新型燃煤炉具燃烧原煤和洁净型煤时NO_x排放量对比研究

为考察不同燃料在小区域供暖炉具中的NO_x排放特性,分别以原煤和洁净型煤为燃料进行了燃烧试验;结果表明,相比燃用原煤,洁净型煤可以降低NO_x排放33%,实现炉内降氮的目的;单个洁净型煤在层燃炉具燃烧中经历了动力燃烧、过渡燃烧、扩散燃烧、燃尽等4个过程,在燃烧中通过贫氧气氛抑制、还原性气体和焦炭还原等过程降低NO_x,具有自还原NO_x的作用。     

煤基清洁燃料替代民用散烧原煤的研究进展

综述了民用型煤、民用兰炭、民用洁净焦炭3种煤基清洁燃料的燃烧特性和污染物排放的现状,比较了3种清洁燃料代替散烧原煤的优劣势。同时指出用洁净焦炭代替民用散烧原煤是可行的。     

洁净民用型煤燃烧特性及污染物的排放

选择典型晋城无烟煤和榆林半焦为原料,通过热重法研究原料在不同掺混比下的燃烧特性,制得洁净民用型煤并进行性能评价,得到型煤的燃烧特性及污染物排放规律.结果表明:随着半焦添加比例(质量分数)的增加,型煤抗压强度逐渐下降,热稳定性基本没有变化;随着半焦的加入,型煤的残炭率下降,排放出的NO_x降低;半焦型煤NO_x排放比无烟煤型煤NOx排放减少65.6%,但CO排放为无烟煤型煤CO排放的2倍;当半焦含量为60%时,型煤燃烧时间最长.     

改性花生壳基型煤工业分析

以不同粒级的神木低变质粉煤为原料,配入一定量NaOH改性花生壳黏结剂,通过冷压成型制备出一系列型煤,研究了粉煤粒度对型煤工业分析的影响。结果表明,型煤表面密实平滑,由于改性花生壳中纤维素本身的弹性使型煤出模后轻微膨胀,在表面产生细小裂纹。型煤中M_(ad)=2.5%～3%,比原煤(M_(ad)=5.45%)低,V_(daf)≈70%,远远大于原煤(V_(daf)=36.16%),而灰分产率较原煤略高,说明型煤运输成本较原煤低,燃烧性能较好。随着粉煤粒度减小,型煤的灰分与挥发分含量增加,而固定碳含量与发热量均降低。粉煤制备过程中的偏析现象造成细粒煤中矿物质含量高,所得型煤灰分含量高,热值低。细粒煤所得型煤燃烧过程中挥发分析出孔隙和通道小,阻力大,滞留挥发分多。     

型煤“三大要素”浅谈

型煤作为煤炭的深加工产品，在煤资源的充分利用方面，已显示出它独有的可行性与节能性。从早期碳化煤球与目前广泛应用的腐植酸煤棒、煤球的比较来看，碳化煤球制作工艺复杂、成本高，对煤炭利用的热效率低，特别是碳化煤球降低了原煤的固定碳含量，直接影响了其工业价值。而腐植酸煤球，虽然其工业燃烧指标要优于碳化煤球，但在制作过程中，人们由于忽视了制作型煤的“三大要素”，     

典型煤炭燃料在民用解耦炉中的燃烧实验研究

实验对比研究了烟煤块状半焦及烟煤型煤等煤炭燃料在民用解耦炉中燃烧时的污染物排放特性和炊事能力,并基于解耦测试炉对烟煤型煤的特征尺寸进行优化,验证了解耦炉具对不同种类民用煤炭燃料的适应性。结果表明,民用解耦燃煤炉具特有的结构特征和通风方式有利于NOx和CO的同时减排。若在解耦炉中燃烧烟煤洁净型煤,可进一步实现对SO2和颗粒物(PM)的有效控制。型煤尺寸对炉具污染物排放影响显著,尺寸优化后的烟煤洁净型煤在解耦炉中稳定燃烧时NO, SO2, CO和PM的平均排放浓度按基准氧含量9vol%折算后,分别低于190, 300, 380和30 mg/m3,炊事功率可达1.65 kW。     

