阅读说明：本技术 一种贫液再生自动优化在线调节系统及其方法 (Automatic optimization online adjusting system and method for barren liquor regeneration ) 是由 雷云 于 2019-10-24 设计创作，主要内容包括：本发明提出了一种贫液再生自动优化在线调节系统及其方法,该系统包括竖直安置的贫液比重测量筒以及安置在所述贫液比重测量筒上的压差变送器,压差变送器的压差信号输出端与控制器的压差信号输入端相连,贫液比重测量筒的贫液进口与贫液泵的贫液出口相连,贫液比重测量筒的贫液出口与贫液泵的贫液进口相连；贫液比重测量筒装满贫液时的压强小于或者等于CO<Sub>2</Sub>吸收塔内的压强。本发明能够操作过程的数据比手工分析更及时准确,且连续性大提高；能适应各种生产工况的要求,消除了手工分析存在的误差问题。(The invention provides an automatic optimization online adjusting system for barren liquor regeneration and a method thereof, wherein the system comprises a barren liquor specific gravity measuring cylinder which is vertically arranged and a differential pressure transmitter which is arranged on the barren liquor specific gravity measuring cylinder, wherein the differential pressure signal output end of the differential pressure transmitter is connected with the differential pressure signal input end of a controller, a barren liquor inlet of the barren liquor specific gravity measuring cylinder is connected with a barren liquor outlet of a barren liquor pump, and a barren liquor outlet of the barren liquor specific gravity measuring cylinder is connected with a barren liquor inlet of the barren liquor pump; the pressure of the lean solution when the specific gravity measuring cylinder is filled with the lean solution is less than or equal to CO 2 Absorbing the pressure in the tower. The invention canThe data of the operation process is more timely and accurate than manual analysis, and the continuity is greatly improved; can meet the requirements of various production working conditions, and eliminates the error problem existing in manual analysis.)

1. The lean solution regeneration automatic optimization online adjusting system is characterized by comprising a lean solution outlet of a regeneration tower connected with a lean solution inlet of a lean solution water cooler, a lean solution outlet of the lean solution water cooler connected with a lean solution inlet of a lean solution pump, and a lean solution outlet of the lean solution pump connected with a lean solution inlet of a CO removal pump ₂The absorption tower is connected with a pipeline; the device is characterized by also comprising a vertically arranged barren liquor specific gravity measuring cylinder and a differential pressure transmitter arranged on the barren liquor specific gravity measuring cylinder, wherein the differential pressure signal output end of the differential pressure transmitter is connected with the differential pressure signal input end of a controller, a barren liquor inlet of the barren liquor specific gravity measuring cylinder is connected with a barren liquor outlet of a barren liquor pump, and a barren liquor outlet of the barren liquor specific gravity measuring cylinder is connected with a barren liquor inlet of the barren liquor pump; the pressure of the lean solution when the specific gravity measuring cylinder is filled with the lean solution is less than or equal to CO ₂Absorbing the pressure in the tower.

2. The automatic lean solution regeneration optimization online regulating system according to claim 1, further comprising an air evacuation pipe provided at a lean solution outlet of the lean solution specific gravity measuring cylinder, and a first switching valve provided on the air evacuation pipe;

or/and a lean solution emptying maintenance pipeline is arranged at a lean solution inlet of the lean solution specific gravity measuring cylinder, and a second switch valve is arranged on the lean solution emptying maintenance pipeline.

3. The lean regeneration auto-optimizing on-line conditioning system of claim 1, further comprising CO removal ₂A first flow transmitter and a first flow regulating valve are arranged on the pipeline of the absorption tower, the flow signal output end of the first flow transmitter is connected with the first flow signal input end of the controller, and the first control signal output end of the controller is connected with the control signal input end of the first flow regulating valve;

or/and a lean solution manual sampling point is arranged at a lean solution inlet of the lean solution pump.

4. The lean water regeneration automatic optimization online regulation system of claim 1, further comprising a lean water outlet pipeline of the regeneration tower connected to a lean water outlet pipeline of a lean water cooler;

or/and the circulating water inlet of the lean liquid water cooler is connected with a pipeline from a circulating water system, the circulating water outlet of the lean liquid water cooler is connected with the inlet of the temperature regulating valve, the outlet of the temperature regulating valve is connected with a pipeline of a water circulation removing system, the temperature signal output end of the temperature regulating valve is connected with the temperature signal input end of the controller, and the sixth control signal output end of the controller is connected with the control signal input end of the temperature regulating valve.

