High-precision mercury standard gas generation system

Abstract

The utility model discloses a high-precision mercury standard gas generation system which comprises a carrier gas supply module, a mercury source evaporation module, a heat dilution mixing module, a sound speed small hole constant flow module and an intelligent control system, an outlet of the carrier gas supply module is communicated with an inlet of the mercury source evaporation module and an inlet of the heat dilution mixing module, an outlet of the mercury source evaporation module is communicated with an inlet of the sound speed small hole constant flow module, and an outlet of the sound speed small hole constant flow module is communicated with an inlet of the heat dilution mixing module; the intelligent control system is connected with the carrier gas supply module and the heat dilution mixing module. The system can generate mercury standard gas with high precision.

Description

Technical Field

[0001] This utility model belongs to the field of coal-fired air pollutant control technology, and relates to a high-precision mercury standard gas generation system. Background Technology

[0002] Because mercury standard gas cannot be stored in cylinders, unlike conventional CEMS systems, the continuous online mercury monitoring system (Hg-CEMS) requires periodic calibration of the system's accuracy via a mercury standard gas generation system.

[0003] Patent CN102692481B, entitled "Mercury Standard Gas Generator," comprises five units: an insulation unit with an inner liner and an insulation layer, separated by a vacuum insulation layer; a compensation gas inlet, a temperature measuring port, and a sampling port; a mercury standard gas source permeation unit located at the bottom of the inner liner of the insulation unit, including a quartz container and a slow-release membrane encapsulated at its opening; the slow-release membrane is either a quartz slow-release membrane or a ceramic slow-release membrane with a pore size range of 10-200 μm; a compensation gas purification unit located outside the insulation unit, including an adsorption column and control valves at both ends of the adsorption column, which is connected to the quartz container; a constant temperature control unit including a temperature controller, a constant temperature bath, and a circulating heating sleeve placed inside the inner liner; and a sampling unit equipped with a sampler that collects mercury standard gas from the insulation unit through the sampling port. The mercury standard gas generator employs a design of slow-inlet compensation gas and slow-release mercury-containing gas, enabling rapid system recovery. The purified clean compensation gas slowly enters the mercury standard source permeation unit through a capillary tube, mixes evenly with the mercury vapor evaporated at a constant temperature, and is then slowly released through a slow-release membrane. The mercury-containing gas that has passed through the slow-release membrane has basically reached saturation. This allows the container to be compensated and quickly restore balance after consuming the mercury standard gas, and also allows the concentration of the mercury standard gas to return to a constant level in a short time, which can be used for continuous calibration.

[0004] The above-described mercury standard gas generation technology is currently the mainstream technology for standard gas generation in laboratory / online mercury monitoring systems. Its principle is the saturated evaporation method of mercury. Mercury vapor is carried into the standard gas system by a carrier gas. Since the relationship between mercury vapor concentration and temperature can be accurately described by the Dumarey equation, the mercury vapor concentration can be adjusted by regulating the temperature. However, although the Dumarey equation can accurately calculate the saturated mercury vapor concentration in a closed container, the pressure and flow conditions of the subsequent pipelines can cause fluctuations in the carried mercury vapor concentration when the mercury vapor is carried by the carrier gas. This makes it difficult for the mercury standard gas generated by the saturated evaporation method to meet the requirements of high-precision calibration. Furthermore, the saturated mercury vapor generated by saturated evaporation will partially condense upon contact with subsequent pipelines, affecting the mercury concentration in the standard gas. Utility Model Content

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a high-precision mercury standard gas generation system that can generate mercury standard gas with high precision.

[0006] To achieve the above objectives, this utility model discloses a high-precision mercury standard gas generation system, including a carrier gas supply module, a mercury source evaporation module, a thermal dilution mixing module, a sonic orifice constant flow module, and an intelligent control system.

[0007] The outlet of the carrier gas supply module is connected to the inlet of the mercury source evaporation module and the inlet of the thermal dilution mixing module. The outlet of the mercury source evaporation module is connected to the inlet of the sonic orifice constant flow module. The outlet of the sonic orifice constant flow module is connected to the inlet of the thermal dilution mixing module.

[0008] The intelligent control system is connected to the carrier gas supply module and the thermal dilution and mixing module.

[0009] A further improvement of the high-precision mercury standard gas generating system described in this utility model is as follows:

[0010] Furthermore, the carrier gas supply module includes an inert gas source and a first pressure regulating valve, wherein the outlet of the inert gas source is connected to the inlet of the first pressure regulating valve and the inlet of the thermal dilution mixing module, the outlet of the first pressure regulating valve is connected to the inlet of the mercury source evaporation module, and the intelligent control system is connected to the first pressure regulating valve and the inert gas source.

