CAJ | 학술논문

对两种典型无烟煤进行了工业分析及热重试验,应用双混合分数（PDF）模型对不同无烟煤掺烧方式下直吹式制粉系统W型火焰锅炉进行了数值模拟,得到了炉内烟气温度场、氧体积分数分布场及烟气速度场.结果表明：两种无烟煤的工业分析参数基本相当,但可磨性和燃烧特性存在明显差异;在炉前掺烧方式下,炉膛温度、氧体积分数分布以及速度场均较对称,但煤粉燃尽率比分磨掺烧方式下明显偏低,炉膛出口烟气温度比分磨掺烧方式下偏高;在分磨掺烧方式下,磨煤机运行模式对燃烧经济性有较大影响;无烟煤与无烟煤也存在混煤掺烧优化的空间,分磨掺烧方式可提高燃烧经济性.
대량충전형무연매진행료공업분석급열중시험,응용쌍혼합분수（PDF）모형대불동무연매참소방식하직취식제분계통W형화염과로진행료수치모의,득도료로내연기온도장、양체적분수분포장급연기속도장.결과표명：량충무연매적공업분석삼수기본상당,단가마성화연소특성존재명현차이;재로전참소방식하,로당온도、양체적분수분포이급속도장균교대칭,단매분연진솔비분마참소방식하명현편저,로당출구연기온도비분마참소방식하편고;재분마참소방식하,마매궤운행모식대연소경제성유교대영향;무연매여무연매야존재혼매참소우화적공간,분마참소방식가제고연소경제성.
Proximate analysis and thermogravimetric tests were carried out to two typical kinds of anthracite,while numerical simulation performed on blended coal combustion with anthracite in a direct-fired pulverizing system for W-shaped flame boilers at different coal blending modes using dual-mixture fraction/PDF approach,during which the in-furnace temperature field,oxygen concentration distribution and velocity field were obtained.Results show that the proximate analysis data for above two kinds of anthracite are basically the same,but their grindability and combustion characteristics are quite different.At the combustion mode of ＂blending before furnace＂,the in-furnace temperature field,oxygen concentration distribution and velocity field are quite symmetrical,but the burn-off degree of coal powder is lower and the furnace outlet temperature is higher than the mode of ＂pulverizing coal in different mills＂.At the combustion mode of ＂pulverizing coal in different mills＂,the operation pattern of coal mill affects the combustion economy greatly,in which case optimization is possible even under the condition that one kind of anthracite is blended with another,therefore the combustion mode of ＂pulverizing coal in different mills＂ is believed to be beneficial for improvement of the combustion economy.