A system for improving decolorization efficiency and a method thereof

Abstract

The present application relates to a kind of system and method for improving decolorization efficiency, system includes raw material tank, carbon component, first decoloring machine and second decoloring machine, the raw material outlet of raw material liquid tank is respectively communicated with first feed pipe and second feed pipe, first feed pipe is communicated with the feed port of first decoloring machine by first parallel pipeline, second feed pipe is communicated with the feed port of second decoloring machine by second parallel pipeline, intermediate pipeline is also set to be interconnected between first feed pipe and second feed pipe.The feed flow of first decoloring machine and second decoloring machine is controlled by adjusting valve and flowmeter, to ensure the independent operation of first decoloring machine and second decoloring machine, realize the controllable pressure and flow of first decoloring machine and second decoloring machine, prevent the adverse effects of high and low flow and pressure impact on first decoloring machine and second decoloring machine, greatly improve operating flow, prolong operating time, delay decolorization failure, prevent decoloring carbon leakage problem, improve decolorization efficiency.

Description

Technical Field

[0001] This invention belongs to the field of sugar alcohol preparation technology, and specifically relates to a system and method for improving decolorization efficiency. Background Technology

[0002] People's demand for sugar is increasing, and the application of sugar is becoming more widespread. Sugar production technology is also gradually maturing. Sugar decolorization is an essential process and technology in the sugar industry and has been used by enterprises for a long time. Food, medicine, industry and other industries have different requirements for the color value and color of sugar alcohols. After the continuous development of the starch sugar industry, activated carbon decolorization technology has become the most mainstream technology for sugar alcohol decolorization process. Commonly used activated carbon decolorization technologies include closed filtration decolorization and plate and frame filtration decolorization. However, due to the different properties of different sugar alcohol products, their viscosity and decolorization efficiency often vary greatly. The process operation cost has become one of the important reference conditions for enterprises to select processes. Common ways to improve the operating efficiency of sugar alcohol decolorization process include increasing the decolorization filtration area and using diatomaceous earth as a filter aid. However, problems often occur in the actual production process: (1) Increasing the decolorization filtration area will greatly increase the process investment and occupy a large area; (2) The improvement effect of diatomaceous earth as a filter aid is often not obvious due to the influence of material properties; (3) During operation, the pressure fluctuates greatly with the flow rate and operating time, which can easily lead to carbon leakage and affect product quality. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a system and method for improving decolorization efficiency, delaying decolorization failure, preventing decolorization carbon leakage, and improving decolorization efficiency.

[0004] This invention is implemented by providing a system for improving decolorization efficiency, comprising a raw material liquid tank for storing the raw material liquid to be decolorized, a carbon dispensing assembly, and a first decolorizing machine and a second decolorizing machine for decolorizing the raw material liquid. The carbon dispensing assembly includes a carbon dissolving tank, a diaphragm pump, and a carbon conveying pipeline. The carbon dissolving tank stores a uniformly mixed solution of activated carbon and diaphragm earth. The carbon conveying pipeline includes a carbon dissolving discharge pipe and a first carbon conveying pipe, a second carbon conveying pipe, and a third carbon conveying pipe connected in parallel with the carbon dissolving discharge pipe. The carbon dissolving discharge pipe is connected to the discharge port of the carbon dissolving tank. The diaphragm pump is installed at the carbon dissolving discharge port. On the feed pipeline, the first carbon feeding pipe is connected to the carbon dissolving inlet of the raw material liquid tank, the second carbon feeding pipe is connected to the inlet of the first decolorizing machine, and the third carbon feeding pipe is connected to the inlet of the second decolorizing machine. The raw material liquid tank is equipped with a raw material inlet, a carbon dissolving inlet, and a raw material outlet. The raw material outlet is connected to the first feed pipe and the second feed pipe. The first feed pipe is connected to the inlet of the first decolorizing machine through a first parallel pipeline, and the second feed pipe is connected to the inlet of the second decolorizing machine through a second parallel pipeline. A connection is also provided between the first feed pipe and the second feed pipe. The intermediate pipelines are interconnected, and the first feed pipe and the second feed pipe are connected in parallel. The discharge port of the first decolorizing machine is connected to the first direct current pipe, the first circulation pipe, and the first reflux pipe, respectively. The discharge port of the second decolorizing machine is connected to the second direct current pipe, the second circulation pipe, and the second reflux pipe, respectively. The first circulation pipe and the second circulation pipe are connected to the carbon dissolving tank, respectively. The first direct current pipe and the second direct current pipe are connected to the pipeline of the next process, respectively. The first reflux pipe and the second reflux pipe are connected to one inlet of the raw material liquid tank, respectively. A first feed pump is installed on the first feed pipe, and a second feed pump is installed on the second feed pipe. A first regulating valve, a first flow meter, and a first pressure sensor are installed on the first parallel pipeline. A second regulating valve, a second flow meter, and a second pressure sensor are installed on the second parallel pipeline. A first pneumatic valve is installed on the intermediate pipeline. A second pneumatic valve is installed on the first circulation pipe. A third pneumatic valve is installed on the second circulation pipe. A fourth pneumatic valve is installed on the first direct current pipe. A fifth pneumatic valve is installed on the second direct current pipe. A sixth pneumatic valve is installed on the first reflux pipe. A seventh pneumatic valve is installed on the second reflux pipe.

