CN114014395B - Liquid waste heat pump evaporation system and liquid level control method, control equipment and medium thereof - Google Patents
Liquid waste heat pump evaporation system and liquid level control method, control equipment and medium thereof Download PDFInfo
- Publication number
- CN114014395B CN114014395B CN202111307124.0A CN202111307124A CN114014395B CN 114014395 B CN114014395 B CN 114014395B CN 202111307124 A CN202111307124 A CN 202111307124A CN 114014395 B CN114014395 B CN 114014395B
- Authority
- CN
- China
- Prior art keywords
- waste liquid
- tower
- reflux
- evaporation
- concentrate
- 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
- 239000007788 liquid Substances 0.000 title claims abstract description 290
- 238000001704 evaporation Methods 0.000 title claims abstract description 149
- 230000008020 evaporation Effects 0.000 title claims abstract description 146
- 238000000034 method Methods 0.000 title claims abstract description 71
- 239000010808 liquid waste Substances 0.000 title description 2
- 239000002699 waste material Substances 0.000 claims abstract description 171
- 238000010992 reflux Methods 0.000 claims abstract description 146
- 239000012141 concentrate Substances 0.000 claims abstract description 80
- 230000001105 regulatory effect Effects 0.000 claims abstract description 37
- 230000001276 controlling effect Effects 0.000 claims abstract description 31
- 238000012545 processing Methods 0.000 claims description 34
- 230000004044 response Effects 0.000 claims description 13
- 239000002918 waste heat Substances 0.000 claims description 10
- 238000007664 blowing Methods 0.000 claims description 6
- 238000004891 communication Methods 0.000 claims description 6
- 230000003068 static effect Effects 0.000 claims description 4
- 238000004364 calculation method Methods 0.000 claims description 3
- 238000010586 diagram Methods 0.000 description 16
- 230000008569 process Effects 0.000 description 11
- 238000004590 computer program Methods 0.000 description 9
- 238000011068 loading method Methods 0.000 description 9
- 238000004519 manufacturing process Methods 0.000 description 9
- 238000010438 heat treatment Methods 0.000 description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 8
- 230000006870 function Effects 0.000 description 7
- 230000005540 biological transmission Effects 0.000 description 5
- 239000000463 material Substances 0.000 description 5
- 239000000306 component Substances 0.000 description 4
- 238000004821 distillation Methods 0.000 description 4
- 239000011344 liquid material Substances 0.000 description 4
- 230000009471 action Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- -1 salt ions Chemical class 0.000 description 3
- 238000003491 array Methods 0.000 description 2
- 238000007599 discharging Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 239000000835 fiber Substances 0.000 description 2
- 230000006872 improvement Effects 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 230000001902 propagating effect Effects 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 230000002730 additional effect Effects 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000002485 combustion reaction Methods 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 239000010949 copper Substances 0.000 description 1
- 239000008358 core component Substances 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000010612 desalination reaction Methods 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 239000002360 explosive Substances 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000006260 foam Substances 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 230000002269 spontaneous effect Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 230000007306 turnover Effects 0.000 description 1
- 239000012808 vapor phase Substances 0.000 description 1
- 238000009834 vaporization Methods 0.000 description 1
- 230000008016 vaporization Effects 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F1/00—Treatment of water, waste water, or sewage
- C02F1/02—Treatment of water, waste water, or sewage by heating
- C02F1/04—Treatment of water, waste water, or sewage by heating by distillation or evaporation
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2301/00—General aspects of water treatment
- C02F2301/04—Flow arrangements
- C02F2301/043—Treatment of partial or bypass streams
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2303/00—Specific treatment goals
- C02F2303/10—Energy recovery
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Hydrology & Water Resources (AREA)
- Engineering & Computer Science (AREA)
- Environmental & Geological Engineering (AREA)
- Water Supply & Treatment (AREA)
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)
- Heat Treatment Of Water, Waste Water Or Sewage (AREA)
Abstract
The present disclosure relates to a method for controlling a column bottom liquid level of a waste liquid heat pump evaporation system, a control device and a medium. The method comprises the following steps: at a control device, acquiring the current liquid level and concentration of waste liquid at the tower bottom of the evaporation tower, the flow of secondary steam output from the top of the evaporation tower and the feeding flow of the waste liquid; obtaining the reflux flow of the tower kettle of the distillate and the discharge of the concentrate; controlling at least one of a concentrate discharge valve and a tower kettle reflux valve so that the tower kettle reflux flow of the distillate is matched with the discharge amount of the concentrate; and adjusting the opening of a feeding regulating valve on a waste liquid feeding pipeline based on the obtained current liquid level of the waste liquid in the tower kettle, the flow of the secondary steam and the waste liquid feeding flow, so that the difference value between the current liquid level of the waste liquid in the tower kettle and the preset first liquid level is within a first preset range, and the waste liquid feeding pipeline is arranged between a feeding pump and a waste liquid preheater. The utility model discloses a can realize the accurate and stable control of the tower cauldron waste liquid level of evaporating tower.
Description
Technical Field
The present disclosure relates generally to heat pump evaporation treatment technology, and in particular, to a method for controlling a tank level of a waste liquid heat pump evaporation system, a control device, and a medium.
Background
For a heat pump evaporation treatment system for treating waste liquid which is inflammable, explosive, toxic and harmful, etc., in view of the risk of leakage of the waste liquid, the safety and reliability of the control technology for controlling the waste liquid heat pump evaporation system and the stability of operation are particularly important.
Because the heavy components or salt ions in the waste liquid can not volatilize generally, the water in the waste liquid can be vaporized into secondary steam through a heat pump evaporation system, distilled water is obtained through condensation, the heavy components or salt ions are left in the concentrated solution, and therefore the waste liquid can be treated through an evaporation concentration method, and the heavy components or salt ions can be concentrated in the concentrated solution for discharge so as to be further stored or treated. The level and stability of the waste liquid in the tower bottom of the evaporation tower, which is a core component of the heat pump evaporation system, can directly influence the evaporation effect of the waste liquid, for example, too high or too low liquid level in the waste liquid in the tower bottom easily causes too much foam to influence the gas-liquid separation effect or cause dry combustion. The traditional method for controlling the liquid level of the tower kettle of the waste liquid heat pump evaporation system is particularly used for controlling the liquid level of the waste liquid of the tower kettle of the evaporation tower by only adjusting the feeding flow of the waste liquid when controlling the liquid level of the waste liquid of the tower kettle of the evaporation tower. However, when the tower pressure fluctuates or the secondary steam flow changes, the liquid level of the waste liquid of the tower kettle is caused to fluctuate, so that the false liquid level is caused, and the liquid level control of the tower kettle is difficult to accurately and stably maintain at the liquid level set value.
In summary, the scheme of the traditional method for controlling the liquid level of the tower kettle of the waste liquid heat pump evaporation system has the defects that the fluctuation and false liquid level of the waste liquid caused by the fluctuation of the tower pressure are difficult to overcome, and the liquid level control of the tower kettle is not accurate and stable enough.
