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
The effects of operating parameters on desulfurization efficiency of a dual-alkali FGD process in a rotating-stream-tray(RST)scrubber are investigated.A dimensionless factor,ε,is proposed in this study to predict des...The effects of operating parameters on desulfurization efficiency of a dual-alkali FGD process in a rotating-stream-tray(RST)scrubber are investigated.A dimensionless factor,ε,is proposed in this study to predict desulfurization efficiency of this dual-alkali FGD system.ε represents the desulfurization ability of a dual alkali FGD system,determined by five main operating parameters such as sodium ion concentration,ratio of absorbent flow rate to flue gas flow rate,pH value of absorbent solution,ratio of sulfate ion to total sulfur ion in absorbent solution,and sulfur dioxide concentration of inlet flue gas.The empirical expression for predicting desulfurization efficiency at different temperatures is obtained through the experimental study and theoretical calculation.It provides useful guide for engineering design.展开更多
A desulphurization retrofit project which adopted a patent technology with independent property rights, Datang International Douhe Power Plant's Unit No.8 has smoothly carried out 168-h trial operation in March th...A desulphurization retrofit project which adopted a patent technology with independent property rights, Datang International Douhe Power Plant's Unit No.8 has smoothly carried out 168-h trial operation in March this year. The project of the 200-MW coal-fired unit started to construct in September 2003,taking eighteen months completing construction and commission.The desulphurization system has used a limestone-gypsum wet desulphurization process and reached a desulphurization efficency of over 95%.展开更多
Background:Non-small cell lung cancer(NSCLC)has a poor prognosis with a low 5-year survival rate.Lung adenocarcinoma(LUAD)accounts for 50%.Facio-genital dysplasia-5(FGD5),a member of a subfamily of Rho GTPGDP exchange...Background:Non-small cell lung cancer(NSCLC)has a poor prognosis with a low 5-year survival rate.Lung adenocarcinoma(LUAD)accounts for 50%.Facio-genital dysplasia-5(FGD5),a member of a subfamily of Rho GTPGDP exchange factors,may be a good molecular biomarker for diagnosis and prognosis.Objective:To explore the clinical application of FGD5,the study was designed to investigate the prognosis value of FGD5 expression and its correlation with immune infiltrates in LUAD patients.Methods:Through the Wilcoxon signed-rank test and logistic regression,the correlation between clinical characteristics and FGD5 expression was analyzed.Kaplan-Meier plotter analysis,Cox regression,and a receiver operating characteristic(ROC)curve were constructed to evaluate the influence of FGD5 on prognosis.The function of FGD5 in lung cancer was analyzed using Gene set enrichment analysis(GSEA)and Single Sample Gene Set Enrichment Analysis(ssGSEA).Results:Compared to normal tissues,FGD5 was downregulated in LUAD.FGD5 may be a potential diagnostic and prognostic biomarker of lung cancer for its association with improved overall survival(OS),progression-free interval(PFI),and disease-specific survival(DSS)in LUAD.Results of functional analysis suggested that FGD5 was involved in the immune response for its association with immune infiltration.Conclusion:FGD5 may be a significant molecular biomarker for diagnosis and prognosis,presenting as an independent prognostic risk factor for LUAD.展开更多
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.
基金Supported by the National Hi-tech Researchand Development Program(863program)of China(No.2001AA642030-1)Key Research Project of Zhejiang Province(No.2004C23028)New Century Excellent Scholar Program of Ministry of Education of the People's Republic of China(No.NCET-04-0549)
文摘The effects of operating parameters on desulfurization efficiency of a dual-alkali FGD process in a rotating-stream-tray(RST)scrubber are investigated.A dimensionless factor,ε,is proposed in this study to predict desulfurization efficiency of this dual-alkali FGD system.ε represents the desulfurization ability of a dual alkali FGD system,determined by five main operating parameters such as sodium ion concentration,ratio of absorbent flow rate to flue gas flow rate,pH value of absorbent solution,ratio of sulfate ion to total sulfur ion in absorbent solution,and sulfur dioxide concentration of inlet flue gas.The empirical expression for predicting desulfurization efficiency at different temperatures is obtained through the experimental study and theoretical calculation.It provides useful guide for engineering design.
文摘A desulphurization retrofit project which adopted a patent technology with independent property rights, Datang International Douhe Power Plant's Unit No.8 has smoothly carried out 168-h trial operation in March this year. The project of the 200-MW coal-fired unit started to construct in September 2003,taking eighteen months completing construction and commission.The desulphurization system has used a limestone-gypsum wet desulphurization process and reached a desulphurization efficency of over 95%.
文摘Background:Non-small cell lung cancer(NSCLC)has a poor prognosis with a low 5-year survival rate.Lung adenocarcinoma(LUAD)accounts for 50%.Facio-genital dysplasia-5(FGD5),a member of a subfamily of Rho GTPGDP exchange factors,may be a good molecular biomarker for diagnosis and prognosis.Objective:To explore the clinical application of FGD5,the study was designed to investigate the prognosis value of FGD5 expression and its correlation with immune infiltrates in LUAD patients.Methods:Through the Wilcoxon signed-rank test and logistic regression,the correlation between clinical characteristics and FGD5 expression was analyzed.Kaplan-Meier plotter analysis,Cox regression,and a receiver operating characteristic(ROC)curve were constructed to evaluate the influence of FGD5 on prognosis.The function of FGD5 in lung cancer was analyzed using Gene set enrichment analysis(GSEA)and Single Sample Gene Set Enrichment Analysis(ssGSEA).Results:Compared to normal tissues,FGD5 was downregulated in LUAD.FGD5 may be a potential diagnostic and prognostic biomarker of lung cancer for its association with improved overall survival(OS),progression-free interval(PFI),and disease-specific survival(DSS)in LUAD.Results of functional analysis suggested that FGD5 was involved in the immune response for its association with immune infiltration.Conclusion:FGD5 may be a significant molecular biomarker for diagnosis and prognosis,presenting as an independent prognostic risk factor for LUAD.
