脱硫灰在干粉砂浆中的应用研究
|
摘要
我国是一个以煤炭为主要能源的国家,电力生产以火力发电为主。S02排放量已居世界首位,其中燃煤排放S02占其总排放量的90%以上。循环流化床燃烧技术是近年来在国际上发展起来的新一代高效、低污染清洁燃烧技术,我国近几年来也有近千台循环流化床锅炉投入运行或正在制造当中。随着电厂循环硫化床脱硫工艺的广泛应用,电厂的脱硫粉煤灰渣量有不断增大的趋势。因此,开展脱硫灰渣无害化、减量化、资源化处理研究迫在眉睫。
本文首先对脱硫灰的化学成分、物理特性、微观结构和活性特点进行了分析,然后利用正交试验探索了生石灰掺入对脱硫灰水泥干粉砂浆的影响；确定了以脱硫灰为主要原料,加入适量水泥,掺入适量激发剂、硅藻土和减水剂,制备干粉砂浆的正交优化试验方案；在正交优化试验方案中,研究了水泥用量、水胶比、硅藻土掺量对脱硫灰水泥干粉砂浆的稠度和7d、28d、60d抗压强度的影响,得出了最佳实验室技术方案。在此基础上,利用X射线衍射和扫描电镜SEM技术进行了脱硫灰的水化机理分析。得出以下结论：
(1)脱硫灰中结晶矿物主要有石英和硬石膏等,结构中存在大量碳质微粒和絮状玻璃态物质,颗粒表面结构比较疏松,且含有大量微小空隙,这是导致脱硫灰需水量大、对减水剂吸附性大的主要原因。同时,正是由于该脱硫灰中存在大量玻璃质物质,使该灰具有较大的火山灰活性。
(2)探索性试验表明,在干粉砂浆中加入一定量的生石灰会造成砂浆早期开裂,主要原因是脱硫灰中含有一定量的游离CaO和Ⅱ-CaSO4,加入生石灰导致砂浆开裂更为严重。
(3)正交试验表明,以脱硫灰为主要原料,加入适量的水泥,掺入少量的激发剂和减水剂,可以制备性能优异的干粉砂浆；最佳方案为A3B2C1,即水泥用量为25%,水胶比为0.80,激发剂掺量为2%；其制品的稠度56mm,28d抗压强度12.94MPa,可以达到M10等级的砌筑和抹面砂浆的要求。
(4)正交优化试验表明,最佳方案为A3B2C1,即水泥用量为20%,水胶比为0.80,硅藻土掺量为3%；其制品的稠度41mm,28d抗压强度10.70MPa,可以达到M10等级的砌筑、抹面和地面砂浆的要求。
(5)微观分析表明,脱硫灰水泥砂浆中晶体矿物主要有石英、方解石、水化硅酸钙等；随着水泥用量的增加,砂浆试块中水化硅酸钙的含量逐渐增多,水化硅酸钙纤维结构越来越密实,强度越高。
Our country is one take the coal as the primary energy country, the electric power production is mainly based on the thermal electric generation. The SO2 emissions have occupied first place in the world, burning coals discharging SO2 accounts for more than 90 percent of its total emissions. Circulating fluidized bed combustion technology is the new generation of highly effective, low pollution clean combustion technology is fairly recent development in the international arenas. Our country also has nearly thousand circulating fluidized bed boilers are in operation or producing in recent years. With wide application in power plant circulating fluidized bed desulphurization process, desulphurization fly ash and slag in power station has a tendency to increase. Therefore, it's imminent to develop treatment researching harmless, reduction, reclamation of desulphurization fly ash and slag. This article first analysed the desulphurization ash's chemical components, physical properties, microstructure and relevant activity, then by the orthogonal experiment, explored the influences of adding the quicklime on the desulphurization ash cement dry-mixed mortar, and determined the orthogonal optimization experiment plan to prepare the dry-mixed mortar by mixing the right amount of cement, activator, diatomite and water reducing agent, regarding the desulphurization ash as the main materials. In the orthogonal optimization experiment plan, the effect of the cement content, the water to binder ratio, the diatomite quantity on the consistency of desulphurization ash dry-mixed mortar and the compressive strength for 7d,28d, the 60d were studied, and then the best laboratory technical schemes were obtained. On this basis, applying the X-ray diffraction and the scanning electron microscope was analysed with the hydrated mechanism of desulphurization ash. This text drew the following conclusions:
(1) Crystalline minerals in desulphurization ash mainly contain quartz and anhydrite,etc. In its structure there are a large number of carbonaceous particulates and flocculent glassy state substances. The surface structure is quite fluffy, and it contains thousands of small gaps. This is the leading cause of water demand in the desulphurization ash and having a high affinity for the water reducing agent. At the same time, because a great deal of glassy material exist in this desulphurization ash, to make this ash have a rather high activity of volcanic ash.
