水泥企业原料碳酸盐分解CO_2排放量核算研究

在现有水泥企业CO_2排放核算方法基础上,分析水泥生产企业碳酸盐分解CO_2排放核算的难点,并通过研究水泥生产企业熟料中非碳酸盐分解CaO及MgO的来源,结合现有全国碳交易水泥生产企业CO_2排放核算核查技术要求,提出了计算熟料中非碳酸盐分解CaO及MgO含量的"三步计算法",对全国碳交易水泥企业CO_2排放核算和核查具有一定的指导作用。     

水泥行业湿法脱硫技术

<正>0引言水泥工业对大气环境产生影响的废气主要包括粉尘、SO_2、NOx、CO_2、HF等,其中SO_2是由生料、燃料中含硫成品在燃烧过程中产生的。工业生产中产生的SO__2被排放到大气中,会对环境造成严重危害。当SO_2溶于水中,会形成亚硫酸。若把亚硫酸进一步在PM2.5存在的条件     

水泥窑热生料高效脱硫技术的应用

详细介绍了SO2形成机理、热生料高效脱硫采取的措施及效益分析。实践证明，水泥窑热生料高效脱硫技术，可以有效降低SO2排放，而且投资、运行成本低，对窑系统影响小，在原燃料稳定时，可以实现低于50 mg/Nm3的排放控制。     

页岩气藏与无水压裂介质CO_2源汇匹配研究

我国是世界上最大的CO_2排放国,CO_2的大量排放致使面临巨大的环境压力。利用CO_2开采页岩气,不仅可以减少我国的CO_2排放量,还可实现CO_2的资源化利用。为研究我国CO_2排放源与页岩气藏的分布与现状,通过查阅年鉴和文献,计算了火电、钢铁和水泥等行业的CO_2排放量以及在全国的分布,并对比页岩气藏的分布,简析了两者的地域分布匹配情况。分析结果显示:页岩气藏分布周围火电行业CO_2排放量占全国火电行业总排放量的70%,钢铁行业CO_2排放量占全国钢铁行业总排放量的75%,水泥行业CO_2排放量占全国水泥行业总排放量的65%以上。在页岩气藏分布地区CO_2排放源分布比较集中,保证了无水压裂介质CO_2来源。我国页岩气藏与工业CO_2排放源的分布地域匹配良好,采用CO_2作为压裂介质开采页岩气具有良好的发展前景。     

水泥工业CO_2过程捕集技术研究进展

水泥工业CO_2排放量约占全球CO_2总排放量的5%,CO_2捕集利用及储存是水泥工业最有减排潜力的技术。围绕水泥生产过程CO_2捕集,本文重点讨论了全氧燃烧技术、分解炉全氧燃烧技术、直接分离反应技术在水泥工业的研究及应用进展。阐述了全氧燃烧捕集CO_2的技术方案,分析了全氧燃烧对传统水泥生产过程—生料分解、熟料煅烧、熟料冷却的影响规律,并介绍了全氧燃烧技术的应用进展。对两种分解炉全氧燃烧技术路线进行了对比分析,详细介绍了分解炉全氧燃烧的工业化试验结果。分析了直接分离反应技术捕集CO_2的工作原理,介绍了捕集水泥生产CO_2的LEILAC工业计划。本文对比分析了全氧燃烧技术、分解炉全氧燃烧技术、直接分离反应技术在CO_2捕集效率、改造与投资成本、工业化应用等方面的差异,并对我国水泥工业CO_2过程捕集技术进行了介绍。     

Solidia气硬性水泥混凝土的性能和商品化

正2014年全世界消耗水泥约42亿吨,混凝土超过200亿吨,是地球上消耗最多的材料。按每吨普通硅酸盐熟料(简称PC熟料)产生的CO_2为810kg计算,CO_2排放总量约30亿吨。近些年来,为降低水泥工业产生的CO_2,有关公司采取了降低熟料热耗,使用代用燃料,生产复合、混合水泥以降低熟料掺加量的方法。另外,公司还对水泥熟料的化学成分开展研究,开发与PC熟料化学成分较为接近的低CO_2排放的新品种水泥。     

