Control system of open type ship tail gas desulfurization device

Abstract

The invention relates to a control system of an open ship tail gas desulfurization device, and belongs to the technical field of ship tail gas desulfurization. Wherein the seawater supply module is used for introducing seawater into the open type ship tail gas desulfurization device for desulfurization and inputting the seawater into the desulfurization device; the tail gas exhaust-in module is used for exhausting ship tail gas into the desulfurization device; the data acquisition module is used for acquiring operation parameters of the desulfurization device; the self-adaptive adjusting module is used for dynamically adjusting the adding amount of the desulfurizing agent according to the operation parameters; the catalytic reduction module is used for controlling the system temperature and the ammonia injection amount to optimally control tail gas; the tail gas discharge module is used for discharging the gas after the desulfurization reaction of the desulfurization device into the catalytic reduction module, and discharging the tail gas after optimization control into the atmosphere through the catalytic reduction module; and the liquid discharge module is used for performing desulfurization reaction on the received solution in the desulfurization tower and discharging the solution into the sea. The desulfurization efficiency is improved, and the device can adapt to changes under different working conditions.

Description

Technical Field

[0001] The invention belongs to the technical field of ship exhaust gas desulfurization, and in particular relates to a control system of an open ship exhaust gas desulfurization device. Background Art

[0002] The open exhaust gas desulfurization device for ships is a system that uses seawater to clean and desulfurize exhaust gas. This device reduces sulfur oxide emissions by contacting the exhaust gas with seawater and using the alkaline substances in the seawater to neutralize the acidic components in the exhaust gas. According to the design specifications for ship exhaust gas treatment systems issued by China Classification Society, the open exhaust gas cleaning system refers to the direct use of seawater to clean and desulfurize the exhaust gas. The washing water after desulfurization is treated by a special water treatment device and is directly discharged overboard after meeting the emission standards. The equipment of the open desulfurization device is large in size, difficult to arrange, and the equipment is prone to corrosion, which to a certain extent affects the effect of ship exhaust gas treatment. In addition, the washing process has a large pressure drop, which affects the fuel economy of the ship, and is heavily dependent on fresh water, which makes the energy consumption matching of the sulfur control equipment a bottleneck when the load changes in complex multi-operating conditions; and the washing water discharged from the open desulfurization device needs to be treated by a special water treatment device before it can be discharged overboard, which poses a challenge to the acid-base buffering capacity of seawater, which may lead to a decrease in absorption efficiency and increase the risk of excessive exhaust gas. Summary of the invention

[0003] In order to solve the above problems existing in the prior art, the present invention provides a control system for an open ship exhaust gas desulfurization device. The purpose of the present invention can be achieved through the following technical solutions: A control system for an open ship exhaust gas desulfurization device, comprising: Seawater supply module, exhaust gas discharge module, adaptive adjustment module, data acquisition module, catalytic reduction module, exhaust gas emission module, and drainage module; The seawater supply module is used to introduce seawater into the open ship exhaust gas desulfurization device for desulfurization, and the seawater is input into the desulfurization device from the upper inlet of the desulfurization device through a circulating water pump; The exhaust gas discharge module discharges the ship exhaust gas into the desulfurization device through the exhaust gas inlet when the desulfurization device is started; The data acquisition module is used to obtain the operating parameters of the desulfurization device; The adaptive adjustment module is used to dynamically adjust the amount of desulfurizer added according to the operating parameters; The catalytic reduction module is used to control the system temperature and ammonia injection amount to optimize the exhaust gas; The tail gas emission module is used to discharge the gas after the desulfurization reaction in the desulfurization device into the catalytic reduction module, and discharge the optimized and controlled tail gas into the atmosphere through the catalytic reduction module; The liquid discharge module is used to discharge the solution received in the desulfurization tower after desulfurization reaction is neutralized by seawater supplied by the seawater supply module into the sea.

[0004] Specifically, the seawater supply module is also connected to a slurry pool, which is used to mix seawater and limestone powder to form limestone slurry, and to send the limestone slurry to the top of the desulfurization tower of the desulfurization device through a slurry circulation pump and a concentration meter for spraying reaction. The concentration meter is used to measure the slurry concentration in the slurry circulation pipeline and send the slurry concentration signal to the adaptive adjustment module.

[0005] Specifically, the operating parameters include the pH value of the absorption tower and the concentration of the desulfurizer; the addition amount of the desulfurizer and the limestone slurry is dynamically adjusted according to the operating parameters by the adaptive adjustment module.

