Esterification power generation wastewater online monitoring system

Abstract

The utility model relates to the technical field of industrial circulating water monitoring, specifically an online monitoring system for esterification power generation wastewater, including a cooling station for esterification steam power generation, the cooling station is provided with a cooling water pool and a cooling tower, the cooling water pool is provided with a water supply pipe and a wastewater discharge pipe, both the water supply pipe and the wastewater discharge pipe are provided with a control valve, the cooling water pool is also provided with a return pipe and a water supply pipe, the water supply pipe is connected to the water inlet of a condensing device, and the return pipe is connected to the water outlet of the condensing device; the return pipe is provided with an online conductivity detector, the online conductivity detector is electrically connected to the control valve, when the online conductivity detector monitors that the conductivity in the return pipe is greater than a preset value, the control valves on the water supply pipe and the wastewater discharge pipe are controlled to open, and the opening of the control valve on the water supply pipe is greater than or equal to the opening of the control valve on the wastewater discharge pipe. The utility model can solve the problem that the circulating water pool is easily emptied and the cooling water tower trips when the existing method is used to replace cooling water.

Description

Technical Field

[0001] The utility model relates to the technical field of industrial circulating water monitoring, in particular to an esterification power generation wastewater online monitoring system. Background Art

[0002] In the polyester synthesis process, esterification steam of about 103°C will be generated during the esterification stage. This steam carries a large amount of low-grade heat. Taking a 600t / d polyester production device as an example, theoretically, the device will produce about 220t of steam per day, and will release about 5.4*108kJ of latent heat (equivalent to 18.4t of standard coal) during the liquefaction process. Therefore, in order to maximize the use of this waste heat, esterification steam is usually used to generate electricity. For example, our company provides an esterification waste heat power generation system with a publication number of CN217761111U, which includes a power generation device and a condensing device for condensing esterification steam into esterification water. Among them, the cooling circulating water required by the condensing device comes from the esterification power generation cooling station. The cooling station is equipped with a cooling water tower. The cooling water passes into the condensing device and exchanges heat with the esterification water and then returns to the cooling water tower. However, the following technical problems will occur during the circulation process:

[0003] After the cooling water is heat-exchanged, its temperature rises, and it is in contact with the air for a long time in the cooling tower, which is prone to oxidation, resulting in the production of algae and microorganisms in the water and the accumulation of some metal ions, which in turn leads to reduced water purity and deterioration of water quality; if it is not treated, it will affect the cooling and cooling effect of the circulating water, the transportation effect, and even accelerate the scaling and corrosion of the pipeline. In order to ensure the quality of the circulating water and the cooling effect, a part of the water is usually discharged as wastewater, and then some fresh water is added to achieve cooling water replacement; when our company handles the replacement cooling water in the early stage of the transformation, it is usually manually sampling and testing the water quality, and then opening the wastewater discharge pipe for drainage. This method is prone to accidents in actual use, and the control accuracy is not high. It is easy for the circulating water pool to be emptied, causing the cooling tower to jump and the cooling water to be wasted. Based on this, our company has conducted research and improvements on the existing problems. On the basis of not increasing costs, we have realized the water quality monitoring of the cooling station, improved the control accuracy, and reduced the risk of empty towers and jumping towers. Utility Model Content

[0004] The utility model provides an online monitoring system for esterification power generation wastewater, which can solve the problem that the circulating water pool is easily emptied and the cooling water tower is tripped when replacing cooling water in the existing method.

[0005] This application provides the following technical solutions:

[0006] The online monitoring system for esterification power generation wastewater comprises a cooling station for esterification steam power generation, wherein the cooling station is provided with a cooling water pool and a cooling tower, the cooling water pool is provided with a water supply pipe and a wastewater discharge pipe, both the water supply pipe and the wastewater discharge pipe are provided with control valves, the cooling water pool is also provided with a return pipe and a water supply pipe, the water supply pipe is connected to the water inlet of a condensing device, and the return pipe is connected to the water outlet of the condensing device; the return pipe is provided with an online conductivity detector, the online conductivity detector is electrically connected to the control valve, when the online conductivity detector monitors that the conductivity in the return pipe is greater than a preset value, the control valves on the water supply pipe and the wastewater discharge pipe are controlled to be opened, and the opening of the control valve on the water supply pipe is greater than or equal to the opening of the control valve on the wastewater discharge pipe, when the online conductivity detector monitors that the conductivity in the return pipe is less than or equal to the preset value, the control valves on the water supply pipe and the wastewater discharge pipe are controlled to be closed.

