Aerospace Technic and Technology

The requirements of international organizations in the field of environmental protection, reduction of heat losses and thermal emissions from the burning of organic fuels, increasing the efficiency and reliability of operation both stationary and ship's power plants (SPP) acutely raise the question of the development of complex cleaning technologies. The study aims to develop a system for complex exhaust gas cleaning of the internal combustion engine (ICE). For performing tasks in the technology of the proposed method were envisaged 6 stages of a technological process. It was established that the primary and decisive factor for solving the tasks in development a complex system for improving environmental indicators, reducing corrosion and heat emissions is the organization of the water-fuel emulsion (WFE) combustion process in the ICE based on sulfur fuels with water content of about 30% and using the effect of "microexplosions" drops of water. The conducted experimental studies have shown that when WFE is burned with water content W_r = 30 %, an equimolar (or almost this) NO₂: NO ratio necessary for activating the absorption properties of exhaust gases is created in gases. The results of studies have shown that under these conditions, passivation of the metal surface with a temperature below of dew point temperature of H₂SO₄ vapors takes place and therefore it becomes possible to significantly reduce the low-temperature corrosion of the condensation surface. This made it possible to install a low-temperature condensing heating surface with a surface temperature below the dew point of sulfuric acid vapor at the outlet of exhaust gas boiler after the ICE. Analysis of the experimental dates shows that: 1 m² of condensing surface absorbs 3.4 mg/m³ of NO_x and 0.89 mg/m³ of SO², which makes it possible to decrease the NO_x concentration by 1.55 times and SO₂ - in 1.5 times. There is a process of precipitation of toxic solid ash and soot particles: from 150...170 mg/m³ (at the outlet of ICE when WFE is burnt with W_r = 30 %) to 70...90 mg/m³ after the condensing surface. Consumption of water with alkaline properties decreases when NO_x, SO₂, CO₂ concentration is reduced in front of scrubbers. Reducing pollution of heating surfaces increases the cleaning period of EGB in 2.5 times. The developed complex system can be used to clean the ICE gases to the level recommended by IMO.

water-fuel emulsions; scrubber; utilization; pollution; low-temperature corrosion

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