Rolling Decision Model of Thermal Power Retrofit and Generation Expansion Planning Considering Carbon Emissions and Power Balance Risk

With the increasing urgency of the carbon emission reduction task,the generation expansion planning process needs to add carbon emission risk constraints,in addition to considering the level of power adequacy.However,methods for quantifying and assessing carbon emissions and operational risks are lacking.It results in excessive carbon emissions and frequent load-shedding on some days,although meeting annual carbon emission reduction targets.First,in response to the above problems,carbon emission and power balance risk assessment indicators and assessment methods,were proposed to quantify electricity abundance and carbon emission risk level of power planning scenarios,considering power supply regulation and renewable energy fluctuation characteristics.Secondly,building on traditional two-tier models for low-carbon power planning,including investment decisions and operational simulations,considering carbon emissions and power balance risks in lower-tier operational simulations,a two-tier rolling model for thermal power retrofit and generation expansion planning was established.The model includes an investment tier and operation assessment tier and makes year-by-year decisions on the number of thermal power units to be retrofitted and the type and capacity of units to be commissioned.Finally,the rationality and validity of the model were verified through an example analysis,a small-scale power supply system in a certain region is taken as an example.The model can significantly reduce the number of days of carbon emissions risk and ensure that the power balance risk is within the safe limit.

Environmental consequences of an ultra-low emission retrofit in coal-fired power plants from a life cycle perspective

To make coal-fired power generation more environmentally friendly,China has initiated a series of ultra-low emission ret-rofits to the air pollution control(APC)system of the existing power plants.In this study,a life cycle assessment(LCA)is conducted to analyze the environmental net benefits for the typical ultra-low emission retrofit of a 1000 MW power plant.The key processes,substances,and APC devices are verified and discussed.The results confirm that the retrofit effectively decreases the environmental stress of acidification potential(AP),eutrophication potential(EP),and photochemical ozone creation potential(POCP)by 69%-79%,which can be attributed to significantly reduced emissions at the stack.However,the retrofit has also increased other impact categories by 24%-79%,primarily due to the consumption of additional elec-tricity and adsorbents.The retrofit of selective catalytic reduction,electrostatic precipitator(ESP),and wet limestone flue gas desulfurization devices has a dominant effect on the impacts of EP,human toxicity potential(HTP),and AP.A newly installed wet ESP shows some environmental benefits(only for AP),but causes considerable burdens,in particular for the investigated impact categories global warming potential(GWP),marine aquatic ecotoxicity(MAETP),and abiotic depletion fossil(ADP fossil).The obtained results indicate that the hidden environmental consequences,which are associated with the production of energy and materials,need to be examined more comprehensively to inform the development of ultra-low emission technologies and strategies effectively.

Angle Scattering Method for Soot Concentration Measurement under Ultra-Low Emissions Condition

Aiming at the problem of soot concentration measurement under ultra-low emission conditions,a forward small angle soot concentration measurement method is proposed.Taking a typical boiler emission of 0.1μm-3.0μm bimodal distribution soot as an object,the particle scatter simulation calculation under different parameters is carried out,and the influence of detection angle and particle size on the angular scatteringmeasurement of ultra-low emission soot is analyzed.The influence of detection angle and particle size on the angular scatteringmeasurement of ultra-lowemission soot is analyzed.Preferably,thewavelength of incident light is 650 nm,and the forward detection angle parameter is 15◦for the design of forward small angle soot concentration measurement system.An experimental system for measuring soot with standard concentration is built.Experiments of particle concentration measurement of 1.0μm and 3.0μm under ultra-low emission conditions are carried out.The results show that the average deviation of soot concentration measurement is less than 0.10 mg/m3 under the condition of ultra-low emission by using 15◦of forward detection,which provides an effective way for monitoring ultra-low emission soot concentration in coal-fired power plants.