Disclosure of Invention
The disclosure provides a method for controlling the liquid level of a tower kettle of a waste liquid heat pump evaporation system, the waste liquid heat pump evaporation system, control equipment and medium, and can realize the accurate and stable control of the liquid level of the waste liquid of the tower kettle of an evaporation tower.
According to a first aspect of the present disclosure, a method for controlling a column sump level of a waste liquid heat pump evaporation system is provided. The waste liquid heat pump evaporation system at least comprises an evaporation tower, a waste liquid tank, a reboiler and control equipment, wherein waste liquid in the waste liquid tank is sent to the evaporation tower and the reboiler after passing through a feeding pump and a waste liquid preheater, at least part of distilled liquid is refluxed to the evaporation tower through a tower kettle reflux valve, and part of concentrated liquid of the evaporation tower is discharged out of the evaporation tower through a concentrated liquid discharge valve. The method comprises the following steps: at a control device, acquiring the current liquid level and concentration of waste liquid at the tower bottom of the evaporation tower, the flow of secondary steam output from the top of the evaporation tower and the feeding flow of the waste liquid; obtaining the reflux flow of the tower kettle of the distillate and the discharge of the concentrate; controlling at least one of a concentrate discharge valve and a tower kettle reflux valve so that the tower kettle reflux flow of the distillate is matched with the discharge amount of the concentrate; and adjusting the opening of a feeding regulating valve on a waste liquid feeding pipeline based on the obtained current liquid level of the waste liquid in the tower kettle, the flow of the secondary steam and the waste liquid feeding flow, so that the difference value between the current liquid level of the waste liquid in the tower kettle and the preset first liquid level is within a first preset range, and the waste liquid feeding pipeline is arranged between a feeding pump and a waste liquid preheater.
According to a second aspect of the present invention there is also provided a waste liquid heat pump evaporation system comprising: the waste liquid tank is used for storing waste liquid, and the waste liquid in the waste liquid tank is sent to the evaporation tower and the reboiler through the feeding regulating valve and the waste liquid preheater; the evaporation tower is used for performing evaporation operation on the waste liquid in the evaporation tower so as to generate secondary steam and concentrated solution; a concentrate discharge valve disposed on the concentrate discharge line for allowing the generated concentrate to be discharged out of the evaporation tower via the concentrate discharge valve; a column bottom reflux valve arranged on the column bottom reflux line for allowing at least part of the distillate to reflux to the evaporation column via the column bottom reflux valve, the concentrate discharge line and the column bottom reflux line being in communication with the bottom of the evaporation column; a reboiler for providing heat to the bottom of the evaporation tower; and a control device comprising at least one processing unit and at least one memory coupled to the at least one processing unit and storing instructions for execution by the at least one processing unit, which when executed by the at least one processing unit, cause the control device to perform the method of the first aspect of the disclosure.
According to a third aspect of the present invention, there is also provided a control apparatus. The control device includes at least one processing unit and at least one memory coupled to the at least one processing unit and storing instructions for execution by the at least one processing unit, the instructions when executed by the at least one processing unit cause the control device to perform the method of the first aspect of the disclosure.
According to a fourth aspect of the present disclosure, there is also provided a computer-readable storage medium. The computer-readable storage medium has stored thereon machine-executable instructions that, when executed, cause a machine to perform the method of the first aspect of the present disclosure.
In some embodiments, controlling at least one of the concentrate discharge valve and the bottoms reflux valve such that the bottoms reflux flow of the distillate matches the discharge of the concentrate comprises: determining whether the concentration of the waste liquid in the tower kettle is within a second preset range of a preset concentration set value; and in response to determining whether the concentration of the bottoms liquid is within a second predetermined range of the predetermined concentration set point, maintaining the concentrate discharge valve at the current opening.
In some embodiments, determining whether the concentration of the bottoms liquid is within a second predetermined range of the predetermined concentration set point comprises: calculating the density of the waste liquid in the tower kettle based on the current static pressure difference of a certain tower kettle liquid level measured by the blowing type liquid level meter; and determining whether the calculated concentration of the bottoms liquid is within a second predetermined range of the predetermined concentration set point by the liquid density.
In some embodiments, controlling at least one of the concentrate discharge valve and the bottoms reflux valve such that the bottoms reflux flow of the distillate matches the discharge of the concentrate further comprises: determining whether a difference between a bottoms reflux flow of the distillate and a discharge of the concentrate is greater than a predetermined threshold; in response to determining that the difference between the bottoms reflux flow of the distillate and the discharge of the concentrate is greater than a predetermined threshold, adjusting, via a valve positioner, an opening of a bottoms reflux regulating valve on a bottoms reflux line disposed between a bottoms of the evaporation tower and a top reflux line, based on the difference between the bottoms reflux flow of the distillate and the discharge of the concentrate; and determining that the bottoms reflux flow of the distillate matches the discharge of the concentrate in response to determining that the difference between the bottoms reflux flow of the distillate and the discharge of the concentrate is less than or equal to the predetermined threshold.
In some embodiments, adjusting the opening of the feed-in regulating valve on the waste liquid feed line so that the difference between the current level of the tower kettle waste liquid and the predetermined first level is within the first predetermined range comprises: determining whether a difference between a current liquid level of the waste liquid at the tower bottom of the evaporation tower and a preset first liquid level is within a first preset range, wherein the current liquid level of the waste liquid at the tower bottom is measured by a blowing type liquid level meter; determining the opening of a feeding regulating valve through PID calculation based on the obtained current liquid level of the waste liquid of the tower kettle, the flow rate of the secondary steam and the feeding flow rate of the waste liquid in response to determining that the difference between the current liquid level of the waste liquid of the tower kettle of the evaporation tower and the preset first liquid level is not in the first preset range; and adjusting a valve positioner of the feeding regulating valve based on the determined opening of the feeding regulating valve so that the difference between the current liquid level of the waste liquid in the tower kettle and the preset first liquid level is within a first preset range.
In some embodiments, the method for controlling the column bottoms level of a waste heat pump evaporation system further comprises: determining whether the reflux ratio of the evaporation tower is within a third preset range of the reflux ratio set value; and in response to determining that the reflux ratio of the evaporation column is not within the third predetermined range of the reflux ratio set point, adjusting the opening of the overhead reflux valve to control the flow rate of the overhead reflux distillate such that the reflux ratio is within the third predetermined range of the reflux ratio set point.
The summary is provided to introduce a selection of concepts in a simplified form that are further described below in the detailed description. This summary is not intended to identify key features or essential features of the disclosure, nor is it intended to be used to limit the scope of the disclosure.
Drawings
Fig. 1 shows a schematic diagram of a system for implementing a method of controlling a column bottoms level of a waste heat pump evaporation system, according to an embodiment of the present disclosure.
Fig. 2 shows a flow chart of a method for controlling a column bottoms level of a waste heat pump evaporation system, according to an embodiment of the disclosure.
Fig. 3 shows a schematic diagram of a waste liquid heat pump evaporation system according to an embodiment of the disclosure.
Fig. 4 shows a flow chart of a method for matching a bottoms reflux flow of a distillate to a discharge of a concentrate in accordance with an embodiment of the present disclosure.
