A process for fine-treatment deep iron removal using a responsive external frequency conversion electromagnetic field.

Abstract

This invention relates to the field of water treatment technology and discloses a responsive external variable frequency electromagnetic field process for deep iron removal in fine treatment, comprising the following steps: S1, installation of an electromagnetic generator; S2, detection of iron ion concentration and hydrogen conductivity at the inlet; S3, frequency conversion treatment of condensate; S4, detection of total iron content and iron ion concentration at the outlet; S5, evaluation of iron removal effect in condensate. This invention, by adding an external variable frequency electromagnetic field to the condensate system, induces non-polar iron substances to undergo a chemical change, transforming them into polar iron particles and ions. This fully utilizes the separation function of the iron separator and the fine treatment unit, thereby achieving deep iron removal from the water-vapor system. The external electromagnetic field can be regularly adjusted according to the iron concentration to ensure sufficient induction of non-polar iron substances into polar and ionic states, avoiding excessive increase in iron solubility and ensuring the safe and stable operation of the water-vapor system.

Description

Technical Field

[0001] This invention relates to the field of water treatment technology, specifically a process for fine-treatment deep iron removal using a responsive external frequency conversion electromagnetic field. Background Technology

[0002] The stable operation of thermal power units is closely related to the stability of the power system, and the quality of steam and water in thermal power units is closely related to the unit's lifespan and operational stability. Therefore, ensuring a high pass rate for steam and water quality is a key factor in ensuring the success of thermal power units. Trace amounts of iron in steam and water are an important indicator of steam and water quality. When the iron content exceeds the standard, it will cause scale accumulation to grow too rapidly, leading to serious consequences such as boiler tube rupture and leaks. Therefore, the control and removal of iron ions in the steam and water system is extremely critical.

[0003] Units of 300MW and above are typically equipped with iron separators and fine treatment systems to remove impurities such as iron ions and iron scale from condensate, ensuring the pass rate of steam and water quality. Iron separators rely on magnetism to classify ferrous substances, while fine treatment systems remove iron ions through ion exchange. Non-magnetic particulate matter, including amorphous iron oxides and ordinary rust, is not easily removed in this process and tends to deposit on the inner side of the water-cooled walls, accelerating scale deposition and potentially leading to serious consequences such as boiler water-cooled wall tube leaks and tube ruptures. Summary of the Invention

[0004] The purpose of this invention is to provide a responsive external frequency conversion electromagnetic field process for fine-process deep iron removal, so as to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A process for fine-treatment deep iron removal using a responsive external frequency conversion electromagnetic field includes the following steps:

[0007] S1. Electromagnetic generator installation: Install the electromagnetic generator at the outlet of the condensate header and connect the electromagnetic generator to the external frequency converter power supply.

[0008] S2. Detection of iron ion concentration and hydrogen conductivity at the inlet: Sampling points are set up 1-3m from the inlet of the condensate header. The condensate flowing into the condensate header is sampled at the sampling points, and the iron ion concentration and hydrogen conductivity in the cooled condensate are detected to provide a true reflection of the changes in water quality flowing into the condensate header.

[0009] S3. Condensate Frequency Conversion Treatment: Connect the power electromagnetic generator to an external frequency converter. Based on the hydrogen conductivity and iron ion concentration indicators detected in step S2, adjust the power, current frequency, and peak voltage of the frequency converter. The frequency converter generates changing electric and magnetic fields to treat the condensate, inducing non-polar iron substances to transform into polar iron particles and iron ions, and further classifying the condensate. When the power is too high, exceeding the frequency required for the current iron ion content, it will increase the solubility of various iron forms, making it difficult to remove iron. At a constant frequency, it is not easy to generate magnetic iron substances. Therefore, the adjustable frequency converter can significantly improve the treatment effect of the subsequent iron separator and fine treatment unit. The condensate after frequency conversion treatment then enters the iron separator and fine treatment unit for further treatment, thereby removing the iron content in the condensate to a lower standard, achieving the purpose of deep iron removal from the condensate, obtaining better condensate quality, and thus slowing down the scaling rate of the boiler tubes such as the water-cooled wall, further protecting the thermal system.

[0010] S4. Detection of total iron content and iron ion concentration at the outlet: A sampling point is set at the outlet of the fine treatment unit. The condensate flowing out is sampled at the sampling point. The total iron content in the cooled condensate is detected by an inductively coupled plasma analyzer. The iron ion concentration in the cooled condensate is detected by spectrophotometry.