(2) The exploring experiment indicated when a certain amount of quicklime was mixed into mortar, it would cause the mortar early age cracking. The major cause is in the desulphurization ash includes the right free CaO andⅡ-CaSO4, it adds the quicklime that will lead to the mortar cracking more serious.
(3) The orthogonal experiment proclaimed that regarding the desulphurization ash as the main material, mixing the right amount of cement, activator and water reducing agent could prepare the outstanding performance of dry-mixed mortar. The best scheme is A3B2C1, that is to say cement consumption is 25%, the water to binder ratio is 0.80 and the activator quantity is 2%. Its product consistency is 56mm, the compressive strength for 28d is 12.94MPa which can achieve the claim of M10 grade bricklaying and plastering mortar.
(4) The orthogonal optimization experiment indicated that the best scheme is A3B2C1, that is to say cement consumption is 20%, the water to binder ratio is 0.80 and the diatomite quantity is 3%. Its product consistency is 41mm, the compressive strength for 28d is 10.70MPa which can achieve the claim of M10 grade bricklaying, plastering and ground mortar.
(5) Microscopic analysis showed that crystalline minerals in desulphurization ash cement mortar mainly contain quartz, calcite, hydrated calcium silicate and so on. With an increase of cement consumption, the content of hydrated calcium silicate in mortar sample multiplies gradually, the fiber structure of hydrated calcium silicate is getting more and more densely, and the intension is higher and higher.
本文首先对脱硫灰的化学成分、物理特性、微观结构和活性特点进行了分析,然后利用正交试验探索了生石灰掺入对脱硫灰水泥干粉砂浆的影响；确定了以脱硫灰为主要原料,加入适量水泥,掺入适量激发剂、硅藻土和减水剂,制备干粉砂浆的正交优化试验方案；在正交优化试验方案中,研究了水泥用量、水胶比、硅藻土掺量对脱硫灰水泥干粉砂浆的稠度和7d、28d、60d抗压强度的影响,得出了最佳实验室技术方案。在此基础上,利用X射线衍射和扫描电镜SEM技术进行了脱硫灰的水化机理分析。得出以下结论：
(1)脱硫灰中结晶矿物主要有石英和硬石膏等,结构中存在大量碳质微粒和絮状玻璃态物质,颗粒表面结构比较疏松,且含有大量微小空隙,这是导致脱硫灰需水量大、对减水剂吸附性大的主要原因。同时,正是由于该脱硫灰中存在大量玻璃质物质,使该灰具有较大的火山灰活性。
(2)探索性试验表明,在干粉砂浆中加入一定量的生石灰会造成砂浆早期开裂,主要原因是脱硫灰中含有一定量的游离CaO和Ⅱ-CaSO4,加入生石灰导致砂浆开裂更为严重。
(3)正交试验表明,以脱硫灰为主要原料,加入适量的水泥,掺入少量的激发剂和减水剂,可以制备性能优异的干粉砂浆；最佳方案为A3B2C1,即水泥用量为25%,水胶比为0.80,激发剂掺量为2%；其制品的稠度56mm,28d抗压强度12.94MPa,可以达到M10等级的砌筑和抹面砂浆的要求。
(4)正交优化试验表明,最佳方案为A3B2C1,即水泥用量为20%,水胶比为0.80,硅藻土掺量为3%；其制品的稠度41mm,28d抗压强度10.70MPa,可以达到M10等级的砌筑、抹面和地面砂浆的要求。
(5)微观分析表明,脱硫灰水泥砂浆中晶体矿物主要有石英、方解石、水化硅酸钙等；随着水泥用量的增加,砂浆试块中水化硅酸钙的含量逐渐增多,水化硅酸钙纤维结构越来越密实,强度越高。
Our country is one take the coal as the primary energy country, the electric power production is mainly based on the thermal electric generation. The SO2 emissions have occupied first place in the world, burning coals discharging SO2 accounts for more than 90 percent of its total emissions. Circulating fluidized bed combustion technology is the new generation of highly effective, low pollution clean combustion technology is fairly recent development in the international arenas. Our country also has nearly thousand circulating fluidized bed boilers are in operation or producing in recent years. With wide application in power plant circulating fluidized bed desulphurization process, desulphurization fly ash and slag in power station has a tendency to increase. Therefore, it's imminent to develop treatment researching harmless, reduction, reclamation of desulphurization fly ash and slag. This article first analysed the desulphurization ash's chemical components, physical properties, microstructure and relevant activity, then by the orthogonal experiment, explored the influences of adding the quicklime on the desulphurization ash cement dry-mixed mortar, and determined the orthogonal optimization experiment plan to prepare the dry-mixed mortar by mixing the right amount of cement, activator, diatomite and water reducing agent, regarding the desulphurization ash as the main materials. In the orthogonal optimization experiment plan, the effect of the cement content, the water to binder ratio, the diatomite quantity on the consistency of desulphurization ash dry-mixed mortar and the compressive strength for 7d,28d, the 60d were studied, and then the best laboratory technical schemes were obtained. On this basis, applying the X-ray diffraction and the scanning electron microscope was analysed with the hydrated mechanism of desulphurization ash. This text drew the following conclusions:
(1) Crystalline minerals in desulphurization ash mainly contain quartz and anhydrite,etc. In its structure there are a large number of carbonaceous particulates and flocculent glassy state substances. The surface structure is quite fluffy, and it contains thousands of small gaps. This is the leading cause of water demand in the desulphurization ash and having a high affinity for the water reducing agent. At the same time, because a great deal of glassy material exist in this desulphurization ash, to make this ash have a rather high activity of volcanic ash.
