Study On The Combination Of Dedust,desulfuration And Byprodut Collection In Flue Gas By Pulse Corona Discharge

Pulse corona discharge induced plasma for SQ removal in flue gas is a novel tech- nology being developed. The combination of SO2 removal, fly ash precipitation and byproduct collection is one of the key problems to be solved in the tedmo1og~ which also simplifies the process of De-S02 and reduces the cost of De-S02. The paper experimentally and theoretically studied the problems. The following results were obtained. 1. The theory of parbcle charging in pulse corona discharge was established. The particle charging process was divided into two periods, the elecn charging in pulse discharge duration and the ion charging after the pulse discharge duration. A new mathematical model of the electron charging was established. Ion charging equations, including the field mechanism and diffusion mechanism, was obtained. The particle charge by electron and ion in pulse discharge was computed through rnuneric method respectively. The results showed that the particle charge induced by the supply of pulse with DC base was higher than by the single DC supply, especially for the fine particles. Under the condition of the computed exaDple, the particle charge increases by a ctor 1 for 02 p.m particles. 2. The particle transport in the electrohydrodynamic field of an electrostatic precipitator was analysed, thus it was concluded that the particle transport was an anisolropic planar turbulent transport process. A math model of turbulent transport was established on the base of the above analysis, and the particle density distribution was computed, then a new efficiency formula was put forward. The collection efficiency of the precipitator with pulse supply was computed. By the energization of pulse with DC, the collection efficiency could be improved, especially for the fine particles with diameter rner 2 p.ni 3. The combination of the SQ removal and the byproduct collection using pulse discharge was experimentally studied. There was some action for the bypaxiuct collection during the De-S02 in the reactor The collection efficiency of the byproduct which could be up to 63.lo/o inaeased with pulse peak voltage, pulse repetition rate, and the resident time of the gas. By adding DC base voltage to the reactor, the byproduct collection efficiency was remarkably improved, which also increased with the DC base voltage and the gas resident time. In the experiment, the highest efficiency was upto 95.1%. After adding the DC base voltage, the pulse voltage and current waveforms bad little change, while the pulse discharge was intensified, and the S02 removal efficiency was inaeasecL It can be concluded that the combination of the 502 removal and the byproduct collection is feasible by adding the DC base voltage to the reactor 4. The combination of 502 renxwal and precipitation using pulse discharge was experimentally studiecL fl~ SO2 removal rate induced by fly ash was less than 3%. The influence of fly ash on the pulse discharge characteristics and the SO2 removal rate was negligible. The water vapor in flue gas had obvious restraint on pulse discharge, but it could remarkably increase the S02 removal rate. fl~ cooperation of fly ash and water vapor was benefit to the SO2 removal. The fly ash could be effectively collected by pulse with DC base voltage supply, better than using DC supply only. The resident lime of ammonia in the field had influence on SO2 removal rate and (N1132S04 ratio in byproduct When the resident time is more than 3.3s, both the SO2 removal rate and (NH~SO4 ratio in...