5. The lean liquid regeneration automatic optimization online regulating system according to claim 1, further comprising a circulation outlet of the separator connected to a circulation inlet of a regeneration tower top condensate pump, a circulation outlet of the regeneration tower top condensate pump connected to a circulation inlet of a second flow regulating valve, a circulation outlet of the second flow regulating valve connected to a circulation inlet of a second flow transmitter, a circulation outlet of the second flow transmitter connected to a circulation inlet of the regeneration tower, a flow signal output end of the second flow transmitter connected to a second flow signal input end of the controller, a second control signal output end of the controller connected to a control signal input end of the second flow regulating valve, a circulation outlet of the regeneration tower connected to a circulation inlet of a regeneration tower top condenser, and a circulation outlet of the regeneration tower top condenser connected to a circulation inlet of the separator;

the outlet end of the separator is connected with the inlet end of a first pressure transmitter, the outlet end of the first pressure transmitter is connected with the first end of a first three-way joint, the pressure signal output end of the first pressure transmitter is connected with the first pressure signal input end of the controller, the second end of the first three-way joint is connected with the inlet end of a third flow regulating valve, and the outlet end of the third flow regulating valve is connected with the inlet end of a CO (carbon monoxide) flow regulating valve ₂The control signal input end of the third flow regulating valve is connected with the third control signal output end of the controller; the third end of the first three-way joint is connected with the inlet end of a second pressure transmitter, the outlet end of the second pressure transmitter is connected with the inlet end of a fourth flow regulating valve, and the pressure signal output end of the second pressure transmitter is connected with the controllerThe outlet end of a fourth flow regulating valve is connected with a urea removal device pipeline, and the control signal input end of the fourth flow regulating valve is connected with the fourth control signal output end of the controller;

the first outlet end of the regeneration tower is connected with a low-temperature waste boiler removing pipeline, the first inlet end of the regeneration tower is connected with a pipeline from the absorption tower, the second outlet end of the regeneration tower is connected with a flash evaporation tank removing pipeline, the third outlet end of the regeneration tower is connected with a reboiler removing pipeline, and the second inlet end of the regeneration tower is connected with a reboiler removing pipeline.

6. The online lean solution regeneration automatic optimization regulating system according to claim 5, further comprising a first outlet of the regeneration tower connected to an inlet of a fifth flow regulating valve, an outlet of the fifth flow regulating valve connected to an inlet of a fifth flow transmitter, a control signal input of the fifth flow regulating valve connected to a fifth control signal output of the controller, an outlet of the fifth flow transmitter connected to a third outlet of the regeneration tower, and a flow signal output of the fifth flow transmitter connected to a fifth flow signal input of the controller.

7. The online conditioning system for automatic optimization of barren liquor regeneration according to claim 6, further comprising a first liquid level transmitter disposed on the regeneration tower, wherein a liquid level signal output terminal of the first liquid level transmitter is connected to a regeneration tower liquid level signal input terminal of the controller;

and the liquid level signal output end of the second liquid level transmitter is connected with the separator liquid level signal input end of the controller.

8. The adjusting method of the lean liquor regeneration automatic optimization online adjusting system according to one of claims 1 to 7, characterized by comprising the following steps:

s1, obtaining the relation between the percentage value of the total potassium concentration of the barren solution in the barren solution specific gravity measuring cylinder and the differential pressure measured by the differential pressure transmitter;

s2, according to the CO to be input ₂Obtaining the water addition amount according to the total potassium concentration of the barren solution of the absorption tower;

and S3, adjusting the opening degree of the first flow regulating valve and the fifth flow regulating valve, and correcting the total potassium concentration of the lean solution.

9. The method of claim 8, wherein the step of obtaining the relationship between the total potassium concentration of the lean solution and the pressure difference in step S1 comprises the steps of:

s11, synchronously collecting corresponding manual analysis data of the total potassium concentration of the barren solution under different pressure differences;

s12, storing all the collected data in an Excel document in two rows, sorting all the data from small to large, and drawing a scatter diagram by using Excel for the two rows of data;

s13, adding a trend line to derive a calculation formula of the relation between the total potassium concentration of the barren solution and the pressure difference on the trend line; the calculation formula of the relation between the total potassium concentration of the barren solution and the pressure difference is as follows:

WIC303＝a*PDI303-b，

the PDI303 is the lean solution pressure difference in the lean solution specific gravity measuring cylinder measured on line by the pressure difference transmitter;

WIC303 is the percentage value of the total potassium concentration of the barren solution measured on line;

or/and in order to reduce the error of the online measurement of the total potassium of the lean solution caused by the temperature change, the lean solution temperature monitored by the temperature regulating valve is used for automatically regulating the opening degree of the lean solution regulating valve to control the circulating water quantity of the lean solution water cooler, so that the purpose of automatically regulating the lean solution temperature is realized, namely the error of the online analysis of the lean solution is eliminated.

10. The adjusting method of the lean solution regeneration automatic optimization online adjusting system according to claim 8, wherein in step S2, the water addition amount is calculated by:

Q＝(WIC303*FIC304/WIX303)-FIC304，

WIC303 is the percentage value of the total potassium concentration of the barren solution measured on line;

FIC304 is the lean flow measured by the first flow transmitter;

WIX303 is CO to be input ₂The total potassium concentration of the barren solution of the absorption tower;

q is the calculated water addition amount;

or/and in step S3, the calculation method of the correction value of the lean solution total potassium concentration is:

FFY315＝FIC304*WIC303/(FIC304+FIC315)，

FFY315 is a correction value for calculating the total potassium of the barren solution on line;

FIC304 is the lean flow measured by the first flow transmitter;

WIC303 is the percentage value of the total potassium concentration of the barren solution measured on line;

FIC315 is the flow measured by the fifth flow transmitter.

