A system and method for monitoring the deionization capacity of ion exchange resin

Abstract

The invention discloses a system and method for monitoring the deionization capacity of an ion exchange resin, comprising a controller, an electromagnetic flowmeter, an inlet water conductivity meter, an ion exchange resin bed and an outlet water conductivity meter; the electromagnetic flowmeter and the inlet water conductivity meter are installed on the inlet pipe of the ion exchange resin bed, and the outlet water conductivity meter is installed on the outlet pipe of the ion exchange resin bed; the electromagnetic flowmeter, the inlet water conductivity meter and the outlet water conductivity meter are connected to the controller; the system and method accurately monitor the ion load accepted by the ion exchange resin, predict the resin failure time, and issue an early warning before the impurity ions penetrate the resin to prevent the downstream water quality from being polluted.

Description

Technical Field

[0001] The invention belongs to the technical field of water treatment in power plants and relates to a system and method for monitoring the deionization capacity of ion exchange resin. Background Art

[0002] Ion exchange resins can be used to remove various anions and cations from water, thereby producing high-purity water. They are widely used in power plants. The process from the initial commissioning of an ion exchange resin to its decommissioning after failure is called an operating cycle. Resin failure should be promptly decommissioned, otherwise the effluent will carry impurity ions, potentially harming downstream thermal equipment and pipelines. However, if the resin operating cycle is too short and regenerated frequently to ensure effluent quality, not only will large amounts of acid, alkali, and flushing water be consumed, but also large amounts of acid and alkali wastewater will be generated. Therefore, accurately determining the operating cycle of ion exchange resins is crucial for ensuring effluent quality, protecting system equipment and pipelines, conserving acid and alkali usage, and reducing wastewater discharge.

[0003] Currently, operators typically use the following methods to determine the extent of resin failure: 1) cation resin failure based on the sodium ion concentration of the effluent; 2) anion resin failure based on the electrical conductivity of the effluent; and 3) mixed-bed resin failure based on the electrical conductivity, sodium ion concentration, and silicon content of the effluent. While these methods can effectively determine ion exchange resin failure, they can only detect it after impurity ions have penetrated the resin. By then, the water containing impurity ions has already entered the downstream system, posing risks of corrosion, scaling, and salt accumulation to thermal equipment and pipelines. Summary of the Invention

[0004] The purpose of the present invention is to overcome the shortcomings of the above-mentioned prior art and provide a system and method for monitoring the deionization capacity of ion exchange resins. The system and method accurately monitor the ion load accepted by the ion exchange resin, predict the failure time of the resin, and issue an early warning before the impurity ions penetrate the resin, thereby preventing downstream water quality from being polluted.

[0005] To achieve the above-mentioned object, the system for monitoring the deionization capacity of an ion exchange resin of the present invention comprises a controller, an electromagnetic flowmeter, an inlet water conductivity meter, an ion exchange resin bed and an outlet water conductivity meter;

[0006] The electromagnetic flowmeter and the inlet water conductivity meter are installed on the inlet pipe of the ion exchange resin bed, and the outlet water conductivity meter is installed on the outlet pipe of the ion exchange resin bed. The electromagnetic flowmeter, the inlet water conductivity meter and the outlet water conductivity meter are connected to the controller.

[0007] The device also includes a comparative conductivity meter, which is installed on the side of the ion exchange resin bed and is connected to the controller.

[0008] The vertical distance from the conductivity meter to the bottom of the ion exchange resin bed is 15% of the height of the ion exchange resin bed.

[0009] The electromagnetic flowmeter, the inlet water conductivity meter, the comparison conductivity meter and the outlet water conductivity meter are connected to the controller through a signal transmission cable.

[0010] The method for monitoring the deionization capacity of an ion exchange resin according to the present invention comprises the following steps:

[0011] The influent water flows into the ion exchange resin bed through the electromagnetic flowmeter and the influent conductivity meter. The influent flow rate q is measured by the electromagnetic flowmeter, and the influent conductivity κ1 is measured by the influent conductivity meter. The controller calculates the ion concentration e1 in the influent water based on the influent conductivity κ1.

