Long-path smoke exhaust system suitable for iCER-Diesel host

Abstract

A long-path smoke exhaust system suitable for an iCER-Diesel main machine is characterized in that an outlet of a waste gas economizer of the main machine is connected into a smoke exhaust header pipe through a pipeline, a plurality of smoke exhaust branch pipes extend out of the smoke exhaust header pipe, the smoke exhaust branch pipes at the two ends of the smoke exhaust header pipe are 90-degree arc-shaped bent pipes, and the smoke exhaust branch pipes are connected with a smoke exhaust and air return header pipe. The smoke exhaust and air return header pipe is connected with a main engine supercharger through a plurality of supercharging air inlet pipes, the depth of the end of each supercharging air inlet pipe inserted into the smoke exhaust and air return header pipe is 40 mm, an opening of each supercharging air inlet pipe is in a horn shape, the supercharging air inlet pipes are obliquely arranged upwards relative to the horizontal plane, insulating materials wrap the smoke exhaust and air return pipes, and the supercharging air inlet pipes are connected with a discharge cabinet through discharge pipes. According to the invention, the smoke exhaust back pressure entering the smoke exhaust header pipe is effectively reduced, the final smoke exhaust back pressure is less than 45mbar, and the water removal efficiency reaches 99.2%.

Description

Technical Field

[0001] The invention belongs to the technical field of unmanned ships, and in particular relates to a long-path smoke exhaust system suitable for an iCER-Diesel host machine. Background Art

[0002] WinGD iCER Diesel main engine is the latest product launched by WinGD. In order to adapt to the increasingly stringent environmental protection requirements of dual-fuel ship low-pressure gas system main engine, it is equipped with iCER Diesel system.

[0003] iCER stands for intelligent Control by Exhaust Recycling, which means intelligent exhaust gas circulation control in Chinese. The design concept of WinGD X92DF-iCER Diesel system is to wash and cool part of the exhaust gas from the main engine and then return it to the main engine supercharger, so that the carbon dioxide in the exhaust gas replaces part of the oxygen in the original scavenging air, lowers the intake temperature, and reduces the oxygen content concentration in the scavenging air, thereby achieving the purpose of reducing NOX emissions and meeting Tier III requirements.

[0004] iCER Diesel system has been promoted and applied in most shipyards. iCER Diesel generally includes two parts: water treatment system and smoke exhaust system. For the smoke exhaust system, it is divided into short path (such as Figure 1 ) and long paths (as shown in Figure 2 There are two design methods.

[0005] The short-path iCER exhaust system design causes a loss of flue gas volume because part of the flue gas has to return to the main engine turbocharger. For most ships currently, the main engine exhaust gas economizer is a common device. The loss of flue gas volume means that the evaporation capacity of the main engine exhaust gas economizer is insufficient, which has a certain impact on the economy of the ship. In addition, for ships with narrow engine rooms, the exhaust gas cooler cannot be arranged near the main engine, which also makes the short-path design impossible to achieve.

[0006] Long path iCER smoke exhaust system design, such as Figure 1 As shown in the figure, the exhaust gas from the main engine first passes through the main engine exhaust gas economizer, and then part of the exhaust gas enters the exhaust gas cooler. This design first ensures the evaporation capacity of the main engine exhaust gas economizer and improves the economy of the ship. At the same time, since the flue gas first passes through the main engine exhaust gas economizer, the temperature has been slightly reduced, so the cooling capacity of the exhaust gas cooler can also be appropriately reduced, saving the system design cost. In addition, for the narrow space of the engine room, the long-path iCER exhaust system design can arrange the exhaust gas cooler in the chimney area, which is more conducive to the layout of the engine room in a narrow space.

[0007] However, there are two problems with the design of the long-path iCER exhaust system. First, the long-path exhaust system means that the exhaust pipe is too long. In particular, the exhaust gas that passes through the exhaust gas cooler needs to flow from top to bottom in the exhaust pipe, which results in a very high exhaust back pressure. The increase in exhaust back pressure will lead to an increase in engine fuel consumption. According to WinGD's recommendation, the exhaust back pressure should be less than 45mbar. In addition, since the flue gas passes through the exhaust gas cooler, it will contain a certain amount of water, and the engine supercharger cannot withstand a large amount of water entering. Therefore, it is required that after the flue gas passes through the exhaust gas cooler and before entering the engine supercharger, the water in the flue gas needs to be separated by at least 90% to meet the requirements for entering the engine supercharger. Summary of the invention

[0008] In order to solve the above problems, the present invention provides a long-path smoke exhaust system suitable for the iCER-Diesel host, aiming to reduce the smoke exhaust back pressure and enhance the water removal efficiency. The technical solution adopted is:

[0009] A long-path exhaust system suitable for the iCER-Diesel main engine. The main engine exhaust economizer outlet is connected to the exhaust main pipe through a pipeline. Multiple exhaust branch pipes extend from the exhaust main pipe. The exhaust branch pipes at both ends of the exhaust main pipe are 90° arc-shaped elbows, and the exhaust branch pipes extending along the middle section of the exhaust main pipe are straight pipes. The exhaust branch pipes are connected to the exhaust return air main pipe.