[0005] Furthermore, a signal connection is established between the first feed pump and the first pressure sensor, a signal connection is established between the second feed pump and the second pressure sensor, a signal connection is established between the first regulating valve and the first flow meter, and a signal connection is established between the second regulating valve and the second flow meter.

[0006] Furthermore, a third regulating valve and a third flow meter are also installed on the carbon dissolving discharge pipe, and a signal connection is provided between the third regulating valve and the third flow meter.

[0007] Furthermore, a pure water inlet pipe, an outlet for adding activated carbon and diatomaceous earth, and a carbon dissolving stirring device are respectively installed on the carbon dissolving tank.

[0008] Furthermore, an eighth pneumatic valve is installed on the first carbon feeding pipe, a ninth pneumatic valve is installed on the second carbon feeding pipe, and a tenth pneumatic valve is installed on the third carbon feeding pipe.

[0009] Furthermore, a raw material stirring device is provided in the raw material liquid tank.

[0010] This invention is implemented as follows, and also provides a method for improving decolorization efficiency, the method using the decolorization efficiency system as described above, comprising the following steps: Step 1: Turn on the diaphragm pump and the second pneumatic valve, and close the fourth and sixth pneumatic valves. The mixed solution in the carbon dissolving tank is transported to the raw material tank and the first decolorizing machine through the carbon conveying pipeline. The mixed solution enters the first decolorizing machine as a pre-coated filter cake. After the mixed solution flows through the first decolorizing machine, the activated carbon in it is filtered and accumulated in the first decolorizing machine to become a filter cake. The filtered mixed solution is circulated back to the carbon dissolving tank through the first circulation pipe connected to the discharge port for reuse. The circulation is repeated until the filter cake is completed.

[0011] Step 2: Turn on the first feed pump and the sixth pneumatic valve, and close the first and second pneumatic valves. The mixed liquid after mixing the raw material liquid and the mixed solution is transported to the first decolorizing machine for decolorization. Before the decolorized liquid at the outlet of the first decolorizing machine becomes clear, the decolorized liquid from the first decolorizing machine flows back to the raw material liquid tank through the first return pipe connected to the outlet for reuse. Repeat the above cycle until the decolorized liquid at the outlet of the first decolorizing machine becomes clear and the light transmittance reaches or exceeds the lower limit of light transmittance. Then, close the sixth pneumatic valve and open the fourth pneumatic valve. The decolorized liquid from the first decolorizing machine switches to flow to the next process through the first direct current pipe. The system continues to operate at the set required flow rate.

[0012] Step 3: When the operating pressure of the first pressure sensor monitoring system reaches the set pressure, open the third pneumatic valve and close the fifth and seventh pneumatic valves. The mixed solution is then transported to the second decolorizing machine via the carbon conveying pipeline. The mixed solution enters the second decolorizing machine as a pre-coated filter cake. After flowing through the second decolorizing machine, the activated carbon is filtered and accumulated, forming a filter cake. The filtered mixed solution is then circulated back to the carbon dissolving tank via the second circulation pipe connected to the outlet for reuse. This circulation is repeated until the filter cake is formed. Then, open the second feed pump and the seventh pneumatic valve, and close the third and fifth pneumatic valves to transport the mixed liquid to the second decolorizing machine for decolorization. Before the decolorized liquid at the outlet of the second decolorizing machine becomes clear, it is returned to the raw material tank via the second return pipe connected to the outlet for reuse.