水泥行业CO2排放特征及治理技术研究

本文系统梳理分析了水泥不同种类和各工序的CO₂排放特征，其中，工艺、燃料直接CO₂排放占比达90%，与物料中碳酸盐的含量正相关，与燃料发热量和利用率负相关，电力间接CO₂排放占比约10%，特种水泥由于减少了碳酸盐分解造成的碳排放，总体碳排放量较低。新型干法水泥生产过程可分为生料制备、熟料煅烧和水泥粉磨三个阶段，工艺和燃料CO₂排放主要发生在熟料煅烧阶段，其尾气中CO₂浓度一般在11%～29%。研究分析了碳替代/碳捕集等控碳技术、CO₂资源化利用技术。水泥厂碳替代主要是原料替代、熟料或水泥替代、燃料替代等，可分别实现减碳10%、25%～50%和30%以上；碳捕集主要有富氧燃烧和烟气CO₂捕集，水泥窑富氧燃烧技术有全氧燃烧和分解炉全氧燃烧技术两种。捕集技术主要采用化学吸收法、固体吸附法；在CO₂综合利用方面，针对水泥厂的特殊应用场景，矿化具有较好的应用效果，如采用混凝土养护技术，制备高附加值的微纳米碳酸钙等。     

O_2/N_2与O_2/CO_2气氛中水泥生料碱金属挥发情况对比研究

O_2/CO_2燃烧技术在水泥行业的应用会导致水泥生料中碱金属的挥发特性发生改变。本文利用LIBS检测技术分析了CO_2浓度对Na、K挥发特性的影响,同时还探究了不同CO_2浓度下温度对Na、K挥发特性的影响。研究结果发现:CO_2气氛会对水泥生料中碱金属的释放有抑制作用,且CO_2气氛对K与Na的影响效果不同。随着温度的增加,两种碱金属的挥发比例也随之升高。CO_2气氛对Na挥发特性的影响随着温度上升而减弱,但其对K挥发特性的影响却随着温度上升而增强。     

水泥窑协同处置固体废物对熟料率值和污染物排放的影响

利用Aspen Plus软件建立水泥工业预分解窑系统的工艺模型,模拟水泥窑协同处置废旧轮胎、城市生活垃圾MSW、肉骨粉MBM、废塑料和甘蔗渣5种替代燃料对熟料率值和污染物排放(主要是CO_2、NO_x和SO_2)的影响。结果表明,在煤中掺加20%的肉骨粉MBM,可以在喂料量增加0.49%的情况下,热耗降低6.4%,CO_2排放量减少4.4%,是较理想的替代燃料。研究还发现,当热量替代率TSR达到30%时,肉骨粉MBM能导致LSF增加1.5%,城市生活垃圾MSW对SM和IM有较大的影响;除甘蔗渣外,都具有CO_2减排作用;城市生活垃圾MSW和肉骨粉MBM会导致NO_x排放增加,其他影响不大;废旧轮胎因含硫量较高,导致SO_2排放增加,其余替代燃料均具有SO_2减排作用。     

中国水泥工业CO_2排放量的定量分析

我国水泥产量占全球60%左右,水泥工业碳排放长期以来被国际社会严重高估,采用LCA方法对我国2011年碳排放进行了定量计算,中国水泥平均CO_2直接排放系数和平均CO_2排放生产系数分别是0.477 8 t/t和0.545 0 t/t,2011年中国的水泥工业直接排放的CO_2和生产排放CO_2量分别是9.983亿t和11.364亿t;而水泥生命周期碳排放量和直接碳排放量分别是8.553亿t和6.386亿t。RMCO_2、FD_(CO_2)、ED_(CO_2)、TD_(CO_2)和CS_(CO_2)的比例为53.8%、28.3%、7.94%、0.86%和-29.64%,与发达国家相比,我国水泥工业碳排放指数较低。     

Emission characteristics of methanol combustion in constant volume spherical vessels

Emission characteristics of methanol combustion were studied by means of constant volume combustion in spherical vessels, the crevice volume of which was minimized as much as possible. CO, unburnt methanol (UBM), formaldehyde and NO_x were important primary emission species from the environmental viewpoint. The yields of these emissions were measured as functions of equivalence ratio ?. CO and NO_x emissions corresponded to calculated equilibrium compositions at the adiabatic flame temperatures. On the other hand, UBM and formaldehyde were not predicted. UBM had a minimum value at ? ≈ 1.1. UBM and formaldehyde emissions were pressure-dependent, indicating that these emissions were related to quenching phenomena. By employing a larger vessel with a smaller surface/ volume ratio, these emissions could be reduced considerably. Methyl nitrite was produced as an important emission species via post-combustion reactions between UBM and NO_x. Water addition was found not to affect the emission characteristics seriously.     