[0010] The exhaust air return main pipe is connected to the main engine supercharger through multiple independent boost air intake pipes. A lower short pipe is added to the bottom of the exhaust air return main pipe and connected to the discharge pipe. Each boost air intake pipe is added to the bottom of the main engine supercharger inlet and connected to the discharge pipe. The boost air intake pipe is inserted into the main engine supercharger to a depth of 40mm, and the opening is trumpet-shaped. The boost air intake pipe is inclined upward relative to the horizontal plane. The exhaust air return pipeline is wrapped with insulating material, and each boost air intake pipe is connected to the discharge cabinet through a discharge pipe.

[0011] The above-mentioned long-path exhaust system is suitable for the iCER-Diesel host, and further, the supercharger has three exhaust outlets.

[0012] The above-mentioned long-path smoke exhaust system suitable for the iCER-Diesel host, further, the boost intake pipe is inclined upward by 5°-10° relative to the horizontal plane.

[0013] The above-mentioned long-path smoke exhaust system suitable for the iCER-Diesel main engine further has a back pressure regulating valve and an explosion-proof valve arranged in sequence on the main pipe entering the main engine exhaust economizer.

[0014] The above-mentioned long-path smoke exhaust system suitable for the iCER-Diesel main engine further has a pressurized air intake pipe fixed to the cabin wall panel through a smoke exhaust pipe bracket.

[0015] The above-mentioned long-path smoke exhaust system is suitable for the iCER-Diesel host. Furthermore, the main smoke exhaust pipe is 5800 mm long and 2520 mm in diameter.

[0016] The beneficial effects of the present invention are:

[0017] 1. The exhaust main pipe is optimized, which effectively reduces the exhaust back pressure entering the exhaust main pipe. The final exhaust back pressure is less than 45mbar, which reduces the size of the exhaust main pipe and is more conducive to the layout of the supercharger ventilation pipeline and the cabin layout in a small space.

[0018] 2. On long-path pipelines, all unnecessary elbow designs are eliminated, and large elbow designs with 3 times the pipe diameter are adopted for the necessary elbows, which effectively reduces the exhaust back pressure and reduces the space occupied by the chimney and the cabin.

[0019] 3. In the exhaust pipe returning to the supercharger, three small supercharged air intake pipes are designed to make the exhaust pipe layout more flexible and occupy less space, which is conducive to the layout of the cabin in a small space.

[0020] 4. After optimized exhaust pipe design, the water removal efficiency reaches 99.2%. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is the existing long path iCER smoke exhaust system design;

[0022] Figure 2 It is a schematic diagram of the structure of the smoke exhaust main pipe;

[0023] Figure 3 It is a schematic diagram of the structure in which a smoke exhaust return air main pipe is connected to multiple pressurized air intake pipes;

[0024] Among them, 1- exhaust main pipe, 2- exhaust return air main pipe, 3- exhaust branch pipe, 4- boost intake pipe, 5- lower short pipe. DETAILED DESCRIPTION

[0025] The present invention will be further described in conjunction with the accompanying drawings.

[0026] like Figure 1The figure shows a long-path exhaust system suitable for the iCER-Diesel main engine, and an exhaust pipe layout scheme in a large container ship project. The main engine exhaust economizer outlet is connected to the exhaust main pipe through a pipe, and multiple exhaust branch pipes extend from the exhaust main pipe. The exhaust branch pipes at both ends of the exhaust main pipe are 90° arc-shaped elbows, and the exhaust branch pipes extending along the middle section of the exhaust main pipe are straight pipes. The exhaust branch pipes are connected to the exhaust return air main pipe.

[0027] The 90° arc-shaped elbows at both ends of the smoke exhaust main pipe can effectively reduce the exhaust back pressure caused by the smoke exhaust pipe entering the smoke exhaust collecting pipe. At the same time, this design scheme also effectively reduces the size of the smoke exhaust main pipe. Taking a large container ship project as an example, the size of the smoke exhaust main pipe of the conventional design scheme is about 2520mm in diameter and 13400mm in length. The size of the smoke exhaust main pipe of the present invention is about 2520mm in diameter and 5800mm in length. The length of the smoke exhaust main pipe is shortened by 7600mm. Therefore, the design scheme of the smoke exhaust main pipe of the present invention is more conducive to compact cabin layout.