[0013] Step 4: When the flow rate of the decolorizing liquid at the outlet of the first decolorizing machine begins to decrease and the decolorizing liquid at the outlet of the second decolorizing machine becomes clear and the light transmittance reaches or exceeds the lower limit value, open the fifth pneumatic valve and close the seventh pneumatic valve. The decolorizing liquid from the second decolorizing machine will then flow through the pipeline connected to the second DC pipe to the next process. The operating flow rate of the second decolorizing machine will be gradually increased according to the decreasing flow rate of the first decolorizing machine. When the operating flow rate of the first decolorizing machine drops to the set lower limit flow rate, close the first feed pump and the fourth pneumatic valve. The second decolorizing machine will continue to operate at the set flow rate. Perform air-top and water-top carbon unloading and cleaning operations on the first decolorizing machine, and after regeneration and recovery, it will be used as a backup.

[0014] Step 5: When the operating pressure of the second pressure sensor monitoring system reaches the set pressure, refer to Step 3 to prepare the pre-coated filter cake for the first decolorizing machine and the preparations for the first decolorizing machine to be added to the system for operation.

[0015] Step 6: Referring to Steps 4 and 5, alternate between the operation of the first decolorizing machine and the second decolorizing machine to ensure continuous system operation.

[0016] Furthermore, the method also includes: during the operation of the system, periodically monitoring the light transmittance of the decolorizing liquid at the outlets of the first and second decolorizing machines.

[0017] Compared with the prior art, the present invention provides a system and method for improving decolorization efficiency. The system includes a raw material tank, a carbon mixing assembly, a first decolorizing machine, and a second decolorizing machine. The raw material outlet of the raw material tank is connected to a first feed pipe and a second feed pipe. The first feed pipe is connected to the inlet of the first decolorizing machine via a first parallel pipeline, and the second feed pipe is connected to the inlet of the second decolorizing machine via a second parallel pipeline. An intermediate pipeline connects the first and second feed pipes. The outlet of the first decolorizing machine is connected to a first direct current pipe, a first circulation pipe, and a first reflux pipe. The outlet of the second decolorizing machine is connected to a second direct current pipe, a second circulation pipe, and a second reflux pipe. The first and second circulation pipes are connected to the carbon dissolving tank of the carbon mixing assembly. The first and second direct current pipes are connected to the pipeline of the next process. The first and second reflux pipes are connected to one inlet of the raw material tank. The feed flow rates of the first and second decolorizing machines are controlled by regulating valves and flow meters, ensuring independent operation of both machines. This allows for controllable pressure and flow rates in both machines, preventing adverse effects from high / low flow rates and pressure shocks. It significantly increases operating flow, extends operating time, delays decolorization failure, prevents carbon leakage during decolorization, and improves decolorization efficiency. The carbon distribution unit not only adds carbon to the raw material tank but also to each decolorizing machine, enabling independent filter cake production in different machines and ensuring the system's decolorization effect without mutual interference. Attached Figure Description

[0018] Figure 1 This is a schematic diagram illustrating the structural principle of a preferred embodiment of the system for improving decolorization efficiency according to the present invention. Detailed Implementation

[0019] To make the technical problems to be solved, the technical solutions, and the beneficial effects of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present invention and are not intended to limit the present invention.

[0020] Please refer to Figure 1 As shown, a preferred embodiment of the system for improving decolorization efficiency of the present invention includes a raw material liquid tank 1 for storing the raw material liquid to be decolorized, a carbon dispensing assembly, and a first decolorizing machine 2 and a second decolorizing machine 3 for decolorizing the raw material liquid. The carbon dispensing assembly includes a carbon dissolving tank 4, a diaphragm pump 5, and a carbon conveying pipeline. The carbon conveying pipeline includes a carbon dissolving discharge pipe 6 and a first carbon conveying pipe 7, a second carbon conveying pipe 8, and a third carbon conveying pipe 9 connected in parallel with the carbon dissolving discharge pipe 6.

[0021] The carbon dissolving tank 4 stores a uniformly mixed solution of activated carbon and diatomaceous earth. The carbon dissolving discharge pipe 6 is connected to the discharge port of the carbon dissolving tank 4. The diaphragm pump 5 is installed on the carbon dissolving discharge pipe 6. The first carbon feeding pipe 7 is connected to the carbon dissolving inlet of the raw material liquid tank 1, the second carbon feeding pipe 8 is connected to the inlet of the first decolorizing machine 2, and the third carbon feeding pipe 9 is connected to the inlet of the second decolorizing machine 3.

