Double-pressure-grade steam switching type deaerator system

Abstract

The invention relates to the technical field of deaerators, in particular to a double-pressure-grade steam switching type deaerator system which comprises a deaerator body and a double-pressure-grade steam inlet system of the deaerator body, and is characterized in that the double-pressure-grade steam inlet system is connected into two steam pipelines through the same flange connector; the two pipelines are respectively a low-pressure steam pipeline and a high-pressure steam pipeline. The two independent steam pipelines are designed, efficient utilization of energy is achieved through flexible steam supply control, and the problems that the operation cost is high, energy is wasted, and potential safety hazards are caused when high-pressure steam flows backwards to a low-pressure steam pipe network can be effectively solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of deaerators, in particular to a dual-pressure-grade steam switching type deaerator system. BACKGROUND

[0002] In the industrial fields of thermal power, petrochemical, and chemical engineering, deaerators are key water treatment equipment for ensuring the safe operation of boilers, heat exchangers, and other equipment. The core principle is to use steam heating to bring water to saturation temperature, and to remove dissolved oxygen and other gases in the water using Henry's Law to avoid oxygen corrosion of equipment. Currently, industrial deaerators mostly use single-pressure-grade steam inlet design, which is only suitable for steam sources with specific parameters (such as 0.3 MPa or 0.15 MPa), and the inlet system structure is simple.

[0003] However, in the actual production of large petrochemical enterprises, process devices produce multiple pressure grades of steam (such as 0.18 MPa low-pressure steam and 0.35 MPa medium-pressure steam), and the production of each grade of steam dynamically changes with production load fluctuations. The existing single-steam adaptive deaerator has two major problems: first, when the supply of preferentially used by-product steam is insufficient, additional purchased steam is needed to supplement, increasing operating costs; second, if the production of a certain grade of by-product steam is surplus and cannot be utilized by the deaerator, it will lead to energy waste. In addition, in some retrofit schemes that attempt to use dual steam, without effective anti-backflow structures, there is a risk of high-pressure steam flowing back into the low-pressure steam pipe network, affecting the safety of other steam-using equipment.

[0004] In existing public technologies, for example, the utility model patent with application number CN201921568978.3 discloses an energy-saving deaerator, and the utility model patent with application number CN202020865432.2 discloses a dual-steam deaerator. Although they mention the use of multiple steam sources, the former does not involve dual-pressure-grade switching design, and the latter does not solve the problem of high-pressure steam backflow, both of which cannot meet the needs of enterprises for flexible adaptation and safe use of by-product steam. Therefore, developing a deaerator that can adapt to dual-pressure-grade by-product steam, has anti-backflow function, and is flexible in switching has become a key requirement for improving industrial energy utilization. SUMMARY

[0005] To solve the above problems, the present application provides a dual-pressure-grade steam switching type deaerator system, which uses two independent steam pipelines and achieves efficient energy utilization through flexible steam supply control.

[0006] The technical solution adopted by the present application is as follows: The double-pressure-grade steam switching type deaerator system comprises a deaerator body and a double-pressure-grade steam inlet system.

[0007] Further, the rated processing flow of the deaerator body is 350-400 tons / hour, the operating pressure is 0.02-0.04 MPa, and the corresponding saturation temperature is 105-110 DEG C.

[0008] Further, the steam pressure of the low-pressure steam pipeline is 0.15-0.20 MPa, and an adjusting valve is connected in series on the pipeline.

[0009] Further, a check valve is connected in series on the low-pressure steam pipeline.

[0010] Further, the steam pressure of the high-pressure steam pipeline is 0.30-0.35 MPa, and an adjusting valve is connected in series on the pipeline.

[0011] Further, the double-pressure-grade steam inlet system can realize switching of low-pressure steam single operation, high-pressure steam single operation or combined operation of two steam.

[0012] Compared with the prior art, the present application has the following beneficial effects: 1. Significantly improve energy utilization efficiency and reduce operating cost: preferentially access and consume enterprise surplus by-product steam of 0.18 MPa, 0.35 MPa, etc., reduce dependence on external steam or high-cost steam sources, and directly reduce energy procurement and consumption cost.

[0013] 2. Ensure stable operation and strong adaptability to working conditions: support single, double and three operating mode switching, can adjust the inlet mode according to the real-time supply fluctuation of different pressure steam of the enterprise, avoid the fluctuation of deoxygenation effect caused by insufficient single steam supply, and ensure stable operation under the conventional flow of 350 tons / hour.

[0014] 3. Low reconstruction and maintenance cost and high safety: two steam share the same flange interface, no large-scale reconstruction of the deaerator body with a processing capacity of 400 tons / hour is needed, and the construction is simple; the check valve on the 0.18 MPa pipeline can effectively prevent high-pressure steam backflow and avoid pipeline network safety risk.