Fig. 5 shows a flowchart of a method for controlling the reflux ratio of an evaporation tower according to an embodiment of the present disclosure.
Fig. 6 schematically illustrates a block diagram of an electronic device suitable for use in implementing embodiments of the present disclosure.
Like or corresponding reference characters indicate like or corresponding parts throughout the several views.
Detailed Description
Preferred embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While the preferred embodiments of the present disclosure are illustrated in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.
The term "comprising" and variations thereof as used herein means open ended, i.e., "including but not limited to. The term "or" means "and/or" unless specifically stated otherwise. The term "based on" means "based at least in part on". The terms "one example embodiment" and "one embodiment" mean "at least one example embodiment. The term "another embodiment" means "at least one additional embodiment". The terms "first," "second," and the like, may refer to different or the same object.
As described above, the conventional method for controlling the liquid level in the bottom of the evaporation system of the waste liquid heat pump generally controls the level of the waste liquid in the bottom of the evaporation tower by adjusting the feeding flow rate of the waste liquid only. However, when the tower pressure fluctuates or the secondary steam flow changes, the fluctuation of the liquid level of the waste liquid in the tower kettle is caused to cause false liquid level, so that the liquid level control of the tower kettle is difficult to accurately and stably control at the liquid level set value.
To at least partially address one or more of the above problems, as well as other potential problems, example embodiments of the present disclosure present an aspect of a method for controlling a column sump level of a waste liquid heat pump evaporation system. The method comprises the steps of obtaining the current liquid level and concentration of waste liquid at the tower bottom of an evaporation tower, the flow of secondary steam output from the top of the evaporation tower, the waste liquid feeding flow, the tower bottom reflux flow of distilled liquid and the discharge amount of concentrated liquid through control equipment; controlling at least one of a concentrate discharge valve and a tower kettle reflux valve so that the tower kettle reflux flow of the distillate is matched with the discharge amount of the concentrate; the method can effectively ensure conservation of materials of the reflux flow of the tower kettle of the distilled liquid entering the evaporation tower and the discharge amount of the concentrated liquid flowing out of the evaporation tower, so that interference brought by multi-strand feeding and discharging for liquid level control is avoided, and the complexity of liquid level control of the tower kettle is reduced. In addition, this disclosure is through confirming the aperture of the material loading governing valve on the waste liquid material loading pipeline based on the current liquid level of tower cauldron waste liquid, the flow of secondary steam, the waste liquid material loading flow of acquireing to the current liquid level of tower cauldron waste liquid reaches predetermined first liquid level, and this disclosure can realize the accurate and stable control of the tower cauldron waste liquid level of evaporating tower.
Fig. 1 illustrates a schematic diagram of a system 100 for a method of controlling a column bottoms level of a waste heat pump evaporation system, according to an embodiment of the present disclosure. As shown in fig. 1, the system 100 includes, for example, a control device 110 and a heat pump evaporation apparatus 120. The heat pump evaporation device 120 further comprises an evaporation tower 140, a waste liquid tank (not shown), a reboiler 130, a waste liquid preheater (waste liquid preheater includes, for example and without limitation, a primary preheater 134, a condensate cooler 136), a vapor compressor (not shown), and the like. The control device 110 may interact with a data acquisition unit (not shown), the heat pump evaporation means 120, in a wired or wireless manner via a communication system.
As regards the waste liquid tank, it is used for storing waste liquid. The waste liquid in the waste liquid tank is sent to the evaporation tower 140 and the reboiler 130 via the feed pump, the feed adjusting valve 132, the primary preheater 134, and the condensate cooler 136.
With respect to the waste stream preheater (e.g., primary preheater 134 and condensate cooler 136), it is used to preheat the waste stream from the waste stream tank.
Regarding the evaporation tower 140, it is used for performing an evaporation operation for the waste liquid in the evaporation tower 140 so that the waste liquid undergoes saturated boiling, and is separated into a secondary vapor (vapor phase) and a concentrated liquid (liquid phase). The top of the evaporation column 140 is connected to an overhead reflux line, and the distillate may flow into the evaporation column 140 via the overhead reflux line. The overhead return line 162 is provided with an overhead reflux on-off valve and an overhead reflux regulating valve (collectively, "overhead reflux valve", not shown in fig. 1). By adjusting the opening of the overhead reflux valve, the flow rate of the overhead reflux distillate can be controlled. The bottom (lower end) of the evaporation column 140 is connected to a bottom reflux line 148 and a concentrate discharge line 160. A tank reflux switch valve and a tank reflux regulator valve (collectively, "tank reflux valve 142") are provided on the tank reflux line 148. A bottoms reflux line 148 is used to reflux at least a portion of the distillate to the evaporation column 140 via a bottoms reflux valve 142. The concentrate discharge line 160 is used to allow at least a portion of the concentrate of the evaporation tower 140 to exit the evaporation tower 140. A concentrate discharge regulating valve (not shown in fig. 1) is provided on the concentrate discharge line 160.
With respect to a compressor (not shown in fig. 1), it communicates with the top end of the evaporation tower 140 for compressing the secondary steam outputted from the evaporation tower 140 so as to raise the temperature and pressure of the secondary steam. The compressed secondary steam is sent to the reboiler 130 shell side to heat the spent liquor.
With respect to reboiler 130, it is used to provide heat to the bottom of evaporation column 140.
With respect to the control device 110, it comprises, for example, at least one processing unit and at least one memory, the at least one memory being coupled to the at least one processing unit and storing instructions for execution by the at least one processing unit, when the instructions are executed by the at least one processing unit, to control the heat pump evaporation apparatus 120. The control device 110, which may have one or more processing units, includes special purpose processing units such as GPUs, FPGAs, ASICs, and the like, as well as general purpose processing units such as CPUs. In addition, one or more virtual machines may also be running on each control device 110. In some embodiments, the control device 110 is, for example, a PLC for controlling the heat pump evaporation apparatus 120, which may be used in three modes of operation, "automatic operation," semi-automatic operation, "and" manual operation. In some embodiments, the control device further comprises a communication system for transmission of the accumulated flow value and the electrical energy via a communication protocol, etc.
A method for controlling a tank level of a waste liquid heat pump evaporation system according to an embodiment of the present disclosure will be described below with reference to fig. 1 to 3. Fig. 2 illustrates a flow chart of a method 200 for controlling a column bottoms level of a waste heat pump evaporation system, in accordance with an embodiment of the present disclosure. Fig. 3 shows a schematic diagram of a waste liquid heat pump evaporation system 300 according to an embodiment of the disclosure. It should be appreciated that the method 200 may be performed, for example, at the electronic device 600 depicted in fig. 6. But may also be performed at the control device 110 depicted in fig. 1. It should be understood that method 200 may also include additional acts not shown and/or may omit acts shown, the scope of the present disclosure being not limited in this respect.