[0007] Technical conception: There are multiple water quality indicators for whether the circulating cooling water is replenished and replaced during actual use, including physical indicators, such as water turbidity, color, odor, etc., dissolved salt content indicators, such as salt content, evaporation residue, conductivity, etc., as well as hardness and pH indicators; our company usually takes samples regularly to conduct a full analysis of the water quality in the early stage of the transformation. If the water quality analysis results show that fresh water needs to be added for replacement, the switch valve on the wastewater discharge pipe is manually opened to discharge part of the wastewater; however, this method is not accurately controlled, and usually results in a large amount of wastewater discharge, and even causes the risk of empty towers and tower jumping, and the accident rate is relatively high; in addition, when the wastewater discharge is large, more fresh water needs to be added, which is easy to cause waste of water resources. At the same time, more electricity will be consumed when fresh water is pumped in. Therefore, our company conducted research and technical improvements on the above-mentioned issues. During the improvement process, we found that if a variety of online monitoring instruments are used to conduct comprehensive water quality testing, relevant electrical control equipment must be configured at the same time, which increases the cost of transformation and subsequent use and maintenance costs. Therefore, how to solve the current problems without increasing more transformation costs and electrical control equipment is the main improvement difficulty.

[0008] Beneficial effects:

[0009] 1. Improve control accuracy and control transformation costs through conductivity detection indicators: By setting an online conductivity detector on the return pipe, the state of the circulating water after use can be captured in real time, reflecting its degree of pollution and concentration effect under actual working conditions. This provides favorable data support for evaluating the treatment efficiency of the circulating water system, water quality stability, and whether sewage discharge or adjustment of the treatment plan is required. Compared with setting up multiple online monitoring instruments, it saves transformation costs and maintenance costs, and also achieves the purpose of accurate detection and ensuring the quality of circulating water.

[0010] 2. It can also monitor and warn the cooling equipment: Since the water in the return pipe is the part that returns after circulating inside the cooling equipment, if there are problems such as leakage, corrosion or scaling inside the equipment, it may cause the ion concentration in the circulating water to increase abnormally, thereby affecting the conductivity. Monitoring the conductivity on the return pipe can promptly detect signs of these problems. As an early warning signal, it helps to conduct equipment inspection and maintenance in a timely manner to prevent equipment performance degradation or failure due to water quality problems.

[0011] 3. The water in the water supply pipe has not yet entered the circulation system, and its conductivity may be affected by factors such as fluctuations in the water quality of the source water and changes in the feed water treatment process. Direct monitoring cannot accurately reflect the actual condition of the circulating water during use, and the conductivity in the cooling water tower may be greatly affected by environmental factors (such as rain, dust, spray water evaporation, etc.); therefore, this application sets a conductivity detector on the return pipe, which can focus more on the performance of the circulating water under actual working conditions. The data provided is more targeted, which is conducive to accurate water quality management.

[0012] 4. Liberate manpower and reduce the risk of tower jumping and empty tower: Control the wastewater discharge and water replenishment volume through conductivity data, which is more accurate than manual control of discharge before the transformation. When the conductivity online detector detects that the conductivity in the return pipe is greater than the preset value, the control valves on the water replenishment pipe and the wastewater discharge pipe are controlled to open, and the opening of the control valve on the water replenishment pipe is greater than or equal to the opening of the control valve on the wastewater discharge pipe, avoiding the risk of empty tower and tower jumping; when the conductivity online detector detects that the conductivity in the return pipe is less than or equal to the preset value, the control valves on the water replenishment pipe and the wastewater discharge pipe are controlled to close, saving water resources, reducing wastewater discharge and subsequent treatment volume. At the same time, due to more accurate control, it can also reduce the power consumed by the water delivery pump.

[0013] Furthermore, four groups of circulation pumps are arranged in parallel on the water supply pipe, and the four groups of circulation pumps include two groups of high-power circulation pumps and two groups of low-power circulation pumps.

[0014] Beneficial effect: Setting up two groups of high-power circulation pumps and two groups of low-power circulation pumps is conducive to selective use according to the gas volume of esterification steam to achieve the purpose of energy saving, and at the same time plays the role of one in use and one in reserve to ensure the normal operation of the system.