[0022] The raw material tank 1 is equipped with a raw material inlet, a carbonization inlet, and a raw material outlet. The raw material inlet is connected to the raw material inlet pipe 10. The raw material outlet is connected to a first inlet pipe 11 and a second inlet pipe 12. The first inlet pipe 11 is connected to the inlet of the first decolorizing machine 2 through a first parallel pipe 13, and the second inlet pipe 12 is connected to the inlet of the second decolorizing machine 3 through a second parallel pipe 14. An intermediate pipe 15 is also provided between the first inlet pipe 11 and the second inlet pipe 12 to connect them, and the first inlet pipe 11 and the second inlet pipe 12 are connected in parallel.

[0023] The discharge port of the first decolorizing machine 2 is connected to the first direct current pipe 16, the first circulation pipe 17, and the first reflux pipe 40, respectively. The discharge port of the second decolorizing machine 3 is connected to the second direct current pipe 18, the second circulation pipe 19, and the second reflux pipe 40, respectively. The first circulation pipe 17 and the second circulation pipe 19 are respectively connected to the carbon dissolving tank 4 of the carbon mixing component. The first direct current pipe 16 and the second direct current pipe 18 are respectively connected to the pipeline of the next process. The first reflux pipe 40 and the second reflux pipe 41 are respectively connected to one inlet of the raw material liquid tank 1. The first decolorizing machine 2 and the second decolorizing machine 3 switch between each other. When the first decolorizing machine 2 is in use or standby, the second decolorizing machine 3 is in standby or use, respectively.

[0024] A first feed pump 20 is installed on the first feed pipe 11, and a second feed pump 21 is installed on the second feed pipe 12. A first regulating valve 22, a first flow meter 23, and a first pressure sensor 24 are sequentially installed on the first parallel pipeline 13. A second regulating valve 25, a second flow meter 26, and a second pressure sensor 27 are sequentially installed on the second parallel pipeline 14. A first pneumatic valve 28 is installed on the intermediate pipeline 15. The first pneumatic valve 28 controls the interconnection and switching of the intermediate pipelines 15.

[0025] The mixed liquid from the first feed pipe 11 can enter the second parallel pipe 14 through the intermediate pipe 15, and the mixed liquid from the second feed pipe 12 can also enter the first parallel pipe 13 through the intermediate pipe 15. Under normal use, the first pneumatic valve 28 on the intermediate pipe 15 is closed. When either the first feed pump 20 or the second feed pump 21 malfunctions and requires maintenance, the other pump can be switched immediately by opening the first pneumatic valve 28 to meet production needs.

[0026] A second pneumatic valve 34 is provided on the first circulation pipe 17, a third pneumatic valve 35 is provided on the second circulation pipe 19, a fourth pneumatic valve 44 is provided on the first direct current pipe 16, a fifth pneumatic valve 45 is provided on the second direct current pipe 18, a sixth pneumatic valve 42 is provided on the first return pipe 40, and a seventh pneumatic valve 43 is provided on the second return pipe 41.

[0027] A signal connection is established between the first feed pump 20 and the first pressure sensor 24. The first pressure sensor 24 adjusts the operation of the first feed pump 20 according to a set pressure to maintain a stable pressure of the mixed liquid in the first feed pipe 11. A signal connection is established between the second feed pump 21 and the second pressure sensor 27. The second pressure sensor 27 adjusts the operation of the second feed pump 21 according to a set pressure to maintain a stable pressure of the mixed liquid in the second feed pipe 13. A signal connection is established between the first regulating valve 22 and the first flow meter 23. The flow rate set by the first flow meter 23 adjusts the first regulating valve 22 to regulate the flow rate of the first parallel pipeline 13. A signal connection is established between the second regulating valve 25 and the second flow meter 26. The flow rate set by the second flow meter 26 adjusts the second regulating valve 25 to regulate the flow rate of the second parallel pipeline 14.

[0028] The first decolorizing machine 2 and the second decolorizing machine 3 operate independently, so that the pressure and flow of the first decolorizing machine 2 and the second decolorizing machine 3 are controllable. This prevents the adverse effects of high and low flow and pressure shocks on the first decolorizing machine 2 and the second decolorizing machine 3, greatly increases the operating flow, extends the operating time, delays decolorization failure, prevents decolorization carbon leakage problems, and improves decolorization efficiency.

[0029] A third regulating valve 29 and a third flow meter 30 are sequentially installed on the carbon dissolving discharge pipe 6. A signal connection is provided between the third regulating valve 29 and the third flow meter 30. The flow rate set by the third flow meter 30 is used to adjust the third regulating valve 29, thereby achieving the purpose of regulating the flow rate of the carbon dissolving discharge pipe 6.