At step 202, the control device 110 obtains a current level and concentration of a waste liquid at a bottom of the evaporation tower, a flow rate of secondary steam output from a top of the evaporation tower, and a waste liquid feeding flow rate. The evaporation tower is comprised by the waste liquid heat pump evaporation system, the waste liquid heat pump evaporation system at least comprises a waste liquid tank, a reboiler and a control device, waste liquid in the waste liquid tank is sent to the evaporation tower and the reboiler after passing through a feeding pump and a waste liquid preheater (e.g. a primary preheater and a condensed gas cooler), at least part of distilled liquid is refluxed to the evaporation tower through a tower kettle reflux valve, and concentrated liquid of the evaporation tower is discharged out of the evaporation tower through a concentrated liquid discharge valve.
Method 200 is, for example, operating at steady state operation of waste heat pump evaporation system 300, or normal production conditions. For example, taking fig. 3 as an example, the waste heat pump evaporation system 300 goes through the processes of feeding, preheating and total reflux, and then enters the normal production conditions of distillate and concentrate. The following is an example of the loading, warm-up, and total reflux process of the waste heat pump evaporation system 300 in conjunction with fig. 3. It should be appreciated that the loading, warm-up, full-back process of the waste heat pump evaporation system 300 is not limited to the following exemplary process.
Regarding the loading process, for example, the control device 110 first initializes data, resets all valves; setting and checking initial set values of all process parameters; monitoring the meter air supply pressure and the liquid level of the electric heater 360; then, based on the concentration of the waste liquid to be treated and the amount of the waste liquid, the production discharge amount and the evaporation concentration times are calculated for the set values of the subsequent control. Thereafter, the control device 110 activates the feed pump 304, opens the feed switch valve 306 and the feed regulator valve 308 for feeding the evaporation tower 330 until it is determined that the liquid level of the evaporation tower 330 reaches a first predetermined liquid level threshold (e.g., a predetermined high liquid level set point) or that the difference from the predetermined first liquid level is within a first predetermined range. The first predetermined range is, for example, an error allowed by the target liquid level.
Regarding the warm-up procedure, it includes, for example: if the control device 110 determines that the liquid level of the evaporation tower 330 reaches a first predetermined liquid level threshold (e.g., a predetermined high liquid level set point), the feeding is stopped. The heating steam on-off valve 344 and the heating steam adjusting valve 346 are opened to feed steam into the reboiler 342 to start heating the waste liquid. When the waste liquid temperature reaches the set temperature, the heating steam on-off valve 344 and the heating steam adjusting valve 346 are closed, and the heating is stopped. Thereafter, the control apparatus 110 activates the distillate pump 364, and opens the desuperheating water switching valve 326 and the desuperheating water regulating valve 328 to introduce a flow of desuperheating water into the inlet of the compressor 350 to eliminate the degree of superheat during operation of the compressor. 362 is a desalination water valve. The control device 110 turns on the fan, water pump, and chilled water system of the compressor 350, starts the compressor system such that the compressor 350 is first operated at a predetermined first frequency (e.g., without limitation, 25 Hz), for example, and then gradually turns off the compressor self-circulation regulating valve 354, during which the control device 110 may determine whether the outlet pressure, inlet-outlet pressure differential, of the compressor 350 is less than or equal to a predetermined safety pressure threshold; if it is less than or equal to the predetermined safety pressure threshold value, the compressor self-circulation regulating valve 354 is continuously closed, if it is greater than the predetermined safety pressure threshold value, the compressor self-circulation regulating valve 354 is maintained at the current opening degree for a predetermined period of time (for example, without limitation, 3 to 5 min) or the opening degree of the compressor self-circulation regulating valve 354 is increased, and if it is determined that the self-circulation regulating valve 354 of the compressor 350 is completely closed, the frequency of the compressor 350 is increased to a predetermined frequency set value (for example, without limitation, 55 Hz). 352 is the compressor self-circulation on-off valve. By adopting the means described above, it is advantageous to ensure safe operation of the compressor 350.
Regarding the total reflux process, it includes, for example: the control device 110 determines whether the pressure of the vaporization tower 330 is below a predetermined pressure set point (e.g., without limitation, 60 kPa); if it is determined that the pressure is lower than the predetermined pressure set value, the heating steam switching valve 344 is opened, and the opening degree of the heating steam adjusting valve 346 is controlled so as to supplement heat to the heat pump evaporation device to increase the pressure of the evaporation tower 330. Then, the control device 110 opens the distillation liquid column bottom reflux switch valve 316 and the column bottom reflux regulating valve 318, and enters the total reflux working condition of the waste liquid heat pump evaporation system 300. With respect to normal production conditions, control device 110 determines whether the conductivity of the distillate is below a predetermined conductivity threshold; if the control device 110 determines that the conductivity of the distillate is below a predetermined conductivity threshold (e.g., without limitation, 1 μs/cm), the feed pump 304 is again activated for feeding the evaporation column 330 into normal production conditions of the heat pump evaporation system 300.
In normal production conditions, the distillate and concentrate are, for example, continuously discharged for production at the same time. Specifically, the control device 110 starts the feeding pump 304, opens the feeding switch valve 306 and the feeding adjustment valve 308, feeds the evaporation tower 330, simultaneously opens the distillate discharge switch valve 314 and the distillate discharge adjustment valve 312, and closes the tower kettle reflux switch valve 316, so that qualified distillate is discharged for production. When the waste liquid in the evaporation tower 330 is evaporated and concentrated to a set concentration or the density reaches a set value, a concentrated solution discharge valve 332 is opened, and a distillation liquid tower kettle reflux switch valve 316 and a distillation liquid tower kettle reflux regulating valve 318 are opened.
As shown in fig. 1, the control device 110 obtains the waste liquid feeding flow rate via the first flow meter 152; acquiring the flow rate of the secondary steam output from the top of the evaporation tower through a second flowmeter 154; the level of the bottoms liquid is obtained via the first level gauge 150.
At step 204, control device 110 obtains a bottoms reflux stream of the distillate and a discharge of the concentrate.
For example, control device 110 obtains a bottoms reflux stream of the distillate via fourth flow meter 146; and the discharge amount of the concentrate is acquired via the fifth flowmeter 122.
At step 206, control device 110 controls at least one of a concentrate discharge valve and a bottoms reflux valve such that a bottoms reflux flow of the distillate matches a discharge of the concentrate. For example, control device 110 automatically adjusts the concentrate discharge valve (e.g., 332 in FIG. 3) and the column bottoms reflux valve (e.g., distillate column bottoms reflux regulator valve 318 in FIG. 3) so that the reflux flow of distillate coincides with the concentrate discharge flow to maintain stable operation of the column bottoms level. In some embodiments, control device 110 may fixedly control the opening of the concentrate discharge valve, adjusting only the bottoms reflux valve, so that the difference between the reflux flow of the distillate and the concentrate discharge flow is less than or equal to a predetermined threshold or so that the bottoms reflux flow of the distillate and the concentrate discharge flow match.