[0011] S5. Evaluation of iron removal effect in condensate: The iron removal effect of condensate is evaluated by comparing the total iron content and iron ion concentration in the condensate at the outlet of the fine treatment unit with the iron ion concentration and hydrogen conductivity in the condensate at the inlet of the condensate header.

[0012] As a further aspect of the present invention: in step S1, the electromagnetic generating device is a ring resistor; the inside of the ring resistor has a cross-sectional area of ​​1 cm². 2 The copper resistance wire is wrapped with an insulating layer.

[0013] As a further embodiment of the present invention: the length of the annular resistor wrapped around the outlet of the condensate header is 1.5 to 2 m, and the end of the winding is 2 to 3 m away from the outlet of the iron remover.

[0014] As a further aspect of the present invention: In step S3, the calculation formulas for adjusting the power supply, current frequency, and peak voltage of the frequency converter based on the hydrogen conductivity and iron ion concentration indicators are as follows:

[0015] P = 20 × D 0.6 ×C 0.5 (1),

[0016] f = 60 × D 0.5 ×C 0.4 (2),

[0017] U = 36 × D 0.5 ×C 0.5 (3),

[0018] In equations (1), (2), and (3) above, P is the power of the frequency converter, in W; f is the current frequency of the frequency converter, in Hz; U is the peak voltage of the frequency converter, in V; D is the hydrogen conductivity in the condensate, in uS / cm; and C is the iron ion concentration in the condensate, in ug / kg.

[0019] As a further aspect of the present invention: in step S4, before measuring the condensate sample using an inductively coupled plasma analyzer, the condensate sample is filtered using a 0.45 μm membrane; before measuring the condensate sample using spectrophotometry, the condensate sample is centrifuged at 12,000 rpm.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] This invention introduces an external variable-frequency electromagnetic field into the condensate system, inducing non-polar iron substances to undergo a chemical change, transforming them into polar iron particles and ions. This fully utilizes the separation function of the iron separator and the fine treatment unit, achieving deep removal of iron content from the water vapor system. Furthermore, the power, current frequency, and peak voltage of the external electromagnetic field are all adjustable. The applied electromagnetic field can be systematically changed according to the iron concentration to ensure sufficient induction of non-polar iron substances into polar and ionic states, avoiding excessive increase in iron solubility and ensuring the safe and stable operation of the water vapor system. Detailed Implementation

[0022] Example 1

[0023] A process for fine-treatment deep iron removal using a responsive external frequency conversion electromagnetic field includes the following steps:

[0024] S1. Electromagnetic Generator Installation: Install the electromagnetic generator at the outlet of the condensate drain header and connect it to an external frequency converter power supply. The electromagnetic generator is a toroidal resistor; the toroidal resistor has an internal cross-sectional area of ​​1 cm². 2 The copper resistance wire is wrapped with an insulation layer. The length of the ring resistor at the outlet of the condensate header is 1.8m, and the end of the winding is 2m away from the outlet of the iron separator.

[0025] S2. Detection of iron ion concentration and hydrogen conductivity at the inlet: A sampling point is set up 1m at the inlet of the condensate header. The condensate flowing into the condensate header is sampled at the sampling point, and the iron ion concentration and hydrogen conductivity of the cooled condensate are detected.

[0026] S3. Condensate frequency conversion treatment: Connect the power electromagnetic generator to an external frequency converter. Based on the hydrogen conductivity and iron ion concentration detected in step S2, adjust the power, current frequency, and peak voltage of the frequency converter. The frequency converter generates changing electric and magnetic fields to treat the condensate with frequency conversion, inducing non-polar iron substances to be converted into polar iron particles and iron ions, such as polar magnetite magnetic particles. The condensate is then classified from its depth. The frequency-treated condensate then enters the iron separator and fine treatment unit for further treatment.

[0027] S4. Detection of total iron content and iron ion concentration at the outlet: A sampling point is set at the outlet of the fine treatment unit. The condensate flowing out is sampled at the sampling point. After the condensate sample is filtered using a 0.45um membrane, the total iron content in the cooled condensate is detected by an inductively coupled plasma analyzer. After the condensate sample is centrifuged at 12000rpm, the iron ion concentration in the cooled condensate is detected by spectrophotometry.

