of the first-stage evaporation outlet rises, the vacuum degree pressure regulating valve of the first-stage evaporator is closed to control the vacuum degree to be 35KPa (A) through the regulation of a first-stage evaporator concentration cascade regulator;
at the moment, the temperature of the first-section evaporation outlet is reduced, and the steam pressure regulating valve of the first-section evaporation heater is opened greatly through the regulation of the first-section evaporation outlet temperature cascade regulator; controlling the temperature of a first-stage evaporation outlet at 130 ℃;
manually operating a section of evaporator concentration cascade regulator on a DCS (distributed control system), and after a section of evaporation outlet vacuum pressure transmitter is stabilized, switching the section of evaporator concentration cascade regulator to be automatic, and switching a section of evaporation urine concentration controller to be cascade to form a complex cascade loop; at the moment, the complex cascade loop works formally;
when the concentration calculated by the first-section evaporation outlet urine concentration calculation module is less than 95%, the concentration is adjusted by the first-section evaporation urine concentration controller, and the vacuum pressure adjusting valve of the first-section evaporator acts along with the first-section evaporation outlet urine concentration calculation module to open the adjusting valve greatly;
the temperature of the evaporation outlet of the first section is reduced, and the steam pressure regulating valve of the evaporation heater of the first section is opened greatly through the regulation of the temperature cascade regulator of the evaporation outlet of the first section.
The invention has the beneficial effects that: the invention provides a novel method for indirectly calculating the concentration of one-section evaporated urineAnd a system. CO of the invention and the contemporaneous construction 2 Compared with a steam stripping device, the investment can be saved by more than 30 percent, and the steam consumption is reduced to 905 kg/ton. The invention has high safety, and is more stable and reliable; convenient operation, simple control and high automation degree.
Drawings
FIG. 1 is a schematic diagram of the system of the present invention;
in the figure, 1-a section of evaporator vacuum degree pressure regulating valve, 2-a section of evaporator concentration cascade regulator, 3-a section of evaporation urine concentration controller, 4-a section of evaporator vacuum degree transmitter, 5-a section of evaporation outlet temperature cascade regulator, 6-a section of evaporation outlet thermocouple thermometer, 7-a section of evaporation heater steam pressure transmitter, 8-a section of evaporation heater steam pressure regulating valve, 9-a section of evaporation heater and 10-a section of evaporation separator.
Detailed Description
The technical solutions of the present invention are further described in detail below with reference to the accompanying drawings, but the scope of the present invention is not limited to the following.
As shown in fig. 1, a represents a section of a main vacuum pumping line of an evaporator separator, B represents a section of a main steam inlet line of an evaporation heater, C represents a section of a main outlet line of an evaporator separator, and D represents a main liquid pump line.
The urea first-stage evaporation concentration control system comprises a first-stage evaporation separator 10, a first-stage evaporation heater 9 connected with the first-stage evaporation separator 10, a main pipeline, a first-stage evaporation urine concentration controller 3, a first-stage evaporation outlet thermocouple thermometer 6, a first-stage evaporation heater steam pressure regulating valve 8, a first-stage evaporation outlet temperature cascade regulator 5, a first-stage evaporation heater steam pressure transmitter 7, a first-stage evaporator vacuum degree transmitter 4, a first-stage evaporator concentration cascade regulator 2, a first-stage evaporator vacuum degree pressure regulating valve 1 and a control system;
the section of evaporated urine concentration controller 3 is arranged beside the section of on-site evaporated separator 10 so as to be convenient to watch and operate, or the section of evaporated urine concentration controller 3 is a functional module in a control system; monitoring temperature and pressure, calculating and outputting a signal to a control system;
the control system is a DCS control system;
the main pipelines comprise a section of evaporator separator outlet main pipeline, a section of evaporator separator vacuumizing main pipeline, a section of evaporation heater 9 steam inlet main pipeline and a liquid pump main pipeline; a section of evaporation heater 9 steam inlet main pipeline and a section of liquid pump main pipeline are respectively communicated with a section of evaporation heater 9, and a section of evaporator separator outlet main pipeline and a section of evaporator separator vacuumizing main pipeline are respectively communicated with a section of evaporation separator 10;