[0006] Specifically, the dynamic adjustment method is: The adaptive adjustment module sets the target values ​​of sulfur oxide concentration in the tail gas and pH value of the absorption tower, constructs a PID controller according to the error between the real-time measured values ​​of the desulfurizer concentration and pH value of the absorption tower and the target values, converts the output signal of the PID controller into the valve opening of the desulfurizer addition pump and the limestone slurry addition pump, and monitors the changes of the desulfurizer concentration, sulfur oxide concentration in the tail gas and pH value of the absorption tower in real time, and feeds back the change information to the PID controller for continuous optimization; The PID parameters of the PID controller include a proportional coefficient, an integral coefficient, and a differential coefficient; the proportional coefficient is adjusted to determine the sensitivity of the proportional control to the error; the integral coefficient is adjusted to determine the sensitivity of the integral control to the error accumulation; the differential coefficient is adjusted to determine the sensitivity of the differential control to the error change rate, and the PID algorithm is implemented. The formula of the PID control algorithm is as follows: ; Among them, Control Signal is the control signal, K p , K i , K d are the proportional coefficient, integral coefficient, and differential coefficient respectively. e(t) is the error at time t. is the integral of the error, is the rate of change of error.

[0007] Specifically, the catalytic reduction module converts SO2 in sulfur oxides into harmless SO3 through a catalyst at a preset system temperature, and reacts with ammonia to generate ammonium sulfate. The catalyst system of the catalytic reduction module includes a catalyst, a catalyst carrier, and a co-catalyst. The catalyst is vanadium pentoxide, the catalyst carrier is silicon dioxide, and the co-catalyst is potassium sulfate. The catalyst, catalyst carrier, and co-catalyst are introduced into the catalytic reduction module in solid form, and a catalytic oxidation reaction is carried out in the melt on the surface of the catalyst carrier.

[0008] Specifically, the desulfurizing agent consists of seawater and sodium hydroxide solution.

[0009] Specifically, the exhaust emission module uses an activated carbon adsorption tower to further remove sulfur oxides in the exhaust gas.

[0010] The beneficial effects of the present invention are: By setting up an adaptive adjustment module, continuous detection of the sulfide concentration in the ship's exhaust gas is achieved, and the injection amount of the desulfurizer is automatically adjusted accordingly. The operating conditions can be dynamically adjusted according to the desulfurization effect, ensuring the accuracy of the desulfurization process and the satisfaction of the exhaust emission standards; after reducing most of the sulfur oxides in the open desulfurization device, the integrated catalytic reduction module selectively catalytically reduces the remaining sulfur oxides in the exhaust gas, further reducing sulfur oxide emissions; by dynamically controlling the pH value of the absorption tower and the desulfurizer concentration in parallel, the wet desulfurization method is operated in the open desulfurization device to further improve the removal efficiency of sulfur oxides. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to facilitate understanding by those skilled in the art, the present invention is further described below with reference to the accompanying drawings.

[0012] Figure 1 The present invention is a schematic structural diagram of a control system of an open ship exhaust gas desulfurization device.

[0013] Figure 2 A schematic diagram of a control system of an open ship exhaust gas desulfurization device according to the present invention. DETAILED DESCRIPTION

[0014] In order to further explain the technical means and effects adopted by the present invention to achieve the predetermined invention purpose, the specific implementation methods, structures, features and effects of the present invention are described in detail below in conjunction with the accompanying drawings and preferred embodiments.

[0015] See also Figure 1-2 , a control system for an open ship exhaust gas desulfurization device, comprising: Seawater supply module, exhaust gas discharge module, adaptive adjustment module, data acquisition module, catalytic reduction module, exhaust gas emission module, and drainage module; The seawater supply module is used to introduce seawater into the open ship exhaust gas desulfurization device for desulfurization, and the seawater is input into the desulfurization device from the upper inlet of the desulfurization device through a circulating water pump; The exhaust gas discharge module discharges the ship exhaust gas into the desulfurization device through the exhaust gas inlet when the desulfurization device is started; The data acquisition module is used to obtain the operating parameters of the desulfurization device; The adaptive adjustment module is used to dynamically adjust the amount of desulfurizer added according to the operating parameters; The catalytic reduction module is used to control the system temperature and ammonia injection amount to optimize the exhaust gas; The tail gas emission module is used to discharge the gas after the desulfurization reaction in the desulfurization device into the catalytic reduction module, and discharge the optimized and controlled tail gas into the atmosphere through the catalytic reduction module; The liquid discharge module is used to discharge the solution received in the desulfurization tower after desulfurization reaction is neutralized by seawater supplied by the seawater supply module into the sea.

[0016] Specifically, the seawater supply module is also connected to a slurry pool, which is used to mix seawater and limestone powder to form limestone slurry, and to send the limestone slurry to the top of the desulfurization tower of the desulfurization device through a slurry circulation pump and a concentration meter for spraying reaction. The concentration meter is used to measure the slurry concentration in the slurry circulation pipeline and send the slurry concentration signal to the adaptive adjustment module.

