CN111111239A

CN111111239A - Energy-saving heat pump evaporation concentration automatic control system

Info

Publication number: CN111111239A
Application number: CN202010041799.4A
Authority: CN
Inventors: 谈卫军
Original assignee: Shanghai Mingjie Machinery Co ltd
Current assignee: Shanghai Mingjie Machinery Co ltd
Priority date: 2020-01-15
Filing date: 2020-01-15
Publication date: 2020-05-08

Abstract

The invention discloses an energy-saving heat pump evaporation concentration automatic control system, which comprises an evaporation concentration chamber, a heat pump unit and a control system, wherein the heat pump unit comprises an evaporator, a condenser, a compressor, a main throttle valve and an economizer; a feed back port of the evaporation concentration chamber is connected with a cold material inlet of the condenser; the steam port of the evaporation concentration chamber is connected with the evaporator; the hot material outlet of condenser is equipped with temperature sensor, is equipped with temperature sensor and pressure sensor in the evaporative concentration room, is equipped with temperature sensor on the compressor, and each temperature sensor and pressure sensor all communicate with control system's PLC controller, and the PLC controller communicates with loading valve, uninstallation valve, cooling valve, vacuum control valve respectively. Adopt above-mentioned structure, its beneficial effect is: the evaporation concentration chamber is matched with the heat pump unit more closely, the control is more accurate, and the maintenance is convenient.

Description

Energy-saving heat pump evaporation concentration automatic control system

Technical Field

The invention belongs to the technical field of evaporation concentration systems, and particularly relates to an automatic control system for evaporation concentration of an energy-saving heat pump.

Background

At present, the evaporation concentration system of the energy-saving heat pump is still in a starting stage, the functions and the coordination of the system are not perfect enough, some systems are semi-automatically controlled, and some systems are basically operated manually by manual judgment, so that great inconvenience is brought to operators.

In addition, the existing heat pump evaporation concentration system comprises a heat pump system and an evaporation concentration system, and the two systems are not integrated together to be controlled at present, are independent and are troublesome to operate. This is because the existing heat pump system and the evaporation concentration system respectively comprise an independent control system, namely a PLC controller and a control panel are respectively set. Some of them are manufactured by two different manufacturers and then assembled together, which brings disadvantages to the upgrading and improvement of the operation and control system. For example, the existing heat pump evaporation and concentration system mainly needs to complete evaporation and concentration of raw materials, the heat pump is an auxiliary device which provides energy and generates heat, but the concentration process is various, the working conditions of the heat pump are also various, the working conditions of the heat pump can be matched with the working conditions of the heat pump, the system is designed differently, and control software is adjusted to better enable the system to run stably. Therefore, the control method of the conventional heat pump evaporation and concentration system may have a risk of communication information error, and the two systems are independent from each other and are troublesome to maintain. Moreover, the existing heat pump evaporation concentration system is almost semi-automatically controlled, needs a plurality of persons to intervene in the whole process, and has high labor cost.

In addition, in the existing heat pump evaporation concentration system, an evaporation concentration chamber needs to be connected with a steam-water heat exchanger firstly, and cooling water is used for cooling material steam and then is connected with an evaporator. The existing evaporation concentration system mainly has the following problems:

1. when the steam-water heat exchanger is used, cooling water needs to be continuously introduced into the steam-water heat exchanger, a large amount of water resources are wasted, and the energy of steam is not reasonably utilized, so that the energy is wasted.

2. In a condenser in a heat pump system of an existing evaporation concentration system, solutions to be concentrated, such as traditional Chinese medicine solutions, are led in a tube pass of the condenser, refrigerant gas is led in a shell pass of the condenser, and a gas baffle plate is not arranged at a gas inlet of the condenser, or a simple small plate is arranged to baffle the refrigerant gas. Consequently, in energy-conserving evaporation heat pump set, can lead to the gas distribution uneven, heat exchanger efficiency is poor to can lead to the partial pipeline at middle part to be directly washed by gas, the heat exchange tube is heated unevenly, leads to intraductal material solution overheated production burnt paste, has reduced heat exchange efficiency and has increased the washing degree of difficulty, in case wash not thoroughly will pollute next batch of material.

3. In an evaporator in a heat pump system of an existing evaporation concentration system, a first liquid inlet of the evaporator is connected with a high-temperature liquid outlet of a steam-water heat exchanger, a second liquid inlet of the evaporator is connected with a throttle valve, and a low-temperature and low-pressure gas-liquid mixture at the outlet end of the throttle valve enters the evaporator to generate refrigerant gas. In the process that the gas-liquid mixture enters the baffle plate of the evaporator, the gas-liquid distribution is uneven, so that the upper layer is gas, the lower layer is liquid, the heat exchange is uneven, and the heat exchange effect is poor.

4. In the existing evaporation concentration system, when the liquid supply amount of a heat pump system in a refrigeration cycle needs to be large, a large-capacity electronic expansion valve or a double-expansion valve is generally selected for throttling. The double expansion valves are adopted for throttling, the control is complex, and the two expansion valves are easy to interfere with each other. The electronic expansion valve with large capacity has large liquid supply amount, but the adjustment range is not large, and the control precision is poor. And its cost is high.

5. The conventional heat pump unit needs to provide a stable heat source for the unit, such as rivers, lakes and seas, underground wells, waste hot water and the like, the requirement on the use place is high, and when the conventional heat pump unit is connected with the heat pump unit, a water pump pipeline system is complex and a complex pump set and a pipeline valve system need to be arranged. Furthermore, the use of rivers, lakes, seas, underground wells, waste hot water, etc., for a long time, may cause damage to the local geology.

6. A compressor is arranged in a conventional heat pump unit, refrigerant gas in a low-pressure state is compressed into gas in a high-pressure state through the compressor, and a refrigeration cycle is formed between the refrigerant gas and a condenser and an evaporator in the heat pump unit. During the operation of the compressor, the temperature of the refrigerant oil is continuously increased, so the system is usually provided with cooling water for cooling. At present, the oil cooling process of a compressor generally adopts cooling water to cool, the cooling water is generally connected with a cooling tower, heat is taken away by the cooling water and discharged into air in the cooling process, and the heat energy utilization rate is low.

There is therefore a need for improvement.

Disclosure of Invention

The invention aims to provide an automatic control system for evaporation concentration of an energy-saving heat pump, which aims to solve the problems of independent coordination, poor control precision and inconvenient maintenance of the existing heat pump system and the existing evaporation concentration system.