a steam inlet main pipeline of the first section of the evaporation heater 9 is provided with a steam pressure regulating valve 8 of the first section of the evaporation heater;
the first section of evaporation heater steam pressure transmitter 7 is arranged on a main steam inlet pipeline of the first section of evaporation heater 9 or the first section of evaporation heater 9;
a section of evaporation outlet thermocouple thermometer 6 is arranged on the section of evaporator separator outlet main pipeline;
a vacuum degree pressure regulating valve 1 of the first section of evaporator is arranged on a vacuumizing main pipeline of the first section of evaporator separator;
the first-stage evaporation separator 10 is provided with a first-stage evaporator vacuum transmitter 4;
the first-section evaporation heater steam pressure regulating valve 7, the first-section evaporation heater steam pressure transmitter 7 and the first-section evaporation outlet thermocouple thermometer 6 are respectively and electrically connected with the first-section evaporation outlet temperature cascade regulator 5;
the first-stage evaporator concentration cascade regulator 2 is respectively connected with a first-stage evaporator vacuum pressure regulating valve 1, a first-stage evaporator vacuum transmitter 4 and a first-stage evaporated urine concentration controller 3; the first section of evaporated urine concentration controller 3 is also respectively connected with a first section of evaporator vacuum transmitter 4 and a first section of evaporation outlet thermocouple thermometer 6.
Preferably, one section evaporation outlet urine concentration controller installs in one section evaporation separator 10 side, one section evaporation urine concentration controller 3 on be provided with the display screen, the display screen is used for showing temperature, pressure etc..
Preferably, a temperature protecting sleeve with the phi 14 length of 300mm is arranged on an opening of a main pipeline at the outlet of the first section of the evaporation separator 10, and the length of the first section of the evaporation outlet thermocouple thermometer 6 is consistent with that of the temperature measuring protecting sleeve; the first section evaporation outlet thermocouple thermometer 6 adopts a group of three I-grade E-scale thermocouple thermometers, and temperature signals are connected to the first section evaporation urine concentration controller 3.
Preferably, the first section of evaporation heater steam pressure transmitter 7 is arranged on the first section of evaporation heater 9, a stop valve is installed on an opening at the upper part of the first section of evaporation heater 9, a phi 14 stainless steel pressure guiding pipe is used for introducing the positive pressure side of the first section of evaporation heater steam pressure transmitter 7, and a transmitter signal is transmitted to the DCS control system.
Preferably, the first-stage evaporator vacuum degree transmitter 4 is arranged at the top of the first-stage evaporator separator 10, a stop valve is installed at an opening at the top of the first-stage evaporator separator 10, a phi 14 stainless steel pressure leading pipe is used for leading the positive pressure side of the first-stage evaporator vacuum degree transmitter 4, an absolute pressure gauge is used for detecting negative pressure, and a transmitter signal is sent to the first-stage evaporation urine concentration controller 3.
A urea first-stage evaporation control method comprises the steps of sending a vacuum pressure signal detected by a first-stage evaporation separator 10 urine outlet temperature and a first-stage evaporator vacuum degree transmitter 4 into a first-stage evaporation urine concentration controller 3, arranging a first-stage evaporation outlet urine concentration calculation module in the first-stage evaporation urine concentration controller 3, calculating a urine concentration value by the first-stage evaporation outlet urine concentration calculation module according to the temperature and the pressure signal, sending the calculated concentration value to a DCS control system, outputting a given signal serving as a first-stage evaporator concentration cascade regulator 2 by the DCS control system, measuring a first-stage evaporation outlet vacuum degree transmitter signal, sending the measured signal to a measuring end of the first-stage evaporator concentration cascade regulator 2 to form a urine concentration cascade loop, and controlling the opening degree of the first-stage evaporator vacuum degree pressure regulating valve 1.
