Low-pressure double-wall pipe fresh water purge system for large container ships

Abstract

The invention discloses a low-pressure double-walled pipe fresh water purge system for a large container ship, wherein the outlet of a methanol daily tank is connected to the inlet of a methanol supply pump, the outlet of the methanol supply pump is connected to the inlet of a heat exchanger, the outlet of the heat exchanger is connected to the inlet of a main engine methanol liquid supply double-walled pipe, the pipeline between the outlet of the heat exchanger and the inlet of the main engine methanol liquid supply double-walled pipe is sequentially connected with a first liquid return pipe and a first fresh water purge pipe, the outlet of the first liquid return pipe is connected to the inlet of a purge and discharge cabinet, a liquid return valve is provided on the first liquid return pipe, the first liquid return pipe between the liquid return valve and the purge and discharge cabinet is connected to a second fresh water purge pipe, the outlet of the main engine methanol liquid supply double-walled pipe is connected to the inlet of the purge and discharge cabinet, the pipeline between the methanol supply pump and the heat exchanger is connected to a second liquid return pipe, the pipeline between the methanol supply pump and the methanol daily tank is provided with a second conversion valve, and the outlet of the purge and discharge cabinet is connected to the second conversion valve. The use of the system improves the purge efficiency of the methanol liquid supply system.

Description

Technical Field

[0001] The invention relates to the technical field of shipbuilding, and in particular to a low-pressure double-walled pipe fresh water purge system for a large container ship. Background Art

[0002] As emission requirements become increasingly stringent, dual-fuel diesel engines are gradually being promoted in the marine industry as a clean emission solution. Methanol, as a low-flashpoint fuel that is liquid at room temperature and pressure, is gaining more and more attention from shipowners. At present, nitrogen is usually used for purging of ship methanol supply systems, but nitrogen purging has problems such as low purging efficiency and high gas consumption.

[0003] Therefore, it is necessary to provide a low-pressure double-walled pipe fresh water purge system for large container ships to solve the above technical problems. Summary of the invention

[0004] The purpose of the present invention is to provide a low-pressure double-walled pipe fresh water purge system for a large container ship in view of the deficiencies in the prior art, so as to improve the purge efficiency of a methanol liquid supply system.

[0005] To achieve the above object, the technical solution adopted by the present invention is:

[0006] A low-pressure double-walled pipe fresh water purge system for a large container ship includes a methanol liquid supply system, wherein the methanol liquid supply system includes a methanol daily tank, wherein the outlet of the methanol daily tank is connected to the inlet of a methanol supply pump, wherein the outlet of the methanol supply pump is connected to the inlet of a heat exchanger, wherein the outlet of the heat exchanger is connected to the inlet of a main engine methanol liquid supply double-walled pipe, wherein a first liquid return pipe and a first fresh water purge pipe are sequentially connected on a pipeline between the outlet of the heat exchanger and the inlet of the main engine methanol liquid supply double-walled pipe, wherein a first double-blocking valve is arranged between the first liquid return pipe and the heat exchanger, wherein a second double-blocking valve is arranged between the first liquid return pipe and the first fresh water purge pipe, and wherein the first liquid return pipe is connected to the first fresh water purge pipe. The pipe outlet is connected to the inlet of the purge and discharge tank, a liquid return valve is provided on the first liquid return pipe, the first liquid return pipe between the liquid return valve and the purge and discharge tank is connected to the second fresh water purge pipe, the main engine methanol liquid supply double-wall pipe outlet is connected to the purge and discharge tank inlet, the pipeline between the methanol supply pump and the heat exchanger is connected to the second liquid return pipe, a first conversion valve is provided on the second liquid return pipe, one outlet of the first conversion valve is connected to the inlet of the purge and discharge tank, and the other outlet is connected to the inlet of the methanol daily tank, a second conversion valve is provided on the pipeline between the methanol supply pump and the methanol daily tank, and the outlet of the purge and discharge tank is connected to the second conversion valve.

[0007] Preferably, a double filter is provided between the heat exchanger and the first double isolation valve.

[0008] Preferably, both the first fresh water purge pipe and the second fresh water purge pipe are provided with a purge inlet valve.

[0009] Preferably, the outlet of the double-walled pipe for methanol liquid supply of the main engine is provided with a purge valve and a safety valve.

[0010] Preferably, the outer tube of the main engine methanol liquid supply double-wall tube is connected to a ventilation pipeline, an adjustable flow orifice plate is provided at the inlet of the ventilation pipeline, and a gas detector is provided at the outlet of the ventilation pipeline.

[0011] Preferably, a flow regulating valve is provided on the second liquid return pipe at the front end of the inlet of the first conversion valve.

[0012] Preferably, the tops of the methanol daily tank and the purge and discharge cabinet are both provided with a vent pipe and an inerting pipe.