With respect to a method for matching a column bottoms reflux flow rate of a distillate with a discharge amount of a concentrate, it includes, for example: determining whether the concentration of the waste liquid in the tower kettle is within a second preset range of a preset concentration set value; and in response to determining that the concentration of the bottoms liquid is within a second predetermined range of the predetermined concentration set point, maintaining the concentrate discharge valve at the current opening; determining whether a difference between a bottoms reflux flow of the distillate and a discharge of the concentrate is greater than a predetermined threshold; in response to determining that the difference between the bottoms reflux flow of the distillate and the discharge of the concentrate is greater than a predetermined threshold, adjusting, via a valve positioner, an opening of a bottoms reflux regulating valve on a bottoms reflux line disposed between a bottoms of the evaporation tower and a top reflux line, based on the difference between the bottoms reflux flow of the distillate and the discharge of the concentrate; and determining that the bottoms reflux flow of the distillate matches the discharge of the concentrate in response to determining that the difference between the bottoms reflux flow of the distillate and the discharge of the concentrate is less than or equal to the predetermined threshold. The method for controlling the concentrate discharge valve and the reflux valve of the column bottom will be further described with reference to fig. 4, and will not be described here.
A method for determining whether the concentration of a bottoms liquid is within a second predetermined range of a predetermined concentration set point, for example, comprising: calculating the density of the waste liquid in the tower kettle based on the current static pressure difference of a certain tower kettle liquid level measured by the blowing type liquid level meter; and determining whether the calculated concentration of the bottoms liquid is within a second predetermined range of the predetermined concentration set point by the liquid density.
At step 208, the control device 110 adjusts the opening of the feeding adjustment valve on the waste liquid feeding line based on the obtained current liquid level of the waste liquid in the tower kettle, the flow rate of the secondary steam, and the waste liquid feeding flow rate, so that the difference between the current liquid level of the waste liquid in the tower kettle and the predetermined first liquid level is within the first predetermined range, and the waste liquid feeding line is disposed between the feeding pump and the waste liquid preheater. For example, the waste stream feed line is disposed between the feed pump and the primary preheater of the waste stream preheater.
As to a method of determining the opening degree of a feeding regulating valve on a waste liquid feeding line, it includes, for example: the control device 110 determines whether a difference between a current level of the waste liquid at the bottom of the evaporation tower and a predetermined first level is within a first predetermined range, the current level of the waste liquid at the bottom of the tower being measured via a blowing level gauge; if the control device 110 determines that the difference between the current liquid level of the waste liquid at the tower bottom of the evaporation tower and the preset first liquid level is not within the first preset range, determining the opening of the feeding regulating valve 132 through PID calculation based on the acquired current liquid level of the waste liquid at the tower bottom, the flow rate of the secondary steam and the feeding flow rate of the waste liquid; and adjusting a valve positioner 138 of the feed regulating valve based on the determined opening of the feed regulating valve 132 so that a difference between the current level of the column bottoms liquid and the predetermined first level is within a first predetermined range. Specifically, as shown in fig. 1, a main loop is formed by feeding back a liquid level signal of the waste liquid in the tower kettle by the first liquid level meter 150, a feedforward control channel is formed by feeding back a flow signal of the secondary steam output by the tower top of the evaporation tower by the second flow meter 154, and a secondary loop is formed by feeding back a feeding flow of the waste liquid by the first flow meter 152 so as to timely reflect an adjusting effect and rapidly eliminate spontaneous disturbance of the feeding flow. The primary and secondary regulators are used in series so that the level setpoint 164 of the evaporator column 140 is maintained at steady state. The coupling of the current liquid level signal of the waste liquid at the tower kettle, the flow signal of the secondary steam and the feeding flow signal of the waste liquid and the given value of the liquid level of the evaporation tower are used as control given values of a valve positioner of a feeding regulating valve, and the opening degree of the feeding regulating valve is regulated.
For example, after the system is stably operated, the opening of the feeding adjusting valve 132 is controlled to control the feeding flow rate of the waste liquid during normal operation, so that the feeding flow rate of the waste liquid corresponds to the flow rate of the secondary steam, and the liquid level in the evaporation tower 140 is in a stable state. When the heat source of the system changes suddenly or the flow rate of the secondary steam changes, the evaporation capacity is increased suddenly, namely the flow rate of the secondary steam is increased suddenly. The pressure in the evaporation tower 140 is reduced, the waste liquid in the tower kettle in the evaporation tower 140 is boiled vigorously, and the liquid level rises rapidly, at this time, the false liquid level is easy to cause. Because the present disclosure incorporates a feed-forward disturbance of the flow of the secondary vapor, the control device 110 (e.g., without limitation, a PLC) outputs no increase in the control setpoint signal to the valve positioner 138 of the feed-through regulator valve, and therefore no significant increase in the waste stream feed-through flow. Thus, the present disclosure can avoid the impact of false liquid levels on system control.
In the scheme, the control equipment is used for acquiring the current liquid level and concentration of the waste liquid at the tower bottom of the evaporation tower, the flow of secondary steam output from the top of the evaporation tower, the feeding flow of the waste liquid, the reflux flow of the distillation liquid at the tower bottom and the discharge amount of the concentrated liquid; controlling at least one of a concentrate discharge valve and a tower kettle reflux valve so that the tower kettle reflux flow of the distillate is matched with the discharge amount of the concentrate; the method can effectively ensure conservation of materials of the reflux flow of the tower kettle of the distilled liquid entering the evaporation tower and the discharge amount of the concentrated liquid flowing out of the evaporation tower, so that interference brought by multi-strand feeding and discharging for liquid level control is avoided, and the complexity of liquid level control of the tower kettle is reduced. In addition, this disclosure is through confirming the aperture of the material loading governing valve on the waste liquid material loading pipeline based on the current liquid level of tower cauldron waste liquid, the flow of secondary steam, the waste liquid material loading flow of acquireing to the current liquid level of tower cauldron waste liquid reaches predetermined first liquid level, and this disclosure can realize the accurate and stable control of the tower cauldron waste liquid level of evaporating tower.
A method for matching a bottoms reflux flow of a distillate and a discharge of a concentrate according to an embodiment of the present disclosure will be described below with reference to fig. 3 and 4. FIG. 4 illustrates a flow chart of a method 400 for matching a bottoms reflux flow of distillate and a discharge of concentrate in accordance with an embodiment of the present disclosure. It should be appreciated that the method 400 may be performed, for example, at the electronic device 600 depicted in fig. 6. But may also be performed at the control device 110 depicted in fig. 1. It should be appreciated that method 400 may also include additional actions not shown and/or may omit actions shown, the scope of the present disclosure being not limited in this respect.
At step 402, control device 110 determines whether the concentration of the bottoms liquid is within a second predetermined range of the predetermined concentration set point.
At step 404, if the control device 110 determines that the concentration of the bottoms liquid is within the second predetermined range of the predetermined concentration set point, the concentrate discharge valve 332 is maintained at the current opening. If the control device 110 determines that the concentration of the bottoms liquid is not within the predetermined range of the concentration setpoint, the opening of the concentrate discharge valve 332 is adjusted at step 412. After the concentration and the discharge amount of the waste liquid at the tower kettle reach the set values, the concentrated solution discharge valve is kept at the current opening, so that the concentration of the waste liquid at the tower kettle is not obviously changed in the process of regulating the waste liquid at the tower kettle.
At step 406, control device 110 determines whether the difference between the bottoms reflux flow of the distillate and the discharge of the concentrate is greater than a predetermined threshold.