(2) The exploring experiment indicated when a certain amount of quicklime was mixed into mortar, it would cause the mortar early age cracking. The major cause is in the desulphurization ash includes the right free CaO andⅡ-CaSO4, it adds the quicklime that will lead to the mortar cracking more serious.
(3) The orthogonal experiment proclaimed that regarding the desulphurization ash as the main material, mixing the right amount of cement, activator and water reducing agent could prepare the outstanding performance of dry-mixed mortar. The best scheme is A3B2C1, that is to say cement consumption is 25%, the water to binder ratio is 0.80 and the activator quantity is 2%. Its product consistency is 56mm, the compressive strength for 28d is 12.94MPa which can achieve the claim of M10 grade bricklaying and plastering mortar.
(4) The orthogonal optimization experiment indicated that the best scheme is A3B2C1, that is to say cement consumption is 20%, the water to binder ratio is 0.80 and the diatomite quantity is 3%. Its product consistency is 41mm, the compressive strength for 28d is 10.70MPa which can achieve the claim of M10 grade bricklaying, plastering and ground mortar.
(5) Microscopic analysis showed that crystalline minerals in desulphurization ash cement mortar mainly contain quartz, calcite, hydrated calcium silicate and so on. With an increase of cement consumption, the content of hydrated calcium silicate in mortar sample multiplies gradually, the fiber structure of hydrated calcium silicate is getting more and more densely, and the intension is higher and higher.
引文
[1]张海燕,许星.国外烟气脱硫技术的发展与我国的现状.有色金属设计,2003,30(1)：38-42.
[2]杨娟,固硫灰渣特性及其作水泥掺合料研究,重庆大学硕士学位论文2006.10
[3]包正宇,不同类型脱硫渣的主要特性及资源化利用研究,武汉理工大学硕士学位论文.2006.4
[4]王福元,吴正严,粉煤灰利用手册.北京：中国电力出版社,1999.
[5]粉煤灰综合利用网.http://www.flyingash.com/
[6]刘卫东,上海市燃煤电厂脱硫废渣综合利用的可行性研究,[粉煤灰]2008.2
[7]刘豪,燃煤固硫及灰渣利用过程中多相反应机理研究,华中科技大学博士学位论文
[8]莫健瑶.干混砂浆浅探[J].广东建材,2005(2)：15-17.
[9]王小艳,干混砂浆的研制及性能研究,河海大学硕士学位论文.2006.6
[10]王能关.干粉砂浆技术发展与展望[]z.房材与应用,2001(10)：42-44.
[11]苑金生,发展干混砂浆的优越性及相关政策,建材发展导向2005年第2期
[12]冉健桩,浅析干混砂浆的优越性,工程建设与管理
[13]黄翠华,干混砂浆外加剂,化学建材2006年第22卷第5期
[14]薛鹏万,韩建军.商品干粉砂浆的研究与开发[J].建材技术与应用,2003,(4)：12-13.
[15]刘啸武,羚炳基甲基纤维素生产技术和发展前景[J].江汉石油职工大学学报,2004(11);58-60
[16]张杰,可再分散乳胶粉在自流平地坪材料中的应用[J].新型建筑材料,2003(6)：28-30.
[17]aJkobWoflibsegr,张量·新型粉末憎水添加剂的性能及其在于拌砂浆中的应用[J].新型建筑材料,2004(6)：36-39
[18]秦鸿根,王元纲等.掺钢渣微粉干粉砂浆的性能与应用研究[J],新型建筑材料,2004(2)：7-9
[19]刘德春、卢忠远,低等级粉煤灰的粒径对干粉砂浆性能的影响[J].新型建筑材料2004(11)：56－58
[20]金骏.矿渣最佳细度和掺量的研究[J].新型建筑材料,2004(11)：58-59.
[21]蔡雪军、李君震,利用钢渣和粉煤灰生产砂浆干粉料闭新型建筑材料 2004(10)12-13.
