Self-adaptive transportation ceramic membrane condensation ship desulfurization flue gas water heat recovery system

Abstract

The invention discloses a ship desulfurization flue gas water heat recovery device based on a transportation ceramic membrane condenser, which comprises a dust remover, an induced draft fan, a desulfurization tower, a ceramic membrane condenser, a chimney, a washing liquid tank and a mixing tank, and the output end of the dust remover is connected with the flue gas inlet of the desulfurization tower through a pipeline via the induced draft fan; a flue gas outlet of the desulfurization tower is connected with a chimney through a pipeline via a ceramic membrane condenser; a refrigerating medium end of the ceramic membrane condenser is connected with a seawater cooling system, and a condensate discharge end of the ceramic membrane condenser is connected with a washing liquid tank through a pipeline via a plate heat exchanger; a spray liquid reflux inlet of the desulfurization tower is connected with a washing liquid tank, an output port of the washing liquid tank is connected with a mixing tank, and the mixing tank is connected with a spray mechanism in the desulfurization tower through a spray pipe. The device is simple and compact in structure, water and waste heat in the desulfurized flue gas are efficiently recycled, and corrosion caused by directly supplementing and adding spraying liquid through seawater is avoided.

Description

Technical Field

[0001] The present invention specifically relates to an adaptive transport ceramic membrane condensation ship desulfurization flue gas hydrothermal recovery system. Background Technique

[0002] Marine transportation is highly favored in the field of cargo transportation due to its advantages such as low cost, large transportation volume, high safety, strong adaptability, and wide global coverage. Reducing the emission of acidic pollutants in ship exhaust gas and recycling the saturated wet flue gas of the desulfurization system are difficult problems that the industry urgently needs to solve. Further improving the ship desulfurization system has become an important topic for the green development of the shipping industry. In the traditional wet desulfurization system, the flue gas changes from unsaturated flue gas to saturated wet flue gas at 50 - 60 °C with a sensible heat of about 1.2 - 1.8 GJ / h after being washed by the desulfurization tower slurry. Direct emission results in low energy utilization efficiency. At the same time, the flue gas containing a small amount of desulfurization slurry and a large amount of water vapor escapes, causing white smoke to form a white plume, exacerbating marine haze and the pressure of ship fresh water replenishment. If the water vapor in the flue gas can be reasonably and effectively recycled, the water consumption of the desulfurization system will be greatly reduced. Currently, most domestic ships adopt the flue gas bypass technology to recover the flue gas waste heat, that is, bypass the high-temperature flue gas to the low-temperature section and directly mix and adjust the exhaust gas temperature, but it will form a dew point corrosion area and accelerate the damage of the flue duct structure. To recover the water in the saturated wet flue gas, the current common practice is to install a condensation heat exchanger, a water collector, etc. This practice usually has high requirements for the flue gas temperature and also requires installing devices such as a flue gas reheater, which increases the flue gas resistance, the complexity of the water extraction system, and cannot obtain high-purity fresh water resources. The components of the saturated wet flue gas after desulfurization and water extraction from the flue gas include water vapor, nitrogen, carbon dioxide, oxygen, soluble salts, a small amount of sulfur dioxide and acidic gases, and a small amount of nitrides. The present invention proposes a ship desulfurization flue gas hydrothermal recovery device based on a transport ceramic membrane condenser, aiming to efficiently recycle high-purity fresh water resources and low-grade flue gas waste heat.

[0003] Existing ship desulfurization flue gas hydrothermal utilization devices such as low-temperature / low-pressure economizers, organic Rankine cycles, flue gas bypass technologies, condensation heat exchangers and water collectors, and mechanical demisters have the following pain points: High risk of corrosion and working medium leakage: The low-temperature / low-pressure economizer treats the flue gas after wet desulfurization containing acidic liquids, which is prone to cause low-temperature corrosion of the heat exchange tubes. The flue gas bypass technology is prone to form a dew point corrosion area and accelerate the damage of the flue duct structure. Under the conditions of ship vibration and inclination, the probability of seal failure of the organic Rankine cycle increases, and the leakage of fluorinated working media is harmful to human health.