[0015] Furthermore, a filter is provided at the front end of each circulating pump, and a pressure gauge is provided at the rear end of each circulating pump.

[0016] Beneficial effects: A filter is set at the front end of the circulation pump to filter out foreign particles to prevent the foreign particles from wearing and clogging the circulation pump. A pressure gauge is set at the rear end to detect the use of the circulation pump and the water supply. For example, when the pressure gauge detection value fluctuates, it may indicate that the water quality and quantity fluctuate or the filter at the front end is clogged, so that timely maintenance can be carried out.

[0017] Furthermore, a first pressure-stabilizing tube is provided on the water supply pipe. The first pressure-stabilizing tube is located at the rear end of the four groups of circulation pumps, and a water outlet of the first pressure-stabilizing tube is connected to the cooling water pool.

[0018] Beneficial effect: The first pressure-stabilizing tube is provided to stabilize the pressure of the water supply pipe to avoid pressure build-up. Meanwhile, the water outlet of the first pressure-stabilizing tube is connected to the cooling water tower to realize the self-circulation of cooling water.

[0019] Furthermore, a second pressure-stabilizing tube is arranged between the return pipe and the water supply pipe, and the cooling water in the second pressure-stabilizing tube flows from the return pipe to the water supply pipe.

[0020] Beneficial effects: The second pressure-stabilizing tube is set to balance the pressure fluctuations in the pipeline and add a certain amount of water to the water supply pipe; it can also avoid cavitation of the circulating water pump caused by too low system pressure, and optimize the working state of the circulating water pump by ensuring stable water pressure, thereby reducing system energy consumption; at the same time, the continuous and stable cooling water pressure can reduce the pressure shock to various components in the system (such as pipelines and valves), reduce the risk of fatigue damage and leakage caused by pressure fluctuations, and help extend the service life of the equipment.

[0021] Furthermore, sewage funnels are evenly arranged at the bottom of the cooling water pool, and a drainage pipe is arranged at the bottom of each sewage funnel, and the drainage pipe is connected to the wastewater discharge pipe.

[0022] Beneficial effect: The sewage funnel is provided to facilitate the sedimentation and discharge of the sediment in the cooling water tank, for example, rust particles or impurities are deposited in the sewage funnel and discharged through the wastewater discharge pipe.

[0023] Furthermore, a plurality of overflow pipes are arranged on the top of the cooling water pool, and the drainage port of each overflow pipe is connected to the wastewater discharge pipe.

[0024] Furthermore, the cooling water pool is also provided with a reagent dosing unit, the reagent dosing unit is electrically connected to the control unit, and the reagent dosing unit includes an antiscalant adding unit and an algaecide adding unit.

[0025] Beneficial effects: The scale inhibitor adding unit is used to add corrosion inhibitors to the cooling water pool to reduce the problem of pipe scaling and corrosion. Algaecides are added to remove algae produced in the cooling water pool to ensure the water quality of the circulating cooling water.

[0026] Furthermore, pressure detectors and temperature detectors are provided on the return pipe and the water supply pipe.

[0027] Beneficial effects: The pressure gauge and temperature detector are set to display the pipeline pressure and cooling water temperature in real time, which is convenient for adjusting the cooling efficiency of the cooling tower accordingly, as well as checking the pipeline pressure to ensure the normal operation of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic diagram of the connection structure of the esterification steam power generation cooling station;

[0029] Figure 2 for Figure 1 A top view of the cooling pool. DETAILED DESCRIPTION

[0030] The following is further described in detail through specific implementation methods:

[0031] The marks in the drawings of the specification include: cooling water tank 1, overflow pipe 101, sewage funnel 102, wastewater discharge pipe 11, water supply pipe 12, control valve 121, cooling tower 2, water supply pipe 3, first pressure-stabilizing tube 31, circulation pump 32, filter 321, pressure gauge 322, temperature detector 33, pressure detection gauge 34, return pipe 4, second pressure-stabilizing tube 43, conductivity online detector 5, scale inhibitor adding unit 61, algaecide adding unit 62.