Re-understanding and Thinking about Environmental Impact of Coal-fired Power Plants under Ultra-low Emission

From the perspective of development background,concepts and related policies of ultra-low emission,according to work practice,some issues and difficulties that need to be paid attention to in the environmental impact assessment of ultra-low-emission thermal power projects were discussed from the aspects of evaluation criteria,evaluation grade and scope,pollution control technical lines,environmental benefit accounting,and total emission control,and corresponding recommendations were put forward.

Distribution and bioavailability of mercury in size-fractioned atmospheric particles around an ultra-low emission power plant in Southwest China

Ultra-low emission(ULE)technology retrofits significantly impact the particulate-bound mercury(Hg)emissions from coal-fired power plants(CFPPs);however,the distribution and bioavailability of Hg in size-fractioned particulate matter(PM)around the ULE-retrofitted CF-PPs are less understood.Here,total Hg and its chemical speciation in TSP(total suspended particles),PM_(10)(aerodynamic particle diameter≤10μm)and PM_(2.5)(aerodynamic particle diameter≤2.5μm)around a ULE-retrofitted CFPP in Guizhou Province were quantified.Atmospheric PM_(2.5)concentration was higher around this ULE-retrofitted CFPP than that in the intra-regional urban cities,and it had higher mass Hg concentration than other sizefractioned PM.Total Hg concentrations in PM had multifarious sources including CFPP,vehicle exhaust and biomass combustion,while they were significantly higher in autumn and winter than those in other seasons(P<0.05).Regardless of particulate size,atmospheric PM-bound Hg had lower residual fractions(<21%)while higher HCl-soluble fractions(>40%).Mass concentrations of exchangeable,HCl-soluble,elemental,and residual Hg in PM_(2.5)were higher than those in other size-fractioned PM,and were markedly elevated in autumn and winter(P<0.05).In PM_(2.5),HCl-soluble Hg presented a significantly positive relationship with elemental Hg(P<0.05),while residual Hg showed the significantly positive relationships with HCl-soluble Hg and elemental Hg(P<0.01).Overall,these results suggested that atmospheric PM-bound Hg around the ULE-retrofitted CFPP tends to accumulate in finer PM,and has higher bioavailable fractions,while has potential transformation between chemical speciation.

基于暴雨洪水管理模型的工业厂房海绵城市改造设计优化——以天津卷烟厂技改项目三期工程为例

以天津卷烟厂技改项目三期工程为研究对象,对项目场地内的普通绿化、普通下凹式绿地以及碳纤维模块绿地分别进行人工注水试验,并根据试验数据对不同构造条件下土壤层的孔隙率、产水能力、枯竭点及渗透系数等模型参数进行率定。通过暴雨洪水管理模型(SWMM)的模拟分析,以项目改造前的场地绿化雨水径流为对照样本,研究在不同降雨强度和降雨历时的条件下,普通下凹式绿地和采用碳纤维模块的下凹绿地对暴雨径流的影响。模拟结果显示,设有碳纤维模块的下凹绿地其产水能力及渗透系数均有提升,对雨水径流的控制能力更强,项目优化后的海绵城市效益相对更好,可为其他同类型的改造工程提供海绵城市设计参考。

西安地区典型博物馆建筑低碳化改造研究——以陕西历史博物馆为例

为解决博物馆建筑室内舒适度与碳排放难以权衡的改造问题,从建筑性能提升和可再生能源利用两个方面对西安地区典型博物馆建筑进行低碳化改造。在建筑性能提升方面,利用拉丁超立方采样技术,基于多维设计参数形成的能耗模拟数据库,分析建筑能耗与参数设计的关系,结合TOPSIS方法寻求评估指标的最优解。此外,还进行了变量敏感性分析,为决策提供客观和科学的支持。在可再生能源利用方面,提出了西安地区太阳能光伏发电的最佳倾角和方位角。通过陕西历史博物馆的案例研究,结果显示改造后的博物馆舒适度提升了1.43%,总碳排放量、供暖碳排放量、供冷碳排放量分别降低了57.9%、70.9%、39.8%,屋顶光伏板年发电量可满足建筑性能提升后94%的能源需求。