[0004] Large space occupation and weak low-temperature adaptability: Large shell-and-tube condensers and flue gas reheaters occupy a large deck area. The Kalina cycle requires multi-stage fractionating towers and rectifying devices, and the equipment volume is 50% larger than that of the ORC, making it difficult to fit into the compact layout of ships. The low-temperature / low-pressure economizer requires the flue gas temperature to be greater than 120°C, while the flue gas from ship desulfurization often drops to 50 - 70°C and cannot be directly applied. When the heat source temperature of the absorption heat pump is <70°C, the heating performance drops below 0.8, resulting in poor economy.

[0005] High system complexity and poor shock load resistance: The ORC cycle and Kalina cycle have relatively high utilization rates of low-grade waste heat, but the equipment has a complex structure, a large volume, and high maintenance costs, and is not suitable for ship desulfurization flue gas treatment. The load fluctuation of the ship's main engine causes the COP of the absorption heat pump to fluctuate by more than 20%, with poor shock load resistance and insufficient system stability. The mechanical demister can only recover liquid water droplets and cannot handle gaseous water vapor. Summary of the Invention

[0006] The purpose of the present invention is to provide a ship desulfurization flue gas hydrothermal recovery device based on a transport ceramic membrane condenser, which has a simple and compact structure, can efficiently recover the moisture and waste heat in the desulfurization flue gas, uses seawater as the cooling water of the ceramic membrane condenser, and then supplements and adds the condensate of the ceramic membrane condenser to the circulating spray liquid of the desulfurization tower, and can adjust its concentration to avoid the corrosion caused by directly adding seawater.

[0007] The technical solution adopted by the present invention is as follows: A ship desulfurization flue gas hydrothermal recovery device based on a transport ceramic membrane condenser, comprising a dust collector, an induced draft fan, a desulfurization tower, a ceramic membrane condenser, a chimney, a washing liquid tank, and a mixing tank. The output end of the dust collector is connected to the flue gas inlet of the desulfurization tower through a pipeline via the induced draft fan, and the flue gas outlet of the desulfurization tower is connected to the chimney through a pipeline via the ceramic membrane condenser; The refrigerant medium end of the ceramic membrane condenser is connected to a seawater cooling system, using seawater as the refrigerant medium of the ceramic membrane condenser. The condensate discharge end of the ceramic membrane condenser is connected to the washing liquid tank through a pipeline via a plate heat exchanger; A spray mechanism is provided in the desulfurization tower. The spray liquid return port at the lower part of the desulfurization tower is connected to the washing liquid tank. The output port of the washing liquid tank is connected to the mixing tank, and the mixing tank is connected to the spray mechanism in the desulfurization tower through a spray pipe.

[0008] Preferably, the spray mechanism includes multiple spray layers. Some of the spray layers are spray layers that spray downward, and some of the spray layers are spray layers that spray upward; the spray layers that spray downward are arranged above the spray layers that spray upward.

[0009] The flue gas inlet of the desulfurization tower is arranged below the spray mechanism.

[0010] Preferably, a pump and an electromagnetic valve are provided on the connecting pipe between the spraying mechanism and the mixing tank.

[0011] Preferably, a flow monitor and an intelligent water valve are provided on the connecting pipe between the refrigerant medium end of the ceramic membrane condenser and the seawater cooling system. Preferably, a circulating water pump is provided on the connecting pipe between the condensate discharge end of the ceramic membrane condenser and the plate heat exchanger.

[0012] Preferably, the mixing tank is connected to a NaOH tank.

[0013] Preferably, the plate heat exchanger is connected to an auxiliary boiler.

[0014] Preferably, the ceramic membrane condenser includes a box body and a plurality of ceramic membrane tubes arranged side by side in the box body.

[0015] Preferably, the ceramic membrane tube includes a support layer, an intermediate layer, and a selective layer arranged in sequence from outside to inside, with a staggered arrangement, a pore diameter of 10 nm, a porosity of 42.5%, and a total of 45 ceramic membrane tubes with a length of 0.8 m are placed.