Modification of boiler operating conditions for mercury emissions reductions in coal-fired utility boilers

US EPA's studies have determined that mercury emissions from coal-fired power plants pose significant hazards to public health and must be reduced. Coal-fired power plants represent a significant fraction of the anthropogenic emissions of mercury into the atmosphere. Mercury emissions are impacted by factors such as coal type, boiler operation, fly ash characteristics and type of environmental control equipment installed on the unit. Field data show a wide variation in the fraction of mercury that is emitted in the gaseous phase, as elemental and oxidized mercury vapor, and as particulate-bound mercury. Oxidized mercury is a preferable species because is less volatile at stack temperatures, water-soluble, and tends to interact with mineral matter and char, and cold-end air pollution control devices. There is also evidence that boiler-operating conditions could be used to influence mercury behavior in the boiler, since they affect the thermo-chemical conditions for mercury formation and reduction. However, operation of boiler control settings, which result in mercury removal benefits, should also consider the tradeoff between mercury reduction and other emissions (for example, NO_x and CO), the level of unburned carbon in the fly ash, unit efficiency and the performance of particulate control equipment.This paper reports fieldwork performed to investigate the feasibility of affecting mercury emissions from coal-fired plants by manipulating boiler control settings. Full-scale testing was performed at two units. One of the units is equipped with a back-end train that includes a rotary air preheater followed by two electrostatic precipitators in series. The other unit is equipped with hot and cold precipitators and a tubular air preheater. A strategy for mercury control by selectively manipulating boiler control settings, if used in combination with other control measures such as sorbent injection, should provide a cost-effective option for mercury control.     

Emission of ammonia (NH3), nitrous oxide (N2O) and methane (CH4) from a dairy hardstanding in the UK

Emissions of ammonia (NH₃), nitrous oxide (N₂O) and methane (CH₄) from uncovered yard areas (hardstandings) of a UK dairy farm were measured between October 1997 and August 1999. Measurements were concentrated after morning milking when the yard had been scraped, and at positions accounting for differences in slurry coverage and manure type. Over two seasons, the mean NH₃ emission from a number of season and position categories on the hardstanding were 0.27 g N m⁻² h⁻¹ in winter and spring, 0.45 g N m⁻² h⁻¹ in summer when the feeding/loafing area was not included, increasing to 1.51 g N m⁻² h⁻¹ when this area was included, and 5.0 g N m⁻² h⁻¹ for the feeding/loafing area alone. The feeding/loafing area was close to the slurry lagoon where excreta were continuously deposited and not scraped to the slurry lagoon, as was the rest of the hardstanding. A diurnal study of emissions in the summer showed a marked decrease with time after the yard was scraped following the first milking, with emissions increasing again after evening milking when fresh excreta were deposited. Nitrous oxide emissions were more variable than NH₃, with an order of magnitude difference between lowest and highest emissions measured at the same time. Mean N₂O emission rates were 3.3 μg N m⁻² h⁻¹ in winter and spring, 6.5 μg N m⁻² h⁻¹ in summer when the feeding/loafing area was not included, increasing to 7.8 μg N m⁻² h⁻¹ when this area was included, and 17.9 μg N m⁻² h⁻¹ for the feeding/loafing area alone. Large mean methane emissions were measured, 185 mg C m⁻² h⁻¹ in winter and spring, decreasing to 57.3 mg C m⁻² h⁻¹ in summer when the feeding/loafing area was not included, increasing to 72.9 mg C m⁻² h⁻¹ when this area was included, and 151.2 mg C m⁻² h⁻¹ for the feeding/loafing area alone. Therefore in summer, emissions measured directly from a dung pat [0–5 cm] that had not been scraped from the loafing area were much greater than from scraped hardstanding areas, but in winter there were still significant emissions from the remaining slurry post-scraping. The experimental design was not sufficient to elucidate the physico-chemical variables controlling the measured emissions, but the data were put into context by estimating the annual emission of these pollutant gases from this one dairy farm. These were estimated at 0.43 t NH₃-N y⁻¹, 0.3 kg N₂O-N y⁻¹ and 1.0 kg CH₄-C y⁻¹. Therefore, uncovered farmyard areas that regularly have excreta deposited on them are significant but previously unaccounted for sources of NH₃ loss, less so for N₂O and CH₄, and require further study to assess the significance of these emission sources within the UK and worldwide. This revised version was published online in August 2006 with corrections to the Cover Date.     