[0012] The outlet water conductivity κ2 is measured by the outlet water conductivity meter, and the controller calculates the ion concentration e2 in the outlet water according to the outlet water conductivity κ2;

[0013] Multiply the difference Δe between e1 and e2 by the flow rate q, and then integrate it with the running time t to obtain the ion load A entering the ion exchange resin bed, that is:

[0014] A=∫ t q×Δe

[0015] The maximum deionization capacity of the ion exchange resin is set to I. When A reaches I, it is determined that the resin is about to fail, and the controller issues a resin failure warning.

[0016] A comparative conductivity meter is provided on the side of the ion exchange resin bed and is connected to the controller.

[0017] The vertical distance from the conductivity meter to the bottom of the ion exchange resin bed is 15% of the height of the ion exchange resin bed.

[0018] Conductivity κ is controlled by comparing with the conductivity meter c , κ c The ratio of κ2 is used as the control parameter R:

[0019] R = κ c / κ2

[0020] During normal operation, the value of R is maintained at 1.0. When R deviates from 1.0 and the value of A does not reach 1, the controller issues a resin failure warning and records the ion load A accepted by the ion exchange resin bed at this time. i , and use A i Revision I.

[0021] The present invention has the following beneficial effects:

[0022] During specific operation, the system and method for measuring the deionization capacity of an ion exchange resin described in the present invention measures the inlet flow rate q using an electromagnetic flowmeter, measures the inlet water conductivity κ1 using an inlet water conductivity meter, and measures the outlet water conductivity κ2 using an outlet water conductivity meter. This accurately monitors the amount of ions exchanged by the resin, predicts the resin failure time, and issues a warning before impurity ions penetrate to prevent downstream water quality from being polluted. At the same time, changes in the resin working capacity are recorded, the performance and life of the resin are evaluated, and the management efficiency of operating personnel is improved. In addition, the present invention is not affected by changes in the inlet water flow rate and the inlet water ion concentration, and has high measurement accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a structural schematic diagram of the present invention;

[0024] Figure 2 Flow chart of the method of the present invention.

[0025] Among them, 1 is the controller, 2 is the electromagnetic flowmeter, 3 is the inlet water conductivity meter, 4 is the ion exchange resin bed, 5 is the comparative conductivity meter, and 6 is the outlet water conductivity meter. DETAILED DESCRIPTION

[0026] In order to enable those skilled in the art to better understand the solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only embodiments of a part of the present invention, not all embodiments, and are not intended to limit the scope of the present invention. In addition, in the following description, descriptions of well-known structures and technologies are omitted to avoid unnecessary confusion of the concepts disclosed in the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of protection of the present invention.

[0027] The accompanying drawings illustrate schematic diagrams of the structures of the disclosed embodiments of the present invention. These figures are not drawn to scale; for the purpose of clarity, some details are exaggerated and some details may be omitted. The shapes of the various regions and layers shown in the figures, as well as their relative sizes and positional relationships, are merely exemplary and may deviate in practice due to manufacturing tolerances or technical limitations. Those skilled in the art may design regions / layers with different shapes, sizes, and relative positions as needed.

[0028] refer to Figure 1 The system and method for monitoring the deionization capacity of an ion exchange resin according to the present invention include a controller 1, an electromagnetic flowmeter 2, an inlet water conductivity meter 3, an ion exchange resin bed 4, a comparative conductivity meter 5, and an outlet water conductivity meter 6;

[0029] The electromagnetic flowmeter 2 and the inlet water conductivity meter 3 are installed on the inlet pipe of the ion exchange resin bed 4, the comparative conductivity meter 5 is installed on the side of the ion exchange resin bed 4, and the vertical distance from the comparative conductivity meter 5 to the bottom of the ion exchange resin bed 4 is 15% of the height of the ion exchange resin bed 4. The outlet water conductivity meter 6 is installed on the outlet pipe of the ion exchange resin bed 4. The electromagnetic flowmeter 2, the inlet water conductivity meter 3, the comparative conductivity meter 5 and the outlet water conductivity meter 6 are connected to the controller 1 through a signal transmission cable.

