This paper introduces present state of industrialization development in flue gas desulfuration, including technological selection, state of design and contracting capability, localization of equipment, etc. in China. ...This paper introduces present state of industrialization development in flue gas desulfuration, including technological selection, state of design and contracting capability, localization of equipment, etc. in China. It points out main problems currently existed and presents proposals on promotion of desulfuration technology with selfowned intellectual property right, perfection of demonstrative projects and pushing forward localization of desulfuration equipment.展开更多
The Ontario Hydro Method (OHM) recommended by the United States Environmental Protection Agency (EPA) was used to determine mercury speciation in the combustion flue gas across wet FGD systems. Four coal-fired uni...The Ontario Hydro Method (OHM) recommended by the United States Environmental Protection Agency (EPA) was used to determine mercury speciation in the combustion flue gas across wet FGD systems. Four coal-fired units with wet FGD systems were chosen to evaluate mercury speciation and mercury removal efficiencies through these wet FGD systems. Chlorine content in coal had been suggested as a main factor that affects mercury speciation in flue gas. It is shown that the higher the chlorine concentration in coal is, the higher the percentage of oxidized mercury (Hg2+) is removed in wet FGD systems, which can increase overall mercury removal efficiencies through wet FGD systems. The selective catalyst reduction (SCR) system has a function of oxidizing ele- mental mercury (Hg0) to oxidized mercury. A higher percentage of oxidized mercury in the total vapor mercury at the FGD inlet is observed when SCR is in service. Therefore, higher overall mercury removal efficiencies through wet FGD are attained. Because of different wet FGD operating conditions, there are different mercury removal efficiencies in different units. Elemental mercury reemission took place when a fraction of oxidized mercury absorbed in the slurry is reduced to elemental mercury, and Hg2+ is reemitted from stack, which results in decreases in mercury removal efficiencies through wet FGD systems.展开更多
文摘This paper introduces present state of industrialization development in flue gas desulfuration, including technological selection, state of design and contracting capability, localization of equipment, etc. in China. It points out main problems currently existed and presents proposals on promotion of desulfuration technology with selfowned intellectual property right, perfection of demonstrative projects and pushing forward localization of desulfuration equipment.
文摘The Ontario Hydro Method (OHM) recommended by the United States Environmental Protection Agency (EPA) was used to determine mercury speciation in the combustion flue gas across wet FGD systems. Four coal-fired units with wet FGD systems were chosen to evaluate mercury speciation and mercury removal efficiencies through these wet FGD systems. Chlorine content in coal had been suggested as a main factor that affects mercury speciation in flue gas. It is shown that the higher the chlorine concentration in coal is, the higher the percentage of oxidized mercury (Hg2+) is removed in wet FGD systems, which can increase overall mercury removal efficiencies through wet FGD systems. The selective catalyst reduction (SCR) system has a function of oxidizing ele- mental mercury (Hg0) to oxidized mercury. A higher percentage of oxidized mercury in the total vapor mercury at the FGD inlet is observed when SCR is in service. Therefore, higher overall mercury removal efficiencies through wet FGD are attained. Because of different wet FGD operating conditions, there are different mercury removal efficiencies in different units. Elemental mercury reemission took place when a fraction of oxidized mercury absorbed in the slurry is reduced to elemental mercury, and Hg2+ is reemitted from stack, which results in decreases in mercury removal efficiencies through wet FGD systems.