洁净煤技术与环境

工业污染物排放是中国大气环境污染的主要原因，本文介绍了不同工业行业燃煤量、ＳＯ２、烟尘、粉尘排放量及不同行业的排放差别及特点，对选煤、型煤、动力配煤、循环流化床燃烧、烟气净化等洁净煤技术的经济、环境效益作了初步分析，指出选煤、型煤、动力配煤是发展洁净煤技术的优先领域，烟气净化、循环流化床燃烧是需要大量开发、推广的技术。     

生物质型煤热解半焦的燃烧特性研究

为开拓低阶粉煤资源高效分质利用途径,在前期制备的能满足直立炉热解要求的生物质型煤的基础上,利用同步热分析仪研究了生物质型煤热解半焦的燃烧性能,并与原煤、原煤半焦及型煤的燃烧性能进行了对比,考察了热解温度对半焦燃烧性能的影响规律。由结果可知,生物质型煤热解半焦的燃烧特征温度低于原煤半焦;随热解温度的升高,原煤半焦的燃烧特征温度呈线性增加,而型煤半焦燃烧特征温度的增加幅度较小;在热解温度较高时,型煤半焦的燃尽性能较好;型煤半焦的综合燃烧特性略差于相同热解温度的原煤半焦,但差别很小。热解温度为650℃的型煤半焦具有最好的燃尽性能和综合燃烧特性。     

锅炉型煤粘结剂的选择及试验

采用粘土和煤泥作粘结剂制造锅炉型煤,各物质所占比例分别为煤泥75%,原煤18%,粘土7%;燃烧型煤后,锅炉温度和单位时间的产气量高于燃烧块煤和原煤,且炉渣和飞灰中的含碳量及排放的CO含量明显降低,不但对环境的污染减少,而且煤炭利用率提高。     

工业固硫洁净型煤的开发与试验研究

简要地介绍了煤与环境保护的关系，较系统地阐述固硫洁净型煤的工艺和技术。通过实验室试验和中试2个阶段的大量试验，该固硫洁净型煤技术固硫效果显著能有效控制和降低燃烧煤中的硫对大气的污染。     

开滦、柳江、大同粉煤制备造气、锅炉型煤的研究

研究出一种MJ20、T复合粘结剂,并用于开滦、柳江、大同粉煤制备造气、锅炉型煤的研制工作,取得了小试及扩大试验的成功。型煤具有较好的冷、热强度及防水性。     

湿料低压成型制防水生物质型煤的研究

介绍了运用湿料低压成型工艺制备生物质型煤的工艺流程及研究过程,生产中研发了具有免烘干、防水、固硫三重功效的TX添加剂;阐述了层燃锅炉对煤质的要求、生物质型煤的配制及在锅炉上的运行操作情况;测试结果表明,湿料低压成型技术投资少、生产成本低,所制型煤燃烧效率高、环保效果好。     

Comparative results of the combustion of lignin briquettes and black coal

A new type of biofuel—hydrolytic lignin briquettes—was tested as compared with ordinary SS coal in fuel-bed firing in a Universal-6 boiler. It was found that the (total) efficiency of the boiler with the firing of lignin briquettes was 38% higher than that with the use of black coal. Carbon loss in the combustion of briquettes was 1%, whereas it was 48.2% in the combustion of black coal. The emission of harmful gas pollutants into the environment in the combustion of briquettes was lower than that in the combustion of coal by a factor of 4.5.     

型煤与焦粉型焦粘合剂的研究及应用

探讨了型煤粘合剂的粘结机理 ,介绍了几种主要粘合剂的分类 ,重点论述了WIN -1型民用与锅炉型煤粘合剂、WIN - 2超微粉造气型煤粘合剂及WIN - 3焦粉型焦粘合剂的研究和应用情况 ,利用这些粘合剂生产的锅炉型煤、造气型煤、焦粉型焦等产品均达到了应用要求     

以焦粉为主制备大块型焦

以焦粉为主要原料快速炭化制取大块型焦，制得的型焦块度大、均匀性好、强度高、气孔率适宜。冲天炉熔炼化铁试验结果表明，该型焦可以作为铸造焦炭使用。     

Technology for the Joint Briquetting of Waste Coal and Sawdust

The results of the experimental release of the test batches of fuel briquettes from carbon-containing products (waste coal and wood sawdust) are presented: by-product. The technical characteristics of fuel briquettes from the waste coals of different regions were determined. Data on the combustion of fuel briquettes from the test batches are given. The theoretical aspects of the formation of the structure and properties of fuel briquettes are considered. The practical significance of the production of fuel briquettes from the carboncontaining products as potential energy sources is demonstrated.     

