Using the heat of recirculation gases of the ship main engine by an ejector refrigeration machine for intake air cooling

D Konovalov,M Pyrysunko,M Radchenko,R Radchenko

doi:10.15673/ret.v55i1.1346

Abstract

One of the promising ways in environmentalizing marine internal combustion engines is the neutralization of harmful substances in exhaust gases through particular gas recirculation (EGR-technology). However, the use of such techniques conflicts with the engine's energy efficiency. In the work presented, the scheme-design solution of the exhaust gas recirculation system with using the heat of recirculation gases by an ejector refrigeration machine for cooling the air at the intake of ship's main engine is proposed. The effect of using the heat of recirculation gases for cooling the air at the intake of the engine is analyzed taking into account the changing climatic conditions for a particular vessel's route line. It is shown that the use of an ejector refrigeration machine reduces the air temperature at the entrance of the main engine by 5-15 ° С, which reduces the specific fuel consumption by 0.5-1.5 g/(kW∙h). This reduces emissions of harmful substances when the engine is running with recirculation of gases, in particular, NOx by 30-35%; SOx by 10-12%.

Highlights

It is during the operation of internal combustion engine, due to chemical pollution by toxic substances contained in the exhaust gases, that the greatest harm is caused, and the most sensitive environmental impact comes from ship power plants, in which the main source of energy is internal combustion engines
The calculation was made for the following initial data: the performance characteristics of the main engine – engine load – NMCR = 90 %; power – Nе = 19656 kW; speed – nе = 80.1 rpm; specific fuel oil consumption (SFOC) – gе = 169.8 g/(kWh); exhaust gas recirculation system (EGR) – bypass with scrubber and gas cooler, responsible for Tier III environmental conditions
The bypassing recirculation system works as follows: exhaust gases from 10 to 40 % in quantity are fed to the scrubber through the valve, where they are partially cooled and cleaned when water is sprayed with special nozzles

Summary

Introduction

The internal combustion engines occupy a leading place as an energy source (thermal, mechanical, electrical) It is during the operation of internal combustion engine, due to chemical pollution by toxic substances contained in the exhaust gases, that the greatest harm is caused, and the most sensitive environmental impact comes from ship power plants, in which the main source of energy is internal combustion engines. The formation of such harmful gases, such as carbon dioxide CO2, nitrogen oxides NOx, carbon monoxide CO, sulfur oxides SOx, etc., depends on the organization of work processes in the internal combustion engine. The use of such technologies is in conflict with the energy efficiency of the internal combustion engine, because the measures to reduce emissions require additional costs

Objectives

Methods

Results

Conclusion