In order to achieve the purpose, the invention adopts the following technical scheme:

an energy-saving heat pump evaporation concentration automatic control system comprises an evaporation concentration chamber, a heat pump unit and a control system, wherein the control system comprises a PLC (programmable logic controller) and a control panel, the control panel is communicated with the PLC,

the evaporation concentration chamber comprises a steam port, a feed back port, a discharge port and a feed inlet;

a feed inlet of the evaporation concentration chamber is connected with a hot material outlet of a condenser of the heat pump unit and is used for evaporating and concentrating materials input by the heat pump unit; the return port of the evaporation concentration chamber is connected with a cold material inlet of a condenser of the heat pump unit and is used for inputting materials into the condenser of the heat pump unit to be reheated; the steam port of the evaporation concentration chamber is connected with the solvent steam inlet of the evaporator of the heat pump unit and is used for evaporating part or all volatile components in the material to form steam and conveying the steam into the evaporator of the heat pump unit,

a condenser outlet temperature sensor is arranged at a hot material outlet of the condenser and used for detecting the outlet temperature of the condenser, the condenser outlet temperature sensor is communicated with a PLC (programmable logic controller), and the PLC is communicated with a loading valve and an unloading valve of the compressor and used for controlling the loading or unloading of the compressor so as to control the outlet temperature of the condenser of the heat pump unit;

an evaporation concentration chamber temperature sensor is arranged in the evaporation concentration chamber and used for detecting the temperature in the evaporation concentration chamber, the evaporation concentration chamber temperature sensor is communicated with a PLC (programmable logic controller), and the PLC is communicated with a loading valve and an unloading valve of a compressor and used for controlling the loading or unloading of the compressor, so that the outlet temperature of a condenser of a heat pump unit is controlled, and the temperature of the evaporation concentration chamber is ensured to be within a set range;

an evaporation concentration chamber pressure sensor is arranged in the evaporation concentration chamber and used for detecting the pressure in the evaporation concentration chamber, the evaporation concentration chamber pressure sensor is communicated with a PLC (programmable logic controller), and the PLC is communicated with the vacuum regulating valve and used for regulating the opening degree of the vacuum regulating valve; ensuring the vacuum degree of the evaporation concentration chamber to be in a set range;

the heat pump unit comprises an evaporator, a condenser, a compressor, a main throttle valve and an economizer,

the refrigerant gas inlet of the condenser is connected with the gas outlet of the compressor and is used for exchanging heat and condensing high-temperature and high-pressure refrigerant gas into liquid in a high-pressure state;

a refrigerant liquid outlet of the condenser is connected with a liquid inlet of the economizer, and a liquid outlet of the economizer is connected with a liquid inlet of the main throttle valve through a main pipeline and is used for throttling liquid condensed into a high-pressure state into a low-pressure gas-liquid mixture so as to be convenient for evaporation in a subsequent evaporator; the gas-liquid port of the main throttle valve is connected with the evaporator and used for conveying low-pressure liquid into the evaporator to perform heat exchange and evaporation to form refrigerant gas, and the gas outlet of the evaporator is connected with the gas suction port of the compressor and used for returning the refrigerant gas to the compressor for cyclic utilization;

be equipped with compressor temperature sensor on the compressor for detect the temperature of compressor, compressor temperature sensor communicates with the PLC controller, the PLC controller communicates with the cooling valve for the aperture of the cooling valve of control compressor, when compressor high temperature, then open the cooling valve of compressor, cool off the compressor.

According to the invention, the cold material inlet of the condenser is provided with a condenser inlet temperature sensor for detecting the inlet temperature of the condenser, the condenser inlet temperature sensor is communicated with the PLC, and the loading or unloading of the compressor is accurately controlled by matching the data of the condenser inlet temperature sensor, so that the outlet temperature of the condenser of the heat pump unit is controlled.

According to the invention, the main pipeline is provided with a first bypass pipe for bypassing a part of liquid in a high-pressure state, the first bypass pipe is provided with a first throttle valve for throttling the liquid condensed into the high-pressure state into a gas-liquid mixture in a low-pressure state so as to be convenient for vaporizing into refrigerant gas in a low-temperature and low-pressure state in a subsequent economizer, and the first bypass pipe is connected with a gas-liquid port of the economizer and is used for exchanging heat between the gas-liquid mixture in the low-pressure state and the high-temperature and high-pressure refrigerant liquid;

the heat pump unit further comprises an oil cooling device, an oil inlet of the oil cooling device is connected with an oil outlet of the compressor, an oil outlet of the oil cooling device is connected with an oil inlet of the compressor, a hot air outlet of the oil cooling device is connected with an air inlet of the compressor and used for recovering heat and finally releasing materials in a condenser of the heat pump unit, and a cold air inlet of the oil cooling device is connected with an air outlet of the economizer and used for exchanging heat between low-temperature low-pressure refrigerant gas and hot refrigerating oil.

According to the invention, a density sensor is also arranged in the evaporation concentration chamber and used for detecting the density of the material in the evaporation concentration chamber, the density sensor is communicated with a PLC (programmable logic controller), the PLC is communicated with the discharge pump and the discharge valve and used for controlling the starting and stopping of the discharge pump and the opening of the discharge valve, and in the process of concentration operation, when the density value reaches a set value, the discharge control can be carried out;

the evaporation concentration chamber is provided with a liquid level sensor for detecting the liquid level of the evaporation concentration chamber, the liquid level sensor is communicated with the PLC controller for controlling the frequency of the feeding pump and the opening degree of the feeding valve, and the liquid level of the evaporation concentration chamber is ensured within a normal range.

According to the invention, the exhaust temperature sensor is arranged at the exhaust port of the compressor and used for detecting the gas temperature at the gas outlet of the compressor, the exhaust temperature sensor is communicated with the PLC, the PLC is respectively communicated with the alarm and the shutdown button, and when the temperature is too high or too low, the alarm carries out alarm processing and shuts down so as to be convenient for timely observation and maintenance;

the air outlet of the compressor is also provided with an exhaust pressure sensor for detecting the pressure of the air outlet of the compressor, the exhaust pressure sensor is communicated with a PLC (programmable logic controller), the PLC is respectively communicated with an alarm and a stop button, and when the exhaust pressure is too high or too low, the alarm gives an alarm and stops to facilitate timely observation and maintenance;

the air suction port of the compressor is provided with an air suction temperature sensor for detecting the temperature of the air suction port of the compressor, the air suction temperature sensor is communicated with a PLC (programmable logic controller), the PLC is respectively communicated with an alarm and a stop button, and when the temperature is too high or too low, the alarm carries out alarm processing and stops to facilitate timely observation and maintenance;

the air suction port of the compressor is provided with an air suction pressure sensor for detecting the pressure of the air suction port of the compressor, the air suction temperature sensor is communicated with a PLC (programmable logic controller), and the PLC is communicated with the electronic expansion valve and is used for controlling the opening of the electronic expansion valve so as to control the air suction pressure within a set range.

According to the invention, the solvent vapor inlet of the evaporator is provided with an evaporator inlet temperature sensor for detecting the inlet temperature of the solvent vapor of the evaporator, the evaporator inlet temperature sensor is communicated with the PLC, the PLC is respectively communicated with the alarm and the stop button, and when the temperature is too high or too low, the alarm can give an alarm and stop so as to facilitate timely observation and maintenance.

According to the invention, the heat pump unit further comprises an electromagnetic valve, and the electromagnetic valve is connected with the main throttle valve in parallel. And when the liquid supply amount of the main throttle valve meets the requirement of the heat pump system, closing the electromagnetic valve. When the main throttle valve reaches the set opening and the set value does not reach the standard, the solenoid valve opens the bypass to supply liquid. By adopting the structure, the load of the main throttle valve can be reduced, and the main throttle valve can adjust the flow in a relatively small load interval. Therefore, the model selection capacity of the main throttle valve can be reduced, and meanwhile, the liquid supply amount of the system is adjusted more simply and accurately.

According to the invention, the evaporator comprises an evaporator shell, a plurality of first heat exchange tubes are arranged in the evaporator shell, the first heat exchange tubes are parallel to each other and are distributed in a rectangular array, a solvent steam inlet and a solvent condensate outlet are respectively arranged in the middle of the upper part and the lower part of the evaporator shell, a seal head, a refrigerant inlet and a refrigerant outlet are arranged on the side surface of the evaporator shell, a liquid homogenizing plate is arranged in the seal head and used for enabling a gas-liquid mixture to uniformly enter the first heat exchange tubes, so that a good heat exchange effect is ensured, and a plurality of liquid homogenizing holes are formed in the liquid homogenizing plate;

be equipped with first air baffle between the first heat exchange tube on solvent steam air inlet and upper strata to make solvent steam disperse all around after through first air baffle, be full of the evaporimeter casing fast, with the even heat transfer of the refrigerant in the first heat exchange tube, condense to the solvent condensate, flow from the solvent condensate liquid outlet.