[0017] Specifically, the operating parameters include the pH value of the absorption tower and the concentration of the desulfurizer; the addition amount of the desulfurizer and the limestone slurry is dynamically adjusted according to the operating parameters by the adaptive adjustment module.

[0018] Specifically, the dynamic adjustment method is: The adaptive adjustment module sets the target values ​​of sulfur oxide concentration in the tail gas and pH value of the absorption tower, constructs a PID controller according to the error between the real-time measured values ​​of the desulfurizer concentration and pH value of the absorption tower and the target values, converts the output signal of the PID controller into the valve opening of the desulfurizer addition pump and the limestone slurry addition pump, and monitors the changes of the desulfurizer concentration, sulfur oxide concentration in the tail gas and pH value of the absorption tower in real time, and feeds back the change information to the PID controller for continuous optimization; The PID parameters of the PID controller include a proportional coefficient, an integral coefficient, and a differential coefficient; the proportional coefficient is adjusted to determine the sensitivity of the proportional control to the error; the integral coefficient is adjusted to determine the sensitivity of the integral control to the error accumulation; the differential coefficient is adjusted to determine the sensitivity of the differential control to the error change rate, and the PID algorithm is implemented. The formula of the PID control algorithm is as follows: ; Among them, Control Signal is the control signal, K p , K i , K d are the proportional coefficient, integral coefficient, and differential coefficient respectively. e(t) is the error at time t. is the integral of the error, is the rate of change of error.

[0019] Specifically, the catalytic reduction module converts SO2 in sulfur oxides into harmless SO3 through a catalyst at a preset system temperature, and reacts with ammonia to generate ammonium sulfate. The catalyst system of the catalytic reduction module includes a catalyst, a catalyst carrier, and a co-catalyst. The catalyst is vanadium pentoxide, the catalyst carrier is silicon dioxide, and the co-catalyst is potassium sulfate. The catalyst, catalyst carrier, and co-catalyst are introduced into the catalytic reduction module in solid form, and a catalytic oxidation reaction is carried out in the melt on the surface of the catalyst carrier.

[0020] Specifically, the desulfurizing agent consists of seawater and sodium hydroxide solution.

[0021] Specifically, the exhaust emission module uses an activated carbon adsorption tower to further remove sulfur oxides in the exhaust gas.

[0022] In this embodiment, the limestone slurry at the bottom of the absorption tower is sent to the top of the desulfurization tower of the open desulfurization device through a concentration meter by a parallel running slurry circulation pump for spraying reaction; the desulfurization washing tower adopts a U-shaped tower, and when the desulfurization system is not required to work, the exhaust gas is directly discharged through the bypass pipeline; the adaptive adjustment module sets the target value and the measured actual value, and the target value of the SO2 concentration in the tail gas is set according to environmental protection regulations and desulfurization efficiency requirements. The actual value is determined by measuring the SO2 concentration in the tail gas in real time by equipment such as an exhaust gas analyzer; the difference between the target value and the actual value is calculated, that is, the error = target value-actual value. The proportional control part in the PID controller adjusts the addition rate of the desulfurizer according to the current error size. The larger the error, the larger the adjustment amplitude; the integral control part takes into account the past error accumulation and is used to eliminate static errors, that is, errors accumulated over a long period of time; the differential control part predicts the future trend of the error and adjusts the addition rate of the desulfurizer according to the rate of change of the error to reduce overshoot and oscillation. Control the desulfurizer addition rate, and convert the output signal of the PID controller into the speed of the desulfurizer addition pump or the valve opening through the actuator to adjust the desulfurizer addition rate. In the feedback adjustment stage, the changes in the desulfurizer concentration and the SO2 concentration in the tail gas are monitored in real time, and this information is fed back to the PID controller for further adjustment; according to the actual response of the system, the PID parameters are continuously adjusted to obtain the best control system performance. Ensure that the PID control system can remain stable under various working conditions to avoid system oscillation or instability.

[0023] The computer storage medium of the embodiment of the present invention may adopt any combination of one or more computer-readable media. The computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. The computer-readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or device, or any combination of the above. More specific examples (non-exhaustive list) of computer-readable storage media include: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this document, a computer-readable storage medium may be any tangible medium containing or storing a program that may be used by or in combination with an instruction execution system, device or device.