At step 408, if the control device 110 determines that the difference between the bottoms reflux flow of the distillate and the discharge of the concentrate is greater than the predetermined threshold, the opening of the bottoms reflux regulating valve 318 on a bottoms reflux line, which is disposed between the bottoms of the evaporation tower and the overhead reflux line, is regulated via a valve positioner based on the difference between the bottoms reflux flow of the distillate and the discharge of the concentrate.
At step 410, if control device 110 determines that the difference between the bottoms reflux flow of the distillate and the discharge of the concentrate is less than or equal to the predetermined threshold, it is determined that the bottoms reflux flow of the distillate and the discharge of the concentrate match.
In the above-mentioned scheme, through after tower cauldron waste liquid concentration reaches the setting value with the discharge, keep the aperture of concentrate discharge valve, adjust the aperture of tower cauldron reflux control valve based on the difference between the tower cauldron reflux flow of distillate and the discharge of concentrate, this disclosure can make between the reflux flow of distillate and the discharge of concentrate keep the material business turn over conservation on the one hand, avoid the interference of multistrand feeding ejection of compact to evaporation tower cauldron liquid level control, on the other hand is favorable to making in the in-process of tower cauldron waste liquid regulation, can not make the obvious change of tower cauldron waste liquid concentration take place.
A method for controlling a reflux ratio of an evaporation tower according to an embodiment of the present disclosure will be described below with reference to fig. 3 and 5. Fig. 5 shows a flowchart of a method 500 for controlling the reflux ratio of an evaporation tower according to an embodiment of the disclosure. It should be appreciated that the method 500 may be performed, for example, at the electronic device 600 depicted in fig. 6. But may also be performed at the control device 110 depicted in fig. 1. It should be understood that method 500 may also include additional acts not shown and/or may omit acts shown, the scope of the present disclosure being not limited in this respect.
At step 502, the control device 110 determines whether the reflux ratio of the evaporation tower is within a third predetermined range of the reflux ratio set point.
At step 504, if the control device 110 determines that the reflux ratio of the evaporation column is not within the third predetermined range of the reflux ratio set point, the opening of the overhead reflux valve is adjusted to control the flow rate of the overhead reflux distillate such that the reflux ratio is within the third predetermined range of the reflux ratio set point.
At step 506, if the control device 110 determines that the reflux ratio of the evaporation column is not within the predetermined range of the reflux ratio set point, the opening degree of the overhead reflux valve is adjusted.
In the above scheme, through when the reflux ratio reaches the reflux ratio setting value, the aperture of the top of the tower reflux valve is fixed, and then the tower kettle reflux flow is matched with the concentrated solution discharge amount by adjusting the aperture of the tower kettle reflux regulating valve, the stability of the reflux ratio is maintained in the tower kettle liquid level adjusting process.
Fig. 6 schematically illustrates a block diagram of an electronic device (or computing device) 600 suitable for use in implementing embodiments of the present disclosure. The device 600 may be a device for implementing the methods 200, 400, 500 shown in fig. 2, 4 and 5. As shown in fig. 6, the apparatus 600 includes a Central Processing Unit (CPU) 601, which can perform various suitable actions and processes according to computer program instructions stored in a Read Only Memory (ROM) 602 or computer program instructions loaded from a storage unit 608 into a Random Access Memory (RAM) 603. In the RAM603, various programs and data required for the operation of the device 600 may also be stored. The CPU 601, ROM 602, and RAM603 are connected to each other through a bus 604. An input/output (I/O) interface 605 is also connected to bus 604.
Various components in the device 600 are connected to the I/O interface 605, including: an input unit 606, an output unit 607, a storage unit 608, a processing unit 601 performs the various methods and processes described above, e.g. performing the methods 200, 400, 500. For example, in some embodiments, the methods 200, 400, 500 may be implemented as a computer software program stored on a machine readable medium, such as the storage unit 608. In some embodiments, part or all of the computer program may be loaded and/or installed onto the device 600 via the ROM 602 and/or the communication unit 609. One or more of the operations of the methods 200, 400, 500 described above may be performed when a computer program is loaded into RAM603 and executed by CPU 601. Alternatively, in other embodiments, CPU 601 may be configured to perform one or more actions of methods 200, 400, 500 in any other suitable manner (e.g., by means of firmware).
It is further noted that the present disclosure may be methods, apparatus, systems, and/or computer program products. The computer program product may include a computer readable storage medium having computer readable program instructions embodied thereon for performing aspects of the present disclosure.
The computer readable storage medium may be a tangible device that can hold and store instructions for use by an instruction execution device. The computer readable storage medium may be, for example, but not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. More specific examples (a non-exhaustive list) of the computer-readable storage medium would include the following: portable computer disks, hard disks, random Access Memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static Random Access Memory (SRAM), portable compact disk read-only memory (CD-ROM), digital Versatile Disks (DVD), memory sticks, floppy disks, mechanical coding devices, punch cards or in-groove structures such as punch cards or grooves having instructions stored thereon, and any suitable combination of the foregoing. Computer-readable storage media, as used herein, are not to be construed as transitory signals per se, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., optical pulses through fiber optic cables), or electrical signals transmitted through wires.
The computer readable program instructions described herein may be downloaded from a computer readable storage medium to a respective computing/processing device or to an external computer or external storage device over a network, such as the internet, a local area network, a wide area network, and/or a wireless network. The network may include copper transmission cables, fiber optic transmissions, wireless transmissions, routers, firewalls, switches, gateway computers and/or edge servers. The network interface card or network interface in each computing/processing device receives computer readable program instructions from the network and forwards the computer readable program instructions for storage in a computer readable storage medium in the respective computing/processing device.
Computer program instructions for performing the operations of the present disclosure can be assembly instructions, instruction Set Architecture (ISA) instructions, machine-related instructions, microcode, firmware instructions, state setting data, or source or object code written in any combination of one or more programming languages, including an object oriented programming language such as Smalltalk, c++ or the like and conventional procedural programming languages, such as the "C" programming language or similar programming languages. The computer readable program instructions may be executed entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any kind of network, including a Local Area Network (LAN) or a Wide Area Network (WAN), or may be connected to an external computer (for example, through the Internet using an Internet service provider). In some embodiments, aspects of the present disclosure are implemented by personalizing electronic circuitry, such as programmable logic circuitry, field Programmable Gate Arrays (FPGAs), or Programmable Logic Arrays (PLAs), with state information of computer readable program instructions, which can execute the computer readable program instructions.
Various aspects of the present disclosure are described herein with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the disclosure. It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer-readable program instructions.
These computer readable program instructions may be provided to a processor in a voice interaction device, a processing unit of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processing unit of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks. These computer readable program instructions may also be stored in a computer readable storage medium that can direct a computer, programmable data processing apparatus, and/or other devices to function in a particular manner, such that the computer readable medium having the instructions stored therein includes an article of manufacture including instructions which implement the function/act specified in the flowchart and/or block diagram block or blocks.
The computer readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other devices to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer implemented process such that the instructions which execute on the computer, other programmable apparatus or other devices implement the functions/acts specified in the flowchart and/or block diagram block or blocks.