住宅建筑超低能耗改造设计及碳排放对比研究

近年来,超低能耗建筑和近零能耗建筑获得了越来越多的关注。随着国家由增量转存量的建筑节能目标转变,针对住宅建筑的节能改造呈现出巨大的潜力。以寒冷地区典型住宅建筑为案例,进行超低能耗节能改造设计及碳排放测算对比研究。设置30组外墙保温方案、30组屋面保温方案、4组外窗类型方案进行模拟,并基于模拟结果采用敏感性分析进行方案比选。相较基准建筑和改造前建筑,综合最优方案的节能率分别为57.1%、72.1%。采用碳排放因子法对改造前建筑及58组模拟方案进行碳排放测算,可知改造后建筑运行阶段的碳排放量可降低84.2%,并基于测算结果对改造设计方案进一步优化,为既有住宅的超低能耗节能改造提供理论与实践参考。

Multi-process and multi-pollutant control technology for ultra-low emissions in the iron and steel industry

The iron and steel industry is not only an important foundation of the national economy,but also the largest source of industrial air pollution.Due to the current status of emissions in the iron and steel industry,ultra-low pollutant emission control technology has been researched and developed.Liquid-phase proportion control technology has been developed for magnesian fluxed pellets,and a blast furnace smelting demonstration project has been established to use a high proportion of fluxed pellets(80%)for the first time in China to realize source emission reduction of SO_(2)and NO_(x).Based on the characteristics of high NO_(x)concentrations and the coexistence of multiple pollutants in coke oven flue gas,low-NO_(x)combustion coupled with multi-pollutant cooperative control technology with activated carbon was developed to achieve efficient removal of multiple pollutants and resource utilization of sulfur.Based on the characteristics of co-existing multiple pollutants in pellet flue gas,selective non-catalytic reduction(SNCR)coupled with ozone oxidation and spray drying adsorption(SDA)was developed,which significantly reduces the operating cost of the system.In the light of the high humidity and high alkalinity in flue gas,filter materials with high humidity resistance and corrosion resistance were manufactured,and an integrated pre-charged bag dust collector device was developed,which realized ultralow emission of fine particles and reduced filtration resistance and energy consumption in the system.Through source emission reduction,process control and end-treatment technologies,five demonstration projects were built,providing a full set of technical solutions for ultra-low emissions of dust,SO_(2),NO_(x),SO_(3),mercury and other pollutants,and offering technical support for the green development of the iron and steel industry.

典型气候区既有居住建筑节能改造策略研究

利用PKPM软件对夏热冬冷、夏热冬暖及温和地区某典型居住建筑的典型工况进行模拟分析,计算既有建筑改造前后的节能率及经济效益,并提出了以单位建筑面积碳排放经济成本为指标进行碳排放分析。研究结果显示,夏热冬冷地区建议进行屋面和外墙综合改造;夏热冬暖地区以屋面和低SHGC外窗作为综合节能改造的重点;温和地区则建议进行屋面和高SHGC外窗改造。

炼厂燃气动力炉富氧燃烧技术改造方案及性能分析

通过实验研究和理论分析,对燃气动力炉富氧燃烧污染物排放与燃烧特性进行研究,分析氧气体积分数对锅炉燃烧性能的影响。结果表明:当氧气体积分数为28%~30%时,炉膛温度基本与空气助燃工况相当,而炉膛的传热效率则随氧体积分数的升高而上升。氧体积分数升高可以提升燃烧效率,降低烟气中CO的排放,同时,富氧燃烧通过屏蔽氮源及控制炉温可大幅降低NO_(x)质量浓度。在70 kW热水锅炉上测试结果表明,当燃气量为3 m^(3)·h^(-1)、富氧助燃氧气体积分数大于28%时,锅炉排烟中NOx质量浓度小于20 mg·m^(-3),CO质量浓度小于80 mg·m^(-3),排烟中CO_(2)体积分数为32%,水体积分数为63%,该烟气经脱水后,CO_(2)体积分数可达到95%以上,满足CO_(2)用于驱油的指标要求。