[0032] Embodiment 1

[0033] like Figure 1 As shown, the online monitoring system for esterification power generation wastewater includes a cooling station for esterification steam power generation, the cooling station is provided with a cooling water pool 1 and a cooling tower 2, and specifically, in this embodiment, four groups of cooling towers 2 are provided, which are convenient for adjustment according to the circulating water temperature; the cooling water pool 1 is provided with a water supply pipe 12 and a wastewater discharge pipe 11, and the water supply pipe 12 and the wastewater discharge pipe 11 are both provided with a control valve 121, and specifically, the control valve 121 adopts a pneumatic valve; the cooling water pool 1 is also provided with a return pipe 4 and a water supply pipe 3, the water supply pipe 3 is connected to the water inlet of the condensing device, the return pipe 4 is connected to the water outlet of the condensing device, and the return pipe 4 is provided with an electric The conductivity online detector 5 is electrically connected to the control valve 121. When the conductivity online detector 5 detects that the conductivity in the return pipe 4 is greater than the preset value, the control valve 121 on the water supply pipe 12 and the wastewater discharge pipe 11 is controlled to be opened, and the opening of the control valve 121 on the water supply pipe 12 is greater than or equal to the opening of the control valve 121 on the wastewater discharge pipe 11. When the conductivity online detector 5 detects that the conductivity in the return pipe 4 is less than or equal to the preset value, the control valve 121 on the water supply pipe 12 and the wastewater discharge pipe 11 is controlled to be closed. The preset value of conductivity in this embodiment is 1500us / cm.

[0034] Four groups of circulation pumps 32 are also arranged in parallel on the water supply pipe 3, and the four groups of circulation pumps 32 include two groups of high-power circulation pumps and two groups of low-power circulation pumps. In this embodiment, the high-power circulation pump is 75KW, and the low-power circulation pump is 35KW; a filter 321 is arranged at the front end of each circulation pump 32, and a pressure gauge 322 is arranged at the rear end of the circulation pump 32; a first pressure-stabilizing tube 31 is also arranged on the water supply pipe 3, and the first pressure-stabilizing tube 31 is located at the rear end of the four groups of circulation pumps 32, and the water outlet of the first pressure-stabilizing tube 31 is connected to the cooling water pool 1. The first pressure-stabilizing tube 31 is arranged to stabilize the pressure of the water supply pipe 3 to avoid pressure buildup. At the same time, the water outlet of the first pressure-stabilizing tube 31 is connected to the cooling water pool 1, so as to realize the self-circulation of cooling water.

[0035] A second pressure-stabilizing tube 43 is also provided between the return pipe 4 and the water supply pipe 3. The cooling water in the second pressure-stabilizing tube 43 flows from the return pipe 4 to the water supply pipe 3. The second pressure-stabilizing tube 43 is provided to balance the pressure fluctuation in the pipeline and to supplement a certain amount of water to the water supply pipe 3. It can also avoid the cavitation phenomenon of the circulating water pump caused by too low system pressure, and optimize the working state of the circulating water pump by ensuring stable water pressure, thereby reducing the energy consumption of the system. At the same time, the continuous and stable cooling water pressure can reduce the pressure shock to various components in the system (such as pipelines and valves), reduce the fatigue damage and leakage risks caused by pressure fluctuations, and help to extend the service life of the equipment. In this embodiment, a pressure detection gauge 34 and a temperature detector 33 are also provided on the return pipe 4 and the water supply pipe 3, which are used to display the pipeline pressure and the temperature of the cooling water in real time, so as to adjust the cooling efficiency of the cooling tower 2 accordingly, and check the pipeline pressure to ensure the normal operation of the system.

[0036] In this embodiment, a plurality of overflow pipes 101 are arranged on the top of the cooling water pool 1, and the drain outlet of each overflow pipe 101 is connected to the wastewater discharge pipe 11; Figure 2 As shown, a number of drain funnels 102 are evenly arranged at the bottom of the cooling water pool 1. A drain pipe is arranged at the bottom of each drain funnel 102, and the drain pipe is connected to the wastewater discharge pipe 11. The drain funnel 102 is arranged to facilitate the deposition and discharge of sediment in the cooling water pool 1, for example, rust particles or impurities are deposited in the drain funnel 102 and discharged through the wastewater discharge pipe 11. The cooling water pool 1 is also provided with a reagent dosing unit, which is electrically connected to the control unit. The reagent dosing unit includes a scale inhibitor adding unit 61 and an algaecide adding unit 62. Specifically, the scale inhibitor adding unit 61 is used to add copper corrosion inhibitors, and the algaecide adding unit 62 is used to add oxidizing bactericidal algaecides and non-oxidizing bactericidal algaecides. The present application detects the conductivity through an online conductivity detector 5, and controls the discharge of wastewater and the replenishment of fresh water according to the detection data, which can effectively ensure the water quality of circulating water, and the reagent dosing unit is used to regularly add reagents to ensure that other water quality indicators of circulating water are normal and improve the stability of circulating water.

