化工学报
化工學報
화공학보
JOURNAL OF CHEMICAL INDUSY AND ENGINEERING (CHINA)
2015年
8期
3233-3241
,共9页
范镇%陈良勇%刘方%刘坤磊
範鎮%陳良勇%劉方%劉坤磊
범진%진량용%류방%류곤뢰
CO2捕集%钙循环%反应性%模型
CO2捕集%鈣循環%反應性%模型
CO2포집%개순배%반응성%모형
CO2 capture%calcium looping%reactivity%modeling
采用燃料氧燃烧直接供热的氧化钙-二氧化碳双床循环系统已经被研究开发,用于从电厂尾气中脱碳。本研究基于实验和化学反应工程原理建立了分析模型,用于系统地研究循环特征,氧化钙活性衰减,燃料及其炉内热利用率的影响。基于模型推导获得了重要参数:最小循环热损失和最小热需求量,以及对应的固体循环比。它们都受供热燃料灰分和含硫量的影响,也受脱碳率的影响。显然最佳固体循环比介于二者之间。另一个重要参数是燃料在炉内的热利用率。高的热利用率不仅降低燃料需求量,降低其灰分和含硫的影响,降低氧的需求量及其辅助功,而且提高蒸汽循环的发电效率。一个发现是热需求量在临界固体循环比接近无穷大,这就限制了固体循环比的可操作范围,以及燃料的灰分和含硫量。建立的分析模型和推导直接提供了这些变量之间的关系和范围。
採用燃料氧燃燒直接供熱的氧化鈣-二氧化碳雙床循環繫統已經被研究開髮,用于從電廠尾氣中脫碳。本研究基于實驗和化學反應工程原理建立瞭分析模型,用于繫統地研究循環特徵,氧化鈣活性衰減,燃料及其爐內熱利用率的影響。基于模型推導穫得瞭重要參數:最小循環熱損失和最小熱需求量,以及對應的固體循環比。它們都受供熱燃料灰分和含硫量的影響,也受脫碳率的影響。顯然最佳固體循環比介于二者之間。另一箇重要參數是燃料在爐內的熱利用率。高的熱利用率不僅降低燃料需求量,降低其灰分和含硫的影響,降低氧的需求量及其輔助功,而且提高蒸汽循環的髮電效率。一箇髮現是熱需求量在臨界固體循環比接近無窮大,這就限製瞭固體循環比的可操作範圍,以及燃料的灰分和含硫量。建立的分析模型和推導直接提供瞭這些變量之間的關繫和範圍。
채용연료양연소직접공열적양화개-이양화탄쌍상순배계통이경피연구개발,용우종전엄미기중탈탄。본연구기우실험화화학반응공정원리건립료분석모형,용우계통지연구순배특정,양화개활성쇠감,연료급기로내열이용솔적영향。기우모형추도획득료중요삼수:최소순배열손실화최소열수구량,이급대응적고체순배비。타문도수공열연료회분화함류량적영향,야수탈탄솔적영향。현연최가고체순배비개우이자지간。령일개중요삼수시연료재로내적열이용솔。고적열이용솔불부강저연료수구량,강저기회분화함류적영향,강저양적수구량급기보조공,이차제고증기순배적발전효솔。일개발현시열수구량재림계고체순배비접근무궁대,저취한제료고체순배비적가조작범위,이급연료적회분화함류량。건립적분석모형화추도직접제공료저사변량지간적관계화범위。
Post-combustion CO2 removal from flue gas at power plantvia a two-bed CaO-CO2 loop (CaL) with heat provided byin-situ oxy-fuel combustion has been investigated. Based on the principle of chemical reaction engineering, a simple analytical model with one variableN only (solids circulation ratio) has been built and used for analysis of the CaL process systematically, which includes effects from sorbent reactivity, fuel impurity and the utilization of fuel heat to looping. From the model, the minimum heat duty and the looping penalty are obtained. Both of them are impacted by fuel sulfur and ash significantly. The result also indicates that the optimum solids circulation ratioN will be located between the two minimum points. The furnace factor is important, because it can eventually reduce the fuel firing rate, fuel ash and sulfur effect, oxygen requirement and related auxiliary power, and increase steam cycle efficiency. As found, the heat duty approaches to infinite at a critical solids circu-lation ratioNC, which is a constraint to the operableN and the fuel burned. All of the effects are interconnected by the model.