Preferably, the first stage evaporation outlet temperature cascade regulator 5 is manually operated in the DCS control system,
when the steam pressure is stable, the first-section evaporation outlet temperature cascade regulator 5 is turned into 'automatic', and the single regulator is formed at the moment;
when the pressure of the first-section evaporation heater steam pressure transmitter 7 rises, the first-section evaporation heater steam pressure regulating valve 8 is closed through the regulation of the first-section evaporation outlet temperature cascade regulator 5;
when the pressure of the first-section evaporation heater steam pressure transmitter 7 is reduced, the first-section evaporation heater steam pressure regulating valve 8 is opened to be larger through the regulation of the first-section evaporation outlet temperature cascade regulator 5;
when cascade connection is carried out, the temperature of a first-section evaporation outlet rises, and is regulated by a first-section evaporation temperature cascade regulator, and a first-section evaporation heater steam pressure regulating valve 8 is turned down; the temperature of the first-section evaporation outlet is reduced, and the steam pressure regulating valve 8 of the first-section evaporation heater is opened to be larger through the regulation of the first-section evaporation temperature cascade regulator.
Preferably, the first-section evaporation outlet urine concentration controller is installed on the side surface of the first-section evaporation separator 10, and the first-section evaporation outlet urine concentration controller, the first-section evaporator vacuum degree transmitter 4 and the first-section evaporator vacuum degree pressure regulating valve 1 form a concentration cascade regulating loop;
signals of the temperature of the urine outlet of the first-stage evaporation separator 10 and the vacuum degree of the first-stage evaporation separator 10 are sent to a first-stage evaporation urine concentration controller 3, concentration values are calculated in the first-stage evaporation urine concentration controller 3 through a first-stage evaporation outlet urine concentration calculating module, and concentration value signals calculated by the first-stage evaporation outlet urine concentration calculating module are sent to a DCS (distributed control System);
when the vacuum pressure of the first-stage evaporation outlet rises, the vacuum degree pressure regulating valve 1 of the first-stage evaporator is closed to control the vacuum degree to be 35KPa (A) through the regulation of the first-stage evaporator concentration cascade regulator 2;
at the moment, the temperature of the first-stage evaporation outlet is reduced, and the steam pressure regulating valve 8 of the first-stage evaporation heater is opened to be large through the regulation of the first-stage evaporation outlet temperature cascade regulator 5; controlling the temperature of a first-stage evaporation outlet at 130 ℃;
manually operating a section of evaporator concentration cascade regulator 2 on a DCS operating system, and after a section of evaporation outlet vacuum pressure transmitter is stabilized, switching the section of evaporator concentration cascade regulator 2 to be 'automatic', and switching the section of evaporation urine concentration controller 3 to be 'cascade', so as to form a complex cascade loop; at the moment, the complex cascade loop works formally;
when the concentration calculated by the first-stage evaporation outlet urine concentration calculation module is less than 95%, the first-stage evaporation outlet urine concentration is adjusted by the first-stage evaporation urine concentration controller 3, and the first-stage evaporator vacuum degree pressure adjusting valve 1 acts along with the first-stage evaporation outlet urine concentration calculation module to open the adjusting valve greatly;
the temperature of the first-section evaporation outlet is reduced and is regulated by the first-section evaporation outlet temperature cascade regulator 5, and the steam pressure regulating valve 8 of the first-section evaporation heater is opened.