[0037] The technical solution provided by the present application is more accurate than the manual control of emissions before the transformation, can effectively avoid the risk of empty towers and tower jumping, and achieves the purpose of saving resources and reducing electricity consumption; and after the system transformation is actually put into use, it can ensure the long-term stable operation of the circulating water, and the wastewater is effectively monitored and discharged, and compared with the setting of multiple online detectors and control equipment, it saves the transformation cost and subsequent use and maintenance cost.

[0038] The above is only an embodiment of the utility model. The utility model is not limited to the field involved in this implementation case. The common knowledge such as the known specific structure and characteristics in the scheme is not described in detail here. It should be pointed out that for those skilled in the art, several deformations and improvements can be made without departing from the structure of the utility model, which should also be regarded as the protection scope of the utility model, and these will not affect the effect of the implementation of the utility model and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. Esterification power generation wastewater online monitoring system, characterized in that: It comprises a cooling station for esterification steam power generation, which is provided with a cooling water pool and a cooling tower, the cooling water pool is provided with a water supply pipe and a wastewater discharge pipe, both of which are provided with control valves, the cooling water pool is also provided with a return pipe and a water supply pipe, the water supply pipe is connected to the water inlet of a condensing device, and the return pipe is connected to the water outlet of the condensing device; the return pipe is provided with an online conductivity detector, which is electrically connected to the control valve, when the online conductivity detector detects that the conductivity in the return pipe is greater than a preset value, the control valves on the water supply pipe and the wastewater discharge pipe are controlled to be opened, and the opening of the control valve on the water supply pipe is greater than or equal to the opening of the control valve on the wastewater discharge pipe, when the online conductivity detector detects that the conductivity in the return pipe is less than or equal to the preset value, the control valves on the water supply pipe and the wastewater discharge pipe are controlled to be closed.

2. The online monitoring system for esterification power generation wastewater according to claim 1 is characterized by: Four groups of circulation pumps are arranged in parallel on the water supply pipe, and the four groups of circulation pumps include two groups of high-power circulation pumps and two groups of low-power circulation pumps.

3. The online monitoring system for esterification power generation wastewater according to claim 2 is characterized in that: A filter is provided at the front end of each circulating pump, and a pressure gauge is provided at the rear end of the circulating pump.

4. The online monitoring system for esterification power generation wastewater according to claim 3 is characterized by: A first pressure-stabilizing tube is also provided on the water supply pipe. The first pressure-stabilizing tube is located at the rear end of the four groups of circulation pumps, and the water outlet of the first pressure-stabilizing tube is connected to the cooling water pool.

5. The online monitoring system for esterification power generation wastewater according to claim 4 is characterized in that: A second pressure-stabilizing tube is also arranged between the return pipe and the water supply pipe, and the cooling water in the second pressure-stabilizing tube flows from the return pipe to the water supply pipe.

6. The online monitoring system for esterification power generation wastewater according to any one of claims 1 to 5, characterized in that: The bottom of the cooling water pool is evenly provided with sewage discharge funnels, and the bottom of each sewage discharge funnel is provided with a drainage pipe, which is connected to the wastewater discharge pipe.

7. The online monitoring system for esterification power generation wastewater according to claim 6 is characterized by: A plurality of overflow pipes are also arranged on the top of the cooling water pool, and the drain outlet of each overflow pipe is connected to the wastewater discharge pipe.

8. The online monitoring system for esterification power generation wastewater according to claim 7 is characterized by: The cooling water pool is also provided with a reagent dosing unit, which is electrically connected to the control unit. The reagent dosing unit includes a scale inhibitor adding unit and an algaecide adding unit.

9. The online monitoring system for esterification power generation wastewater according to claim 8, characterized in that: The return pipe and the water supply pipe are both provided with a pressure detection gauge and a temperature detection instrument.

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