Vessel two-stroke diesel engine exhaust gas recirculation system and control method

Abstract

The invention provides a vessel two-stroke diesel engine exhaust gas recirculation system and a control method. A work mode is a non-EGR (exhaust gas recirculation) mode and an EGR mode; when the vessel sails in a non-exhaust control region, the diesel engine works under the non-EGR mode, the exhaust gas exhausted from an exhaust manifold drives turbines to apply work so as to drive a gas compressor to compress air; the pressurized fresh air is cooled and dehumidified and then enters into the engine from a scavenging air receiver to participate in burning; when the vessel sails in an exhaust control region, the diesel engine works under the EGR mode, part of waste gas is led from the exhaust manifold and then flows to a one-way stop valve , then the waste gas is cooled and washed, so that the temperature is reduced, and the particles and SOx are removed; then, the exhaust gas is pressurized by an EGR fan and humidified by a drop catcher to mix with fresh air from the gas compressor in the scavenging air receiver, and then enters into an air cylinder to participate in burning; the NOx generation and exhaust amount of the engine are reduced, the Tier III standard related to NOx exhaust of IMO (International Meteorological Organization) can be satisfied.

Description

technical field [0001] The invention relates to a device for controlling discharge of exhaust gas pollutants from ships, and also relates to a control method for the device for controlling discharge of exhaust gas pollutants from ships. Specifically, it is a NOx emission control technology for a ship's two-stroke diesel engine to meet the regulations of the International Maritime Organization (IMO) on the discharge of ship's exhaust pollutants. Background technique [0002] With the development of the international shipping industry, exhaust emissions from ships have become the main source of air pollution in coastal areas, especially in ports. Among the gaseous emissions produced by marine two-stroke diesel engines, NOx accounts for a large proportion, and it is easy to form acid rain, acid fog and photochemical smog, and is one of the main acid gases that cause air pollution. [0003] IMO has imposed strict restrictions on NOx emissions from marine diesel engine exhaust. ...

AI Technical Summary

Problems solved by technology

The EGR system is aimed at four-stroke diesel engines for vehicles. For marine two-stroke diesel engines, since low-quality heavy oil is used, there are far more particles in the exhaust gas than four-stroke diesel engines that use light oil, so it is not suitable to use particle filters. In addition, low-pressure The EGR system increases the wear and tear on the compressor, and the ship uses central cooling, which is completely different from the vehicle air conditioning system

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