According to the invention, the refrigerant inlet and the refrigerant outlet are arranged at the same side of the evaporator shell, and the end enclosure at the side is internally provided with the first baffle plate, so that the end enclosure is divided into a liquid inlet space and a liquid outlet space. The refrigerant inlet is arranged below the refrigerant outlet, so that a good heat exchange effect is ensured. The first heat exchange tube at the lower part is a refrigerant inlet tube, and the first heat exchange tube at the upper part is a refrigerant outlet tube.

According to the invention, the condenser comprises a condenser shell, a plurality of second heat exchange tubes are arranged in the condenser shell, the second heat exchange tubes are parallel to each other and distributed in a rectangular array for circulating the materials to be concentrated, a refrigerant air inlet and a refrigerant liquid outlet are respectively arranged above and below the condenser shell, a cold material inlet and a hot material outlet are arranged on the side surface of the condenser shell,

a second air baffle is arranged between the refrigerant air inlet and the second heat exchange tube on the upper layer, so that refrigerant gas is scattered to the periphery after passing through the second air baffle and is uniformly filled in the condenser shell, and the phenomenon that part of the second heat exchange tube is overheated is avoided, so that the material is prevented from being burnt, and the material solution after heat exchange of the condenser flows out of the hot material outlet;

the second gas baffle is provided with a plurality of vent holes, the refrigerant gas inlet is arranged right above the middle part of the second gas baffle, and the middle part of the second gas baffle is not provided with vent holes, so that the refrigerant gas is prevented from directly impacting the second heat exchange tube.

According to the invention, the flow area of the vent holes on the second gas baffle is gradually increased from the middle part to the two ends of the second gas baffle, so that the refrigerant gas is ensured to be fully contacted with all the second heat exchange tubes, better heat exchange is realized, and overheating of part of the heat exchange tubes is avoided.

According to the invention, the economizer is a plate heat exchanger.

According to the invention, the automatic control system for evaporation concentration of the energy-saving heat pump further comprises a preheater, a feed inlet of the preheater is connected with a feed tank and used for heating materials, and a feed pipe is arranged between the preheater and the feed tank;

a cold material inlet of a condenser of the heat pump unit is connected with a discharge hole of the preheater through a material conveying pipe and is used for conveying the preheated material into the evaporation concentration chamber or reheating the preheated material input by the preheater and conveying the reheated material into the evaporation concentration chamber;

and the return port of the evaporation concentration chamber is connected with a cold material inlet of a condenser of the heat pump unit and used for inputting materials into the condenser of the heat pump unit to be reheated.

According to the invention, the feed back port of the evaporation concentration chamber is connected with the cold material inlet of the condenser of the heat pump unit through the feed back pipe, and the feed back pipe is provided with the circulating pump for inputting the material which is not completely concentrated in the evaporation concentration chamber into the heat pump unit for reheating.

According to the invention, the evaporation concentration system also comprises a secondary condenser, a condensate tank and a vacuum pump, wherein a solvent condensate liquid outlet of an evaporator of the heat pump unit is connected with a liquid inlet of the secondary condenser and is used for sending condensate liquid after heat exchange into the secondary condenser for continuous cooling;

a liquid outlet of the secondary condenser is connected with a condensate tank, and the condensate tank is used for recovering condensate;

the vacuum pump is connected with the condensate tank and used for enabling the system to be at a set negative pressure value and enabling the solvent to be continuously evaporated in the evaporation and concentration chamber.

Furthermore, a liquid outlet pipe is arranged at the liquid outlet end of the condensate tank, a condensate pump is arranged on the liquid outlet pipe, condensate in the condensate tank is pumped out through the condensate pump, the condensate tank is connected with a solvent storage container, and the solvent storage container is used for recovering and storing the solvent pumped out by the condensate pump.

Furthermore, a second bypass pipe is connected between the feed back pipe and the feed pipe and is used for inputting the incompletely concentrated materials of the evaporation concentration chamber into the preheater for reheating.

According to the invention, the feeding pipe is provided with a feeding pump, and materials in the feeding tank are sent to the preheater for preheating through the feeding pump.

According to the invention, the discharge hole of the evaporation concentration chamber is connected with a discharge pipe, and a discharge pump is arranged on the discharge pipe and used for rapidly discharging evaporated and concentrated materials.

Furthermore, a discharge hole of the evaporation concentration chamber is connected with a discharge tank.

According to the invention, the inlet end of the preheater is connected to a second steam source for the input of steam and for the preliminary preheating of the material.

Further, the second steam source is a device capable of evaporating part or all of volatile components in the material to form steam.

According to the invention, the liquid inlet end of the secondary condenser is connected with a cooling water source and is used for inputting cooling water and carrying out secondary condensation on condensate cooled by the heat pump unit.

The invention discloses an automatic control system for evaporation and concentration of an energy-saving heat pump, which has the beneficial effects that:

1. the heat pump unit and the evaporation concentration chamber are controlled by only one master control system and are responsible for data acquisition, operation, control signal output and other functions, so that the heat pump unit and the evaporation concentration chamber are matched more closely, the control is more accurate, and the maintenance is convenient.

2. When the device is used, parameter setting and operation of each control button can be performed through one control panel, so that the device is convenient to control, a PLC (programmable logic controller) and a control panel (such as a touch screen) are saved, and the cost is reduced; meanwhile, full-automatic control, semi-automatic control or manual control can be selected according to requirements, and the control is flexible.

3. And by adopting full-automatic control, the labor can be saved, and the production efficiency is improved.

4. The control panel is provided with a concentration main interface button which can be used for opening a concentration main interface, can visually display the states of an evaporation concentration chamber, a preheater, a heat pump unit, a condensate tank and the like, and is convenient for a client to operate, observe, operate and the like.

5. Refrigerant steam in a lower temperature state generated by the economizer in the heat pump unit in a circulating manner is used for cooling the refrigeration oil of the compressor, so that the heat of the refrigerant in the circulating manner is continuously remained in the heat pump unit while the engine oil is cooled, and the heat utilization rate is high; meanwhile, cooling equipment such as a cooling tower and the like is not required to be additionally provided, a complex pump set and a pipeline valve system are omitted, and the energy-saving and environment-friendly effects are achieved.

6. The vacuum pump is arranged, so that the whole evaporation and concentration process is carried out in a negative pressure state, the evaporation and concentration chamber can carry out evaporation and concentration at a lower temperature, and meanwhile, the loss of nutrient components or active components of heat-sensitive materials can be reduced; in addition, in a negative pressure environment, solvent steam can automatically flow in a heat pump unit under the action of pressure difference, so that a complex pump set and a pipeline valve system are omitted;

7. the heat pump unit recovers heat in steam evaporated from the evaporation concentration chamber and directly heats materials, and replaces the traditional evaporation concentration system to directly provide steam for heating the materials, so that the whole system is more efficient and energy-saving; meanwhile, the secondary condensation of the steam can be realized only by a small condensation heat exchanger and a small amount of cooling water.

8. The heat pump unit has high heating energy efficiency, can achieve 6.0, namely 1kw of power consumption, and can provide 6kw of heat; and the running cost of the whole machine can be reduced to 25 percent of that of the traditional concentration process, and the cost is greatly reduced.