[0030] The carbon dissolving tank 4 is equipped with a pure water inlet pipe 31, an inlet 32 ​​for adding activated carbon and diatomaceous earth, and a carbon dissolving stirring device 33. The carbon dissolving stirring device 33 is driven to ensure that the pure water, activated carbon, and diatomaceous earth are fully and evenly mixed.

[0031] An eighth pneumatic valve 36 is provided on the first carbon feeding pipe 7, a ninth pneumatic valve 37 is provided on the second carbon feeding pipe 8, and a tenth pneumatic valve 38 is provided on the third carbon feeding pipe 9.

[0032] A raw material stirring device 39 is installed in the raw material tank 1. The raw material stirring device 39 is driven to fully mix the raw material liquid with the mixed solution to form a mixed liquid.

[0033] The present invention also discloses a method for improving decolorization efficiency, the method using the decolorization efficiency system described above, comprising the following steps: Step 1: Turn on the diaphragm pump 5 and the second pneumatic valve 34, and close the fourth pneumatic valve 44 and the sixth pneumatic valve 42. The mixed solution in the carbon dissolving tank 4 is transported to the raw material liquid tank 1 and the first decolorizing machine 2 through the carbon conveying pipeline. The mixed solution enters the first decolorizing machine 2 as a pre-coated filter cake. After the mixed solution flows through the first decolorizing machine 2, the activated carbon in it is filtered and accumulated in the first decolorizing machine 2 to become a filter cake. The filtered mixed solution is circulated back to the carbon dissolving tank 4 through the first circulation pipe 17 connected to the discharge port for reuse until the filter cake is completed.

[0034] Step 2: Start the first feed pump 20 and the sixth pneumatic valve 42, and close the first pneumatic valve 28 and the second pneumatic valve 34. The mixed liquid, after mixing the raw material liquid and the mixed solution, is transported to the first decolorizing machine 2 for decolorization. Before the decolorized liquid at the outlet of the first decolorizing machine 2 becomes clear, it flows back to the raw material liquid tank 1 through the first return pipe 40 connected to the outlet for reuse. Repeat this cycle until the decolorized liquid at the outlet of the first decolorizing machine 2 becomes clear and its light transmittance reaches or exceeds the lower limit of light transmittance. Then, close the sixth pneumatic valve 42 and open the fourth pneumatic valve 44. The decolorized liquid from the first decolorizing machine 2 then flows to the next process through the first direct current pipe 16 connected to the outlet. The system operates continuously at the set required flow rate.

[0035] Step 3: When the operating pressure of the system monitored by the first pressure sensor 24 reaches the set pressure, the third pneumatic valve 35 is opened, and the fifth pneumatic valve 45 and the seventh pneumatic valve 43 are closed. The mixed solution is then transported to the second decolorizing machine 3 through the carbon conveying pipeline. The mixed solution enters the second decolorizing machine 3 as a pre-coated filter cake. After the mixed solution flows through the second decolorizing machine 3, the activated carbon in it is filtered and accumulated in the second decolorizing machine 3 to form a filter cake. The filtered mixed solution is circulated back to the carbon dissolving tank 4 through the second circulation pipe 19 connected to the discharge port for reuse. This circulation is repeated until the filter cake is formed. The second feed pump 21 and the seventh pneumatic valve 43 are opened, and the third pneumatic valve 35 and the fifth pneumatic valve 45 are closed. The mixed liquid is then transported to the second decolorizing machine 3 for decolorization treatment. Before the decolorized liquid at the discharge port of the second decolorizing machine 3 becomes clear, the decolorized liquid in the second decolorizing machine 3 is returned to the raw material liquid tank 1 through the second return pipe 41 connected to the discharge port for reuse.

[0036] Step 4: When the flow rate of the decolorizing liquid at the outlet of the first decolorizing machine 2 begins to decrease and the decolorizing liquid at the outlet of the second decolorizing machine 3 becomes clear and the light transmittance reaches or exceeds the lower limit of light transmittance, open the fifth pneumatic valve 45 and close the seventh pneumatic valve 43. The decolorizing liquid of the second decolorizing machine 3 switches to flow to the next process through the pipeline connected to the second DC pipe 18. The operating flow rate of the second decolorizing machine 3 is gradually adjusted upward according to the decreasing flow rate of the first decolorizing machine 2. When the operating flow rate of the first decolorizing machine 2 drops to the set lower limit flow rate, close the first feed pump 20 and the fourth pneumatic valve 44, and the second decolorizing machine 3 continues to operate at the set flow rate. Perform air-top and water-top carbon unloading and cleaning operations on the first decolorizing machine 2, and use it as a backup after regeneration and recovery.