[0016] Preferably, 2 temperature sensors are provided in the ceramic membrane tube; A flow monitor and an intelligent water valve are provided on the connecting pipe between the refrigerant medium end of the ceramic membrane condenser and the seawater cooling system; the intelligent water valve is connected to the temperature sensor and the flow monitor; When the temperature reaches the highest threshold detected by the temperature sensor, the opening of the intelligent water valve increases, so that the flow rate supplied by the seawater cooling system increases; when the cooling water flow rate increases detected by the flow monitor and the temperature reaches the lowest threshold detected by the temperature sensor, the opening of the intelligent water valve decreases, so that the flow rate supplied by the seawater cooling system decreases, reducing the heat transfer temperature difference on both sides of the membrane.

[0017] The beneficial effects of the present invention are: The structure of the present invention is simple and compact. After the ceramic membrane condenser is connected to the flue gas discharged from the desulfurization tower, the capillary condensation and film condensation mechanisms are applied to the treatment of saturated wet flue gas after ship desulfurization, realizing efficient recovery of moisture and waste heat in the desulfurized flue gas, using seawater as the cooling water of the ceramic membrane condenser, and then supplementing and adding the condensate of the ceramic membrane condenser to the circulating spray liquid of the desulfurization tower, and its concentration can be adjusted, avoiding the corrosion caused by directly supplementing and adding seawater. Description of the Drawings

[0018] Figure 1 It is a schematic diagram of the principle of the self-adaptive transport ceramic membrane condensation ship desulfurization flue gas water and heat recovery system in the embodiment of the present invention.

[0019] Figure 2 It is the front view of the transport ceramic membrane condenser assembly in the embodiment of the present invention.

[0020] Figure 3 It is a perspective view of the transport ceramic membrane condenser assembly in the embodiment of the present invention.

[0021] Figure 4 It is Figure 2 a sectional view taken along line A-A of

[0022] Figure 5 It is a schematic structural view of a single-tube ceramic membrane tube in the embodiment of the present invention.

[0023] Figure 6 It is a schematic structural view of the temperature measuring sensor in the embodiment of the present invention.

[0024] Figure 7 It is a schematic diagram of the control principle of the intelligent water valve in the embodiment of the present invention.

[0025] In the figure: 1 - dust collector; 2 - induced draft fan; 3 - desulfurization tower; 4 - spray layer; 5 - ceramic membrane condenser; 6 - NaOH tank; 7 - washing liquid tank; 8 - mixing tank; 9 - intelligent water valve; 10 - flow monitor; 11 - circulation water pump; 12 - plate heat exchanger; 13 - auxiliary boiler; 14 - seawater cooling system; 15 - chimney; 16 - temperature measuring sensor. Detailed implementation manners

[0026] In order to make the objectives, technical solutions and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0027] In the description of the present invention, it should be understood that if there are terms involved such as "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of the described features. In the description of the present invention, "a plurality" means two or more, unless otherwise specifically and clearly defined.

[0028] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection. It can be a mechanical connection or an electrical connection. It can be a direct connection or an indirect connection through an intermediate medium, and it can be the communication inside two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] Embodiment 1 A ship desulfurization flue gas hydrothermal recovery device based on a transport ceramic membrane condenser, as Figures 1 - 6 shown, includes a dust collector 1, an induced draft fan 2, a desulfurization tower 3, a ceramic membrane condenser 5, a chimney 15, a washing liquid tank 7, and a mixing tank 8. The output end of the dust collector 1 is connected to the flue gas inlet of the desulfurization tower 3 through a pipeline via the induced draft fan 2. The flue gas outlet of the desulfurization tower 3 is connected to the chimney 15 through a pipeline via the ceramic membrane condenser 5; The refrigerant end of the ceramic membrane condenser 5 is connected to a seawater cooling system 14, using seawater as the refrigerant of the ceramic membrane condenser 5. The condensate discharge end of the ceramic membrane condenser 5 is connected to the washing liquid tank 7 through a pipeline via a plate heat exchanger 12; A spraying mechanism is provided inside the desulfurization tower 3. The spraying liquid return port at the lower part of the desulfurization tower 3 is connected to the washing liquid tank 7. The output port of the washing liquid tank 7 is connected to the mixing tank 8. The mixing tank 8 is connected to the spraying mechanism inside the desulfurization tower 3 through a spraying pipe.