[0015] 4. Adapt to high load demand and improve equipment processing capacity: double steam combined operation can supply energy cooperatively, can match the maximum processing flow of 400 tons / hour of the deaerator, meet the deoxygenation demand of the enterprise in the production peak period, and improve the overall utilization rate of the equipment. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 A structure schematic diagram of a double-pressure-level steam switching type deaerator system is provided in the present application.

[0017] Wherein, the reference numerals: 1-deaerator body; 2-low pressure steam pipeline; 21-regulating valve I; 3-high pressure steam pipeline; 31-regulating valve II; 4-check valve. DETAILED DESCRIPTION

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced below. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor based on these drawings.

[0019] It should be noted that in the description of the present application, the terms "upper", "lower", "top", "bottom", "one side", "the other side", "left", "right" and the like indicate the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not mean that the device or element must have a particular orientation, be constructed and operated in a particular orientation.

[0020] Referring to the drawings Figure 1 The double-pressure-level steam switching type deaerator system provided in the present application comprises a deaerator body 1 and its raw water inlet and outlet system and a double-pressure-level steam inlet system; the double-pressure-level steam inlet system is connected to two steam pipelines through the same flange interface, which are a low pressure steam pipeline 2 and a high pressure steam pipeline 3.

[0021] Wherein, the rated treatment flow of the deaerator body 1 is 350-400 tons / hour, the operating pressure is 0.02-0.04 MPa, and the corresponding saturation temperature is 105-110℃.

[0022] The steam pressure of the low pressure steam pipeline 2 is 0.15-0.20 MPa, and the regulating valve I 21 and the check valve 4 are connected in series on the pipeline.

[0023] The steam pressure of the high pressure steam pipeline 3 is 0.30-0.35 MPa, and the regulating valve II 31 is connected in series on the pipeline.

[0024] The double-pressure-level steam inlet system can realize switching of low pressure steam single operation, high pressure steam single operation or two-way steam combined operation.

[0025] The system of the application is an independently designed external system, which is composed of two independent steam pipelines, a control assembly and a connecting interface, and is connected to the deaerator body 1 provided by the manufacturer through a single flange interface without any structural modification of the deaerator body 1.

[0026] The low-pressure steam pipeline 2 is adapted to a 0.18 MPa steam source, and a self-selected regulating valve and a check valve are connected in series on the pipeline. The regulating valve is used for accurately regulating the air intake, and the check valve is a key safety component, which can effectively prevent the reverse flow of high-pressure steam to the low-pressure steam pipeline network and avoid abnormal pressure of the pipeline network.

[0027] The high-pressure steam pipeline 3 is adapted to a 0.35 MPa steam source, and only a self-matched regulating valve is arranged on the pipeline, which can meet the steam supply demand under different deoxygenation loads by adjusting the valve opening.

[0028] Parameter adaptability: The system design parameters are accurately matched with the parameters of the deaerator body 1 provided by the manufacturer (rated flow 400 tons / hour, operating pressure 0.03 MPa, and saturation temperature 108℃), which ensures the high compatibility of steam supply and deoxygenation process demand.

[0029] The operation control logic of the application is as follows: Through the self-developed control logic, the system supports three flexible operation modes, which can be switched by opening and closing and adjusting the opening of the two-way pipeline regulating valve: 1. 0.18 MPa steam single supply mode: when the 0.18 MPa by-product steam is sufficient, close the regulating valve on the high-pressure steam pipeline 3, and only open the regulating valve on the low-pressure steam pipeline 2, and use the low-pressure steam to complete the deoxygenation heating.

[0030] 2. 0.35 MPa steam single supply mode: when the 0.35 MPa by-product steam is sufficient, close the low-pressure steam pipeline 2 regulating valve, and only open the regulating valve on the high-pressure steam pipeline 3, and switch to high-pressure steam supply.

[0031] 3. Dual-pressure steam combined supply mode: when the deoxygenation load reaches the rated value (400 tons / hour) or both kinds of steam are sufficient, open both regulating valves at the same time, and supply steam cooperatively to ensure the deoxygenation efficiency and stability.

[0032] The core difference between the application and the prior art is: Independence of the system: the prior art is mostly integrated design of the deaerator body and the air inlet system, and the modification needs to rely on the manufacturer; the system is an independently designed external system, which can directly adapt to the existing deaerator of the manufacturer, and has high flexibility.

[0033] Adaptability design: the existing intake system is mostly designed as "single pipeline-single pressure", which can only connect one steam source; the system can simultaneously adapt to 0.18MPa and 0.35MPa steam through the self-developed double pipeline design, effectively solving the problem of insufficient utilization of by-product steam.

[0034] Safety control: some existing double-steam-inlet schemes do not consider the risk of backflow; the system can eliminate the risk of high-pressure steam backflow from the structure by adding a check valve, and is more secure.