9. The solvent steam in the evaporation concentration chamber is used as a heat source, and the heat is recycled to heat the material and then enters the evaporation concentration chamber, so that the heat is recycled in the whole system, and the energy-saving and environment-friendly effects are achieved; more specifically: the heat in the steam evaporated from the evaporation concentration chamber is applied to the evaporator, so that the refrigeration cycle is realized, the compressor does not need to supplement refrigerant gas in a low-pressure state all the time, and the resources are saved; meanwhile, the material absorbs heat generated after the evaporation concentration chamber exchanges heat with the heat pump unit to heat the material, and the heated material is used in a steam source, so that the utilization rate of heat energy can be greatly improved, the traditional evaporation concentration chamber is replaced to directly heat cold materials, and the whole system is more efficient and energy-saving;

11. the setting of the liquid equalizing plate and the gas baffle plate of the evaporator can improve the heat exchange effect.

12. The setting of the gas baffle of condenser makes refrigerant gas as even as possible scatter around the shell side, can not directly dash the middle part of second heat exchange tube, consequently can avoid the local overheated problem that produces the burnt paste of second heat exchange tube, improves the cleaning efficiency, avoids next batch material to pollute, simultaneously, can improve heat exchange efficiency.

Drawings

Fig. 1 is a schematic structural diagram of an automatic control system for evaporation and concentration of an energy-saving heat pump according to the present invention. In fig. 1, TC is a temperature sensor, PC is a pressure sensor, LC is a liquid level sensor, ρ C is a density sensor, and FIC is a flow sensor.

Fig. 2 is a block diagram of an automatic control system for evaporation and concentration of an energy-saving heat pump according to the present invention.

Fig. 3 is a schematic structural diagram of an evaporator of the heat pump unit of the present invention.

Fig. 4 is a schematic structural diagram of a condenser of the heat pump unit of the present invention.

Fig. 5 is a schematic structural view of a second baffle on the condenser.

Fig. 6 is another schematic structure diagram of the second baffle on the condenser.

Fig. 7 is another schematic structural diagram of the heat pump unit of the present invention.

Wherein the direction of the arrows in the drawings is the direction of flow of the liquid or gas.

Detailed Description

The automatic control system for evaporation and concentration of the energy-saving heat pump of the invention is further described in detail with reference to the accompanying drawings.

Example 1

As shown in fig. 1 and fig. 2, the automatic control system for evaporation and concentration of a heat pump of the present invention comprises a heat pump system and a control system, wherein the heat pump system and the control system comprise a PLC controller and a control panel, the control panel is in communication with the PLC controller, the heat pump system comprises an evaporation and concentration chamber 1 and a heat pump unit 2, and the evaporation and concentration chamber 1 comprises a steam port 11, a material return port 12, a material discharge port 13 and a material feed port 14; the heat pump unit 2 comprises an evaporator 21, a condenser 22, a compressor 23, a main throttle valve 24, an economizer 26 and an oil cooling device 27, wherein refrigerant is injected into the heat pump unit 2, and the compressor 23 is used for compressing refrigerant gas in a low-pressure state into gas in a high-pressure state. The utility model discloses a heat pump set, including evaporative concentration room 1, PLC controller, evaporative concentration room, PLC controller and compressor, be equipped with evaporative concentration room temperature sensor in the evaporative concentration room 1 for detect the indoor temperature of evaporative concentration, in the concentrated operation, need judge the condition of evaporative concentration room 1 according to the value of this temperature, evaporative concentration room temperature sensor communicates with the PLC controller, and the PLC controller communicates with the load valve and the uninstallation valve of compressor, is used for controlling the loading or uninstallation of compressor to the export temperature of the condenser of control heat pump set guarantees that the temperature of evaporative concentration room is in the settlement range. And an evaporation concentration chamber pressure sensor is arranged in the evaporation concentration chamber 1 and used for detecting the pressure in the evaporation concentration chamber. The pressure sensor of the evaporation concentration chamber is communicated with a PLC controller, and the PLC controller is communicated with the vacuum regulating valve 61 and used for regulating the opening degree of the vacuum regulating valve 61. During the concentration operation, the vacuum degree of the evaporation concentration chamber 1 needs to be adjusted according to the value of the pressure, so as to ensure that the vacuum degree of the evaporation concentration chamber 1 is in a set range.

Be equipped with density sensor in the evaporative concentration room 1 for detect the density of the material in the evaporative concentration room 1, density sensor communicates with the PLC controller, the PLC controller communicates with discharge pump 8, bleeder valve 81 for control opening of discharge pump 8 stops and the aperture of bleeder valve 81, concentrated in service, when density value reaches the setting value, then can carry out ejection of compact control.

Be equipped with level sensor on the evaporation concentration room 1 for detect the liquid level of evaporation concentration room 1, level sensor communicates with the PLC controller, and the PLC controller communicates with charge pump 10 and feed valve 101 respectively, is used for controlling the frequency of charge pump 10 and the aperture of feed valve 101. In operation, the level is controlled to be within a normal range. For example, in the concentrating operation, the frequency of the feed pump 10 and the opening degree of the feed valve 101 are controlled according to the difference between the level value and the set value, so as to ensure that the level of the evaporation concentration chamber 1 is controlled within the set value range.

As shown in fig. 1, the evaporation concentration chamber 1 is further provided with a vent valve 100, which plays a role of venting vacuum, and during initial feeding, the vent valve 100 can be opened to facilitate feeding; opening the dump valve 100 also serves to provide a quick discharge when the last batch is discharged.

As shown in fig. 3, an evaporator 21 of an energy-saving heat pump evaporation concentration automatic control system according to the present invention includes an evaporator housing 210, wherein a plurality of first heat exchange tubes 211 are disposed in the evaporator housing 210, the first heat exchange tubes 211 are parallel to each other and are distributed in a rectangular array, a solvent vapor inlet 212 and a solvent condensate outlet 213 are disposed in the middle of the upper portion and the lower portion of the evaporator housing 210, a head 214, a refrigerant inlet 215 and a refrigerant outlet 216 are disposed on the side surface of the evaporator housing 210, and a liquid-homogenizing plate 217 is disposed in the head 214, and is configured to enable a gas-liquid mixture to uniformly enter the first heat exchange tubes 211, so as to ensure a good heat exchange effect.

The refrigerant inlet 215 and the refrigerant outlet 216 are disposed on the same side of the evaporator shell 210, and a first baffle 219 is disposed in the head 214 on the side, so as to divide the head 214 into a liquid inlet space and a liquid outlet space. The refrigerant inlet 215 is arranged below the refrigerant outlet 216, so that a good heat exchange effect is ensured. The lower first heat exchange tube 211 is a refrigerant inlet tube, and the upper first heat exchange tube 211 is a refrigerant outlet tube.

And a liquid-equalizing space is formed among the liquid-equalizing plate 217, the baffle 219 and the inner wall of the seal head 214, and a plurality of liquid-equalizing holes are formed in the liquid-equalizing plate 217.

A first air baffle 218 is disposed directly above the uppermost first heat exchange tube 211, so that the solvent vapor is dispersed around after passing through the first air baffle 218, and is rapidly filled in the evaporator shell 210, and is condensed into solvent condensate after being uniformly heat-exchanged with the refrigerant (i.e., gas-liquid mixture) in the first heat exchange tube 211, and flows out from the solvent condensate outlet 213.

The first air baffle 218 is a flat plate, and the front end and the rear end of the first air baffle 218 are welded on the inner wall of the evaporator shell 210, so that the solvent vapor is uniformly dispersed; gaps are left between the left and right ends of the first air baffle 218 and the evaporator housing 210, and solvent vapor can flow through the gaps.