The input end of the first-section evaporator concentration cascade regulator 2 is used as a given signal of a first-section evaporation vacuum degree pressure regulating valve, and the first-section evaporation urine concentration controller 3 outputs and controls the first-section evaporation vacuum degree pressure regulating valve to regulate the urine concentration of a first-section evaporation outlet; the principle of the invention is as follows: the urine pressure/temperature and the urine concentration are in a mathematical model relation to calculate the concentration of the urine. The mathematical model is as follows:
A＝16.2886-3816.44/(RV1+227.02)
B＝EXP(A)
C＝0.94×RV/B
D＝POWER(C,0.92498)
E＝1.06425×D
F＝100×(18.016×E)/{(18.016×E)+60.056×(1-E)}
F1＝POWER(F,2)
G＝132.6-2.7085×F+0.0058×F1
note: RV1 as temperature input signal
RV: for inputting signals to pressure
G is concentration
Temperature control and pressure control; the temperature control sends a signal for measuring the temperature of the urine outlet of the first section of evaporator to the measuring end of the temperature cascade regulator 5 of the first section of evaporation outlet, and a signal for measuring the steam pressure transmitter 7 of the first section of evaporation heater is sent to the input end of the temperature cascade regulator 5 of the first section of evaporation outlet to form a temperature cascade loop, and the opening of the steam pressure regulating valve 8 of the first section of evaporation heater is controlled; the pressure control sends the temperature of the urine outlet of the first section of evaporator and the signal of the vacuum pressure detector of the first section of evaporation outlet to the concentration controller 3 of the first section of evaporation urine, the concentration value of the first section of evaporation urine is calculated by the concentration calculation module of the urine concentration of the first section of evaporation outlet by the concentration controller 3 of the first section of evaporation urine, and the vacuum pressure signal is sent to the measuring value end of the concentration cascade regulator of the first section of evaporation urine to form a cascade loop, and the opening degree of the vacuum pressure regulating valve of the first section of evaporation heater 9 is controlled.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, it should be noted that any modifications, equivalents and improvements made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (7)
1. The urea one-section evaporation concentration control device is characterized in that: the system comprises a section of evaporation separator, a section of evaporation heater connected with the section of evaporation separator, a main pipeline, a section of evaporated urine concentration controller, a section of evaporation outlet thermocouple thermometer, a section of evaporation heater steam pressure regulating valve, a section of evaporation outlet temperature cascade regulator, a section of evaporation heater steam pressure transmitter, a section of evaporator vacuum degree transmitter, a section of evaporator concentration cascade regulator, a section of evaporator vacuum degree pressure regulating valve and a control system;
the first section of evaporated urine concentration controller is arranged beside the first section of on-site evaporated separator or the first section of evaporated urine concentration controller is a functional module in the control system; monitoring temperature and pressure, calculating and outputting a signal to a control system;
the control system is a DCS control system;
the main pipelines comprise a section of evaporator separator outlet main pipeline, a section of evaporator separator vacuumizing main pipeline, a section of evaporation heater steam inlet main pipeline and a liquid pump main pipeline; the section of evaporation heater steam inlet main pipeline and the section of liquid pump main pipeline are respectively communicated with the section of evaporation heater, and the section of evaporator separator outlet main pipeline and the section of evaporator separator vacuumizing main pipeline are respectively communicated with the section of evaporation separator;
a section of evaporation heater steam pressure regulating valve is arranged on the section of evaporation heater steam inlet main pipeline;
the first section of evaporation heater steam pressure transmitter is arranged on the first section of evaporation heater steam inlet main pipeline or the first section of evaporation heater;
a section of evaporation outlet thermocouple thermometer is arranged on the section of evaporator separator outlet main pipeline;
a vacuum degree pressure regulating valve of the first evaporator is arranged on a vacuum pumping main pipeline of the first evaporator separator;
the first-stage evaporation separator is provided with a first-stage evaporator vacuum transmitter;
the first section evaporation heater steam pressure regulating valve, the first section evaporation heater steam pressure transmitter and the first section evaporation outlet thermocouple thermometer are respectively and electrically connected with the first section evaporation outlet temperature cascade regulator;
the first-section evaporator concentration cascade regulator is respectively connected with a first-section evaporator vacuum pressure regulating valve, a first-section evaporator vacuum transmitter and a first-section evaporated urine concentration controller; the first section of evaporated urine concentration controller is also respectively connected with a first section of evaporator vacuum degree transmitter and a first section of evaporation outlet thermocouple thermometer;
the control method of the control device comprises the following steps: the method comprises the steps of sending vacuum pressure signals detected by a first-section evaporation separator urine outlet temperature transmitter and a first-section evaporator vacuum degree transmitter into a first-section evaporation urine concentration controller, arranging a first-section evaporation outlet urine concentration calculation module in the first-section evaporation urine concentration controller, calculating a urine concentration value by the first-section evaporation outlet urine concentration calculation module according to temperature and pressure signals, sending the calculated concentration value to a DCS control system, outputting a given signal serving as a first-section evaporator concentration cascade regulator by the DCS control system, measuring a first-section evaporation outlet vacuum degree transmitter signal, sending the measured signal to a measuring end of the first-section evaporator concentration cascade regulator to form a urine concentration cascade loop, and controlling the opening degree of the first-section evaporator vacuum degree pressure regulating valve.