[0011] Furthermore, the thermal dilution mixing module includes a thermal dilution ejector, a second pressure regulating valve, and a flow regulating valve. The outlet of the inert gas source is connected to the inlet of the thermal dilution ejector in sequence via the second pressure regulating valve and the flow regulating valve. The outlet of the sonic orifice constant flow module is connected to the inlet of the thermal dilution ejector. The intelligent control system is connected to the thermal dilution ejector, the second pressure regulating valve, and the flow regulating valve.

[0012] Furthermore, the sonic orifice in the sonic orifice constant current module is made of stainless steel.

[0013] Furthermore, the surface of the sonic pinhole is coated with an inert coating.

[0014] Furthermore, the thermal dilution ejector is made of stainless steel.

[0015] Furthermore, the surface of the thermally diluted ejector is provided with an inert coating.

[0016] Furthermore, the mercury source evaporation module is connected to the sonic orifice constant current module via a connecting pipe.

[0017] Furthermore, the connecting pipe is made of polytetrafluoroethylene / stainless steel with an inert coating.

[0018] This utility model has the following beneficial effects:

[0019] In practical operation, the high-precision mercury standard gas generation system described in this invention, under the regulation of the intelligent control system, allows inert carrier gas to enter the mercury source evaporation module at constant pressure. Under the constant pressure and constant flow action of the sonic orifice constant flow module, the influence of the pressure and flow state of the subsequent pipeline on the mercury vapor concentration is greatly eliminated. In addition, the mercury vapor is precisely diluted by the thermal dilution mixing module to obtain mercury standard gas with extremely high precision. It should be noted that this invention adopts high-precision mercury standard gas generation technology, which can stably generate high-precision mercury standard gas and overcome the problems of poor stability and the large influence of the standard gas concentration on the subsequent pipeline in traditional technologies. Attached Figure Description

[0020] The accompanying drawings, which form part of this specification, are used to provide a further understanding of this utility model. The illustrative embodiments and descriptions of this utility model are used to explain this utility model and do not constitute an undue limitation thereof. In the drawings:

[0021] Figure 1 This is a schematic diagram of the system of this utility model;

[0022] Among them, 1 is the carrier gas supply module, 11 is the inert gas source, 12 is the first pressure regulating valve, 2 is the mercury source evaporation module, 3 is the sonic orifice constant flow module, 4 is the thermal dilution mixing module, 41 is the second pressure regulating valve, 42 is the flow regulating valve, 43 is the thermal dilution ejector, 5 is the connecting pipe, and 6 is the intelligent control system. Detailed Implementation

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0024] In the description of this utility model, it should be understood that the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0025] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0026] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes such combinations. For example, A and / or B can represent three cases: A alone, A and B simultaneously, and B alone. Additionally, the character " / " in this invention generally indicates that the preceding and following objects have an "or" relationship.

[0027] It should be understood that although terms such as first, second, third, etc., may be used to describe preset ranges in the embodiments of this utility model, these preset ranges should not be limited to these terms. These terms are only used to distinguish the preset ranges from one another. For example, without departing from the scope of the embodiments of this utility model, the first preset range may also be referred to as the second preset range, and similarly, the second preset range may also be referred to as the first preset range.

[0028] Depending on the context, the word "if" as used here can be interpreted as "when," "when," "in response to determination," or "in response to detection." Similarly, depending on the context, the phrase "if determination" or "if detection (of the stated condition or event)" can be interpreted as "when determination," "in response to determination," "when detection (of the stated condition or event)," or "in response to detection (of the stated condition or event)."

[0029] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. The components of the embodiments of this utility model described and shown in the accompanying drawings can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this utility model provided in the accompanying drawings is not intended to limit the scope of the claimed utility model, but merely represents selected embodiments of the utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without inventive effort are within the scope of protection of this utility model.

[0030] The accompanying drawings show various structural schematic diagrams according to embodiments of the present invention. These drawings are not to scale, and some details have been enlarged and may have been omitted for clarity. The shapes of the various regions and layers shown in the drawings, as well as their relative sizes and positional relationships, are merely exemplary and may deviate from reality due to manufacturing tolerances or technical limitations. Furthermore, those skilled in the art can design regions / layers with different shapes, sizes, and relative positions as needed.