[0028] The smoke exhaust return air main pipe is connected to the main engine supercharger through multiple independent boost air intake pipes. The end of the boost air intake pipe is inserted into the smoke exhaust return air main pipe to a depth of 40 mm, and the opening is trumpet-shaped. The boost air intake pipe is inclined upward relative to the horizontal plane, and the smoke exhaust return air pipeline is wrapped with insulating material. A lower short pipe 5 is added to the bottom of the smoke exhaust return air main pipe and the bottom of each boost air intake pipe at the inlet, and is connected to the discharge pipe through the lower short pipe, and then connected to the discharge cabinet.

[0029] The main engine supercharger needs to be continuously supplied with air through the air duct. By reducing the size of the exhaust main pipe, it can be ensured that the ventilation duct has enough space to supply air to the supercharger. This design can also be extended to all ships where the exhaust main pipe hinders the layout of the ventilation duct.

[0030] The exhaust return air pipeline layout before entering the main engine supercharger adopts the form of 3 independent pressurized air intake pipes to enter the main engine supercharger. This design can effectively reduce the diameter of the exhaust pipe and has flexible layout.

[0031] The main purpose of wrapping the exhaust return air pipeline after the exhaust gas cooler with insulation is to prevent the moisture condensed on the exhaust pipe wall from volatilizing into water vapor and mixing into the flue gas due to the high temperature of the outer wall of the exhaust pipe. It ensures that after the moisture contacts the exhaust pipe wall, it will condense into water droplets and flow downward along the exhaust pipe wall, which can effectively separate the moisture in the flue gas.

[0032] On the return air and smoke exhaust pipeline, a short lower pipe is added to the smoke exhaust return main pipe and each boost intake pipe before entering the main engine supercharger and connected to the discharge pipe. This method can effectively collect the water droplets attached to the wall of the smoke exhaust pipe and discharge them into the discharge cabinet, which can effectively discharge the moisture in the smoke.

[0033] All boost intake pipes are designed with an upward inclination angle of 5-10°. This method ensures that the moisture attached to the exhaust pipe wall on the return air boost intake pipe can flow back to the main pipe or the boost intake pipe's discharge pipe through the inclination angle.

[0034] In addition, at the connection position where the boost intake pipe is inserted into the exhaust return air main pipe, the insertion depth is required to be increased to 40mm. This design method is to prevent the moisture condensed on the return air main pipe from flowing into the boost intake pipe. However, this design method will cause the exhaust back pressure to increase. Therefore, it is also necessary to make the insertion position into a bell-shaped mouth to reduce the exhaust back pressure.

[0035] This design scheme is needed for ships with small engine room space, which cannot be equipped with exhaust gas coolers, and whose exhaust pipes entering the main engine supercharger cannot be arranged under the main engine supercharger. At the same time, for some short-path exhaust designs, although the exhaust back pressure can meet the requirements, the present invention is also needed to improve the water removal efficiency.

Claims

1. A long-path smoke exhaust system suitable for iCER-Diesel host, characterized in that: A long-path exhaust system for an iCER-Diesel main engine, wherein the main engine exhaust economizer outlet is connected to an exhaust main pipe (1) through a pipeline, and a plurality of exhaust branch pipes (3) extend from the exhaust main pipe. The exhaust branch pipes at both ends of the exhaust main pipe are 90° curved pipes, and the exhaust branch pipes extending along the middle section of the exhaust main pipe are straight pipes. The exhaust branch pipes are connected to the exhaust return air main pipe (2); The exhaust air return main pipe is connected to the main engine supercharger through multiple independent boost air intake pipes. A lower short pipe is added to the bottom of the exhaust air return main pipe and connected to the discharge pipe. Each boost air intake pipe is added to the bottom of the main engine supercharger inlet and connected to the discharge pipe. The boost air intake pipe is inserted into the main engine supercharger to a depth of 40mm, and the opening is trumpet-shaped. The boost air intake pipe is inclined upward relative to the horizontal plane. The exhaust air return pipeline is wrapped with insulating material, and each boost air intake pipe is connected to the discharge cabinet through a discharge pipe.

2. A long-path smoke exhaust system suitable for an iCER-Diesel host according to claim 1, characterized in that: The supercharger has three exhaust outlets.

3. A long-path smoke exhaust system suitable for an iCER-Diesel host according to claim 1, characterized in that: The boost intake pipe is inclined upward by 5°-10° relative to the horizontal plane.

4. A long-path smoke exhaust system suitable for an iCER-Diesel host according to claim 1, characterized in that: The main pipe entering the main engine exhaust economizer is equipped with a back pressure regulating valve and an explosion-proof valve in sequence.

5. The long-path smoke exhaust system suitable for the iCER-Diesel host according to claim 1, characterized in that: The pressurized air intake pipeline is fixed to the cabin wall through the exhaust pipe bracket.

6. The long-path smoke exhaust system suitable for the iCER-Diesel host according to claim 1, characterized in that: The main exhaust pipe is 5800mm long and 2520mm in diameter.

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