Technical Field

The invention relates to the technical field of barren solution concentration adjustment, in particular to a barren solution regeneration automatic optimization online adjustment system and a barren solution regeneration automatic optimization online adjustment method.

Background

The design capacity of the nitrogen fertilizer plant synthetic ammonia of the company is 650 t/d. The total process flow is as follows: the method comprises the steps that the external natural gas firstly enters a natural gas distribution station, the natural gas is metered, pressure-regulated, impurity-removed and primarily desulfurized in the distribution station, and then the liquid ammonia is finally obtained through natural gas compression, high-temperature desulfurization, heat exchange type one-stage and two-stage steam conversion, carbon monoxide conversion, carbon dioxide removal, deep methanation purification, synthesis gas compression, ammonia synthesis and freezing separation. Wherein the carbon dioxide is removed by adopting an improved hot potash decarburization process technology with low energy consumption. It is composed of two-stage absorption, two-stage regeneration and four-stage jet suction flash evaporation. The rich liquid from the absorption tower is sent to the top of the regeneration tower after energy is recovered by a hydraulic turbine, and the solution is in countercurrent contact with steam downwards in the regeneration tower, so that CO2 in the decarbonized rich liquid is regenerated. The regenerated hot potassium alkali liquor (barren liquor) is sent to a barren liquor water cooler from the bottom of the regeneration tower to be cooled to 70 ℃, and enters the absorption CO2 gas from the top of the absorption tower after being pressurized by a barren liquor pump. After the barren solution is cooled, a field manual sampling point is arranged to analyze indexes of all components of the barren solution such as total potassium and the like so as to guide production operation adjustment. Because of the traditional improved hot potash decarburization process, the monitoring means of the components of the solution is to manually sample on site and send the sample back to the analysis chamber for analysis, no special on-line analysis instrument is available to detect the specific components of the solution, and the analysis chamber needs to be taken back to analyze by adopting corresponding methods of various components. This presents the following problems:

(1) in manual analysis or manual instrumental analysis, various errors of different degrees exist in each ring segment of field sampling, sample weighing, sample dilution, color ratio in the analysis process and the like due to individual reasons, and the errors cannot be completely avoided.

(2) The manual analysis has poor continuity, each analysis result of each group is subjected to sampling, analysis and other links, the analysis process is long, and the analysis data has high hysteresis.

(3) The results of manual analysis only represent the results of samples at a certain time point during sampling, but cannot completely represent each continuous result of each variation process of production, and the real-time performance is poor.

(4) After the analysis result is often generated in the production process, the production condition is not guided, and although the assessment strength of an analyst and a post operator is strengthened in management, the problem that the analysis data is not matched with the data judged in the production process is verified and solved, so that the production is greatly influenced.

(5) The lean solution total potassium can not be automatically adjusted on line, the operation hysteresis is very large, and the production fluctuation is large.

(6) The liquid level at the bottom of the regeneration tower is not automatically adjusted, and when the pure flow adjustment is adopted, if the liquid level is not found timely, the liquid level at the bottom of the regeneration tower is easy to evacuate or is too high, so that production accidents are caused.

(7) The liquid level of the separator is not automatically adjusted, and when the pure flow adjustment is adopted, if the liquid level is not found timely, the liquid level at the bottom of the regeneration tower is easy to evacuate or the liquid level is too high, so that production accidents are caused.

(8) The concentration difference between the barren solution and the semi-barren solution regenerated by the regeneration tower is large and unstable, the stability of production operation is seriously influenced, the concentration of the barren solution often exceeds the design index due to untimely operation, equipment is seriously corroded, iron ions in the solution of the system seriously exceed the index, and other serious consequences are caused.

Disclosure of Invention

The invention aims to at least solve the technical problems in the prior art, and particularly innovatively provides an automatic optimization online adjusting system and method for barren liquor regeneration.

In order to achieve the above object, the present invention provides an online adjusting system for automatically optimizing the regeneration of lean solution, which comprises a lean solution outlet of a regeneration tower connected with a lean solution inlet of a lean solution water cooler, a lean solution outlet of the lean solution water cooler connected with a lean solution inlet of a lean solution pump, and a lean solution outlet of the lean solution pump connected with a CO removal outlet ₂The absorption tower is connected with a pipeline; the device also comprises a vertically arranged barren liquor specific gravity measuring cylinder and a differential pressure transmitter arranged on the barren liquor specific gravity measuring cylinder, wherein the differential pressure signal output end of the differential pressure transmitter is connected with the differential pressure signal input end of a controller, a barren liquor inlet of the barren liquor specific gravity measuring cylinder is connected with a barren liquor outlet of a barren liquor pump, and a barren liquor outlet of the barren liquor specific gravity measuring cylinder is connected with a barren liquor inlet of the barren liquor pump; the pressure of the lean solution when the specific gravity measuring cylinder is filled with the lean solution is less than or equal to CO ₂Absorbing the pressure in the tower. The concentration of the total lean solution price is measured by measuring the pressure difference in the lean solution specific gravity measuring cylinder.