一种城市功能照明自愿性减排量核定方法——以南京市路灯节能改造项目为例

以南京市路灯节能改造项目为例,从“新建”和“改造”两个方面介绍了一种城市功能照明设施自愿性减排量的核定方法。该方法以“自愿性减排量=基准线排放量-减碳项目实施后排放量”为核心公式,通过“项目边界核定”“基准线排放量核定”和“减碳项目实施后排放量核定”等多个步骤计算得出核定结果,为城市照明节能改造项目的减排量核算提供了一种参考模型。

小单元气动振打电除尘技术研究及应用

双碳目标下,燃煤机组负荷适应性和提效改造正成为行业改造升级的主流方向。在此背景下,分析了电除尘出口槽型板粉尘逃逸原理,研发了小单元气动振打电除尘技术,通过对电除尘器出口槽型板进行小单元划分,并设置单独的振打清灰机制,实现了收尘功能,并解决了影响电除尘二次扬尘的技术瓶颈,显著提升了电除尘器的除尘效率。以江苏镇江电厂某630 MW机组电除尘器改造为例,对比了不同负荷下的性能,并在燃用难以静电除尘的劣质煤种情况下进行了试验。试验结果显示:电除尘提效成果显著。

产能置换情景下钢铁企业防护距离影响研究

基于辽宁省某钢铁企业的污染源排放数据,建立现状和产能置换实施后两种情景,利用CALPUFF模型模拟了两种情景下该钢铁厂各类污染物排放对厂区周边大气环境防护距离和卫生防护距离设置的影响。结果显示:钢铁企业产能置换项目的实施对各主要污染物的减排效果明显,各主要污染物中颗粒物、SO2、NOX分别减排约53.4%、16.2%、50.9%。产能置换项目实施后,相较于现状情景下,钢铁厂周边区域的大气防护距离和卫生防护距离均得到了减少。

A systematic strategy for multi-period heat exchanger network retrofit under multiple practical restrictions

A systematic strategy for retrofit of the multi-period heat exchanger network （HEN） on the basis of the multi- objective optimization is developed. In this three-stage procedure, a simplified multi-objective optimization model of the multi-period lIEN is first established and then solved to target the retrofit, aiming to minimizing the total annual cost and total annual CO2 emissions. The obtained Pareto front represents series of retrofit targets under different emission limitations, from which the most desirable one can be selected. The matching of the existing and the required heat exchangers is further implemented to finalize the retrofit, which will meet the practical retrofit requirements and matching restrictions. The application of the proposed procedure is illustrated through a case study of a HEN in a vacuum gas oil hydro-treating unit.

MBBR用于某CAST工艺污水处理厂提标改造的效能及碳排放分析

通过对比分析浙江省某污水处理厂提标改造前后的运行数据,研究移动床生物膜反应器(MBBR)工艺镶嵌循环式活性污泥工艺(CAST)对系统污染物去除效果以及电耗、药耗、物耗对碳排放量的影响。结果表明:MBBR工艺强化了系统的生物脱氮除磷效果,提高了系统的抗冲击负荷能力。改造后污水处理厂出水COD与NH_(3)-N、TN、TP浓度的全年平均值分别为13.7、0.2、4.3、0.05 mg/L,均能稳定达到浙江省地方标准DB 33/2169—2018《城镇污水处理厂主要水污染物排放标准》要求。改造后污水处理厂内部电耗分布无明显变化,吨水电耗增加19%,而全年消耗的外加碳源、混凝剂、消毒剂均不同程度下降,吨水药剂总用量减少44%。改造后污水处理厂碳排放量由1.04 kg/m^(3)降至0.79 kg/m^(3),处理过程产生的CH_(4)和物耗对污水处理厂整体碳排放的贡献较大。