[0024] Computer-readable signal media may include data signals propagated in baseband or as part of a carrier wave, which carry computer-readable program code. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. Computer-readable signal media may also be any computer-readable medium other than a computer-readable storage medium, which may send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0025] The program code included on the computer readable medium can be transmitted with any appropriate medium, including but not limited to wireless, electric wire, optical cable, RF, etc., or any suitable combination of the above. The computer program code for performing the operation of the present invention can be written in one or more programming languages ​​or their combinations, and the programming language includes object-oriented programming languages-such as Java, Smalltalk, C++, and also includes conventional procedural programming languages-such as "C" language or similar programming languages. The program code can be executed completely on the user's computer, partially on the user's computer, as an independent software package, partially on the user's computer and partially on the remote computer, or completely on the remote computer or server. In the case of a remote computer, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or it can be connected to an external computer (for example, using an Internet service provider to connect through the Internet).

[0026] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technical personnel in this field can make some changes or modify the technical contents disclosed above into equivalent embodiments without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A control system for an open ship exhaust gas desulfurization device, characterized in that: include: Seawater supply module, exhaust gas discharge module, adaptive adjustment module, data acquisition module, catalytic reduction module, exhaust gas emission module, and drainage module; The seawater supply module is used to introduce seawater into the open ship exhaust gas desulfurization device for desulfurization, and the seawater is input into the desulfurization device from the upper inlet of the desulfurization device through a circulating water pump; The exhaust gas discharge module discharges the ship exhaust gas into the desulfurization device through the exhaust gas inlet when the desulfurization device is started; The data acquisition module is used to obtain the operating parameters of the desulfurization device; The adaptive adjustment module is used to dynamically adjust the amount of desulfurizer added according to the operating parameters; The catalytic reduction module is used to control the system temperature and ammonia injection amount to optimize the exhaust gas; The tail gas emission module is used to discharge the gas after the desulfurization reaction in the desulfurization device into the catalytic reduction module, and discharge the optimized and controlled tail gas into the atmosphere through the catalytic reduction module; The liquid discharge module is used to discharge the solution received in the desulfurization tower after desulfurization reaction is neutralized by seawater supplied by the seawater supply module into the sea.

2. The system according to claim 1, characterized in that The seawater supply module is also connected to a slurry pool, which is used to mix seawater and limestone powder to form limestone slurry, and to send the limestone slurry to the top of the desulfurization tower of the desulfurization device through a slurry circulation pump and a concentration meter for spraying reaction. The concentration meter is used to measure the slurry concentration in the slurry circulation pipeline and send the slurry concentration signal to the adaptive adjustment module.

3. The system according to claim 1, characterized in that The operating parameters include the pH value of the absorption tower and the concentration of the desulfurizer; the addition amount of the desulfurizer and the limestone slurry is dynamically adjusted according to the operating parameters by the adaptive adjustment module.

4. The system according to claim 3, characterized in that The dynamic adjustment method is: The adaptive adjustment module sets the target values ​​of sulfur oxide concentration in the tail gas and pH value of the absorption tower, constructs a PID controller according to the error between the real-time measured values ​​of the desulfurizer concentration and pH value of the absorption tower and the target values, converts the output signal of the PID controller into the valve opening of the desulfurizer addition pump and the limestone slurry addition pump, and monitors the changes of the desulfurizer concentration, sulfur oxide concentration in the tail gas and pH value of the absorption tower in real time, and feeds back the change information to the PID controller for continuous optimization; The PID parameters of the PID controller include a proportional coefficient, an integral coefficient, and a differential coefficient; the proportional coefficient is adjusted to determine the sensitivity of the proportional control to the error; the integral coefficient is adjusted to determine the sensitivity of the integral control to the error accumulation; the differential coefficient is adjusted to determine the sensitivity of the differential control to the error change rate, and the PID algorithm is implemented. The formula of the PID control algorithm is as follows: ； Among them, Control Signal is the control signal, K p , K i , K d are the proportional coefficient, integral coefficient, and differential coefficient respectively. e(t) is the error at time t. is the integral of the error, is the rate of change of error.

5. The system according to claim 1, characterized in that The catalytic reduction module converts SO2 in sulfur oxides into harmless SO3 through a catalyst at a preset system temperature, and reacts with ammonia to generate ammonium sulfate. The catalyst system of the catalytic reduction module includes a catalyst, a catalyst carrier, and a co-catalyst. The catalyst is vanadium pentoxide, the catalyst carrier is silicon dioxide, and the co-catalyst is potassium sulfate. The catalyst, catalyst carrier, and co-catalyst are introduced into the catalytic reduction module in solid form, and a catalytic oxidation reaction is carried out in the melt on the surface of the catalyst carrier.

6. The system according to claim 1, characterized in that The desulfurizing agent consists of seawater and sodium hydroxide solution.

7. The system according to claim 1, characterized in that The tail gas emission module uses an activated carbon adsorption tower to further remove sulfur oxides in the tail gas.

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