[0037] Step 5: When the operating pressure of the system monitored by the second pressure sensor 27 reaches the set pressure, refer to Step 3 to prepare the pre-coated filter cake of the first decolorizing machine 2 for use and the preparations before the first decolorizing machine 2 is added to the system for operation.

[0038] Step 6: Referring to steps 4 and 5, alternate the operation of the first decolorizing machine 2 and the second decolorizing machine 3 to ensure continuous system operation.

[0039] The method further includes: during the operation of the system, periodically monitoring the light transmittance of the decolorizing liquid at the outlets of the first decolorizing machine 2 and the second decolorizing machine 3 to ensure that the light transmittance of the decolorizing liquid is greater than the lower limit of light transmittance.

[0040] The system and method for improving decolorization efficiency of the present invention are further illustrated below through specific embodiments.

[0041] Example 1

[0042] A first embodiment of the method for improving decolorization efficiency of the present invention includes the following steps: Step 11: Add 20 kg of activated carbon, 20 kg of diatomaceous earth, and 0.6 m³ of pure water to the carbon dissolving tank 4 and stir thoroughly to obtain a uniformly mixed solution. Turn on the diaphragm pump 5 and the second pneumatic valve 34, and close the fourth pneumatic valve 44 and the sixth pneumatic valve 42. The mixed solution in the carbon dissolving tank 4 is then transported to the raw material tank 1 and the first decolorizing machine 2 through the carbon conveying pipeline. The mixed solution enters the first decolorizing machine 2 as a pre-coated filter cake. Add 10 kg of activated carbon to the raw material tank 1 at a dry basis rate of 0.5 kg / t, and stir for 30 minutes at a temperature of 65°C.

[0043] Step 12: Turn on the first feed pump 20 and the sixth pneumatic valve 42, and close the first pneumatic valve 28 and the second pneumatic valve 34. The mixed liquid is then transported to the first decolorizing machine 2 for decolorization. The maximum flow rate of the first flow meter 23 is set to 20 m³ / h, and the maximum pressure of the first pressure sensor 24 is set to 0.45 MPa. Before the decolorized liquid at the outlet of the first decolorizing machine 2 becomes clear, it flows back to the raw material tank 1 through the first return pipe 40 connected to the outlet for reuse. This continues until the decolorized liquid at the outlet of the first decolorizing machine 2 becomes clear and its light transmittance reaches or exceeds the lower limit of light transmittance. Then, the sixth pneumatic valve 42 is closed, and the fourth pneumatic valve 44 is opened. The decolorized liquid from the first decolorizing machine 2 is switched to flow to the next process through the first direct current pipe 16. The system operates continuously at the set required flow rate of 12 m³ / h. During system operation, the light transmittance of the decolorized liquid is sampled and tested every 2 hours.

[0044] Step 13: When the operating pressure of the system monitored by the first pressure sensor 24 reaches the set pressure of 0.4 MPa, open the third pneumatic valve 35 and close the fifth pneumatic valve 45 and the seventh pneumatic valve 43. The mixed solution is then transported to the second decolorizing machine 3 through the carbon conveying pipeline. The mixed solution enters the second decolorizing machine 3 as a pre-coated filter cake. Open the second feed pump 21 and the seventh pneumatic valve 43, and close the third pneumatic valve 35 and the fifth pneumatic valve 45. The mixed liquid is then transported to the second decolorizing machine 3 for decolorization. Before the decolorized liquid at the outlet of the second decolorizing machine 3 becomes clear, the decolorized liquid from the second decolorizing machine 3 is returned to the raw material tank 1 through the second return pipe 41 connected to the outlet for reuse.

[0045] Step 14: When the flow rate of the decolorizing liquid at the outlet of the first decolorizing machine 2 begins to decrease and the decolorizing liquid at the outlet of the second decolorizing machine 3 becomes clear and the light transmittance reaches above the lower limit value, open the fifth pneumatic valve 45 and close the seventh pneumatic valve 43. The decolorizing liquid of the second decolorizing machine 3 is switched to flow to the pipeline of the next process through the second DC pipe 18. The operating flow rate of the second decolorizing machine 3 is gradually adjusted upward according to the decreasing flow rate of the first decolorizing machine 2. When the operating flow rate of the first decolorizing machine 2 drops to the set lower limit flow rate of 6.0 m³ / h, the first feed pump 20 is turned off, and the second decolorizing machine 3 continues to operate at the set flow rate of 12 m³ / h. The first decolorizing machine 2 is subjected to air-top and water-top carbon unloading and cleaning operations, and is then regenerated and restored for standby.