中国既有公共建筑节能工作的困境与突围

基于我国“十四五规划”中对节能环保工作的强调,以及“30·60”双碳目标,国内各领域的节能减排工作愈发紧迫。近年来,建筑领域的能耗与碳排放量一直居高不下。据统计,2018年我国公共建筑的能耗总量达到3.83亿tce,约占到我国总能耗的8.30%,且仍在持续增长。因此,既有公共建筑节能改造工作需快速推进,该过程中也面临机遇与挑战。通过广泛的调研、文献综述、数据采集等方式,整理并展示了我国既有公共建筑面积及用能的现状与趋势,分析了该领域节能工作面临的困境和机遇;结合我国当前情形,从意识、实践、体系三个层面为国内既有公共建筑节能工作提出建议。

既有建筑零碳改造路径探索与评价

建筑领域实施低碳、零碳发展路径有助于早日实现“双碳”目标,践行“一带一路”的绿色发展理念。以北京金隅怀柔兴发科技园区及园区内一既有建筑零碳改造工作为例,确定了园区整体的低碳实施路径与零碳建筑改造技术方案。园区通过产业低碳、建造低碳、运行低碳3个方面实现低碳目标。既有建筑通过超低能耗技术(建筑本体节能)、光储直柔等可再生能源应用(碳替代)与绿植碳汇(碳补偿)技术,实现建筑运行阶段和全生命周期的零碳乃至负碳。既有建筑零碳改造后运行阶段一次能源总需求为-71.3 kW·h/(m^(2)·a),年单位建筑面积碳排放强度-14.2 kgCO_(2)e/(m^(2)·a),建筑全生命周期(50年)可减少碳排放量508.48 tCO_(2)e。研究内容为“一带一路”沿线国家实施建筑绿色低碳建造提供重要的理论参考和实践支撑。

Combustion and NO_(x)Emission Characteristics of Coal Slime Solid Waste at Different Feeding Positions

The NO_(x)emission of coal slime burned in circulating fluidized bed(CFB)boilers could hardly meet the increasingly strict standards in China.Feeding coal slime from the top of furnace led to uneven combustion in furnace and cyclones,short residence time and overheated tail heating surface.The effects of feeding positions on the combustion uniformity and pollutant emission characteristics of coal slime were studied.The experimental results showed that the coal slime combustion was more uniform when feeding from the front wall and longer residence time was conducive to the control of NO_(x)emission.When the boiler temperature and excess air ratio were almost identical,the initial NO_(x)emissions were 45.0 mg·m^(−3)and 70.7 mg·m^(−3)when feeding from the front wall and the top of furnace,respectively;the NO_(x)emission was cut down 36.35%when feeding from the front wall,successfully meeting the ultra-low NO_(x)emission standard of China.The adoption of feeding from the front wall greatly reduced the original emission of NO_(x);the operation costs in the practical applications were saved to a large extent.

Practice on Ultra-low Emission and Energy Efficient Technologies in Coal-fired Power Plants

Restructuring of China's energy mix is accelerating due to factors such as energy security,economic cost,climate change and environmental pressure.Efficient and clean utilization of coal-generated power therefore plays an increasingly important role in solving energy and environmental problems in China.Coal-fired power plants,with Shenhua Guohua Sanhe as one of the pioneers,followed trend of this era and adopted multiple ultra-low emission and energy efficient technologies,striving to be an industry leader in environmental protection,profitability and innovation.As a result,coal-fired power plants have seen ultra-low emissions of air pollutants and record-high energy efficiency,opening up a new era of more efficient and cleaner coal generation.By the end of 2015,Shenhua Group had had 45 ultra-low emission coal units,providing strong support for implementing of the national policy on ultra-low emission and energy efficient retrofit of coal-fired power plants across China.