[0035] The core advantage of the present application is that: Self-controllability: the system is designed and developed by the site itself, without relying on equipment manufacturers, and can flexibly adjust parameters according to the actual situation of by-product steam on site, and has stronger adaptability.

[0036] Economic highlight: without replacing or modifying the existing manufacturer's deaerator, the system can be upgraded by external connection, greatly reducing equipment investment cost; at the same time, by-product steam is preferentially utilized, reducing the expenditure of purchased steam.

[0037] Strong practicality: convenient to install, simple to switch running mode, can directly connect to the existing steam pipe network and deaerator of the site, and can quickly improve energy utilization efficiency after being put into use.

[0038] Taking the deaeration system of a production workshop of Hengli Petrochemical (Dalian) New Material Technology Co., Ltd. as an application scenario, the double-pressure-grade steam switching type deaerator (rated processing flow 400 tons / hour, design running pressure 0.03MPa, corresponding saturation temperature 108℃) of the present application is verified, as follows: Experimental conditions: The supply of by-product steam of the enterprise is in a fluctuating state: in the morning, 0.18MPa steam is in surplus (hourly supply 45t), in the afternoon, 0.35MPa steam supply is sufficient (hourly supply 40t), and in the afternoon production peak period, the deaerator needs to run at full load (processing flow 400 tons / hour), at this time, 0.18MPa steam supply is 32t / h, and 0.35MPa steam supply is 28t / h. During the experiment, the running mode is switched according to the steam supply, the corresponding pipeline regulating valve is closed, and the check valve on the 0.18MPa pipeline remains in normal working condition.

[0039] Experimental parameters: Morning (0.18MPa alone): regulating valve opening 55%, steam consumption 43t / h, deaerator body pressure 0.03MPa, water temperature 108℃.

[0040] Afternoon (0.35MPa alone): regulating valve opening 40%, steam consumption 38t / h, deaerator body pressure 0.03MPa, water temperature 108℃.

[0041] Afternoon (double road joint operation): 0.18 MPa regulating valve opening 50%, 0.35 MPa regulating valve opening 45%, total steam consumption 58 t / h, deaerator body pressure 0.03 MPa, water temperature 108℃.

[0042] Experimental results: 1. Deaeration effect: The oxygen content of the outlet water in the three periods was 0.045 mg / L, 0.04 mg / L and 0.03 mg / L, respectively, all meeting the deaeration standard for industrial water.

[0043] 2. Running stability: The mode was switched flexibly according to the steam supply throughout the whole process, without shutdown, pressure fluctuation (≤±0.004 MPa) and water temperature abnormality, and the check valve did not appear high-pressure steam backflow phenomenon.

[0044] 3. Energy adaptability: From morning to afternoon, the device was operated relying on the by-product steam of the enterprise, without using external steam source, and under full load condition, the double-path steam could fully match the equipment processing demand.

[0045] 4. Modification adaptability: Since the two paths of steam shared the same flange interface, the equipment installation and modification only took 1.5 days, without changing the deaerator body structure, and adapting to the existing workshop deaeration system layout.

[0046] The details of the present application are well-known technology.

[0047] The above-described embodiments are merely preferred embodiments of the present application, and do not limit the scope of the present application. Without departing from the design spirit of the present application, various modifications and improvements to the technical solutions of the present application made by those skilled in the art shall fall within the protection scope of the present application as defined by the claims.

Claims

1. A dual pressure rating steam switch-type deaerator system comprising a deaerator body and its dual pressure rating steam intake system, characterized in that: The double-pressure-grade steam inlet system is connected to two steam pipelines, a low-pressure steam pipeline and a high-pressure steam pipeline, through the same flange interface.

2. A dual pressure rating steam-switched deaerator system as claimed in claim 1, wherein: The rated treatment flow of the deaerator body is 350-400 tons / hour, the operation pressure is 0.02-0.04 MPa, and the corresponding saturated temperature is 105-110 DEG C.

3. A dual pressure rating steam switchable deaerator system as claimed in claim 1, wherein: The steam pressure of the low-pressure steam pipeline is 0.15-0.20 MPa, and an adjusting valve is connected in series on the pipeline.

4. A dual pressure rating steam-switched deaerator system as claimed in claim 3, wherein: A check valve is connected in series on the low-pressure steam pipeline.

5. A dual pressure rating steam switchable deaerator system as claimed in claim 1, wherein: The steam pressure of the high-pressure steam pipeline is 0.30-0.35 MPa, and an adjusting valve is connected in series on the pipeline.

6. A dual pressure rating steam-switched deaerator system as claimed in claim 1, wherein: The double-pressure-grade steam inlet system can realize switching between low-pressure steam single operation, high-pressure steam single operation and combined operation of the two steam pipelines.

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