The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of devices, methods and computer program products according to various embodiments of the present disclosure. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of instructions, which comprises one or more executable instructions for implementing the specified logical function(s). In some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.
The foregoing description of the embodiments of the present disclosure has been presented for purposes of illustration and description, and is not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the various embodiments described. The terminology used herein was chosen in order to best explain the principles of the embodiments, the practical application, or the technical improvements in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.
The foregoing is merely an alternative embodiment of the present disclosure, and is not intended to limit the present disclosure, and various modifications and variations may be made to the present disclosure by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc. that fall within the spirit and principles of the present disclosure are intended to be included within the scope of the present disclosure.
Claims (7)
1. A method for controlling a tank liquid level of a waste liquid heat pump evaporation system including at least an evaporation tower, a waste liquid tank, a reboiler, and a control device, wherein waste liquid in the waste liquid tank is sent to the evaporation tower and the reboiler via a feed pump and a waste liquid preheater, at least a part of distillate is refluxed to the evaporation tower via a tank reflux valve, and a part of concentrate of the evaporation tower is discharged from the evaporation tower via a concentrate discharge valve, the method comprising:
At a control device, acquiring the current liquid level and concentration of waste liquid at the tower bottom of the evaporation tower, the flow of secondary steam output from the top of the evaporation tower and the feeding flow of the waste liquid;
obtaining the reflux flow of the tower kettle of the distillate and the discharge of the concentrate;
controlling at least one of a concentrate discharge valve and a tower kettle reflux valve so that the tower kettle reflux flow of the distillate is matched with the discharge amount of the concentrate; and
based on the obtained current liquid level of the waste liquid in the tower kettle, the flow of the secondary steam and the feeding flow of the waste liquid, the opening of a feeding regulating valve on a waste liquid feeding pipeline is regulated so that the difference value between the current liquid level of the waste liquid in the tower kettle and a preset first liquid level is within a first preset range, the waste liquid feeding pipeline is arranged between a feeding pump and a waste liquid preheater,
wherein controlling at least one of the concentrate discharge valve and the column bottoms reflux valve so that the column bottoms reflux flow of the distillate matches the discharge of the concentrate further comprises:
determining whether the concentration of the waste liquid in the tower kettle is within a second preset range of a preset concentration set value;
in response to determining that the concentration of the bottoms liquid is within a second predetermined range of the predetermined concentration set point, maintaining the concentrate discharge valve at a current opening;
Determining whether a difference between a bottoms reflux flow of the distillate and a discharge of the concentrate is greater than a predetermined threshold;
in response to determining that the difference between the bottoms reflux flow of the distillate and the discharge of the concentrate is greater than a predetermined threshold, adjusting, via a valve positioner, an opening of a bottoms reflux regulating valve on a bottoms reflux line disposed between a bottoms of the evaporation tower and a top reflux line, based on the difference between the bottoms reflux flow of the distillate and the discharge of the concentrate; and
in response to determining that the difference between the bottoms reflux flow of the distillate and the discharge of the concentrate is less than or equal to a predetermined threshold, it is determined that the bottoms reflux flow of the distillate and the discharge of the concentrate match.
2. The method of claim 1, wherein determining whether the concentration of the bottoms liquid is within a second predetermined range of the predetermined concentration setpoint comprises:
calculating the density of the waste liquid in the tower kettle based on the current static pressure difference of a certain tower kettle liquid level measured by the blowing type liquid level meter; and
determining whether the calculated concentration of the waste liquid in the tower kettle is within a second preset range of the preset concentration set value through the waste liquid density.
3. The method of claim 1, wherein adjusting the opening of the feed regulator valve on the waste liquid feed line so that the difference between the current level of the tower kettle waste liquid and the predetermined first level is within a first predetermined range comprises:
Determining whether a difference between a current liquid level of the waste liquid at the tower bottom of the evaporation tower and a preset first liquid level is within a first preset range, wherein the current liquid level of the waste liquid at the tower bottom is measured by a blowing type liquid level meter;
determining the opening of a feeding regulating valve through PID calculation based on the obtained current liquid level of the waste liquid of the tower kettle, the flow rate of the secondary steam and the feeding flow rate of the waste liquid in response to determining that the difference between the current liquid level of the waste liquid of the tower kettle of the evaporation tower and the preset first liquid level is not in the first preset range; and
and adjusting a valve positioner of the feeding regulating valve based on the determined opening degree of the feeding regulating valve so that the difference value between the current liquid level of the waste liquid in the tower kettle and the preset first liquid level is within a first preset range.
4. The method of claim 1, further comprising:
determining whether the reflux ratio of the evaporation tower is within a third preset range of the reflux ratio set value; and
in response to determining that the reflux ratio of the evaporation column is not within the third predetermined range of the reflux ratio set point, the opening of the overhead reflux valve is adjusted to control the flow rate of the overhead reflux distillate such that the reflux ratio is within the third predetermined range of the reflux ratio set point.
5. A waste heat pump evaporation system comprising:
The waste liquid tank is used for storing waste liquid, and the waste liquid in the waste liquid tank is sent to the evaporation tower and the reboiler through the feeding regulating valve and the waste liquid preheater;
the evaporation tower is used for performing evaporation operation on the waste liquid in the evaporation tower so as to generate secondary steam and concentrated solution;
a concentrate discharge valve disposed on the concentrate discharge line for allowing the generated concentrate to be discharged out of the evaporation tower via the concentrate discharge valve;
a column bottom reflux valve arranged on the column bottom reflux line for allowing at least part of the distillate to reflux to the evaporation column via the column bottom reflux valve, the concentrate discharge line and the column bottom reflux line being in communication with the bottom of the evaporation column;
a reboiler for providing heat to the bottom of the evaporation tower; and
a control device comprising at least one processing unit and at least one memory coupled to the at least one processing unit and storing instructions for execution by the at least one processing unit, which when executed by the at least one processing unit, cause the control device to perform the method according to any one of claims 1 to 4.
6. A control apparatus comprising:
at least one processing unit;
At least one memory coupled to the at least one processing unit and storing instructions for execution by the at least one processing unit, which when executed by the at least one processing unit, cause the control device to perform the method of any one of claims 1 to 4.