[0028] S5. Evaluation of iron removal effect of condensate: The iron removal effect of condensate is evaluated by comparing the total iron content and iron ion concentration in the condensate at the outlet of the fine treatment unit with the iron ion concentration and hydrogen conductivity in the condensate at the inlet of the condensate header.

[0029] The formulas for calculating the power, current frequency, and peak voltage of a frequency converter are as follows:

[0030] P = 20 × D 0.6 ×C 0.5 (1),

[0031] f = 60 × D 0.5 ×C 0.4 (2),

[0032] U = 36 × D 0.5 ×C 0.5 (3),

[0033] In equations (1), (2), and (3) above, P is the power of the frequency converter, in W; f is the current frequency of the frequency converter, in Hz; U is the peak voltage of the frequency converter, in V; D is the hydrogen conductivity in the condensate, in uS / cm; and C is the iron ion concentration in the condensate, in ug / kg.

[0034] Taking the condensate system of Unit 6 at Huaneng Jiaxiang Power Plant as the treatment target, an electromagnetic generator was installed at the outlet of the condensate header of Unit 6 to measure the average iron content (unit: ppb) and the scale accumulation rate on the fire side (unit: g / (a*m)). 2 )) and back-side scale accumulation rate (unit: g / (a*m)2 )) and record them in Table 1 below.

[0035] Table 1

[0036]

[0037] Table 1 above shows that, compared with before deep iron removal, the average iron content, the rate of scale accumulation on the fire-facing side, and the rate of scale accumulation on the back-fire side of the condensate system of Unit 6 of Huaneng Jiaxiang Power Plant all decreased significantly after deep iron removal.

[0038] Example 2

[0039] A process for fine-treatment deep iron removal using a responsive external frequency conversion electromagnetic field includes the following steps:

[0040] S1. Electromagnetic Generator Installation: Install the electromagnetic generator at the outlet of the condensate drain header and connect it to an external frequency converter power supply. The electromagnetic generator is a toroidal resistor; the toroidal resistor has an internal cross-sectional area of ​​1 cm². 2 The copper resistance wire is wrapped with an insulation layer. The length of the ring resistor at the outlet of the condensate header is 2m, and the end of the winding is 3m away from the outlet of the iron separator.

[0041] S2. Detection of iron ion concentration and hydrogen conductivity at the inlet: A sampling point is set up 2m at the inlet of the condensate header. The condensate flowing into the condensate header is sampled at the sampling point, and the iron ion concentration and hydrogen conductivity of the cooled condensate are detected.

[0042] S3. Condensate frequency conversion treatment: Connect the power electromagnetic generator to an external frequency converter. Based on the hydrogen conductivity and iron ion concentration detected in step S2, adjust the power, current frequency, and peak voltage of the frequency converter. The frequency converter generates changing electric and magnetic fields to treat the condensate by frequency conversion, inducing non-polar iron substances to be converted into polar iron particles and iron ions. The condensate is then classified from deep within the condensate. The condensate after frequency conversion treatment then enters the iron separator and fine treatment unit for further treatment.

[0043] S4. Detection of total iron content and iron ion concentration at the outlet: A sampling point is set at the outlet of the fine treatment unit. The condensate flowing out is sampled at the sampling point. After the condensate sample is filtered using a 0.45um membrane, the total iron content in the cooled condensate is detected by an inductively coupled plasma analyzer. After the condensate sample is centrifuged at 12000rpm, the iron ion concentration in the cooled condensate is detected by spectrophotometry.

[0044] S5. Evaluation of iron removal effect of condensate: The iron removal effect of condensate is evaluated by comparing the total iron content and iron ion concentration in the condensate at the outlet of the fine treatment unit with the iron ion concentration and hydrogen conductivity in the condensate at the inlet of the condensate header.

[0045] Variable frequency power supply parameter control: Same as in Example 1.

[0046] Taking the condensate system of Unit 7 at Huaneng Laiwu Power Plant as the treatment target, an electromagnetic generator was installed at the outlet of the condensate header of Unit 7 to measure the average iron content (unit: ppb) and the scale accumulation rate on the fire side (unit: g / (a*m)). 2 )) and back-side scale accumulation rate (unit: g / (a*m) 2 )) and record them in Table 2 below.

[0047] Table 2

[0048]

[0049] Table 2 above shows that, compared with before deep iron removal, the average iron content, the rate of scale accumulation on the fire-facing side, and the rate of scale accumulation on the back-fire side of the condensate system of Unit 7 of Huaneng Laiwu Power Plant all decreased significantly after deep iron removal.