[0030] Further, the spraying mechanism includes a plurality of spraying layers 4. A part of the spraying layers are spraying layers that spray downward, and another part of the spraying layers are spraying layers that spray upward; the spraying layers that spray downward are arranged above the spraying layers that spray upward.

[0031] Further, the flue gas inlet of the desulfurization tower 3 is arranged below the spraying mechanism.

[0032] Further, a pump and an electromagnetic valve are provided on the connecting pipeline between the spraying mechanism and the mixing tank 8.

[0033] Further, a flow monitor 10 and an intelligent water valve 9 are provided on the connecting pipeline between the refrigerant end of the ceramic membrane condenser 5 and the seawater cooling system 14. Further, a circulating water pump 11 is provided on the connecting pipeline between the condensate discharge end of the ceramic membrane condenser 5 and the plate heat exchanger 12.

[0034] Further, the mixing tank 8 is connected to a NaOH tank 6.

[0035] Further, the plate heat exchanger 12 is connected to an auxiliary boiler 13.

[0036] Example 2 As Figures 2 - 5 shown, on the basis of Example 1, the ceramic membrane condenser is further defined, and the performance of Example 2 after definition is better.

[0037] The ceramic membrane condenser includes a plurality of ceramic membrane tubes arranged side by side; the plurality of ceramic membrane tubes are divided into multiple groups, each group constitutes a ceramic membrane module, and when the multiple ceramic membrane modules are spliced, the ceramic membrane tubes in each ceramic membrane module are arranged in a staggered manner.

[0038] Furthermore, the ceramic membrane tube includes a support layer, an intermediate layer and a selective layer arranged in sequence from outside to inside, which are arranged in a staggered manner, with a pore size of 10 nm and a porosity of 42.5%. A total of 45 ceramic membrane tubes with a length of 0.8 m are placed.

[0039] Furthermore, there are 2 temperature sensors in the ceramic membrane tube; On the connecting pipe between the refrigerant end of the ceramic membrane condenser 5 and the seawater cooling system 14, there are a flow monitor 10 and an intelligent water valve 9; the intelligent water valve is connected to the temperature sensor and the flow monitor; When the temperature reaches the highest threshold detected by the temperature sensor, the opening of the intelligent water valve increases, so that the flow supplied by the seawater cooling system 14 increases; when the cooling water flow increases detected by the flow monitor 10 and the temperature reaches the lowest threshold detected by the temperature sensor, the opening of the intelligent water valve decreases, so that the flow supplied by the seawater cooling system 14 decreases, reducing the heat transfer temperature difference on both sides of the membrane.

[0040] As Figure 7 shown, the intelligent water valve is connected to the terminal main system in the engine room and / or the Iot Internet of Things platform, the terminal main system in the engine room is connected to the Iot Internet of Things platform, and the temperature sensor and the flow monitor are connected to the Iot Internet of Things platform or the terminal main system in the engine room.

[0041] A flow monitor and an intelligent water valve device are arranged in the cooling water transportation pipeline, which can adapt to the temperature rise of the cooling water and adjust the opening of the water valve to reduce the water flow to improve the mass transfer efficiency of the membrane tube. Determine the basic operating parameters of the system according to the application scenario, comprehensively consider the feasibility and stability of the device, explore the water heat recovery efficiency of TMC membranes with different pore sizes for desulfurized flue gas, then select the membrane module material and pore size used in the device, and establish the models of each basic component and the overall model of the membrane module.