In a preferred embodiment of the present invention, the method further comprises providing an air evacuation pipe at the lean liquid outlet of the lean liquid specific gravity measuring cylinder, and providing a first on-off valve on the air evacuation pipe; before filling the lean liquid specific gravity measuring cylinder, the first switch valve is in an open state, and when the air exhaust pipeline is filled with liquid, the lean liquid specific gravity measuring cylinder is filled, and the first switch valve is in a closed state.

Or/and a lean solution emptying maintenance pipeline is arranged at a lean solution inlet of the lean solution specific gravity measuring cylinder, and a second switch valve is arranged on the lean solution emptying maintenance pipeline. When the barren liquor specific gravity measuring cylinder is in fault and needs to be maintained, the liquid in the barren liquor specific gravity measuring cylinder can be emptied only by manually opening the second switch valve, and the maintenance is convenient.

In a preferred embodiment of the invention, the method further comprises removing CO ₂A first flow transmitter and a first flow regulating valve are arranged on the pipeline of the absorption tower, the flow signal output end of the first flow transmitter is connected with the first flow signal input end of the controller, and the first control signal output end of the controller is connected with the control signal input end of the first flow regulating valve; the flow rate measured by the first flow transmitter adjusts the opening degree of the first flow rate adjustment valve.

Or/and a lean solution manual sampling point is arranged at a lean solution inlet of the lean solution pump. The sixth switch valve is convenient to open, so that the total potassium of the lean solution is sampled, and the total potassium concentration of the lean solution is measured.

In a preferred embodiment of the present invention, the lean liquid outlet pipe of the regeneration tower is connected to the lean liquid outlet pipe of the lean liquid water cooler; when the temperature value of the total potassium of the barren solution flowing out of the regeneration tower is smaller than or equal to a preset first temperature threshold value, closing the seventh switch valve and the eighth switch valve, and opening the ninth switch valve; so that the lean solution total potassium is pumped into a lean solution pump.

Or/and the circulating water inlet of the lean liquid water cooler is connected with a pipeline from a circulating water system, the circulating water outlet of the lean liquid water cooler is connected with the inlet of the temperature regulating valve, the outlet of the temperature regulating valve is connected with a pipeline of a water circulation removing system, the temperature signal output end of the temperature regulating valve is connected with the temperature signal input end of the controller, and the sixth control signal output end of the controller is connected with the control signal input end of the temperature regulating valve. In order to reduce the error caused by the temperature change of the online measurement of the total potassium in the lean solution, an automatic lean solution temperature adjusting system is further arranged, the circulating water quantity of a lean solution water cooler is automatically adjusted by a temperature adjusting valve TV310 according to the lean solution temperature, and the purpose of automatically adjusting the lean solution temperature of the valve is achieved, namely the error of online lean solution analysis is eliminated.

In a preferred embodiment of the invention, the system further comprises a circulation outlet of the separator connected with a circulation inlet of a regeneration tower top condensate pump, a circulation outlet of the regeneration tower top condensate pump connected with a circulation inlet of a second flow regulating valve, a circulation outlet of the second flow regulating valve connected with a circulation inlet of a second flow transmitter, a circulation outlet of the second flow transmitter connected with a circulation inlet of the regeneration tower, a flow signal output end of the second flow transmitter connected with a second flow signal input end of a controller, a second control signal output end of the controller connected with a control signal input end of the second flow regulating valve, a circulation outlet of the regeneration tower connected with a circulation inlet of a regeneration tower top condenser, and a circulation outlet of the regeneration tower top condenser connected with a circulation inlet of the separator;

the outlet end of the separator is connected with the inlet end of a first pressure transmitter, the outlet end of the first pressure transmitter is connected with the first end of a first three-way joint, the pressure signal output end of the first pressure transmitter is connected with the first pressure signal input end of the controller, the second end of the first three-way joint is connected with the inlet end of a third flow regulating valve, and the outlet end of the third flow regulating valve is connected with the inlet end of a CO (carbon monoxide) flow regulating valve ₂The control signal input end of the third flow regulating valve is connected with the third control signal output end of the controller; the third end of the first tee joint is connected with the inlet end of a second pressure transmitter, the outlet end of the second pressure transmitter is connected with the inlet end of a fourth flow regulating valve, the pressure signal output end of the second pressure transmitter is connected with the second pressure signal input end of the controller, the outlet end of the fourth flow regulating valve is connected with a urea removal device pipeline, and the control signal input end of the fourth flow regulating valve is connected with the fourth control signal output end of the controller;

the first outlet end of the regeneration tower is connected with a low-temperature waste boiler removing pipeline, the first inlet end of the regeneration tower is connected with a pipeline from the absorption tower, the second outlet end of the regeneration tower is connected with a flash evaporation tank removing pipeline, the third outlet end of the regeneration tower is connected with a reboiler removing pipeline, and the second inlet end of the regeneration tower is connected with a reboiler removing pipeline.

