Experimental Study Of Electron Beam Irradiation Of Flue Gas Desulfurization Process And Byproducts Collected

The flue gas desulphuration and denitration technology with electron beam irradiation (ab. EBP) is regarded as a promising method because it has advantages over traditional treatment for flue gas.There are some bottlenecks while EBP has been applied. The bottlenecks are as following: making high-power electron accelerator, optimizing technical parameters and collecting by-product.Experimental study on technical parameters of EBP and collecting by-product were carried out on the pilot plant of China Academy of Engineering Physics in Mianyang Sichuan province. The main experimental conclusions are summarized below:1. The main factors which affect deSO2 efficiency are following: adding ammonia stoichiometric (fNH3), electron beam's dose(dose), temperature(t) of flue gas in inlet of reactor and humidity(v%) of flue gas in inlet of reactor;2. The deSO2 efficiency can reaches 80% and the deNOx efficiency is more than 20%, which experimental conditions are described as following: adding ammonia stoichiometric f(NH3) is 0.80-1.0; and electron beam's dose is more than 4.5 kGy , and temperature of flue gas in inlet of reactor is about 65C; and humidity of flue gas in inlet of reactor is 8~12.5%(v);3. The characters of by-product are analyzed. Diameters of most powder are less than lurn, and average diameter of by-product powder is 0.1 um. The shape of by-product powder is roundness or near roundness;4. Different corona wires and collecting plates are investigated. Sawtooth shape corona wire has advantages such as low corona voltage, high spark voltage, wide running extent, big current density from single corona wire and strong adjustability to changing powder's concentration; 480C-type plate is used, and it has advantages as following: more collecting area, little powder of the plates returning flue gas and velocity of flue gas being more than 0.8 m/s.5. With the suitable corona wires and collecting plates, the most effective velocity that caused by force of electric field of by-product particles in 2m2 electrostatic precipitator is 0.279m/s; In the condition, the max of collecting efficiency is 99.2% when collecting by-product is used two electric fields electrostatic precipitator;6. A current power is better than a silicon-controlled-rectifier when they are used for the electrostatic precipitator. The current power has virtues such as: preventing from corona blocking out, low starting corona voltage, high operation voltage, avoiding corona wires being obesity, not easily forming arc in electric fields and good character of tracking condition.7. The first electric field with current power and the second electric field with silicon-controlled-rectifier are suitable to prevent from corona blocking out.Furthermore, methods of adding ammonia are researched. The pressure of spraying ammonia must be more than 0.3Mpa in order to avoid jamming in nozzle.