As shown in fig. 4, the condenser of the automatic control system for evaporation and concentration of an energy-saving heat pump of the present invention comprises a condenser casing 220, wherein a refrigerant inlet 221 and a refrigerant outlet 222 are respectively arranged above and below the condenser casing 220, a head 225, a cold material inlet 223 and a hot material outlet 224 are arranged on a side surface of the condenser casing 220, a plurality of second heat exchange tubes 226 are arranged in the condenser casing 220, and the second heat exchange tubes 226 are parallel to each other and distributed in a rectangular array for circulating a material solution to be concentrated.

A second air baffle 227 is arranged between the refrigerant air inlet 221 and the second heat exchange tube 226 on the upper layer, so that refrigerant gas is scattered to the periphery after passing through the second air baffle 227 and is uniformly filled in the condenser shell 220, the phenomenon that part of the second heat exchange tube 226 is overheated is avoided, the materials are prevented from being burnt, and heated material solution flows out from the hot material outlet 224; as shown in fig. 5 and 6, the second gas baffle 227 is provided with a plurality of vent holes 228, the refrigerant inlet 221 is disposed right above the middle portion of the second gas baffle 227, and the middle portion of the second gas baffle 227 is not provided with vent holes, so as to prevent the refrigerant gas from directly impacting the second heat exchange tube 226.

The flow area of the vent holes in the second baffle 227 is gradually increased from the middle to both ends of the second baffle 227 to ensure that the refrigerant gas is in full contact with all the second heat exchange tubes 226, thereby achieving better heat exchange and avoiding overheating of part of the heat exchange tubes. For example, as shown in fig. 5, when the diameters of the vent holes 228 are uniform, the number of vent holes from the middle to both ends of the second baffle 227 gradually increases. For another example, as shown in fig. 6, when the number of the vent holes from the middle to both ends of the second baffle 227 is the same, the aperture of the vent holes from the middle to both ends of the second baffle 227 gradually increases.

The cold feed inlet 223 and the hot feed outlet 224 are disposed on the same side of the condenser housing 220. The cold material inlet 223 is arranged below the hot material outlet 224, so that a good heat exchange effect is ensured. The lower second heat exchange tube 226 is a cold material inlet tube and the upper second heat exchange tube 226 is a hot material outlet tube.

The second gas baffle 227 is a flat plate, and the front end and the rear end of the second gas baffle 227 are welded on the inner wall of the condenser shell 220. A gap is left between the left and right ends of the second baffle 227 and the condenser case 220, and refrigerant gas can flow therethrough.

As shown in fig. 1, a refrigerant inlet of the condenser 22 is connected to an exhaust port of the compressor 23, and is configured to exchange heat and condense high-temperature and high-pressure refrigerant gas into high-pressure liquid, an exhaust temperature sensor is disposed at the exhaust port of the compressor 23 and is configured to detect a gas temperature at an air outlet of the compressor, the exhaust temperature sensor is in communication with a PLC controller, the PLC controller is in communication with an alarm and a shutdown button, respectively, when the temperature is too high or too low, the alarm performs alarm processing, and is shut down, so as to observe and repair the problem in time;

an exhaust pressure sensor is arranged at an exhaust port of the compressor 23 and used for detecting the pressure of the exhaust port of the compressor, the exhaust pressure sensor is communicated with a PLC (programmable logic controller), the PLC is respectively communicated with an alarm and a stop button, and when the exhaust pressure is too high or too low, the alarm gives an alarm and stops to facilitate timely observation and maintenance;

the compressor 23 is provided with a compressor temperature sensor for detecting the temperature of the compressor 23, the compressor temperature sensor is communicated with the PLC, the PLC is communicated with the cooling valve of the compressor 23 for controlling the opening degree of the cooling valve of the compressor, and when the temperature of the compressor is too high, the cooling valve of the compressor is opened to cool the compressor.

A refrigerant outlet 222 of the condenser 22 is connected with an inlet of the economizer 26, and an outlet of the economizer 26 is connected with an inlet of the main throttle valve 24 through the main pipe 28, for throttling the liquid condensed into a high-pressure state into a gas-liquid mixture in a low-pressure state, so as to facilitate evaporation in the subsequent evaporator 21; the gas-liquid port of the main throttle valve 24 is connected with the evaporator 21 and used for conveying low-pressure liquid into the evaporator 21 for heat exchange and evaporation to form refrigerant gas, the refrigerant outlet of the evaporator 21 is connected with the air suction port of the compressor 23 and used for returning the refrigerant gas to the compressor 23 for cyclic utilization, the air suction port of the compressor 23 is provided with an air suction temperature sensor for detecting the temperature of the air suction port of the compressor, the air suction temperature sensor is communicated with a PLC (programmable logic controller), the PLC is respectively communicated with an alarm and a stop button, and when the temperature is too high or too low, the alarm carries out alarm processing and stops so as to be convenient for timely observation and maintenance; the air suction port of the compressor 23 is provided with an air suction pressure sensor for detecting the pressure of the air suction port of the compressor, the air suction temperature sensor is communicated with a PLC (programmable logic controller), the PLC is communicated with the electronic expansion valve, the air suction superheat degree can be calculated according to the pressure, the opening degree of the electronic expansion valve is controlled according to the superheat degree, and the air suction superheat degree is controlled within a set range.

Be equipped with first bypass pipe 29 on the trunk line 28 for the liquid of the partly high pressure state of bypass, be equipped with first choke valve 20 on the first bypass pipe 29, be used for becoming the liquid throttle of high pressure state of condensation for the gas-liquid mixture of low pressure state, be convenient for vaporize into the refrigerant gas of low temperature low pressure state in the economic ware 26 of epilogue, first bypass pipe 29 is connected with economic ware 26's gas-liquid mouth for carry out the heat transfer with the gas-liquid mixture of low pressure state and high temperature high pressure refrigerant liquid.

An oil inlet of the oil cooling device 27 is connected with an oil outlet of the compressor 23, an oil outlet of the oil cooling device 27 is connected with an oil inlet of the compressor 23, a hot air outlet of the oil cooling device 27 is connected with an air inlet of the compressor 23 and used for recovering heat and finally releasing the heat to materials in the condenser 22 of the heat pump unit 2, and a cold air inlet of the oil cooling device 27 is connected with an air outlet of the economizer 26 and used for exchanging heat between low-temperature low-pressure refrigerant gas and hot refrigeration oil. It should be noted that the economizer 26 of the present embodiment is preferably a plate heat exchanger. The oil cooling device of the present embodiment is preferably an oil cooling heat exchanger.

The feed inlet 14 of the evaporation concentration chamber 1 is connected with a hot material outlet 224 of a condenser 22 of the heat pump unit 2, and is used for carrying out evaporation concentration on materials input by the heat pump unit 2, the hot material outlet 224 of the condenser 22 is provided with a condenser outlet temperature sensor and is used for detecting the outlet temperature of the condenser, the condenser outlet temperature sensor is communicated with a PLC (programmable logic controller) and is used for controlling the loading or unloading of a compressor, so that the outlet temperature of the condenser of the heat pump unit is controlled, for example, the temperature is higher than a set value, the compressor carries out unloading treatment, the temperature is lower than the set value, and the compressor carries out loading treatment.