[0013] Compared with the prior art, the present invention has the following advantages:

[0014] 1. The present invention adopts marine pressure fresh water to purge the methanol remaining in the methanol supply pipeline, replacing the nitrogen purge used in existing ships. The purge effect and energy efficiency are significantly improved, the energy consumption of nitrogen production and pressurization is effectively reduced, and the configuration and layout of related nitrogen production equipment and pressurization and storage equipment are omitted.

[0015] 2. The present invention designs a purge and discharge cabinet, and connects the purge and discharge cabinet with the methanol supply system, and transports the mixture of methanol and fresh water to the main engine methanol nozzle through the methanol supply system. The mixture can be sprayed into the cylinder for mixed combustion in the fuel mode, reducing waste liquid treatment and subsequent pollution.

[0016] 3. The scheme of the present invention has a simple and safe system design, convenient operation and maintenance, and flexible use, and is suitable for application and promotion in various types of methanol dual-fuel ships. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural diagram of the low-pressure double-walled pipe fresh water purge system of a large container ship;

[0018] Among them, 1-methanol daily tank, 2-methanol supply pump, 3-heat exchanger, 4-methanol liquid supply double-wall pipe, 5-first return liquid pipe, 6-first fresh water purge pipe, 7-first double isolation valve, 8-second double isolation valve, 9-return liquid valve, 10-second fresh water purge pipe, 11-purge inlet valve, 12-purge valve, 13-safety valve, 14-adjustable flow orifice plate, 15-gas detector, 16-second return liquid pipe, 17-first conversion valve, 18-flow regulating valve, 19-second conversion valve, 20-purge discharge cabinet DETAILED DESCRIPTION

[0019] The present invention is further explained below in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. After reading the present invention, various equivalent forms of modifications to the present invention by those skilled in the art all fall within the scope defined by the claims attached to this application.

[0020] In the present invention, unless otherwise clearly stipulated and limited, the terms such as "installation", "setting", "connection", "fixed connection" and the like 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; it can be the internal connection of two elements or the interaction relationship between two elements. Unless otherwise clearly defined, ordinary technicians in this field can understand the specific meanings of the above terms in the present invention according to the specific circumstances.

[0021] In the present invention, the directions or positional relationships indicated by terms such as "upper", "lower", "bottom", "top", etc. are based on the directions or positional relationships shown in the accompanying drawings. They are relational words determined only for the convenience of describing the structural relationships of the various parts or elements of the present invention. They do not specifically refer to any part or element in the present invention and cannot be understood as limitations on the present invention.

[0022] like Figure 1 As shown, a low-pressure double-walled pipe fresh water purge system for a large container ship includes a methanol liquid supply system, which includes a methanol daily tank 1, the outlet of the methanol daily tank is connected to the inlet of a methanol supply pump 2, the outlet of the methanol supply pump is connected to the inlet of a heat exchanger 3, the outlet of the heat exchanger is connected to the inlet of a main engine methanol liquid supply double-walled pipe 4, the pipeline between the outlet of the heat exchanger and the inlet of the main engine methanol liquid supply double-walled pipe is sequentially connected with a first return pipe 5 and a first fresh water purge pipe 6, a first double-blocking valve 7 is provided between the first return pipe and the heat exchanger, a duplex filter is installed between the heat exchanger and the first double-blocking valve, a second double-blocking valve 8 is provided between the first return pipe and the first fresh water purge pipe, the outlet of the first return pipe is connected to the inlet of a purge discharge cabinet, a return valve 9 is provided on the first return pipe, a second fresh water purge pipe 10 is connected to the first return pipe between the return valve and the purge discharge cabinet 20, and the first fresh water purge pipe and the second A purge inlet valve 11 is provided on the fresh water purge pipe, the outlet of the main engine methanol liquid supply double-wall pipe is connected to the inlet of the purge and discharge cabinet, the outlet of the main engine methanol liquid supply double-wall pipe is provided with a purge valve 12 and a safety valve 13, the outer pipe of the main engine methanol liquid supply double-wall pipe is connected to the ventilation pipeline, the inlet of the ventilation pipeline is provided with an adjustable flow orifice plate 14, the outlet of the ventilation pipeline is provided with a gas detector 15, the pipeline between the methanol supply pump and the heat exchanger is connected to the second liquid return pipe 16, the second liquid return pipe is provided with a first conversion valve 17, the second liquid return pipe at the front end of the inlet of the first conversion valve is provided with a flow regulating valve 18, one outlet of the first conversion valve is connected to the inlet of the purge and discharge cabinet, and the other outlet is connected to the inlet of the methanol daily tank, the pipeline between the methanol supply pump and the methanol daily tank is provided with a second conversion valve 19, the outlet of the purge and discharge cabinet is connected to the second conversion valve, and the top of the methanol daily tank and the purge and discharge cabinet are provided with a vent pipe and an inert filling pipe.