[0042] The working principle of the present invention: The present invention designs an adaptive transport ceramic membrane condensation ship desulfurization flue gas hydrothermal recovery device, which applies the capillary condensation and film condensation mechanisms to the treatment of saturated wet flue gas after ship wet desulfurization through the ceramic membrane condenser 5 to achieve efficient recovery of moisture and waste heat in the desulfurization flue gas. The ceramic membrane condenser in this device belongs to the TMC (Transport Membrane Condenser) transport membrane condenser. The principle of this device is mainly that the two mechanisms of capillary condensation and film condensation cause water vapor to condense, that is, the continuously flowing cooling water inside the membrane tubes of the ceramic membrane module exchanges heat with the flue gas flowing outside the membrane tubes to reduce the temperature of the flue gas, and the water vapor in the flue gas condenses. Under the action of the Knudsen diffusion effect, capillary pressure, and the pressure difference between the water vapor partial pressure outside the membrane and the cooling water pressure inside the membrane, the condensed water penetrates into the membrane tubes. The cooling water temperature rises due to absorbing the sensible heat released by the flue gas cooling and the latent heat of vaporization released by the water vapor condensation, thereby realizing the recovery of flue gas moisture and heat and effectively reducing the white plume pollution. The ceramic membrane is composed of a support layer, an intermediate layer, and a selective layer, arranged in a staggered pattern, with a pore size of 10 nm and a porosity of 42.5%. A total of 45 membrane tubes with a length of 0.8 m are placed, and the main parameters are shown in Table 1.

[0043]

[0044] Table 1 Parameters of the ceramic membrane module One ceramic membrane condenser 5 can include 4 - 5 groups of ceramic membrane modules. Each ceramic module can hold 45 ceramic membrane tubes. In the water vapor transport mechanism on the nanoscale ceramic membrane surface of the ceramic membrane tubes, the water vapor molecules in capillary condensation condense due to the surface tension effect in the pores of the membrane, forming a pseudo - liquid, which promotes the water vapor to cross the membrane pores with higher efficiency. Capillary condensation can promote water vapor condensation by reducing the pore temperature and increasing the heat transfer temperature difference. The smaller the pore size and the higher the flue gas temperature, the greater the temperature difference between them. The project team members successively carried out hydrothermal recovery comparative tests on ceramic membrane materials with pore sizes of 10 μm, 100 μm, 10 nm, and 20 nm. Under the conditions of keeping the flue gas temperature, relative humidity, and water vapor partial pressure constant, the nanoscale pore size has a higher mass transfer efficiency than the microscale. Therefore, the ceramic membrane with a pore size of 10 nm used in this device can exhibit more excellent condensation mass transfer performance.

[0045] Condensation plays a crucial role in the flue gas moisture recovery technology. Its core lies in efficiently separating water vapor from the flue gas while intercepting other gas components such as acidic gas-liquid mixtures on the flue gas side. The condensation mechanism can generally be divided into two modes: one is filmwise condensation, that is, the cooling effect caused by the temperature difference at the phase change interface, and water vapor directly condenses on the film surface; the other is capillary condensation, that is, the orifice plate effect caused by the pressure change in small-scale pores. When the condensable gas contacts the microporous surface, the van der Waals force between molecules promotes the formation of an adsorption film of condensable gas molecules on the pore surface. Subsequently, due to the capillary pressure difference generated by the small pore diameter, it promotes the migration of condensable water vapor on the pore wall into the pores and condenses into a liquid here. However, due to the action of gravity, some condensed water cannot be captured by the ceramic membrane in time, and a condensate water tank needs to be installed at the bottom of the membrane module box. To improve the heat transfer efficiency of filmwise condensation, starting from the perspective of reducing the thickness of the condensate liquid film, the present invention uses a hybrid hydrophilic / hydrophobic heat transfer surface instead of an ordinary heat transfer surface, and the heat transfer coefficient is increased by nearly 2 times.