The steam port 11 of the evaporation concentration chamber 1 is connected with a solvent steam inlet 212 of an evaporator 21 of the heat pump unit 2 and used for evaporating part or all volatile components in materials to form steam and conveying the steam into the evaporator 21 of the heat pump unit 2, the solvent steam inlet 212 of the evaporator 21 is provided with an evaporator inlet temperature sensor which is used for detecting the inlet temperature of the solvent steam of the evaporator 21, the evaporator inlet temperature sensor is communicated with a PLC (programmable logic controller), the PLC is respectively communicated with an alarm and a shutdown button, and when the temperature is too high or too low, the alarm can give an alarm and shut down so as to observe and overhaul in time; the feed back 12 of evaporative concentration room 1 with the cold material of the condenser 22 of heat pump set 2 imports 223 and connects for reheat in the condenser 22 with material input heat pump set 2, the cold material of condenser 22 imports 223 and is equipped with condenser import temperature sensor for detect condenser import temperature, condenser import temperature sensor and PLC controller communicate, cooperate condenser import temperature sensor's data, the loading or the uninstallation of accurate control compressor, thereby the exit temperature of the condenser of control heat pump set.

The evaporation concentration system further comprises a preheater 5, a feed inlet of the preheater 5 is connected with a feed tank (not shown in the figure) and used for heating materials, and a feed pipe 18 is arranged between the preheater 5 and the feed tank.

The cold material inlet 223 of the condenser 22 of the heat pump unit 2 is connected with the discharge hole of the preheater 5 through the material conveying pipe 25, and is used for conveying the preheated material into the evaporation concentration chamber 1, or is used for reheating the preheated material input by the preheater and conveying the reheated material into the evaporation concentration chamber 1.

The evaporation concentration system also comprises a secondary condenser 3 and a condensate tank 4, wherein a solvent condensate liquid outlet of an evaporator 21 of the heat pump unit 2 is connected with a liquid inlet of the secondary condenser 3 and is used for sending condensate liquid after heat exchange into the secondary condenser 3 for continuous cooling; the liquid outlet and the lime set jar 4 of secondary condenser 3 are connected, lime set jar 4 is used for retrieving the condensate, the solvent lime set liquid outlet 213 of evaporimeter 21 is equipped with evaporimeter export temperature sensor for detect the exit temperature of the solvent lime set of evaporimeter, the solvent lime set liquid outlet and the PLC controller of evaporimeter 21 communicate, the PLC controller communicates with alarm and stop button respectively, and too high or low when the temperature, the alarm all can report to the police and handle to shut down, observe and overhaul etc..

The evaporation concentration system also comprises a vacuum pump 6, wherein the vacuum pump 6 is connected with the condensate tank 4 and is used for enabling the system to be at a set negative pressure value and enabling the solvent to be continuously evaporated in the evaporation concentration chamber 1. A liquid outlet pipe 17 is arranged at the liquid outlet end of the condensate tank 4, a condensate pump 9 is arranged on the liquid outlet pipe 17, condensate in the condensate tank 4 is pumped out through the condensate pump 9, the condensate tank 4 is connected with a solvent storage container (not shown in the figure), and the solvent storage container is used for recovering and storing the solvent pumped out by the condensate pump 9.

Be equipped with condensate tank level sensor on the condensate tank 4 for detect the liquid level of condensate tank 4, condensate tank level sensor communicates with the PLC controller, and the PLC controller communicates with condensate pump 9, condensate valve 91 respectively, is used for controlling opening of condensate pump 9 and opening of condensate valve 91. In the concentration operation, the frequency of the condensate pump is controlled according to the liquid level value.

The feed back 12 of evaporation concentration room 1 and the cold material import 223 of heat pump set 2's condenser 21 are connected through feed back pipe 15, be equipped with circulating pump 7 and ooff valve 71 on feed back pipe 15 for with evaporation concentration room 1 not concentrated complete material input heat pump set 2 reheat, circulating pump 7 and ooff valve 71 all communicate with the PLC controller, through the opening of PLC controller control circulating pump 7 open and stop and ooff valve 71.

A second bypass pipe 19 is connected between the feed back pipe 15 and the feed pipe 18, and is used for inputting the incompletely concentrated materials of the evaporation and concentration chamber 1 into the preheater 5 for reheating.

The feeding pipe 18 is provided with a feeding pump 10, and materials in the feeding tank are sent to the preheater 5 through the feeding pump 10 to be preheated.

The discharge hole 13 of the evaporation concentration chamber 1 is connected with a discharge pipe 16, and the discharge pipe 16 is provided with a discharge pump 8 for rapidly discharging the evaporated and concentrated material. The other end of the discharge pipe 16 may be connected to a discharge tank (not shown) for collecting the concentrated material.

The inlet end of the preheater 5 is connected with a second steam source (the second steam source is a device capable of evaporating part or all of volatile components in the material to form steam, for example, a steam outlet of a heating water tank, etc.), and is used for inputting steam and preliminarily preheating the material. Because heat pump set 2 is direct to be connected with evaporative concentration room 1, can carry out circulation heating to the material, consequently the evaporative concentration system of this embodiment only needs very little pre-heater to and this pre-heater only needs a small amount of steam. The inlet end of the preheater 5 is provided with a preheater temperature sensor for detecting the temperature of the outlet of the steam preheating valve, the preheater temperature sensor is communicated with a PLC (programmable logic controller), the PLC is communicated with the preheating valve 51, and the opening of the preheating valve 51 is controlled according to the temperature to control the preheating temperature within a set range.

The liquid inlet end of the secondary condenser 3 is connected with a cooling water source (for example, a liquid inlet of a cooling water tank, a tap water pipe and the like) and used for inputting cooling water and carrying out secondary condensation on the condensate cooled by the heat pump unit 2. Moreover, since the heat pump unit 2 has already cooled the steam in the evaporation concentration chamber 1 once, the evaporation concentration system of the embodiment only needs a small condensing heat exchanger and a small amount of cooling water.

The feed inlet of pre-heater 5 is equipped with feeding flow sensor, and feeding flow sensor communicates with the PLC controller for detect the flow and the accumulative total flow of feeding, be used for the real-time flow of record, accumulative flow, and single accumulative flow, can synthesize contrast with ejection of compact flow, lime set flow, observation device performance.

The discharge gate of evaporative concentration room 1 is equipped with ejection of compact flow sensor, and ejection of compact flow sensor communicates with the PLC controller for detect the flow and the accumulative total flow of the ejection of compact, be used for the real-time flow of record, accumulative flow, and single accumulative flow, can synthesize contrast with feeding flow, lime set flow, the observation device performance.

The discharge gate of condensate pump 9 is equipped with condensate flow sensor, and condensate flow sensor communicates with the PLC controller for detect the flow and the accumulative total flow of condensate, be used for the real-time flow of record, accumulative total to and single accumulative total, can synthesize contrast with feeding flow, ejection of compact flow, observation device performance.

The control panel is also provided with a USB or Bluetooth data interface, and historical data and the like can be transmitted to the terminal equipment through a communication cable.

The control panel is a touch screen, a concentration main interface button is arranged on the touch screen and used for opening a concentration main interface, and the concentration main interface is displayed with flow diagram intentions and state diagrams of an evaporation concentration chamber, a preheater, a heat pump unit, a condensate tank and various switch valves. Can be used for visually displaying the states of an evaporation concentration chamber, a preheater, a heat pump unit, a condensate tank and the like.

A manual control button, a manual start button, a manual stop button, a heat pump state button and the like of the heat pump unit are arranged on the concentration main interface; the concentration main interface is provided with a full-automatic stop button and a full-automatic start button which are respectively used for controlling the full-automatic start or the full-automatic stop of the evaporation concentration system, and the buttons are simple and convenient to operate. Therefore, the setting of the concentration main interface is convenient for the user to operate and observe the running condition.