[0031] Example 1

[0032] refer to Figure 1 The high-precision mercury standard gas generation system of this utility model includes a carrier gas supply module 1, a mercury source evaporation module 2, a thermal dilution mixing module 4, a sonic orifice constant flow module 3, and an intelligent control system 6. The outlet of the carrier gas supply module 1 is connected to the inlet of the mercury source evaporation module 2 and the inlet of the thermal dilution mixing module 4. The outlet of the mercury source evaporation module 2 is connected to the inlet of the sonic orifice constant flow module 3. The outlet of the sonic orifice constant flow module 3 is connected to the inlet of the thermal dilution mixing module 4. The intelligent control system 6 is connected to the carrier gas supply module 1 and the thermal dilution mixing module 4.

[0033] During operation, under the control of the intelligent control system 6, the constant flow and constant pressure inert gas output by the carrier gas supply module 1 carries the mercury vapor generated by the mercury source evaporation module 2 and enters the sonic orifice constant flow module 3. Under the constant flow effect of the sonic orifice and the ejection effect of the thermal dilution ejector 43, the mercury-containing gas flow enters the thermal dilution ejector 43 at a constant flow rate and pressure and mixes and dilutes with the dilution gas to form the required high-precision mercury standard gas.

[0034] Example 2

[0035] refer to Figure 1 The high-precision mercury standard gas generation system of this utility model includes a carrier gas supply module 1, a mercury source evaporation module 2, a sonic orifice constant flow module 3, a thermal dilution mixing module 4, a connecting pipe 5, and an intelligent control system 6.

[0036] The outlet of the carrier gas supply module 1 is connected to the inlet of the mercury source evaporation module 2 and the inlet of the thermal dilution mixing module 4. The outlet of the mercury source evaporation module 2 is connected to the inlet of the sonic orifice constant flow module 3. The outlet of the sonic orifice constant flow module 3 is connected to the inlet of the thermal dilution mixing module 4.

[0037] In one embodiment of this utility model, the carrier gas supply module 1 includes an inert gas source 11 and a first pressure regulating valve 12. The outlet of the inert gas source 11 is connected to the inlet of the first pressure regulating valve 12 and the inlet of the thermal dilution mixing module 4. The outlet of the first pressure regulating valve 12 is connected to the inlet of the mercury source evaporation module 2. The intelligent control system 6 is connected to the control terminals of the carrier gas supply module 1, the mercury source evaporation module 2, and the thermal dilution mixing module 4.

[0038] As one embodiment of this utility model, the thermal dilution mixing module 4 includes a thermal dilution ejector 43, a second pressure regulating valve 41 and a flow regulating valve 42. The outlet of the inert gas source 11 is connected to the inlet of the thermal dilution ejector 43 via the second pressure regulating valve 41 and the flow regulating valve 42 in sequence. The outlet of the sonic orifice constant flow module 3 is connected to the inlet of the thermal dilution ejector 43.

[0039] In one embodiment of this utility model, the intelligent control system 6 is connected to the first pressure regulating valve 12, the second pressure regulating valve 41, the mercury source evaporation module 2, and the flow regulating valve 42.

[0040] As one embodiment of this utility model, it should be noted that the intelligent control system 6 is connected to the first pressure regulating valve 12 to ensure that the system is provided with the required constant pressure carrier gas.

[0041] As one embodiment of this utility model, it should be noted that the intelligent control system 6 is connected to the mercury source evaporation module 2, and the mercury source evaporation module 2 controls the evaporation rate of the mercury source by precisely adjusting the temperature.

[0042] As one embodiment of this utility model, the sonic orifice constant flow module 3 selects sonic orifices with different flow rates according to the standard gas flow requirements, and controls the flow rate of mercury-containing gas entering the thermal dilution mixing module 4 through the constant flow effect of the sonic orifices.

[0043] As one embodiment of this utility model, the sonic orifice in the sonic orifice constant current module 3 is made of stainless steel or other high-strength metals and alloys, and an inert coating such as quartz / polytetrafluoroethylene is added to its surface to reduce the adsorption of mercury.

[0044] As one embodiment of this utility model, when the thermal dilution mixing module 4 is working, under the ejection action of high-pressure inert gas, the constant flow of mercury-containing gas is mixed with inert dilution gas in the thermal dilution ejector 43 to produce the required mercury standard gas.

[0045] In one embodiment of this utility model, the thermal dilution ejector 43 is made of stainless steel or other high-strength metals and alloys, and an inert coating such as quartz / polytetrafluoroethylene is added to its surface to reduce the adsorption of mercury.

[0046] In one embodiment of this utility model, the connecting pipe 5 is made of polytetrafluoroethylene / stainless steel with an inert coating or other high-strength metal, and has a heating and heat preservation function to reduce the adsorption of mercury and the dilution and condensation of mercury in the pipeline.