[0046] This system consists of a nano-ceramic membrane condenser 5, a plate heat exchanger 12, a dust collector 1, an induced draft fan 2, a desulfurization tower 3, a circulating water pump 11, a seawater cooling system 14, a washing liquid tank 7, a temperature measuring sensor 16, a flow monitor 10 and an intelligent water valve 9. There are a total of 45 ceramic membrane tubes, which are horizontally installed in a box wrapped by a stainless steel shell. The pore diameter is 10 nanometers. They are arranged in the horizontal tail flue behind the ship's desulfurization tower and before the smoke exhaust passage. The box shell, cooling water pipes and exhaust pipes are all insulated with high-temperature resistant materials to prevent heat dissipation. The total membrane area is about 3 square meters. The waste smoke discharged from the ship's engine first reacts with SCR for denitrification in the desulfurization system, and then enters the desulfurization tower after dust removal and reacts with the slurry under the action of the induced draft fan. After desulfurization, the waste gas turns into saturated wet flue gas, in which the volume fraction of water vapor is about 12% - 16%. When the wet flue gas flows vertically upward and scours the nano-ceramic membrane module, the cooling water in the membrane tube flows horizontally under the siphon effect generated by the circulating water pump and the seawater cooling system. Its pressure is slightly lower than the flue gas pressure. The cooling water comes from the seawater cooling system. A condensate discharge pipe is provided at the bottom of the membrane module box to collect the uncaught condensate formed by the condensation of the wet flue gas. As the cooling water flow rate increases, the shear stress inside the membrane tube increases, which will significantly weaken the temperature boundary layer and reduce the mass transfer efficiency between the ceramic membrane and the wet flue gas. To maintain the heat and mass transfer efficiency of the membrane tube at a high level, the ceramic membrane tube is divided into 6 sections, and 2 temperature measuring sensors are evenly arranged along the membrane wall for monitoring. When the cooling water flow rate increases and the average temperature rise is lower and reaches the lowest threshold of the temperature measuring sensor, at this time, based on the communication module of the Iot Internet of Things cloud platform, the opening of the intelligent water valve in the pipeline of the cooling system to the membrane module is automatically reduced to lower its flow rate, reduce the heat transfer temperature difference on both sides of the membrane, and improve the heat and mass transfer efficiency. Conversely, the opening is increased to increase the water flow rate. After obtaining the multi-sensor data, it is uploaded to the terminal device in the engine room. Through the authorized user logging in to the cloud platform storing the data information of the desulfurization system, the duty engineer can view the cooling water temperature and flow rate status inside the membrane tube in real time, and remotely open, close, increase or decrease the opening of the water valve according to the actual situation. At the same time, the upper and lower thresholds of the temperature measuring sensor can be adjusted to ensure the mass transfer efficiency of the ceramic membrane. The communication module is connected for two-way data transmission with the terminal main system based on the zigbee wireless communication network. The Zigbee protocol is designed specifically for low power consumption, suitable for the long-term operation of the ship's intelligent water valve. Moreover, it supports the Mesh network topology, and the nodes automatically relay communication. A single-point failure does not affect the global communication. Under the complex cabin structure of the ship, the signal coverage can still reach 99% communication success rate through multi-hop routing. The terminal main system connected by the marine wifi router is connected with the GPRS wireless mobile communication device, and remote automatic control can be realized after accessing the Internet of Things.The temperature sensor is used to measure the temperature of the cooling water in the membrane tube and upload the data to the terminal cloud platform in the engine room. The flow monitor is used to measure the water flow rate in the cooling water transport pipeline and upload the data to the cloud platform. The intelligent water valve is located at the outlet of the cooling system and receives signals to control the opening degree of the water valve.

[0047] Under the adaptive cooling water temperature and flow control system, high-temperature flue gas and low-temperature cooling water flow in opposite directions on both sides of the membrane tube to achieve heat exchange. The water vapor in the flue gas is transported synergistically to the cooling water in the hydrophilic membrane tube under multiple transport modes such as the Knudsen diffusion effect, Poiseuille flow, and double condensation mechanism. At the same time, the temperature of the flue gas decreases, and sensible heat is released through the heat convection mechanism. Moreover, the water vapor in the flue gas diffuses and condenses on the inner surface of the membrane tube, generating a large amount of latent heat, which increases the temperature and flow rate of the cooling water in the membrane tube. The acidic substances in the wet flue gas are blocked on the flue gas side by the hybrid hydrophilic / hydrophobic membrane, improving the purity of the recycled water resources. The condensed water flows out of the membrane tube outlet and is partly incorporated into the seawater cooling system for makeup water by the circulating water pump, and the other part is incorporated into the washing tank in the fresh water circulation system, reducing the water loss in the closed desulfurization system and achieving internal water circulation in the desulfurization system. When the flue gas flowing out of the ceramic membrane module has a reduced temperature and moisture content and is discharged through the chimney, the white plume can be basically eliminated, which is beneficial to reducing the frequent occurrence of the marine haze environment. To utilize the heat recovered from the condensed water, a plate heat exchanger is installed to transfer the heat in the heated condensed water to preheat the feed water of the auxiliary boiler or to be used as domestic hot water to meet the bathing needs of the crew, reducing fuel and energy consumption and achieving high-efficiency energy conservation. The temperature of the condensed water passing through the heat exchanger is reduced to the initial water temperature and returns to the washing tank to dilute the continuously increasing NaOH concentration in the washing liquid, extending the treatment cycle of the wastewater in the closed desulfurization system and significantly reducing the cost of the wastewater treatment unit.