Example 2

Fig. 7 is another schematic structural diagram of the heat pump unit of the present invention. The heat pump unit 2 includes an evaporator 21, a condenser 22, a compressor 23, a main throttle valve 24, and an electromagnetic valve 26. The structure and connection relationship of the evaporator 21, the condenser 22, the compressor 23, and the main throttle 24 are the same as those in embodiment 1. The difference is that the solenoid valve 26 of the heat pump unit 2 is arranged in parallel with the main throttle valve 24. When the liquid supply amount of the main throttle valve 24 meets the requirements of the heat pump system (namely, indexes such as pressure and temperature meet the requirements), the electromagnetic valve is closed. When the main throttle valve 24 reaches the set opening and the set value does not reach the standard, the electromagnetic valve 26 opens the bypass liquid supply. With this structure, the load of the main throttle 24 can be reduced, so that the main throttle 24 performs flow rate adjustment within a relatively small load interval. Therefore, the model selection capacity of the main throttle valve 24 can be reduced, and meanwhile, the liquid supply amount of the system is adjusted more simply and accurately.

The energy-saving heat pump evaporation concentration automatic control system of the embodiment has a plurality of control modes such as manual control, semi-automatic control and full-automatic control. When the system is complete, the system can run automatically, is started by one key, runs automatically in the middle, and brings great convenience to operators; when the system is not complete, the system can be controlled semi-automatically or manually to meet the debugging and process control requirements of customers to the greatest extent. Each system is described in detail below.

Embodiment 3 Manual control of automatic control system for evaporation and concentration of energy-saving heat pump

All valves and all water pumps in the energy-saving heat pump evaporation concentration automatic control system can be operated manually, the heat pump unit 2 can be independently and manually started or stopped, and all valves and all water pumps in the system are communicated with the PLC. Manual control may be employed in debugging or special process control. Manual control requires skill in process knowledge, and during operation, operating data needs to be observed all the time, and according to data conditions, some operations need to be performed through manual confirmation.

Embodiment 4 semi-automatic control of energy-saving heat pump evaporation concentration automatic control system

The semi-automatic control of the energy-saving heat pump evaporation concentration automatic control system comprises the following steps: feeding control, preheating control, vacuum control, condensate control, discharging control, heat pump control and circulation control. Wherein, the PLC controller is respectively communicated with the feeding control button, the preheating control button, the vacuum control button, the condensing control button, the discharging control button, the heat pump control button and the circulating control button.

(1) The process of feed control is as follows: clicking a feeding control button on a control panel, opening a feeding pump 10, opening a feeding valve 101, opening a feeding valve 52 of a feeding hole of the preheater 5, and opening a feeding valve 141 of a feeding hole of the evaporative concentration chamber 1 to start feeding; meanwhile, the feed flow sensor starts to communicate with the PLC controller; when the feed control stop button on the control panel is clicked, the feed pump 10 is closed, the feed valve 52 of the feed inlet of the preheater 5 is closed, and the feeding is stopped.

(2) The process of the preheating control is as follows: clicking a preheating control button on a control panel, opening a preheating valve 51 of the preheater 5, starting air inlet, and controlling the preheating temperature of the preheater 5; meanwhile, the preheater temperature sensor is communicated with the PLC; clicking the preheating control stop button on the control panel closes the preheating valve 51 of the preheater 5 and stops the air intake.

(3) The process of vacuum control is as follows: clicking a vacuum control button on a control panel, starting a vacuum pump 6, starting a vacuum switch valve 62, starting a liquid inlet valve 41 of a liquid inlet of a condensate tank 4, starting a liquid inlet valve 31 of a liquid inlet of a secondary condenser 3, opening a liquid outlet valve 2130 of a solvent condensate liquid outlet of an evaporator 21 on a heat pump unit 2, and starting a steam valve 110 of a steam port of an evaporation concentration chamber 1; clicking a vacuum control stop button on the control panel, stopping the vacuum pump 6, closing the vacuum switch valve 62, closing the liquid inlet valve 41 of the liquid inlet of the condensate tank 4, closing the liquid inlet valve 31 of the liquid inlet of the secondary condenser 3, closing the liquid outlet valve of the solvent condensate outlet of the evaporator 21 on the heat pump unit 2, and closing the steam valve 110 of the steam outlet of the evaporation concentration chamber 1.

(4) The discharging control process is as follows: clicking a discharging control button on a control panel, starting a discharging pump 8, starting a discharging valve 81 at a discharging port of the evaporation concentration chamber 1, simultaneously communicating a density sensor with a PLC (programmable logic controller), and communicating a discharging flow sensor with the PLC; clicking a discharging control stop button on the control panel, stopping the discharging pump 8, and closing a discharging valve 81 at a discharging port of the evaporation concentration chamber 1.

(5) The heat pump control process is as follows: clicking a heat pump control button on a control panel; the condenser 22, the evaporator 21, the compressor 23, the oil cooling device 27, the main throttle valve 24 and the first throttle valve 20 are opened, and meanwhile, an exhaust temperature sensor, an exhaust pressure sensor, an air suction temperature sensor, an air suction pressure sensor, a compressor temperature sensor, an evaporator inlet temperature sensor, an evaporator outlet temperature sensor, a condenser outlet temperature sensor and a condenser inlet temperature sensor are respectively communicated with the PLC; clicking a heat pump control stop button on a control panel; the condenser 22, the evaporator 21, the compressor 23, the oil cooling device 27, the main throttle valve 24, and the first throttle valve 20 are closed.

(6) The cycle control process is as follows: clicking a circulation control button on a control panel to start the circulation pump 7, and opening the switch valve 71; the materials below the evaporation concentration chamber 1 are sent into the heat pump unit 2 through the circulating pump 7 for heat exchange, and the heat is brought into the evaporation concentration chamber 1 through the circulating pump 7 to enable the materials to be evaporated and concentrated all the time. Clicking the circulation control stop button on the control panel stops the circulation pump 7 and closes the on-off valve 71.

Embodiment 5 full-automatic control of automatic control system of energy-saving heat pump evaporation concentration system

The full-automatic control process of the automatic control system of the energy-saving heat pump evaporation concentration system comprises the following steps:

clicking a button on the control panel to start the button, and completely automatically operating, wherein an operator only needs to pay attention to the material loading and unloading of the material feeding tank and the material discharging tank. Firstly, the feed pump 10 is started, and the frequency of the feed pump 10 and the opening degree of the feed valve 101 are adjusted according to the liquid level in the evaporation concentration chamber 1, so that the liquid level in the evaporation concentration chamber 1 reaches a set value; it should be noted that, when feeding for the first time, because the temperature of the raw material may be too low and lower than the starting condition of the heat pump unit 2, the steam preheating valve 51 of the preheater 5 is opened to preheat the raw material by the steam of the preheater 5 and rapidly raise the temperature, so that the temperature of the raw material in the evaporation concentration chamber 1 rapidly reaches the starting temperature of the heat pump;

when the liquid level in the evaporation concentration chamber 1 reaches the set requirement, starting the circulating pump 7; the materials below the evaporation concentration chamber 1 are sent into the heat pump unit 2 through the circulating pump 7 for heat exchange, and the heat is brought into the evaporation concentration chamber 1 through the circulating pump 7 to enable the materials to be evaporated and concentrated all the time. And/or the material in the material return pipe 15 enters the preheater 5 through the second bypass pipe 19 to be preheated, and then is sent into the heat pump unit 2, and the operation is repeated.