[0046] Step 15: When the operating pressure of the system monitored by the second pressure sensor 27 reaches the set pressure of 0.4 MPa, refer to step 13 to prepare the pre-coated filter cake of the first decolorizing machine 2 for use and the preparations before the first decolorizing machine 2 is added to the system for operation.

[0047] Step 16: Referring to steps 14 to 15, the first decolorizing machine 2 and the second decolorizing machine 3 are operated alternately and repeatedly to ensure continuous operation of the system.

[0048] In this embodiment, the high-flow operation time is 30 hours, and the material feed rate is 576m³. 3 The existing decolorization system operates at high flow rates for 20 hours with a feed rate of 312m³. 3 The system of this invention is significantly more effective than existing systems.

[0049] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A system for improving decolorization efficiency, characterized in that, The system includes a raw material tank for storing the raw material solution to be decolorized, a carbon dispensing assembly, and a first and second decolorizing machine for decolorizing the raw material solution. The carbon dispensing assembly includes a carbon dissolving tank, a diaphragm pump, and carbon conveying pipelines. The carbon dissolving tank stores a uniformly mixed solution of activated carbon and diaphragm earth. The carbon conveying pipelines include a carbon dissolving discharge pipe and a first, second, and third carbon conveying pipe connected in parallel with the carbon dissolving discharge pipe. The carbon dissolving discharge pipe is connected to the discharge port of the carbon dissolving tank. The diaphragm pump is installed on the carbon dissolving discharge pipe. The first carbon conveying pipe is connected to the carbon dissolving tank. The feed inlets are connected, the second carbon feeding pipe is connected to the feed inlet of the first decolorizing machine, and the third carbon feeding pipe is connected to the feed inlet of the second decolorizing machine. The raw material liquid tanks are respectively equipped with a raw material feed inlet, a carbon dissolving feed inlet, and a raw material discharge outlet. The raw material discharge outlet is connected to a first feed pipe and a second feed pipe. The first feed pipe is connected to the feed inlet of the first decolorizing machine through a first parallel pipe, and the second feed pipe is connected to the feed inlet of the second decolorizing machine through a second parallel pipe. An intermediate pipe is also provided between the first feed pipe and the second feed pipe for mutual connection. The feed pipe and the second feed pipe are connected in parallel. The discharge port of the first decolorizing machine is connected to the first direct current pipe, the first circulation pipe, and the first reflux pipe. The discharge port of the second decolorizing machine is connected to the second direct current pipe, the second circulation pipe, and the second reflux pipe. The first circulation pipe and the second circulation pipe are connected to the carbon dissolving tank. The first direct current pipe and the second direct current pipe are connected to the pipeline of the next process. The first reflux pipe and the second reflux pipe are connected to one inlet of the raw material liquid tank. A first feed pump is installed on the first feed pipe, and a second feed pump is installed on the second feed pipe. A first regulating valve, a first flow meter, and a first pressure sensor are installed on the first parallel pipeline. A second regulating valve, a second flow meter, and a second pressure sensor are installed on the second parallel pipeline. A first pneumatic valve is installed on the intermediate pipeline. A second pneumatic valve is installed on the first circulation pipe. A third pneumatic valve is installed on the second circulation pipe. A fourth pneumatic valve is installed on the first direct current pipe. A fifth pneumatic valve is installed on the second direct current pipe. A sixth pneumatic valve is installed on the first reflux pipe. A seventh pneumatic valve is installed on the second reflux pipe.

2. The system for improving decolorization efficiency as described in claim 1, characterized in that, A signal connection is established between the first feed pump and the first pressure sensor, a signal connection is established between the second feed pump and the second pressure sensor, a signal connection is established between the first regulating valve and the first flow meter, and a signal connection is established between the second regulating valve and the second flow meter.

3. The system for improving decolorization efficiency as described in claim 1, characterized in that, A third regulating valve and a third flow meter are also installed on the carbon dissolution discharge pipe, and a signal connection is provided between the third regulating valve and the third flow meter.

4. The system for improving decolorization efficiency as described in claim 3, characterized in that, The carbon dissolving tank is equipped with a pure water inlet pipe, an outlet for adding activated carbon and diatomaceous earth, and a carbon dissolving stirring device.