2. The primary urea evaporative concentration control apparatus of claim 1, wherein: one section evaporation outlet urine concentration controller install one section evaporation separator side, one section evaporation urine concentration controller on be provided with the display screen.
3. The primary urea evaporative concentration control apparatus of claim 2, wherein: a temperature protecting sleeve with the phi 14 length of 300mm is arranged on an opening on a section of main pipeline at the outlet of the evaporation separator, and the length of a section of thermocouple thermometer at the evaporation outlet is consistent with that of the temperature measuring protecting sleeve; the first-stage evaporation outlet thermocouple thermometer adopts three I-grade E-scale thermocouple thermometers, and temperature signals are connected to the first-stage evaporation urine concentration controller.
4. The primary urea evaporative concentration control apparatus of claim 3, wherein: the section of evaporation heater steam pressure transmitter is arranged on the section of evaporation heater, a stop valve is arranged on an opening at the upper part of the section of evaporation heater, a phi 14 stainless steel pressure guiding pipe is used for introducing the positive pressure side of the section of evaporation heater steam pressure transmitter, and a transmitter signal is transmitted to the DCS control system.
5. The primary urea evaporative concentration control apparatus of claim 4, wherein: the section of evaporator vacuum transmitter is arranged at the top of the section of evaporator separator, a stop valve is arranged on an opening at the top of the section of evaporator separator, a phi 14 stainless steel pressure leading pipe is used for leading the positive pressure side of the section of evaporator vacuum transmitter, an absolute pressure meter is used for detecting negative pressure, and a transmitter signal is sent to the section of evaporated urine concentration controller.
6. The control method of the control device according to claim 1, characterized in that: a first-stage evaporation outlet temperature cascade regulator is manually operated in a DCS control system,
when the steam pressure is stable, the cascade regulator of the temperature of the first-stage evaporation outlet is put into 'automatic', and the single regulator is formed at the moment;
when the pressure of the steam pressure transmitter of the first-section evaporation heater rises, the steam pressure regulating valve of the first-section evaporation heater is turned off by regulating the temperature cascade regulator of the first-section evaporation outlet;
when the pressure of the steam pressure transmitter of the first-section evaporation heater is reduced, the steam pressure regulating valve of the first-section evaporation heater is opened greatly through the regulation of the temperature cascade regulator of the evaporation outlet of the first section;
when cascade connection is carried out, the temperature of a first-section evaporation outlet rises, and is regulated by a first-section evaporation temperature cascade regulator, and a first-section evaporation heater steam pressure regulating valve is closed; the temperature of the first-section evaporation outlet is reduced, and the steam pressure regulating valve of the first-section evaporation heater is opened greatly through the regulation of the first-section evaporation temperature cascade regulator.