In a preferred embodiment of the present invention, the regeneration tower further includes a first outlet of the regeneration tower connected to an inlet of a fifth flow control valve, an outlet of the fifth flow control valve connected to an inlet of a fifth flow transmitter, a control signal input of the fifth flow control valve connected to a fifth control signal output of the controller, an outlet of the fifth flow transmitter connected to a third outlet of the regeneration tower, and a flow signal output of the fifth flow transmitter connected to a fifth flow signal input of the controller. The water added at the washing section at the top of the regeneration tower is automatically added into a lean solution pipeline of a reboiler, a fifth flow transmitter FT315 is arranged and used for metering the water adding amount, the water adding amount is automatically adjusted by a fifth flow adjusting valve FV315, and cascade automatic control is performed by the fifth flow adjusting valve FV315 and the online measured lean solution total potassium, so that the water adding amount can be automatically adjusted by only setting a specific lean solution total potassium value in the cascade control, and the purpose of automatically adjusting the lean solution total potassium in real time by the fifth flow adjusting valve FV315 is realized.

In a preferred embodiment of the present invention, the system further comprises a first liquid level transmitter disposed on the regeneration tower, wherein a liquid level signal output end of the first liquid level transmitter is connected to a regeneration tower liquid level signal input end of the controller; set up first liquid level changer bottom the regeneration tower, when the regeneration tower bottom liquid level manage to find time or the liquid level is too high, in time close or transfer big first flow control valve opening, avoid causing the production accident to take place.

And the liquid level signal output end of the second liquid level transmitter is connected with the separator liquid level signal input end of the controller. The second liquid level transmitter is arranged at the bottom of the separator, and when the liquid level at the bottom of the separator is pumped out or too high, the opening degree of the second flow regulating valve is closed or increased in time, so that production accidents are avoided.

The invention also discloses an adjusting method of the barren liquor regeneration automatic optimization online adjusting system, which comprises the following steps:

s1, obtaining the relation between the percentage value of the total potassium concentration of the barren solution in the barren solution specific gravity measuring cylinder and the differential pressure measured by the differential pressure transmitter;

s2, according to the CO to be input ₂Obtaining the water addition amount according to the total potassium concentration of the barren solution of the absorption tower;

and S3, adjusting the opening degree of the first flow regulating valve and the fifth flow regulating valve, and correcting the total potassium concentration of the lean solution.

In a preferred embodiment of the present invention, the obtaining of the relationship between the total potassium concentration of the lean solution and the pressure difference in step S1 includes the steps of:

s11, synchronously collecting corresponding manual analysis data of the total potassium concentration of the barren solution under different pressure differences;

s12, storing all the collected data in an Excel document in two rows, sorting all the data from small to large, and drawing a scatter diagram by using Excel for the two rows of data;

s13, adding a trend line to derive a calculation formula of the relation between the total potassium concentration of the barren solution and the pressure difference on the trend line; the calculation formula of the relation between the total potassium concentration of the barren solution and the pressure difference is as follows:

WIC303＝a*PDI303-b，

the PDI303 is the lean solution pressure difference in the lean solution specific gravity measuring cylinder measured on line by the pressure difference transmitter;

WIC303 is the percentage value of the total potassium concentration of the barren solution measured on line;

or/and in order to reduce the error of the online measurement of the total potassium of the lean solution caused by the temperature change, the lean solution temperature monitored by the temperature regulating valve is used for automatically regulating the opening degree of the lean solution regulating valve to control the circulating water quantity of the lean solution water cooler, so that the purpose of automatically regulating the lean solution temperature is realized, namely the error of the online analysis of the lean solution is eliminated.

In a preferred embodiment of the present invention, in step S2, the method for calculating the water addition amount is:

Q＝(WIC303*FIC304/WIX303)-FIC304，

WIC303 is the percentage value of the total potassium concentration of the barren solution measured on line;

FIC304 is the lean flow measured by the first flow transmitter;

WIX303 is CO to be input ₂The total potassium concentration of the barren solution of the absorption tower;

q is the calculated water addition amount.

In a preferred embodiment of the present invention, in step S3, the calculation method of the correction value of the lean solution total potassium concentration is:

FFY315＝FIC304*WIC303/(FIC304+FIC315)，

FFY315 is a correction value for calculating the total potassium of the barren solution on line;

FIC304 is the lean flow measured by the first flow transmitter;

WIC303 is the percentage value of the total potassium concentration of the barren solution measured on line;

FIC315 is the flow measured by the fifth flow transmitter.

In conclusion, by adopting the technical scheme, the online real-time digital display of the barren solution total potassium in the production process can be realized, so that the operation process is more visual; the data of the operation process is more timely and accurate than manual analysis, and the continuity is greatly improved; the method can meet the requirements of various production working conditions, and the error problem existing in manual analysis is eliminated; the single control and the passive control of the original system are changed into the active advanced control, the fluctuation of the system is greatly reduced, the occurrence of accidents in the production process is reduced, and the safety production is greatly enhanced.

Additional aspects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

FIG. 1 is a schematic flow diagram of the present invention prior to its modification.

FIG. 2 is a schematic flow diagram of the present invention after modification.

Detailed Description

Reference will now be made in detail to embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to the same or similar elements or elements having the same or similar function throughout. The embodiments described below with reference to the accompanying drawings are illustrative only for the purpose of explaining the present invention, and are not to be construed as limiting the present invention.