[0048] In summary, the present invention proposes a ship desulfurization flue gas water heat recovery device based on a transport membrane condenser. The transport membrane condenser technology has the advantages of 1. large gas-liquid contact area, small equipment size, simple process flow and low environmental pollution, and has great potential in recovering moisture and waste heat in saturated wet flue gas from ship desulfurization. 2. Compared with the above-mentioned traditional flue gas waste heat recovery technology, it has higher heat transfer efficiency and can also solve problems such as corrosion and high energy consumption. 3. Due to the selective permeability of the hydrophilic / hydrophobic membrane, the acidic gas-liquid mixture and particulate matter in the saturated wet flue gas are intercepted on the flue gas side, thereby improving the purity of the water intake and efficiently eliminating white plumes. 4. Two temperature sensors are arranged in the ceramic membrane tube, a flow monitor is arranged in the cooling water transport pipeline, and an intelligent water valve device can adapt to the cooling water temperature rise and adjust the water valve opening to reduce the water flow to improve the mass transfer efficiency of the membrane tube. After investigating the application status of ship desulfurization towers on the spot and consulting relevant literature, the basic operating parameters of the system were determined according to the application scenario, the feasibility and stability of the device were comprehensively considered, and the water heat recovery efficiency of TMC membranes with different pore sizes for desulfurized flue gas was explored. Then, the membrane component materials and pore sizes used in the device were selected, and the basic component models and overall models of the membrane components were established. (1): Transport ceramic membrane condenser flue gas water heat recovery system at 10nm pore size 1 m 2 The maximum water recovery is 6.7kg / (m 2 ·h), the maximum heat recovery is 21.27MJ / (m 2 ·h). Due to the selective permeability of the mixed hydrophilic / hydrophobic membrane, the acidic gas-liquid mixture in the flue gas after desulfurization is synergistically removed to ensure the purity of the condensate. Clean water resources can be used to supplement the desulfurization washing liquid and seawater cooling system, alleviate the corrosion risk caused by large amounts of seawater cooling, and dilute the increasing NaOH solution in the washing tank, extend the working cycle of the wastewater treatment unit in the closed desulfurization tower system, and significantly reduce its wastewater treatment cost. (2): The transportation ceramic membrane condenser has a more compact footprint than other flue gas water heat recovery devices and is more suitable for ship space allocation. It can efficiently recover low-grade desulfurized wet flue gas water heat, reduce the temperature of saturated wet flue gas, reduce water mist and eliminate white smoke plumes, reduce marine haze, and have low process complexity and simple operation. (3): The heat recovered by the transportation ceramic membrane condenser can heat the cooling water in the membrane tube. After passing through the plate heat exchanger, it can be used to preheat the feed water for the ship's auxiliary boiler or supply the main engine warm cylinder to improve combustion efficiency and drive the ORC system to generate electricity, supplementing the power demand of the equipment. The energy-saving and emission reduction effects are obvious. (4): The adaptive intelligent water valve control system can automatically adjust the cooling water flow rate to maintain the cooling water temperature rise, improve the mass transfer efficiency between the ceramic membrane and the saturated wet flue gas, and increase its water recovery volume and recovery heat flux.

[0049] It should be noted that in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements not only includes those elements but also includes other elements not expressly listed, or further includes elements inherent to such process, method, article or device.

[0050] It should be understood that those of ordinary skill in the art can make improvements or modifications based on the above description, and all such improvements and modifications shall fall within the protection scope of the appended claims of the present invention.