[0050] Example 3

[0051] A process for fine-treatment deep iron removal using a responsive external frequency conversion electromagnetic field includes the following steps:

[0052] S1. Electromagnetic Generator Installation: Install the electromagnetic generator at the outlet of the condensate drain header and connect it to an external frequency converter power supply. The electromagnetic generator is a toroidal resistor; the toroidal resistor has an internal cross-sectional area of ​​1 cm². 2 The copper resistance wire is wrapped with an insulation layer. The length of the ring resistor at the outlet of the condensate header is 1.5m, and the end of the winding is 2m away from the outlet of the iron separator.

[0053] S2. Detection of iron ion concentration and hydrogen conductivity at the inlet: A sampling point is set up 3m at the inlet of the condensate header. The condensate flowing into the condensate header is sampled at the sampling point, and the iron ion concentration and hydrogen conductivity of the cooled condensate are detected.

[0054] S3. Condensate frequency conversion treatment: Connect the power electromagnetic generator to an external frequency converter. Based on the hydrogen conductivity and iron ion concentration detected in step S2, adjust the power, current frequency, and peak voltage of the frequency converter. The frequency converter generates changing electric and magnetic fields to treat the condensate by frequency conversion, inducing non-polar iron substances to be converted into polar iron particles and iron ions. The condensate is then classified from deep within the condensate. The condensate after frequency conversion treatment then enters the iron separator and fine treatment unit for further treatment.

[0055] S4. Detection of total iron content and iron ion concentration at the outlet: A sampling point is set at the outlet of the fine treatment unit. The condensate flowing out is sampled at the sampling point. After the condensate sample is filtered using a 0.45um membrane, the total iron content in the cooled condensate is detected by an inductively coupled plasma analyzer. After the condensate sample is centrifuged at 12000rpm, the iron ion concentration in the cooled condensate is detected by spectrophotometry.

[0056] S5. Evaluation of iron removal effect of condensate: The iron removal effect of condensate is evaluated by comparing the total iron content and iron ion concentration in the condensate at the outlet of the fine treatment unit with the iron ion concentration and hydrogen conductivity in the condensate at the inlet of the condensate header.

[0057] Variable frequency power supply parameter control: Same as in Example 1.

[0058] Taking the condensate system of Unit 6 at Huadian Zouxian Power Plant as the treatment target, an electromagnetic generator was installed at the outlet of the condensate header of Unit 6 to measure the average iron content (unit: ppb) and the scale accumulation rate on the fire side (unit: g / (a*m)). 2 )) and back-side scale accumulation rate (unit: g / (a*m) 2 )) and record them in Table 3 below.

[0059] Table 3

[0060]

[0061] Table 3 above shows that, compared with before deep iron removal, the average iron content, the rate of scale accumulation on the fire side, and the rate of scale accumulation on the back side of the condensate system of Unit 6 of Huadian Zouxian Power Plant all decreased significantly after deep iron removal.

[0062] Example 4

[0063] A process for fine-treatment deep iron removal using a responsive external frequency conversion electromagnetic field includes the following steps:

[0064] S1. Electromagnetic Generator Installation: Install the electromagnetic generator at the outlet of the condensate drain header and connect it to an external frequency converter power supply. The electromagnetic generator is a toroidal resistor; the toroidal resistor has an internal cross-sectional area of ​​1 cm². 2 The copper resistance wire is wrapped with an insulation layer. The length of the ring resistor at the outlet of the condensate header is 1.7m, and the end of the winding is 2.4m away from the outlet of the iron separator.

[0065] S2. Detection of iron ion concentration and hydrogen conductivity at the inlet: A sampling point is set at 1.5m at the inlet of the condensate header. The condensate flowing into the condensate header is sampled at the sampling point, and the iron ion concentration and hydrogen conductivity of the cooled condensate are detected.

[0066] S3. Condensate frequency conversion treatment: Connect the power electromagnetic generator to an external frequency converter. Based on the hydrogen conductivity and iron ion concentration detected in step S2, adjust the power, current frequency, and peak voltage of the frequency converter. The frequency converter generates changing electric and magnetic fields to treat the condensate by frequency conversion, inducing non-polar iron substances to be converted into polar iron particles and iron ions. The condensate is then classified from deep within the condensate. The condensate after frequency conversion treatment then enters the iron separator and fine treatment unit for further treatment.