7. The control method of the control device according to claim 1, characterized in that: the first-section evaporation outlet urine concentration controller is arranged on the side surface of the first-section evaporation separator, and the first-section evaporation outlet urine concentration controller, the first-section evaporator vacuum degree transmitter and the first-section evaporator vacuum degree pressure regulating valve form a concentration cascade regulating loop;
the temperature of the urine outlet of the first-stage evaporation separator and the vacuum degree signal of the first-stage evaporation separator are sent to a first-stage evaporation urine concentration controller, a concentration value is calculated in the first-stage evaporation urine concentration controller through a first-stage evaporation outlet urine concentration calculation module, and a concentration value signal calculated by the first-stage evaporation outlet urine concentration calculation module is sent to a DCS (distributed control System);
when the vacuum pressure of the first-stage evaporation outlet rises, the vacuum degree pressure regulating valve of the first-stage evaporator is closed to control the vacuum degree to be 35KPa through the regulation of the concentration cascade regulator of the first-stage evaporator;
at the moment, the temperature of the first-section evaporation outlet is reduced, and the steam pressure regulating valve of the first-section evaporation heater is opened greatly through the regulation of the first-section evaporation outlet temperature cascade regulator; controlling the temperature of a first-stage evaporation outlet at 130 ℃;
manually operating a section of evaporator concentration cascade regulator on a DCS operating system, and after a section of evaporation outlet vacuum pressure transmitter is stabilized, switching the section of evaporator concentration cascade regulator to be automatic, and switching the section of evaporation urine concentration controller to be cascade to form a complex cascade loop; at the moment, the complex cascade loop works formally;
when the concentration calculated by the first-section evaporation outlet urine concentration calculation module is less than 95%, the first-section evaporation outlet urine concentration controller adjusts the concentration, the first-section evaporator vacuum degree pressure regulating valve acts accordingly, and the regulating valve is opened greatly;
the temperature of the evaporation outlet at the first section is reduced, and the steam pressure regulating valve of the evaporation heater at the first section is opened greatly through the regulation of the cascade regulator of the temperature of the evaporation outlet at the first section.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710724273.4A CN107286058B (en) | 2017-08-22 | 2017-08-22 | Urea first-stage evaporation control system and method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710724273.4A CN107286058B (en) | 2017-08-22 | 2017-08-22 | Urea first-stage evaporation control system and method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107286058A CN107286058A (en) | 2017-10-24 |
| CN107286058B true CN107286058B (en) | 2023-04-18 |
Family
ID=60106739
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710724273.4A Active CN107286058B (en) | 2017-08-22 | 2017-08-22 | Urea first-stage evaporation control system and method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107286058B (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112007370A (en) * | 2020-09-23 | 2020-12-01 | 内蒙古通威高纯晶硅有限公司 | Material concentration control system and method |
| CN114681935A (en) * | 2020-12-28 | 2022-07-01 | 攀枝花恒通钛业有限公司 | Automatic control process for concentration of low-concentration titanium liquid |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1749242A (en) * | 2005-08-03 | 2006-03-22 | 四川泸天化股份有限公司 | Method for concentrating thin urine using falling film type evaporation heater |
| CN101239268A (en) * | 2008-03-21 | 2008-08-13 | 李洪林 | Method and device for recovering dust of urea granulation |
| CN201525815U (en) * | 2009-09-30 | 2010-07-14 | 宁波金远东工业科技有限公司 | Device for preparing urea by utilizing aqueous solution total recycle process |