乙烯装置低火炬排放开车探讨

针对抚顺石化新建80万t/a乙烯装置首次开车过程,在乙烯产品没有合格之前,大量的物料排放至火炬系统,不仅造成物料的浪费,给企业造成损失;而且大量排放造成环境污染。在装置检修期间,通过和同行业的交流和讨论,装置现场进行了一些技术改造,在2013年11月的装置开车期间,基本实现了低火炬排放的开车,大大降低了物料的排放。     

汽油含硫量对排放的影响研究

随着我国国民生活水平的提高和汽车工业的发展，汽车逐渐的在我国普及开来，本文针对汽油这种汽车燃料的含硫量对排放量的影响进行了一定的实验，并且得出了相关的实验数据和实验结果。     

The analysis of organic matter in coke oven emissions

A detailed analysis of coke oven emissions is reported. Measurements were made on samples collected at various workplace locations on the oven top. A new type of sampling system was used and is described. Results range from volatile monoaromatic compounds including benzene to polycyclic aromatic hydrocarbons (PAH) of six fused rings. Estimates of errors which may arise when sampling for PAH by filtration are given.     

10000t/d水泥线的NOx超低排放应用实践

通过优化设计自脱硝,抬高三次风风管,下移煤粉燃烧器,多层多点布置燃烧器,增大自脱硝还原区,提高自脱硝效率,实现NO_x本底排放低于350 mg/m³。结合SNCR精准脱硝技术,多层多点布置喷枪,精确计量每组喷枪的氨水流量和压缩空气量,动态调节喷枪的雾化效果,控制烟囱NO_x排放(标况下)低于50 mg/m³,吨熟料氨水用量仅有2.0～2.2 kg/t。     

Comparison of PAH and regulated harmful matter emissions from biodiesel blends and paraffinic fuel blends on engine accumulated mileage test

This study investigated polycyclic aromatic hydrocarbon (PAH) and regulated harmful matter (traditional pollutant) emissions, fuel consumption, and the assessment of the inferior condition of engine oil from heavy-duty diesel engines (HDDEs) fueled with palmbiodiesel–PDF (premium diesel fuel) blends and paraffinic–palmbiodiesel blends under brand-new (the mileage was zero) engines accumulated mileage test. Experimental results indicated that the emissions of THC and CO increased with operation time but the emissions of NO_x and PAHs decreased with operation time between 0 and 300 h (18,000 km). Using palmbiodiesel–PDF blends or paraffinic–palmbiodiesel blends instead of PDF in HDDEs reduced the emissions of THC (10.7–44.2%), CO (0.664–15.6%), CO₂ (0.763–2.55%), NO_x (1.25–4.97%), PM (6.11–26.8%), total PAHs (43.0–90.2%) and total BaP_eq (63.1–89.6%) significantly.     

LLDPE装置己烷系统的环境治理改进

兰州石化LLDPE装置的含氮气己烷回收系统由于历史原因无法有效回收,造成周围环境污染较为严重,给邻近各区的动火施工作业造成极大的危害.经过对该系统进行改造治理可以大大减少周边作业环境污染,同时可以节约能源,降低装置物耗.     

Comparative analysis of CO2 and SO2 emissions between combined and conventional cycles with natural gas and fuel oil consumption over the Spanish thermal power plants

The concern over ‘global warming’ and ‘acid rain’, stands out the possibility of re-converting fuel-oil boilers into natural gas, because SO₂ emissions would be almost annulled but also because it would mean a great decreasing of ‘carbon’ in the fuel matrix, reducing also CO₂ emissions. Another important fact is the progressive substitution of conventional power plant schemes for combined cycles, due mainly to their higher efficiency. In this paper, a comparison (in terms of emissions) was carried out between both cycles for natural gas and fuel-oil consumption over a representative Spanish thermal power plant. Finally, a comparison with experimental values has been performed.