Claims

1. A ship desulfurization flue gas hydrothermal recovery device based on a transport ceramic membrane condenser, characterized in that: It includes a dust collector (1), an induced draft fan (2), a desulfurization tower (3), a ceramic membrane condenser (5), a chimney (15), a washing liquid tank (7) and a mixing tank (8). The output end of the dust collector (1) is connected to the flue gas inlet of the desulfurization tower (3) via a pipeline through the induced draft fan (2), and the flue gas outlet of the desulfurization tower (3) is connected to the chimney (15) via a pipeline through the ceramic membrane condenser (5). The refrigerant medium end of the ceramic membrane condenser (5) is connected to a seawater cooling system (14), and the condensate discharge end of the ceramic membrane condenser (5) is connected to the washing liquid tank (7) via a pipeline through a plate heat exchanger (12). The spray liquid return port of the desulfurization tower (3) is connected to the washing liquid tank (7), the output port of the washing liquid tank (7) is connected to the mixing tank (8), and the mixing tank (8) is connected to the spray mechanism in the desulfurization tower (3) via a spray pipe.

2. The ship desulfurization flue gas hydrothermal recovery device based on a transport ceramic membrane condenser according to claim 1, characterized in that: The spray mechanism includes a plurality of spray layers (4). Some of the spray layers are spray layers that spray downward, and some of the spray layers are spray layers that spray upward; the spray layers that spray downward are arranged above the spray layers that spray upward.

3. The ship desulfurization flue gas hydrothermal recovery device based on a transport ceramic membrane condenser according to claim 2, wherein: Pumps and electromagnetic valves are provided on the connecting pipeline between the spray mechanism and the mixing tank (8).

4. The ship desulfurization flue gas hydrothermal recovery device based on a transport ceramic membrane condenser according to claim 1, characterized in that: A flow monitor (10) and an intelligent water valve (9) are provided on the connecting pipeline between the refrigerant medium end of the ceramic membrane condenser (5) and the seawater cooling system (14).

5. The ship desulfurization flue gas hydrothermal recovery device based on a transport ceramic membrane condenser according to claim 1, characterized in that: A circulating water pump (11) is provided on the connecting pipeline between the condensate discharge end of the ceramic membrane condenser (5) and the plate heat exchanger (12).

6. The ship desulfurization flue gas hydrothermal recovery device based on a transport ceramic membrane condenser according to claim 1, characterized in that: The mixing tank (8) is connected to a NaOH tank (6).

7. The ship desulfurization flue gas hydrothermal recovery device based on a transport ceramic membrane condenser according to claim 1, characterized in that: The plate heat exchanger (12) is connected to an auxiliary boiler (13).

8. The ship desulfurization flue gas hydrothermal recovery device based on a transport ceramic membrane condenser according to claim 1, characterized in that: The ceramic membrane condenser includes a box body and a plurality of ceramic membrane tubes arranged side by side in the box body.

9. The ship desulfurization flue gas hydrothermal recovery device based on a transport ceramic membrane condenser according to claim 8, characterized in that: The ceramic membrane tube includes a support layer, an intermediate layer and a selective layer arranged in sequence from the outside to the inside. The pore size of the selective layer is 10 nm, and the porosity is 42.5%.

10. The ship desulfurization flue gas hydrothermal recovery device based on a transport ceramic membrane condenser as claimed in claim 8, characterized in that: A temperature measuring sensor is provided in the ceramic membrane tube. A flow monitor (10) and an intelligent water valve (9) are provided on the connecting pipeline between the refrigerant medium end of the ceramic membrane condenser (5) and the seawater cooling system (14); the intelligent water valve is connected to the temperature measuring sensor and the flow monitor. When the temperature reaches the highest threshold detected by the temperature measuring sensor, the opening of the intelligent water valve increases, so that the flow supplied by the seawater cooling system (14) increases; when the cooling water flow increases detected by the flow monitor (10) and the temperature reaches the lowest threshold detected by the temperature measuring sensor, the opening of the intelligent water valve decreases, so that the flow supplied by the seawater cooling system (14) decreases, reducing the heat transfer temperature difference across the membrane.

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