| CN101991962A (en) * | 2009-08-21 | 2011-03-30 | 宁波金远东工业科技有限公司 | Low-energy consumption urea evaporator |
| CN104402769A (en) * | 2014-12-04 | 2015-03-11 | 重庆建峰化工股份有限公司 | Production process for Adblue |
| CN104829494A (en) * | 2015-05-27 | 2015-08-12 | 四川金象赛瑞化工股份有限公司 | Energy-saving urea production system and production process thereof |
| CN205084428U (en) * | 2015-11-06 | 2016-03-16 | 上海中腾环保科技有限公司 | A MVR evaporimeter for urea solution cryoconcentration |
| CN205307829U (en) * | 2015-12-03 | 2016-06-15 | 中化重庆涪陵化工有限公司 | Energy -conserving urea vaporization system |
-
2017
- 2017-08-22 CN CN201710724273.4A patent/CN107286058B/en active Active
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1749242A (en) * | 2005-08-03 | 2006-03-22 | 四川泸天化股份有限公司 | Method for concentrating thin urine using falling film type evaporation heater |
| CN101239268A (en) * | 2008-03-21 | 2008-08-13 | 李洪林 | Method and device for recovering dust of urea granulation |
| CN101991962A (en) * | 2009-08-21 | 2011-03-30 | 宁波金远东工业科技有限公司 | Low-energy consumption urea evaporator |
| CN201525815U (en) * | 2009-09-30 | 2010-07-14 | 宁波金远东工业科技有限公司 | Device for preparing urea by utilizing aqueous solution total recycle process |
| CN104402769A (en) * | 2014-12-04 | 2015-03-11 | 重庆建峰化工股份有限公司 | Production process for Adblue |
| CN104829494A (en) * | 2015-05-27 | 2015-08-12 | 四川金象赛瑞化工股份有限公司 | Energy-saving urea production system and production process thereof |
| CN205084428U (en) * | 2015-11-06 | 2016-03-16 | 上海中腾环保科技有限公司 | A MVR evaporimeter for urea solution cryoconcentration |
| CN205307829U (en) * | 2015-12-03 | 2016-06-15 | 中化重庆涪陵化工有限公司 | Energy -conserving urea vaporization system |
Non-Patent Citations (3)
| Title |
|---|
| 尿素真空蒸发控制的改造;刘立群等;《大氮肥》;20070831;第30卷(第4期);234-236 * |
| 尿素装置复杂控制系统简析与仪表调试;厉桂萍;《机械》;20091231;第36卷(第6期);66-69 * |
| 年产4万吨尿素装置自控通用设计的改进;陈令强;《炼油化工自动化》;19930829;21-24 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107286058A (en) | 2017-10-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107286058B (en) | Urea first-stage evaporation control system and method | |
| US8887549B2 (en) | Valve leakby diagnostics | |
| CN208634792U (en) | A kind of steam pipe line stable-pressure device | |
| JP2013156801A5 (en) | ||
| CN103173593B (en) | Molten steel vacuum refining system based on mechanical pump group | |
| TW200519360A (en) | Systems and methods for measurement of low liquid flow rates | |
| CN109108001B (en) | Automatic purging device and purging method for differential pressure measurement pipeline of demister of desulfurizing tower | |
| CN102650369A (en) | Liquefied natural gas filling pry | |
| CN107575748B (en) | Steam Tracing Device | |
| CN101702084B (en) | High-temperature and high-pressure water circulation control system and control method thereof | |
| CN104906993A (en) | Gas automatic blending device and blending method | |
| CN203705250U (en) | Heating digestion thermostat device with automatic liquid adding and flushing functions | |
| JP5216039B2 (en) | Gas hydrate rate measuring apparatus and control method thereof | |
| CN107934918B (en) | Oxygen generation control system of PSA oxygenerator | |
| CN204638022U (en) | One joins ammonia device automatically | |
| CN107300933B (en) | Urea evaporation concentration control system and method | |
| CN207473428U (en) | One kind is based on PLC automatic nitrogen control systems | |
| CN202580627U (en) | Liquefied natural gas feeding pry | |
| CN109885107B (en) | Method and device for correcting flow coefficient of control valve | |
| CN204619909U (en) | The automatic mixing device of a kind of methane gas | |
| CN213517988U (en) | Automatic sampling control system | |
| CN204803005U (en) | Be arranged in industry hydrogen peroxide solution production process on -line measuring and continuous acidification device | |
| CN104615168B (en) | Liquid chlorine gasification device pressure automatic control system | |
| CN204824171U (en) | Automatic hydrogenation purification device of nitrogen gas | |
| CN207176085U (en) | A kind of fully automatic high temperature high pressure desorbing electrolytic control system |
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 |