7. A computer readable storage medium having stored thereon machine executable instructions which when executed cause a machine to perform the method of any of claims 1 to 4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111307124.0A CN114014395B (en) | 2021-11-05 | 2021-11-05 | Liquid waste heat pump evaporation system and liquid level control method, control equipment and medium thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111307124.0A CN114014395B (en) | 2021-11-05 | 2021-11-05 | Liquid waste heat pump evaporation system and liquid level control method, control equipment and medium thereof |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN114014395A CN114014395A (en) | 2022-02-08 |
| CN114014395B true CN114014395B (en) | 2024-03-29 |
Family
ID=80061648
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202111307124.0A Active CN114014395B (en) | 2021-11-05 | 2021-11-05 | Liquid waste heat pump evaporation system and liquid level control method, control equipment and medium thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114014395B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN115400444B (en) * | 2022-08-05 | 2024-02-27 | 万华化学（宁波）有限公司 | Rectifying tower control method, storage medium and electronic equipment |
Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| LU49392A1 (en) * | 1964-08-28 | 1965-10-25 | ||
| US4025397A (en) * | 1975-11-28 | 1977-05-24 | Uop Inc. | Method and system for fractionation control responsive to heat balance |
| CN101670184A (en) * | 2009-10-13 | 2010-03-17 | 北京和隆优化控制技术有限公司 | Coordination optimizing control system of multiple targets, such as output, quality, energy consumption of evaporation device |
| CN106348368A (en) * | 2015-07-16 | 2017-01-25 | 中广核工程有限公司 | Heat pump evaporation system and heat pump evaporation method used for processing low-activity liquid waste in nuclear plant |
| CN107930170A (en) * | 2017-11-22 | 2018-04-20 | 江苏迈克化工机械有限公司 | A kind of frequency-converting control device suitable for spent liquor evaporation |
| CN108525338A (en) * | 2017-03-03 | 2018-09-14 | 江西中医药大学 | Alcohol recycle rectifying device and alcohol recycle rectificating method |
| CN108543322A (en) * | 2018-06-20 | 2018-09-18 | 核工业理化工程研究院 | A kind of level controling mechanism and its control method of evaporator with external heating unit |
| CN112107876A (en) * | 2020-09-27 | 2020-12-22 | 江苏科技大学 | Ethylene glycol rich solution regeneration dehydration system and method in deep sea natural gas exploitation process |
| CN112542260A (en) * | 2020-11-05 | 2021-03-23 | 中国核电工程有限公司 | Negative pressure heat pump evaporation treatment system for radioactive waste liquid |
| CN112881594A (en) * | 2020-11-17 | 2021-06-01 | 中国核电工程有限公司 | Performance verification method of nuclear power plant waste liquid treatment device |
| CN112933637A (en) * | 2020-12-28 | 2021-06-11 | 苏州吴淞江制药有限公司 | Control method for ethanol rectification process in automation of traditional Chinese medicine |
| CN113181678A (en) * | 2021-04-13 | 2021-07-30 | 浙江毅聚新材料有限公司 | Automatic control system, method and device for separating and recycling white oil and dichloromethane mixed solution |
| CN113568441A (en) * | 2021-08-27 | 2021-10-29 | 中国核动力研究设计院 | Liquid level control system and method for radioactive waste liquid evaporator |
-
2021
- 2021-11-05 CN CN202111307124.0A patent/CN114014395B/en active Active
Patent Citations (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| LU49392A1 (en) * | 1964-08-28 | 1965-10-25 | ||
| US4025397A (en) * | 1975-11-28 | 1977-05-24 | Uop Inc. | Method and system for fractionation control responsive to heat balance |
| CN101670184A (en) * | 2009-10-13 | 2010-03-17 | 北京和隆优化控制技术有限公司 | Coordination optimizing control system of multiple targets, such as output, quality, energy consumption of evaporation device |
| CN106348368A (en) * | 2015-07-16 | 2017-01-25 | 中广核工程有限公司 | Heat pump evaporation system and heat pump evaporation method used for processing low-activity liquid waste in nuclear plant |
| CN108525338A (en) * | 2017-03-03 | 2018-09-14 | 江西中医药大学 | Alcohol recycle rectifying device and alcohol recycle rectificating method |
| CN107930170A (en) * | 2017-11-22 | 2018-04-20 | 江苏迈克化工机械有限公司 | A kind of frequency-converting control device suitable for spent liquor evaporation |
| CN108543322A (en) * | 2018-06-20 | 2018-09-18 | 核工业理化工程研究院 | A kind of level controling mechanism and its control method of evaporator with external heating unit |
| CN112107876A (en) * | 2020-09-27 | 2020-12-22 | 江苏科技大学 | Ethylene glycol rich solution regeneration dehydration system and method in deep sea natural gas exploitation process |
| CN112542260A (en) * | 2020-11-05 | 2021-03-23 | 中国核电工程有限公司 | Negative pressure heat pump evaporation treatment system for radioactive waste liquid |
| CN112881594A (en) * | 2020-11-17 | 2021-06-01 | 中国核电工程有限公司 | Performance verification method of nuclear power plant waste liquid treatment device |
| CN112933637A (en) * | 2020-12-28 | 2021-06-11 | 苏州吴淞江制药有限公司 | Control method for ethanol rectification process in automation of traditional Chinese medicine |
| CN113181678A (en) * | 2021-04-13 | 2021-07-30 | 浙江毅聚新材料有限公司 | Automatic control system, method and device for separating and recycling white oil and dichloromethane mixed solution |
| CN113568441A (en) * | 2021-08-27 | 2021-10-29 | 中国核动力研究设计院 | Liquid level control system and method for radioactive waste liquid evaporator |
Also Published As
| Publication number | Publication date |
|---|---|
| CN114014395A (en) | 2022-02-08 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US10208964B2 (en) | Steam cooking oven and method | |
| CN114014395B (en) | Liquid waste heat pump evaporation system and liquid level control method, control equipment and medium thereof | |
| CN107885259B (en) | Chlorination reaction temperature control method, system and equipment | |
| JP2002523821A (en) | Controller for determining optimal tuning parameters used in a process control system and method of operating the controller | |
| WO2022091687A1 (en) | Space cleaning device and space cleaning system using same | |
| JP7481123B2 (en) | Vaporization device, film formation device, program for concentration control mechanism, and concentration control method | |
| CN105388765A (en) | Multivariable deduction, predication and control method for middle-speed coal pulverizer | |
| CN109405265A (en) | Fire electric heater | |
| CN106843337A (en) | Intensification humidification control system and its control method of constant temperature humidity chamber | |
| US9208905B2 (en) | Auxiliary feedwater valve control apparatus of steam generator | |
| CN107131651B (en) | Device and method for stably adjusting water temperature | |
| CN114111042A (en) | Direct-heating type sewage source heat pump rapid constant hot water outlet device and control method | |
| EP2798965B1 (en) | Method for humidifying starting tobacco material | |
| EP2492603A2 (en) | Humidity Generator | |
| CN114014396A (en) | Waste liquid heat pump evaporation system and temperature control method, control equipment and medium thereof | |
| CN114014394A (en) | Waste liquid heat pump evaporation system and control method, control equipment and medium thereof | |
| CN114711627B (en) | Instant heating water dispenser, water outlet temperature control method and device thereof and storage medium | |
| US20240123106A1 (en) | Space cleaning device | |
| CN108543322A (en) | A kind of level controling mechanism and its control method of evaporator with external heating unit | |
| CN114014398A (en) | Method, apparatus and medium for controlling evaporation of waste liquid heat pump | |
| JP2021081174A (en) | Vacuum cooling device | |
| JPH06236201A (en) | Control method for process | |
| RU2492145C2 (en) | Method for thermal deaeration of water and apparatus for realising said method | |
| Alsaleem et al. | Adaptive-model predictive control of electronic expansion valves for evaporator superheat minimization | |
| US20130255484A1 (en) | System and method for control of a stripper tower |
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 |