[0067] S4. Detection of total iron content and iron ion concentration at the outlet: A sampling point is set at the outlet of the fine treatment unit. The condensate flowing out is sampled at the sampling point. After the condensate sample is filtered using a 0.45um membrane, the total iron content in the cooled condensate is detected by an inductively coupled plasma analyzer. After the condensate sample is centrifuged at 12000rpm, the iron ion concentration in the cooled condensate is detected by spectrophotometry.

[0068] S5. Evaluation of iron removal effect of condensate: The iron removal effect of condensate is evaluated by comparing the total iron content and iron ion concentration in the condensate at the outlet of the fine treatment unit with the iron ion concentration and hydrogen conductivity in the condensate at the inlet of the condensate header.

[0069] Variable frequency power supply parameter control: Same as in Example 1.

[0070] Taking the condensate system of Unit 3 at Huadian Zibo Power Plant as the treatment target, an electromagnetic generator was installed at the outlet of the condensate header of Unit 3 to measure the average iron content (unit: ppb) and the scale accumulation rate on the fire side (unit: g / (a*m)). 2 )) and back-side scale accumulation rate (unit: g / (a*m) 2 )) and record them in Table 4 below.

[0071] Table 4

[0072]

[0073] Table 4 above shows that, compared with before deep iron removal, the average iron content, the rate of scale accumulation on the fire-facing side, and the rate of scale accumulation on the back-fire side of the condensate system of Unit 3 of Huadian Zibo Power Plant all decreased significantly after deep iron removal.

[0074] Therefore, it can be concluded that the present invention deeply removes iron impurities from condensate by establishing an external electromagnetic field treatment process. This process is based on an external electromagnetic field to induce non-magnetic iron substances in condensate to transform into strongly magnetic iron substances.

[0075] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A process for fine-treatment deep iron removal using a responsive external frequency conversion electromagnetic field, characterized in that, Includes the following steps: S1. Electromagnetic generator installation: Install the electromagnetic generator at the outlet of the condensate header and connect the electromagnetic generator to the external frequency converter power supply. S2. Detection of iron ion concentration and hydrogen conductivity at the inlet: Sampling points are set up 1-3m from the inlet of the condensate header. The condensate flowing into the condensate header is sampled at the sampling points, and the iron ion concentration and hydrogen conductivity of the cooled condensate are detected. S3. Condensate frequency conversion treatment: Connect the power electromagnetic generator to an external frequency converter. Based on the hydrogen conductivity and iron ion concentration detected in step S2, adjust the power, current frequency, and peak voltage of the frequency converter. The frequency converter generates changing electric and magnetic fields to treat the condensate. This induces non-polar iron substances to be converted into polar iron particles and iron ions. Under the action of the external magnetic field, the condensate is deeply separated, thus achieving the purpose of deeply removing iron impurities from the condensate. The condensate after frequency conversion treatment then enters the iron separator and fine treatment unit for further treatment. S4. Detection of total iron content and iron ion concentration at the outlet: A sampling point is set at the outlet of the fine treatment unit. The condensate flowing out is sampled at the sampling point. The total iron content in the cooled condensate is detected by an inductively coupled plasma analyzer. The iron ion concentration in the cooled condensate is detected by spectrophotometry. Before measuring the condensate sample using an inductively coupled plasma analyzer, the condensate sample was filtered using a 0.45 μm membrane; before measuring the condensate sample using spectrophotometry, the condensate sample was centrifuged at 12,000 rpm. S5. Evaluation of iron removal effect in condensate: The iron removal effect of condensate is evaluated by comparing the total iron content and iron ion concentration in the condensate at the outlet of the fine treatment unit with the iron ion concentration and hydrogen conductivity in the condensate at the inlet of the condensate header.

2. The process for fine-treatment deep iron removal using a responsive external frequency conversion electromagnetic field according to claim 1, characterized in that, In step S1, the electromagnetic generator is a ring resistor; the ring resistor has an internal cross-sectional area of ​​1 cm². 2 The copper resistance wire is wrapped with an insulating layer.

3. The process for fine-treatment deep iron removal using a responsive external frequency conversion electromagnetic field according to claim 2, characterized in that, The length of the ring resistor wrapped around the outlet of the condensate header is 1.5 to 2 m, and the end of the winding is 2 to 3 m away from the outlet of the iron remover.

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