[0030] refer to Figure 2 , the specific working principle of the present invention is:

[0031] The influent flows into the ion exchange resin bed 4 through the electromagnetic flowmeter 2 and the influent conductivity meter 3. The influent flow rate q is measured by the electromagnetic flowmeter 2, and the influent conductivity κ1 is measured by the influent conductivity meter 3. The controller 1 calculates the ion concentration e1 in the influent according to the influent conductivity κ1.

[0032] The outlet water conductivity κ2 is measured by the outlet water conductivity meter 6, and the controller 1 calculates the ion concentration e2 in the outlet water according to the outlet water conductivity κ2;

[0033] Multiply the difference Δe between e1 and e2 by the flow rate q, and then integrate it with the running time t to obtain the ion load A entering the ion exchange resin bed 4, that is:

[0034] A=∫ t q×Δe

[0035] The maximum deionization capacity of the ion exchange resin is set to I. When A reaches I, it is determined that the resin is about to fail, and the controller 1 issues a resin failure warning.

[0036] The conductivity κ is measured and controlled by comparing it with the conductivity table 5. c , κ c The ratio of κ2 is used as the control parameter R:

[0037] R = κ c / κ2

[0038] During normal operation, the value of R is maintained at 1.0. When R deviates from 1.0 and the value of A does not reach 1, the controller 1 issues a resin failure warning and records the ion load A received by the ion exchange resin bed 4 at this time. i , and use A i Revision I, for detailed procedures, see Figure 2 .

Claims

1. A method for monitoring the deionization capacity of an ion exchange resin, characterized in that: A system for monitoring the deionization capacity of an ion exchange resin, the system comprising a controller (1), an electromagnetic flowmeter (2), an inlet water conductivity meter (3), an ion exchange resin bed (4) and an outlet water conductivity meter (6); The electromagnetic flowmeter (2) and the inlet water conductivity meter (3) are installed on the inlet water pipeline of the ion exchange resin bed (4), the outlet water conductivity meter (6) is installed on the outlet water pipeline of the ion exchange resin bed (4), and the electromagnetic flowmeter (2), the inlet water conductivity meter (3) and the outlet water conductivity meter (6) are connected to the controller (1); It also includes a comparative conductivity meter (5); the comparative conductivity meter (5) is installed on the side of the ion exchange resin bed (4), and the comparative conductivity meter (5) is connected to the controller (1); The following steps are involved: The influent water flows into the ion exchange resin bed (4) through the electromagnetic flowmeter (2) and the influent water conductivity meter (3), the influent water flow rate q is measured by the electromagnetic flowmeter (2), the influent water conductivity κ1 is measured by the influent water conductivity meter (3), and the controller (1) calculates the ion concentration e1 in the influent water according to the influent water conductivity κ1; The outlet water conductivity κ2 is measured by an outlet water conductivity meter (6), and the controller (1) calculates the ion concentration e2 in the outlet water according to the outlet water conductivity κ2; The difference △e between e1 and e2 is multiplied by the flow rate q, and then integrated with the running time t to obtain the ion load A entering the ion exchange resin bed (4), that is: A=∫ t q×△e The maximum deionization capacity of the ion exchange resin is set to I. When A reaches I, it is determined that the resin is about to fail, and the controller (1) issues a resin failure warning; The conductivity κ is measured by comparing with the conductivity meter (5) c , κ c The ratio of κ2 is used as the control parameter R: R=k c / k2 In normal operation, the value of R is maintained at 1.

0. When R deviates from 1.0 and the value of A does not reach 1, the controller (1) issues a resin failure warning and records the ion load A received by the ion exchange resin bed (4) at this time. i , and use A i Revision I.

2. The method for monitoring the deionization capacity of an ion exchange resin according to claim 1, characterized in that: The vertical distance from the conductivity meter (5) to the bottom of the ion exchange resin bed (4) is 15% of the height of the ion exchange resin bed (4).

3. The method for monitoring the deionization capacity of an ion exchange resin according to claim 1, characterized in that: The electromagnetic flowmeter (2), the inlet water conductivity meter (3), the comparison conductivity meter (5) and the outlet water conductivity meter (6) are connected to the controller (1) via a signal transmission cable.

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