Effect of gas composition on nitric oxide removal from simulated flue gas with DBD-NPC method

A new method for nitric oxide(NO)removal was developed by combining dielectric barrier discharge(DBD)and negative pulse corona(NPC).The effects of gas composition(O2,CO2,and H2 O)on NO removal were investigated with this method,and the effect of alcohols(methanol and ethanol)addition on NO removal was also investigated as well as the reaction mechanisms to enhance the NO removal efficiency.The experimental results showed that O2,CO2,and H2 O had obvious inhibition effects on NO removal,and the negative effects were in the following order:O2>CO2>H2 O.The addition of methanol or ethanol in the reaction system could mitigate the negative effects of O2,CO2 and H2 O on NO removal,and also eliminated the production of N02.The positive effect of alcohols addition with DBD-NPC denitration method was also validated in the simulated flue gas,in which the NOx(NO,NO2)was mainly converted into N2.

Investigations on removal of SO_2 from flue gas by aerosol formation in pulsed corona discharge process

The removal of SO 2 from flue gas by pulsed corona discharge in presence of ammonia was experimentally investigated. The results showed that the SO 2 removal mainly depends on thermal reaction of SO 2 with NH 3 and enhancements of 0%—25% by pulsed corona discharge in the range of the specific energy 0—5 Wh/Nm 3. The aerosol mass concentration, mainly composed of ammonium sulfate, increased with specific energy dissipated into the reactor. With an initial concentration of 2000—2100 ppmv SO 2 and energy consumption of 3 Wh/Nm 3, when a stoichiometric amount of ammonia is injected, the removal efficiency of SO 2 and percentage of ammonium sulfates in reaction products are all ≥80%. The collection efficiency of the reactor for aerosol is about 74% at a flue gas temperature of 60 to 65℃ and a water vapor content of 9% to 11% volume.

Improving the energy efficiency of surface dielectric barrier discharge devices for plasma nitric oxide conversion utilizing active flow control

Improving energy efficiency in plasma NO removal is a critical issue.When the surface dielectric barrier discharge(SDBD)device is considered as a combination of multiple plasma actuators,the induced plasma aerodynamic effect cannot be ignored,which can affect the mass transfer,then affect the chemical reactions.Five SDBD devices with different electrode arrangements are studied for NO conversion.They correspond to different flow patterns.We find that the energy efficiency in an SDBD device with a common structure(Type 1)is 28%lower than that in SDBD devices with a special arrangement(Types 2–5).Two reasons may explain the results.First,fewer active species are produced in Type 1 because the development of discharge is hindered by the mutually exclusive electric field forces caused by the symmetrically distributed charged particles.Second,the plasma wind induced by the plasma actuator can enhance the mass and heat transfer.The mixing of reactants and products is better in Types 2–5 than Type 1 due to higher turbulence kinetic energy.

低压省煤器在电站锅炉中的应用

针对排烟损失大的问题 ,某些电厂在电除尘器出口加装低压省煤器 ,用来加热凝结水或热网补水 ,从而吸收烟气热量。实际测试结果表明 。

提高锅炉供热效率的途径

通过深入分析影响燃气锅炉效率的关键因素,结合青海油田基地的供热能源利用现状,针对特定油田天然气组分情况,指出了提高锅炉供热效率的途径。认为从源头上大力降低现有供热系统的能耗,具有巨大的节能空间及潜在价值。

Study on the treatment of spraying wastewater from coal-fired flue gas by using discharge free radicals

The coal-fired flue gas spraying wastewater is a kind of refractory mixed wastewater with poor biodegradability.In this study,the degradation of model coal-fired flue gas spraying wastewater was studied by using discharge free radicals produced by double-dielectric barrier discharge.The degradation rate of pollutants,chemical oxygen demand removal rate and other indicators were detected,and the influence of different conditions on the degradation effect was analyzed.The optimal parameters are as follows:residence time 120 min,input power 170.0 W,initial pH value 3.79,and aeration rate 1.8 mL/min.The initial concentrations of acetone,formaldehyde,chloroform,benzene and toluene were 100,100,100,and 100 mg/L,respectively.Furthermore,it is proved that the discharge area is independent of the degradation rate.Through the analysis of the mechanism,it is found that·OH is an important factor affecting the degradation rate of pollutants in model coal-fired flue gas spraying wastewater.

浅谈立式旋风炉脉冲燃气吹灰器的应用

应用先进有效吹灰器,经常对受热面吹扫,保持受热面清洁干燥,能较好地避免受热面结渣、积灰、腐蚀,保持有效传热,降低排烟温度,减少排烟热损失,提高锅炉效率,具有显著的经济效益。

A Theoretical Investigation of Efficiency Enhancement in Thermal Power Plants

The need to operate a boiler efficiently in today’s environment is at the top of many plant owners and operators lists. Unfortunately, operating a boiler efficiently and meeting local emission regulations do not always go hand in hand. However, advances in boiler system design and technology have made this a much more achievable task. The potential for energy improvements and cost savings is substantial when considered that most boilers operating today are performing at efficiencies that are less than 70 percent. The performance calculation and rectification measures are essential for performance evaluation and efficiency enhancement. Since the efficiency decreases from time to time it is required to find out the losses occurring in boiler using proper methodology. The environmental issues and economy are the secondary factors to be considered after finding the losses. Due to increase in fuel price and demand in more energy requirement in everyday life, proper utilization of materials and resources are necessary. This present deals with the aim of estimating the heat losses occurring in thermal power plant boilers and hence finding suitable ways for reducing it, hence allowing plants to achieve more performance, sustainability and cost-effective maintenance operation of a steam system.