5. The system for improving decolorization efficiency as described in claim 1, characterized in that, An eighth pneumatic valve is installed on the first carbon feeding pipe, a ninth pneumatic valve is installed on the second carbon feeding pipe, and a tenth pneumatic valve is installed on the third carbon feeding pipe.

6. The system for improving decolorization efficiency as described in claim 1, characterized in that, A raw material stirring device is installed in the raw material liquid tank.

7. A method for improving decolorization efficiency, characterized in that, The method uses the system for improving decolorization efficiency as described in any one of claims 1 to 6, and includes the following steps: Step 1: Turn on the diaphragm pump and the second pneumatic valve, and close the fourth and sixth pneumatic valves. The mixed solution in the carbon dissolving tank is transported to the raw material tank and the first decolorizing machine through the carbon conveying pipeline. The mixed solution enters the first decolorizing machine as a pre-coated filter cake. After the mixed solution flows through the first decolorizing machine, the activated carbon in it is filtered and accumulated in the first decolorizing machine to become a filter cake. The filtered mixed solution is returned to the carbon dissolving tank through the first circulation pipe connected to the discharge port for reuse. The cycle is repeated until the filter cake is completed. Step 2: Turn on the first feed pump and the sixth pneumatic valve, and close the first and second pneumatic valves. The mixed liquid after mixing the raw material liquid and the mixed solution is transported to the first decolorizing machine for decolorization. Before the decolorized liquid at the outlet of the first decolorizing machine becomes clear, the decolorized liquid from the first decolorizing machine flows back to the raw material liquid tank through the first return pipe connected to the outlet for reuse. Repeat the above cycle until the decolorized liquid at the outlet of the first decolorizing machine becomes clear and the light transmittance reaches or exceeds the lower limit of light transmittance. Then, close the sixth pneumatic valve and open the fourth pneumatic valve. The decolorized liquid from the first decolorizing machine switches to flow to the next process through the first direct current pipe. The system continues to operate at the set required flow rate. Step 3: When the operating pressure of the first pressure sensor monitoring system reaches the set pressure, open the third pneumatic valve and close the fifth and seventh pneumatic valves. The mixed solution is then transported to the second decolorizing machine through the carbon conveying pipeline. The mixed solution enters the second decolorizing machine as a pre-coated filter cake. After the mixed solution flows through the second decolorizing machine, the activated carbon in it is filtered and accumulated in the second decolorizing machine to form a filter cake. The filtered mixed solution is circulated back to the carbon dissolving tank through the second circulation pipe connected to the discharge port for reuse. This cycle is repeated until the filter cake is formed. Then, open the second feed pump and the seventh pneumatic valve, and close the third and fifth pneumatic valves to transport the mixed liquid to the second decolorizing machine for decolorization. Before the decolorized liquid at the discharge port of the second decolorizing machine becomes clear, the decolorized liquid in the second decolorizing machine is returned to the raw material liquid tank through the second return pipe connected to the discharge port for reuse. Step 4: When the flow rate of the decolorizing liquid at the outlet of the first decolorizing machine begins to decrease and the decolorizing liquid at the outlet of the second decolorizing machine becomes clear and the light transmittance reaches or exceeds the lower limit of light transmittance, open the fifth pneumatic valve and close the seventh pneumatic valve. The decolorizing liquid from the second decolorizing machine will then flow through the second DC pipe to the pipeline of the next process. The operating flow rate of the second decolorizing machine will be gradually increased according to the decreasing flow rate of the first decolorizing machine. When the operating flow rate of the first decolorizing machine drops to the set lower limit flow rate, close the first feed pump and the fourth pneumatic valve. The second decolorizing machine will continue to operate at the set flow rate. Perform air-top and water-top carbon unloading and cleaning operations on the first decolorizing machine, and use it as a backup after regeneration and recovery. Step 5: When the operating pressure of the second pressure sensor monitoring system reaches the set pressure, refer to Step 3 to prepare the pre-coated filter cake for the first decolorizing machine and the preparations for the first decolorizing machine to be added to the system for operation. Step 6: Referring to Steps 4 and 5, alternate between the operation of the first decolorizing machine and the second decolorizing machine to ensure continuous system operation.

8. The method for improving decolorization efficiency as described in claim 7, characterized in that, The method further includes: during the operation of the system, periodically monitoring the light transmittance of the decolorizing liquid at the outlets of the first and second decolorizing machines.

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