When the preheating temperature and the liquid level in the evaporation concentration chamber 1 reach the set requirements, the vacuum pump 6 and the vacuum switch valve 62 are opened, the system is pumped to negative pressure and reaches the set negative pressure value, and the solvent is continuously evaporated in the evaporation concentration chamber 1. Meanwhile, the pressure sensor of the evaporation concentration chamber adjusts the opening degree of the vacuum regulating valve 61 by detecting the pressure of the evaporation concentration chamber 1, so that the pressure of the evaporation concentration chamber 1 is kept in a set range;

when the pressure of the evaporation concentration chamber 1 reaches the pressure condition of starting the heat pump unit 2, automatically starting the heat pump unit to run, closing the preheating valve 51 of the preheater 5, and starting to use the heat pump unit 2 to supply heat for concentration;

in the operation of the heat pump, the loading or unloading of the compressor 23 is controlled by the outlet temperature of the condenser, the opening degree of an electronic expansion valve of the compressor 23 is controlled by the suction superheat degree, and whether the operation of the heat pump is normal is judged by the exhaust temperature, the suction temperature, the exhaust pressure, the suction pressure and the like;

and then, the evaporated solvent is cooled and condensed after heat is extracted by the heat pump unit 2, and then enters the secondary condenser 3 to be continuously cooled to the rated temperature, and enters the condensate tank 4. Meanwhile, during the automatic concentration operation of the materials in the evaporation concentration chamber 1, the liquid level of the condensate tank 4 is monitored in real time, and the frequency of the condensate pump 9 is controlled; when the liquid level of the condensate tank 4 rises to a set value, the condensate pump 9 is started to pump out the solvent for recycling and storage. Meanwhile, in the automatic concentration operation of the materials in the evaporation concentration chamber 1, the density data of the evaporation concentration chamber 1 is detected in real time, when the density meets the set discharging requirement, a discharging command is given, the heat pump unit 2, other valves and water pumps are stopped, the discharging pump 8 and the discharging valve 81 are opened, the materials are automatically discharged, and the treated materials are collected and stored. And (4) finishing discharging, closing the discharging pump and the discharging valve, returning to the feeding control, and performing the circulation control.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.

Claims

1. An energy-saving heat pump evaporation concentration automatic control system is characterized by comprising an evaporation concentration chamber, a heat pump unit and a control system, wherein the control system comprises a PLC (programmable logic controller) and a control panel, the control panel is communicated with the PLC,

a feed inlet of the evaporation concentration chamber is connected with a hot material outlet of a condenser of the heat pump unit; a feed back port of the evaporation concentration chamber is connected with a cold material inlet of a condenser of the heat pump unit; the steam port of the evaporation concentration chamber is connected with the solvent steam inlet of the evaporator of the heat pump unit;

a condenser outlet temperature sensor is arranged at a hot material outlet of the condenser and used for detecting the outlet temperature of the condenser, the condenser outlet temperature sensor is communicated with a PLC (programmable logic controller), and the PLC is communicated with a loading valve and an unloading valve of the compressor;

an evaporation concentration chamber temperature sensor is arranged in the evaporation concentration chamber and is communicated with the PLC;

an evaporation concentration chamber pressure sensor is arranged in the evaporation concentration chamber, the evaporation concentration chamber pressure sensor is communicated with a PLC (programmable logic controller), and the PLC is communicated with the vacuum regulating valve;

the refrigerant inlet of the condenser is connected with the exhaust port of the compressor;

a refrigerant liquid outlet of the condenser is connected with a liquid inlet of the economizer, and a liquid outlet of the economizer is connected with a liquid inlet of the main throttle valve through a main pipeline; the gas-liquid port of the main throttle valve is connected with the evaporator, and the gas outlet of the evaporator is connected with the gas suction port of the compressor;

the compressor is provided with a compressor temperature sensor, the compressor temperature sensor is communicated with a PLC controller, and the PLC controller is communicated with a cooling valve of the compressor.

2. The automatic control system for evaporative concentration of an energy saving heat pump according to claim 1, wherein the cold material inlet of the condenser is provided with a condenser inlet temperature sensor, and the condenser inlet temperature sensor is in communication with the PLC controller.

3. The automatic control system for evaporation and concentration of an energy-saving heat pump according to claim 1, wherein a first bypass pipe is arranged on the main pipe, a first throttle valve is arranged on the first bypass pipe, and the first bypass pipe is connected with a gas-liquid port of an economizer;

the heat pump unit further comprises an oil cooling device, an oil inlet of the oil cooling device is connected with an oil outlet of the compressor, an oil outlet of the oil cooling device is connected with an oil inlet of the compressor, a hot air outlet of the oil cooling device is connected with an air inlet of the compressor, and a cold air inlet of the oil cooling device is connected with an air outlet of the economizer.

4. The automatic control system for evaporation concentration of an energy-saving heat pump according to claim 1, wherein a density sensor is further arranged in the evaporation concentration chamber, the density sensor is in communication with a PLC controller, and the PLC controller is in communication with a discharge pump and a discharge valve;

and a liquid level sensor is arranged on the evaporation concentration chamber and is communicated with a PLC (programmable logic controller), and the PLC is respectively communicated with the feeding pump and the feeding valve.

5. The automatic control system for evaporation and concentration of an energy-saving heat pump according to claim 1, wherein an exhaust temperature sensor is arranged at an exhaust port of the compressor, the exhaust temperature sensor is communicated with a PLC (programmable logic controller), and the PLC is respectively communicated with an alarm and a stop button;

an exhaust pressure sensor is further arranged at an exhaust port of the compressor and is communicated with a PLC (programmable logic controller), and the PLC is respectively communicated with an alarm and a stop button;

an air suction port of the compressor is provided with an air suction temperature sensor, the air suction temperature sensor is communicated with a PLC (programmable logic controller), and the PLC is respectively communicated with an alarm and a stop button;

and an air suction port of the compressor is provided with an air suction pressure sensor, the air suction temperature sensor is communicated with a PLC (programmable logic controller), and the PLC is communicated with the electronic expansion valve.

6. The automatic control system for evaporation and concentration of an energy-saving heat pump according to claim 1, wherein the solvent vapor inlet of the evaporator is provided with an evaporator inlet temperature sensor, the evaporator inlet temperature sensor is communicated with a PLC controller, and the PLC controller is respectively communicated with an alarm and a stop button.

7. The automatic control system for evaporation and concentration of an energy-saving heat pump according to claim 1, wherein the heat pump unit further comprises an electromagnetic valve, and the electromagnetic valve is connected in parallel with the main throttle valve.

8. The automatic control system for evaporation concentration of an energy-saving heat pump according to claim 1, further comprising a preheater, wherein a feed inlet of the preheater is connected with a feed tank, and a feed pipe is arranged between the preheater and the feed tank;

a cold material inlet of a condenser of the heat pump unit is connected with a discharge hole of the preheater through a material conveying pipe;

a feed back port of the evaporation concentration chamber is connected with a cold material inlet of a condenser of the heat pump unit;

the discharge hole of the evaporation concentration chamber is connected with a discharge pipe, and a discharge pump is arranged on the discharge pipe and used for rapidly discharging the evaporated and concentrated materials.

9. The automatic control system for evaporation concentration of an energy-saving heat pump according to claim 1, wherein a feed back port of the evaporation concentration chamber is connected with a cold material inlet of a condenser of the heat pump unit through a feed back pipe, and the feed back pipe is provided with a circulating pump.

10. The automatic control system for evaporation concentration of an energy-saving heat pump according to claim 1, wherein the evaporation concentration system further comprises a secondary condenser, a condensate tank and a vacuum pump, and a solvent condensate outlet of an evaporator of the heat pump unit is connected with a liquid inlet of the secondary condenser;

and the vacuum pump is connected with the condensate tank.