The invention provides an automatic optimization online adjusting system for barren liquor regeneration, which comprises a barren liquor outlet of a regeneration tower connected with a barren liquor inlet of a barren liquor water cooler, a barren liquor outlet of the barren liquor water cooler connected with a barren liquor inlet of a barren liquor pump, and a barren liquor outlet of the barren liquor pump connected with a CO removal inlet ₂The absorption tower is connected with a pipeline; the device is characterized by also comprising a vertically arranged barren liquor specific gravity measuring cylinder and a differential pressure transmitter PDT303 arranged on the barren liquor specific gravity measuring cylinder, wherein the differential pressure signal output end of the differential pressure transmitter PDT303 is connected with the differential pressure signal input end of a controller, the barren liquor inlet of the barren liquor specific gravity measuring cylinder is connected with the barren liquor outlet of a barren liquor pump, and the barren liquor outlet of the barren liquor specific gravity measuring cylinder is connected with the barren liquor inlet of the barren liquor pump; the pressure of the lean solution when the specific gravity measuring cylinder is filled with the lean solution is less than or equal to CO ₂Absorbing the pressure in the tower. In the embodiment, the differential pressure measured by the differential pressure transmitter is in direct proportion to the density rho and the height H of the liquid, and when the liquid measurement height is fixed, the differential pressure measured by the differential pressure transmitter is only in direct proportion to the density of the liquid, so that the problem of measuring the density of the liquid can be changed into the problem of measuring the differential pressure by utilizing the characteristic. The lean liquid specific gravity measuring cylinder adopts a DN80 vertical installation pipeline with the length of 4.2 meters, the differential pressure transmitter adopts a diaphragm type differential pressure transmitter with the model of EJA118W, the range is 0-100 KPa, the center of the positive pressure chamber is arranged at a position 0.1 meter above the bottom of the measuring cylinder, the center of the negative pressure chamber is arranged at a position 0.1 meter below the top of the measuring cylinder, and the vertical height of the center of the positive pressure chamber and the negative pressure chamber of the transmitter is ensured to be 4 meters. After being cooled, the barren solution is pressurized by a barren solution pump to enter an absorption tower and is led out by 2m from an outlet of the barren solution pump ³The lean solution enters from the bottom of the measuring cylinder and flows through the measuring cylinder from bottom to top, and the lean solution flows out from the top of the measuring cylinder and returns to the inlet of the lean solution pump, so that the lean solution density measurement is completedThe process.

In a preferred embodiment of the present invention, the method further comprises providing an air evacuation pipe at the lean liquid outlet of the lean liquid specific gravity measuring cylinder, and providing a first on-off valve on the air evacuation pipe;

or/and a lean solution emptying maintenance pipeline is arranged at a lean solution inlet of the lean solution specific gravity measuring cylinder, and a second switch valve is arranged on the lean solution emptying maintenance pipeline. In the present embodiment, a fifth three-way joint, a sixth three-way joint, a fourth switch valve, and a tenth switch valve are provided on a pipe from the lean solution outlet of the lean solution pump to the lean solution inlet of the lean solution specific gravity measuring cylinder; a pipeline from the lean liquid outlet of the lean liquid water cooler to the lean liquid inlet of the lean liquid pump is provided with a seventh three-way joint, an eighth three-way joint, a thirteenth three-way joint, a fifth switch valve, a sixth switch valve and a seventh switch valve; a pipeline from the barren liquor outlet of the barren liquor specific gravity measuring cylinder to a barren liquor inlet of the barren liquor pump is provided with a third switch valve, a fifth switch valve, a sixth switch valve, a fourth three-way joint, a seventh three-way joint and a thirteenth switch joint, a pipeline from the barren liquor outlet of the regeneration tower to the barren liquor inlet of the barren liquor water cooler is provided with a ninth three-way joint and an eighth switch valve, and a pipeline from the barren liquor outlet of the regeneration tower to the barren liquor inlet of the barren liquor water cooler is provided with a seventh three-way joint, an eighth three-way joint, a ninth three-way joint, a thirteenth switch joint, a fifth switch valve, a sixth switch valve and a ninth switch valve; the concrete connection is as follows: the lean liquid outlet of the regeneration tower is connected with the first end of a ninth three-way joint, the second end of the ninth three-way joint is connected with the first end of an eighth switch valve, the second end of the eighth switch valve is connected with the lean liquid inlet of a lean liquid water cooler, the third end of the ninth three-way joint is connected with the first end of a ninth switch valve, the second end of the ninth switch valve is connected with the first end of an eighth three-way joint, the second end of the eighth three-way joint is connected with the first end of a seventh switch valve, the second end of the seventh switch valve is connected with the lean liquid outlet of the lean liquid water cooler, the third end of the eighth three-way joint is connected with the first end of a seventh three-way joint, the second end of the seventh three-way joint is connected with the first end of a third switch valve, and the second end of the third switch valve is connected with the third end of a fourth three-way jointOne end of the first three-way joint is connected with the first end of the first switch valve, the second end of the first switch valve is connected with the air emptying pipeline, and the third end of the first three-way joint is connected with the lean solution outlet of the lean solution specific gravity measuring cylinder; a third end of a seventh three-way joint is connected with a first end of a thirteenth three-way joint, a second end of the thirteenth three-way joint is connected with a first end of a sixth switch valve, a first end of the sixth switch valve is connected with a lean liquid manual sampling pipeline, a third end of the thirteenth three-way joint is connected with a first end of a fifth switch valve, a second end of the fifth switch valve is connected with a lean liquid inlet of a lean liquid pump, a lean liquid outlet of the lean liquid pump is connected with a first end of a fourth switch valve, a second end of the fourth switch valve is connected with a first end of a sixth three-way joint, a second end of the sixth three-way joint is connected with a first end of a tenth switch valve, a second end of the tenth switch valve is connected with a first end of a fifth three-way joint, a second end of the fifth three-way joint is connected with a first end of a second switch valve, a second end of the second switch valve is connected with a lean liquid emptying and overhauling pipeline, and a third end of the fifth three-way joint is connected with a lean liquid specific gravity measuring cylinder, the third end of the sixth three-way joint is connected to the first end of the first flow rate regulating valve FV304, the second end of the first flow rate regulating valve FV304 is connected to the first end of the first flow transmitter FT304, and the second end of the first flow transmitter FT304 is connected to the CO removal unit FT304 ₂The absorption tower is connected with a pipeline, the flow signal output end of the first flow transmitter FT304 is connected with the first flow signal input end of the controller, and the first control signal output end of the controller is connected with the control signal input end of the first flow regulating valve FV 304. Other three-way joints and switching valves are not described herein, such as an eleventh switching valve disposed between the temperature regulating valve and the lean water cooler. The first to eleventh switch valves are preferably manual valves, which can save cost, and electromagnetic valves can also be adopted.