An Experimental Study on Binderless Briquetting of Low‐Rank Coals

The potential of binderless briquetting as a means of transforming low‐rank coals into low moisture high grade solid fuel products has been studied. Using two dried low‐rank coals, binderless briquettes with high mechanical strength have been successfully produced through mechanical compression. An increase in heating value was achieved as a result of moisture reduction in the briquettes compared to as‐received coals. The residue moisture content in the briquettes had a predominant effect on briquetting characteristics and there existed an optimum moisture content for the maximum briquettes strength. The chemical structure and wettability of binderless briquettes were analyzed using FTIR and contact angle measurement. The results showed that hydrophobicity and chemical structure significantly affected the briquette properties.     

Low-cost carbon-based briquettes for the reduction of no emissions from medium–small stationary sources

In this paper, a novel method for preparing low-cost carbon-based briquettes is described. This procedure includes the briquetting of the carbon material, subsequent activation and finally an equilibrium adsorption impregnation of the active phase. A local low-rank coal was used for the preparation of the carbon briquettes, while both a model vanadium compound (V₂O₅) and the ashes of a petroleum coke (PCA) were used as the precursors of the active phase. The catalytic briquettes have been tested for NO reduction. The effect of a HNO₃-oxidation previous to the impregnation has been also evaluated. The reduction tests have been carried out in presence of oxygen and with the addition of ammonia as reducing agent. The briquettes have shown to be active for NO reduction at low temperature (100–300 °C). Surface chemistry as well as the porous structure of the support, affect the catalyst behaviour. In general terms, higher NO reduction efficiencies were measured for the catalysts prepared using the pre-oxidised briquettes.     

Curing temperature effect on mechanical strength of smokeless fuel briquettes prepared with molasses

Environmental acceptable smokeless fuel briquettes have been prepared with a low-rank coal and olive stone as biomass. The binder chosen for this study was molasses which acts with different roles, as chemical and matrix type. The effect of the curing temperature on these briquettes has been studied by Fourier transform infrared spectroscopy, temperature programmed decomposition (TPD) followed on-line by mass spectrometry and optical microscopy. TPD experiments help to predict the final properties of the briquettes more clearly than infrared spectroscopy. The aliphatic structures and methoxy groups as well as the hydrogen bonds decrease during the curing. On the other hand, the carboxylic groups tend to be formed due to the oxidation produced by the effect of curing temperature. In addition, the briquettes cured at 200 °C, 2 h showed the highest mechanical strength. These curing conditions also produce waterproof briquettes due to the presence of carboxylic groups which contribute to the stabilisation of the briquettes because of the formation of hydrogen bonds.     

Clean fuel-magnesia bonded coal briquetting

Benefaction from coal fines as solid fuel in Turkey is very much important for economical development. Beneficiation from washed coal fines in the industry using solid fuel at lump size and in the municipal areas as an household solid fuel may be only provided by hot briquetting of the coal fines. The most practical common way of that benefication from coal fines in our country have been hot binding by sulfite liquor–sulfite liquor-melas and lime mixtures. Harmful the flue content of sulfite liquor-melas may only be eliminated by lime, a type of solid additive. However, cold bonded briquettes produced from coal fines are environmentally free. Just ash contents of these briquettes increase at a certain degree and heat content of them decrease at a certain extent. By using magnesia binder showed in this study, Tunçbilek lignite fines have been briquetted by cold and hot briquetting techniques. The qualities of briquettes produced by cold binders were compared with to those produced by other hot binding methods As a result, magnesia binder showed the similar characteristics with those of the briquettes produced by only cold bonded gypsum. Use of magnesite mixture and gypsum just as only cold binder was not suitable for the requirements from the coal briquettes to be used as solid fuels, particularly from household fuels, but just only as cold additive should be used.