[0023] The principle and use of the low-pressure double-walled pipe fresh water purge system of large container ships: When performing fresh water purge, close the first double isolation valve and the second double isolation valve, open the return valve on the first return liquid pipe, and then open the purge inlet valves on the first fresh water purge pipe and the second fresh water purge pipe, and use fresh water to purge the main engine methanol supply double-walled pipe and the first return liquid pipe. The mixture of methanol and fresh water after purge is collected in the purge discharge cabinet.

[0024] When the ship uses the fuel mode, open the first double isolation valve and the second double isolation valve, close the return valve on the first return pipe, the purge inlet valves on the first fresh water purge pipe and the second fresh water purge pipe, connect the inlet of the second conversion valve to the outlet of the purge and discharge cabinet, and transport the mixture of methanol and fresh water to the main engine methanol nozzle through the methanol supply system, and spray it into the main engine cylinder for mixed combustion. When the flow of the mixed liquid is too large, the flow regulating valve on the second return pipe is opened, and the outlet of the first conversion valve is connected to the purge and discharge cabinet to discharge the excess mixed liquid into the purge and discharge cabinet.

[0025] When the ship uses the methanol mode, when the flow of methanol is too large, the flow regulating valve on the second return liquid pipe opens, and the outlet of the first conversion valve is connected to the methanol daily tank to discharge the excess methanol into the methanol daily tank.

[0026] The above description shows and describes the preferred embodiments of the present invention. As mentioned above, it should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the invention concept described herein through the above teachings or the technology or knowledge of the relevant field. The changes and modifications made by those skilled in the art do not depart from the spirit and scope of the present invention, and should be within the scope of protection of the claims attached to the present invention.

Claims

1. Large container ship low-pressure double-walled pipe fresh water purge system, including methanol liquid supply system, characterized by: The methanol liquid supply system comprises a methanol daily tank, the outlet of the methanol daily tank is connected to the inlet of the methanol supply pump, the outlet of the methanol supply pump is connected to the inlet of the heat exchanger, the outlet of the heat exchanger is connected to the inlet of the main engine methanol liquid supply double-wall pipe, the pipeline between the outlet of the heat exchanger and the inlet of the main engine methanol liquid supply double-wall pipe is connected in sequence with a first return pipe and a first fresh water purge pipe, a first double-blocking valve is arranged between the first return pipe and the heat exchanger, a second double-blocking valve is arranged between the first return pipe and the first fresh water purge pipe, the outlet of the first return pipe is connected to the inlet of the purge discharge cabinet, and the first A liquid return valve is provided on a liquid return pipe, and the first liquid return pipe between the liquid return valve and the purge and discharge tank is connected to the second fresh water purge pipe, the outlet of the main engine methanol liquid supply double-wall pipe is connected to the inlet of the purge and discharge tank, and the pipeline between the methanol supply pump and the heat exchanger is connected to the second liquid return pipe. A first conversion valve is provided on the second liquid return pipe, one outlet of the first conversion valve is connected to the inlet of the purge and discharge tank, and the other outlet is connected to the inlet of the methanol daily tank. A second conversion valve is provided on the pipeline between the methanol supply pump and the methanol daily tank, and the outlet of the purge and discharge tank is connected to the second conversion valve.

2. The large container ship low-pressure double-walled pipe fresh water purge system according to claim 1 is characterized in that: A double filter is provided between the heat exchanger and the first double isolation valve.

3. The large container ship low-pressure double-walled pipe fresh water purge system according to claim 1 is characterized in that: The first fresh water purge pipe and the second fresh water purge pipe are both provided with a purge inlet valve.

4. The large container ship low-pressure double-walled pipe fresh water purge system according to claim 1 is characterized by: The outlet of the main engine methanol liquid supply double-wall pipe is provided with a purge valve and a safety valve.

5. The large container ship low-pressure double-walled pipe fresh water purge system according to claim 1, characterized in that: The outer tube of the main engine methanol liquid supply double-wall tube is connected to the ventilation pipeline, the inlet of the ventilation pipeline is provided with an adjustable flow orifice plate, and the outlet of the ventilation pipeline is provided with a gas detector.

6. The large container ship low-pressure double-walled pipe fresh water purge system according to claim 1, characterized in that: A flow regulating valve is provided on the second liquid return pipe at the front end of the inlet of the first conversion valve.

7. The large container ship low-pressure double-walled pipe fresh water purge system according to claim 1, characterized in that: The tops of the methanol daily tank and the purge and discharge cabinet are both provided with a vent pipe and an inerting pipe.

Images