Purpose:
An experimental plasma-chemical system has been created in the National University of Shipbuilding in order to reduce the amount of carbon monoxides, nitrogen oxides, unburnt hydrocarbon and smoking in the marine and stationary energy plants’ exhaust gases.
Development Description:
The system includes 2 main functional elements: a plasma-chemical unit for the hydrocarbon fuel activation (liquid or gaseous) before it is delivered to the combustion chamber and its power source.
The plasma-chemical unit carries out the plasma activation of the hydrocarbon fuel with receiving of the gaseous products, which contain high-reacting components: reactive atoms of the O, H, radicals OH, CH, CH3, HO2, ions, and electron gas. The unit is an electroarc plasmachemical direct-flow circuitry reactor which has a plasma-forming air supply through the cyclonic ports and a cross jet-stream fuel supply into the plasma flow. Reagent pressure in the reaction chamber is 0,1...0,4 MPa, electric power consumption is 0,4...2,0 kilowatt. Constant current supply source with a steeply-falling external characteristic provides the initial electroarc interval breakdown and electroarc steady-state combustion in the plasma-chemical unit.
Plasma-chemical system allows to reduce the amount of CO and CH by 15...25 %, carbon black – by 20...35 %, nitric oxides – by 30 % in the exhaust gases.
The plasma-chemical unit carries out the supply to the preparation and the main fuel combustion zones of the high-reacting components, which appear as a result of the reaction of the activated fuel (in the amount of 3…5 % of the main fuel consumption) with an air-plasma jet-stream. The air, supplied to the unit, is being heated up to the plasma temperatures (2000…3000 К) thanks to the heat exchange with the electric arc, which is igniting between the electrodes. The unit is a fuel activation device, which consists of the sequentially located plasma generator and direct-flow reactor – a mixing chamber.
Reaction products, which have the abnormal temperatures, active component concentration levels, and turbulence levels, as for the usual combustion, are being delivered to the main combustion chamber. These products intensify the ignition and the air-fuel mixture combustion processes, enable the afterburning of the appeared carbon black particles and toxic incomplete combustion products, give the opportunity to combust weak mixtures, to extend the stability limit in 2-3 times.
Application Area:
The suggested low-emitting plasmachemical combustion technology can be used for both modernization of the existing gas turbine engines, internal combustion engines, steam and hot-water boilers, engineering fuelburning facilities, gas generators, and for the new-generation combustion chambers design.
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