In a preferred embodiment of the invention, the method further comprises removing CO ₂A first flow transmitter FT304 and a first flow regulating valve FV304 are arranged on the pipeline of the absorption tower, the flow signal output end of the first flow transmitter FT304 is connected with the first flow signal input end of a controller, and the first control signal output end of the controllerIs connected with the control signal input end of the first flow regulating valve FV 304;

or/and a lean solution manual sampling point is arranged at a lean solution inlet of the lean solution pump.

In a preferred embodiment of the present invention, the lean liquid outlet pipe of the regeneration tower is connected to the lean liquid outlet pipe of the lean liquid water cooler;

or/and a circulating water inlet of the lean water cooler is connected with a pipeline from a circulating water system, a circulating water outlet of the lean water cooler is connected with an inlet of a temperature regulating valve TV310, an outlet of the temperature regulating valve TV310 is connected with a circulating water removing system pipeline, a temperature signal output end of the temperature regulating valve TV310 is connected with a temperature signal input end of a controller, and a sixth control signal output end of the controller is connected with a control signal input end of the temperature regulating valve TV 310.

In a preferred embodiment of the invention, the recycling outlet of the separator is connected with the recycling inlet of a recycling overhead condensate pump, the recycling outlet of the recycling overhead condensate pump is connected with the recycling inlet of a second flow regulating valve FV314, the recycling outlet of the second flow regulating valve FV314 is connected with the recycling inlet of a second flow transmitter FT314, the recycling outlet of the second flow transmitter FT314 is connected with the recycling inlet of the recycling tower, the flow signal output end of the second flow transmitter FT314 is connected with the second flow signal input end of a controller, the second control signal output end of the controller is connected with the control signal input end of the second flow regulating valve FV314, the recycling outlet of the recycling tower is connected with the recycling inlet of a recycling overhead condenser, and the recycling outlet of the recycling overhead condenser is connected with the recycling inlet of the separator;

the outlet end of the separator is connected with the inlet end of a first pressure transmitter PT308, the outlet end of the first pressure transmitter PT308 is connected with the first end of a first three-way joint, the pressure signal output end of the first pressure transmitter PT308 is connected with the first pressure signal input end of the controller, the second end of the first three-way joint is connected with the inlet end of a third flow regulating valve FV308, the outlet end of the third flow regulating valve FV308 is connected with the inlet end of the CO ₂The emptying pipelines are connected, and the control signal input end of a third flow regulating valve FV308The third control signal output end of the controller is connected with the first control signal output end of the controller; the third end of the first three-way joint is connected with the inlet end of a second pressure transmitter PT307, the outlet end of the second pressure transmitter PT307 is connected with the inlet end of a fourth flow regulating valve FV307, the pressure signal output end of the second pressure transmitter PT307 is connected with the second pressure signal input end of the controller, the outlet end of the fourth flow regulating valve FV307 is connected with a urea removal device pipeline, and the control signal input end of the fourth flow regulating valve FV307 is connected with the fourth control signal output end of the controller;

the first outlet end of the regeneration tower is connected with a low-temperature waste boiler removing pipeline, the first inlet end of the regeneration tower is connected with a pipeline from the absorption tower, the second outlet end of the regeneration tower is connected with a flash evaporation tank removing pipeline, the third outlet end of the regeneration tower is connected with a reboiler removing pipeline, and the second inlet end of the regeneration tower is connected with a reboiler removing pipeline.