[22]李相国等.粉煤灰系列干粉砂浆粉的试验研究[J].新型建筑料.2002(n)：29-31.
[23]李先友,干混特细砂瓷砖粘结砂浆研究,重庆大学工程硕士学位论文
[24]焦红娟,金剑,史小兴,三叶型改性聚丙烯纤维在干混砂浆中的性能研究,新型建筑材料2008.2
[25]王培铭、张国防,中国干混砂浆的应用研究概况,[硅酸盐通报]2007.2
[26]路国忠、郑云生、李延军、盛满计,脱硫建筑石膏胶凝材料性能研究及在干混砂浆中的应用,中国重要会议论文全文数据库,2008
[27]]付晓茹,CFB锅炉混烧高硫石油焦脱硫灰渣综合利用研究,河北理工学院硕士学位论文2002.12
[28]王智.流化床燃煤固硫渣特性及其建材资源化研究[D].重庆：重庆大学,2002：25-40.
[29]国家建筑材料工业局.GB5947-86[S].北京：中国标准出版社,1995.
[30]刘文永、付海明、冯春喜、王新刚,高掺量粉煤灰固结材料172
[31]宋远明,流化床燃煤固硫灰渣水化研究,重庆大学硕士学位论文.2007.10
[2]杨娟,固硫灰渣特性及其作水泥掺合料研究,重庆大学硕士学位论文2006.10
[3]包正宇,不同类型脱硫渣的主要特性及资源化利用研究,武汉理工大学硕士学位论文.2006.4
[4]王福元,吴正严,粉煤灰利用手册.北京：中国电力出版社,1999.
[5]粉煤灰综合利用网.http://www.flyingash.com/
[6]刘卫东,上海市燃煤电厂脱硫废渣综合利用的可行性研究,[粉煤灰]2008.2
[7]刘豪,燃煤固硫及灰渣利用过程中多相反应机理研究,华中科技大学博士学位论文
[8]莫健瑶.干混砂浆浅探[J].广东建材,2005(2)：15-17.
[9]王小艳,干混砂浆的研制及性能研究,河海大学硕士学位论文.2006.6
[10]王能关.干粉砂浆技术发展与展望[]z.房材与应用,2001(10)：42-44.
[11]苑金生,发展干混砂浆的优越性及相关政策,建材发展导向2005年第2期
[12]冉健桩,浅析干混砂浆的优越性,工程建设与管理
[13]黄翠华,干混砂浆外加剂,化学建材2006年第22卷第5期
[14]薛鹏万,韩建军.商品干粉砂浆的研究与开发[J].建材技术与应用,2003,(4)：12-13.
[15]刘啸武,羚炳基甲基纤维素生产技术和发展前景[J].江汉石油职工大学学报,2004(11);58-60
[16]张杰,可再分散乳胶粉在自流平地坪材料中的应用[J].新型建筑材料,2003(6)：28-30.
[17]aJkobWoflibsegr,张量·新型粉末憎水添加剂的性能及其在于拌砂浆中的应用[J].新型建筑材料,2004(6)：36-39
[18]秦鸿根,王元纲等.掺钢渣微粉干粉砂浆的性能与应用研究[J],新型建筑材料,2004(2)：7-9
[19]刘德春、卢忠远,低等级粉煤灰的粒径对干粉砂浆性能的影响[J].新型建筑材料2004(11)：56－58
[20]金骏.矿渣最佳细度和掺量的研究[J].新型建筑材料,2004(11)：58-59.
[21]蔡雪军、李君震,利用钢渣和粉煤灰生产砂浆干粉料闭新型建筑材料 2004(10)12-13.
[22]李相国等.粉煤灰系列干粉砂浆粉的试验研究[J].新型建筑料.2002(n)：29-31.
[23]李先友,干混特细砂瓷砖粘结砂浆研究,重庆大学工程硕士学位论文
[24]焦红娟,金剑,史小兴,三叶型改性聚丙烯纤维在干混砂浆中的性能研究,新型建筑材料2008.2
[25]王培铭、张国防,中国干混砂浆的应用研究概况,[硅酸盐通报]2007.2
[26]路国忠、郑云生、李延军、盛满计,脱硫建筑石膏胶凝材料性能研究及在干混砂浆中的应用,中国重要会议论文全文数据库,2008
[27]]付晓茹,CFB锅炉混烧高硫石油焦脱硫灰渣综合利用研究,河北理工学院硕士学位论文2002.12
[28]王智.流化床燃煤固硫渣特性及其建材资源化研究[D].重庆：重庆大学,2002：25-40.
[29]国家建筑材料工业局.GB5947-86[S].北京：中国标准出版社,1995.
[30]刘文永、付海明、冯春喜、王新刚,高掺量粉煤灰固结材料172
[31]宋远明,流化床燃煤固硫灰渣水化研究,重庆大学硕士学位论文.2007.10