[0047] As one embodiment of this utility model, the intelligent control system 6 can adjust the corresponding control parameters of the carrier gas supply module 1, the mercury source evaporation module 2 and the thermal dilution mixing module 4 according to the required mercury standard gas flow rate and concentration requirements, so as to generate the required high-precision mercury standard gas.

[0048] During operation, according to the set standard gas requirements, the constant flow and constant pressure inert gas output by the gas supply module 1 under the control of the intelligent control system 6 carries the mercury vapor generated by the mercury source evaporation module 2 into the sonic orifice constant flow module 3. Under the constant flow effect of the sonic orifice and the ejection effect of the thermal dilution ejector 43, the mercury-containing gas flow enters the thermal dilution ejector 43 at a constant flow rate and pressure to mix and dilute with the dilution gas to form the required high-precision mercury standard gas.

[0049] The module division in this embodiment is illustrative and represents only one logical functional division. In actual implementation, other division methods may be used. Furthermore, the functional modules in each embodiment of this application can be integrated into a single processor, exist as separate physical entities, or be integrated into a single module. The integrated modules described above can be implemented in hardware or as software functional modules.

[0050] Other embodiments of this utility model will readily conceive of by those skilled in the art upon consideration of the specification and disclosure thereof. This application is intended to cover any variations, uses, or adaptations of this utility model that follow the general principles of this utility model and include common knowledge or customary techniques in the art not disclosed herein. The specification and embodiments are to be considered exemplary only, and the true scope and spirit of this utility model are indicated by the following claims.

[0051] It should be understood that this invention is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this invention is limited only by the appended claims.

[0052] The above description is merely a preferred embodiment of the present utility model and does not constitute any limitation on the present utility model. Any simple modifications, alterations, or equivalent structural changes made to the above embodiments based on the technical essence of the present utility model shall still fall within the protection scope of the present utility model.

Claims

1. A high-precision mercury standard gas generation system, characterized in that, It includes a carrier gas supply module (1), a mercury source evaporation module (2), a thermal dilution mixing module (4), and a sonic orifice constant current module (3). The outlet of the carrier gas supply module (1) is connected to the inlet of the mercury source evaporation module (2) and the inlet of the thermal dilution mixing module (4). The outlet of the mercury source evaporation module (2) is connected to the inlet of the sonic orifice constant flow module (3). The outlet of the sonic orifice constant flow module (3) is connected to the inlet of the thermal dilution mixing module (4). It also includes an intelligent control system (6), which is connected to the carrier gas supply module (1) and the thermal dilution mixing module (4); The carrier gas supply module (1) includes an inert gas source (11) and a first pressure regulating valve (12). The outlet of the inert gas source (11) is connected to the inlet of the first pressure regulating valve (12) and the inlet of the thermal dilution mixing module (4). The outlet of the first pressure regulating valve (12) is connected to the inlet of the mercury source evaporation module (2). The intelligent control system (6) is connected to the first pressure regulating valve (12) and the inert gas source (11). The thermal dilution mixing module (4) includes a thermal dilution ejector (43), a second pressure regulating valve (41), and a flow regulating valve (42). The outlet of the inert gas source (11) is connected to the inlet of the thermal dilution ejector (43) in sequence through the second pressure regulating valve (41) and the flow regulating valve (42). The outlet of the sonic orifice constant flow module (3) is connected to the inlet of the thermal dilution ejector (43). The intelligent control system (6) is connected to the thermal dilution ejector (43), the second pressure regulating valve (41), and the flow regulating valve (42).

2. The high-precision mercury standard gas generating system according to claim 1, characterized in that, The sonic orifice in the sonic orifice constant current module (3) is made of stainless steel.

3. The high-precision mercury standard gas generating system according to claim 2, characterized in that, The surface of the sonic pinhole is coated with an inert coating.

4. The high-precision mercury standard gas generating system according to claim 1, characterized in that, The thermal dilution ejector (43) is made of stainless steel.

5. The high-precision mercury standard gas generating system according to claim 4, characterized in that, The surface of the thermally diluted ejector (43) is provided with an inert coating.

6. The high-precision mercury standard gas generating system according to claim 1, characterized in that, The mercury source evaporation module (2) is connected to the sonic orifice constant current module (3) via a connecting pipe (5).

7. The high-precision mercury standard gas generating system according to claim 6, characterized in that, The connecting pipe (5) is made of polytetrafluoroethylene / stainless steel with an inert coating.

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