In a preferred embodiment of the present invention, the regeneration tower further comprises a first outlet of the regeneration tower connected to an inlet of a fifth flow control valve FV315, an outlet of the fifth flow control valve FV315 connected to an inlet of a fifth flow transmitter FT315, a control signal input of the fifth flow control valve FV315 connected to a fifth control signal output of the controller, an outlet of the fifth flow transmitter FT315 connected to a third outlet of the regeneration tower, and a flow signal output of the fifth flow transmitter FT315 connected to a fifth flow signal input of the controller. In the present embodiment, a second three-way joint is provided at the first outlet end of the regeneration tower, and a third three-way joint is provided at the third outlet end of the regeneration tower; the concrete connection is as follows: the first outlet end of the regeneration tower is connected with the first end of a second three-way joint, the second end of the second three-way joint is connected with a low-pressure-reducing waste boiler removing pipeline, the third end of the second three-way joint is connected with the inlet end of a fifth flow regulating valve FV315, the outlet end of the fifth flow regulating valve FV315 is connected with the inlet end of a fifth flow transmitter FT315, the control signal input end of the fifth flow regulating valve FV315 is connected with the fifth control signal output end of the controller, the outlet end of the fifth flow transmitter FT315 is connected with the first end of a third three-way joint, the flow signal output end of the fifth flow transmitter FT315 is connected with the fifth flow signal input end of the controller, the second end of the third three-way joint is connected with a reboiler removing pipeline, and the third end of the third three-way joint is connected with the third outlet end.

In a preferred embodiment of the invention, the system further comprises a first liquid level transmitter LT311 arranged on the regeneration tower, wherein a liquid level signal output end of the first liquid level transmitter LT311 is connected with a regeneration tower liquid level signal input end of the controller;

or/and a second liquid level transmitter LT318 arranged on the separator, wherein the liquid level signal output end of the second liquid level transmitter LT318 is connected with the separator liquid level signal input end of the controller.

The invention also discloses an adjusting method of the barren liquor regeneration automatic optimization online adjusting system, which comprises the following steps:

s1, obtaining the relation between the percentage value of the total potassium concentration of the barren solution in the barren solution specific gravity measuring cylinder and the differential pressure measured by the differential pressure transmitter;

s2, according to the CO to be input ₂Obtaining the water addition amount according to the total potassium concentration of the barren solution of the absorption tower;

s3, the opening degrees of the first flow rate adjustment valve FV304 and the fifth flow rate adjustment valve FV315 are adjusted to correct the total potassium concentration of the lean solution.

In a preferred embodiment of the present invention, the obtaining of the relationship between the total potassium concentration of the lean solution and the pressure difference in step S1 includes the steps of:

s11, synchronously collecting corresponding manual analysis data of the total potassium concentration of the barren solution under different pressure differences;

s12, storing all the collected data in an Excel document in two rows, sorting all the data from small to large, and drawing a scatter diagram by using Excel for the two rows of data;

s13, adding a trend line to derive a calculation formula of the relation between the total potassium concentration of the barren solution and the pressure difference on the trend line; the calculation formula of the relation between the total potassium concentration of the barren solution and the pressure difference is as follows:

WIC303＝a*PDI303-b，

wherein a is a constant first variable and takes the value of 1.996;

b is a constant second variable and takes the value of 69.1;

PDI303 is the lean solution pressure difference in the lean solution specific gravity measuring cylinder measured on line by a pressure difference transmitter PDT 303;

WIC303 is the percentage value of the total potassium concentration of the barren solution measured on line;

or/and in order to reduce the error of the online measurement of the total potassium of the lean solution caused by the temperature change, the lean solution temperature monitored by the temperature regulating valve is used for automatically regulating the opening degree of the lean solution regulating valve to control the circulating water quantity of the lean solution water cooler, so that the purpose of automatically regulating the lean solution temperature is realized, namely the error of the online analysis of the lean solution is eliminated.

In a preferred embodiment of the present invention, in step S2, the method for calculating the water addition amount is:

Q＝(WIC303*FIC304/WIX303)-FIC304，

WIC303 is the percentage value of the total potassium concentration of the barren solution measured on line;

FIC304 is the lean flow measured by the first flow transmitter FT 304;

WIX303 is CO to be input ₂The total potassium concentration of the barren solution of the absorption tower;

q is the calculated water addition amount.

In a preferred embodiment of the present invention, in step S3, the calculation method of the correction value of the lean solution total potassium concentration is:

FFY315＝FIC304*WIC303/(FIC304+FIC315)，

FFY315 is a correction value for calculating the total potassium of the barren solution on line;

FIC304 is the lean flow measured by the first flow transmitter FT 304;

WIC303 is the percentage value of the total potassium concentration of the barren solution measured on line;

FIC315 is the flow measured by fifth flow transmitter FT 315.

While embodiments of the invention have been shown and described, it will be understood by those of ordinary skill in the art that: various changes, modifications, substitutions and alterations can be made to the embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the claims and their equivalents.