本文選題：燒結煙氣 + 氧化脫硝　； 參考：《東南大學》2015年碩士論文

【摘要】：氮氧化物(NO_x)是鋼鐵企業(yè)所排放的主要大氣污染物之一,其中鋼鐵燒結工序所產(chǎn)生的NO_x約占整個鋼鐵冶煉主工序的48%左右,是鋼鐵企業(yè)NO_x排放控制的重點。目前全國大部分鋼鐵企業(yè)燒結生產(chǎn)線都配有燒結煙氣脫硫設施,卻沒有配套的脫硝設備,造成的NO_x污染問題日趨嚴重。一方面由于燒結工序所采用的的燃料變化大,燒結礦原料品質參差不齊,造成了燒結煙氣具有溫度低且變化范圍大、NO_x濃度低波動大、含氧量和含濕量大等特點。不適宜直接采用普通燃煤電廠的脫硝方法；另一方面由于燃煤電廠的煙氣脫硝與脫硫是分開進行的,這種傳統(tǒng)的分別脫硫脫硝技術存在設備投資和運行費用高,占地面積大等不足,為此,本文開展了燒結煙氣氧化脫硝的實驗室模擬試驗研究和工程試驗,旨在不影響脫硫效率的前提下,在原有的燒結煙氣脫硫工藝中加入合適的氧化劑,達到NO_x減排的目的。對不同的氧化劑進行分析篩選,選取了NaClO及KMnO_4/NaClO/Ca(OH)_2組合為燒結煙氣氧化脫硝實驗室模擬試驗研究的氧化劑。構建以南京鋼鐵廠2x180m2燒結工序脫硫工藝為原型的旋轉噴霧模擬試驗平臺,進行NaClO/Ca(OH)_2溶液體系和KMnO_4/NaClO/Ca(OH)_2溶液體系的燒結煙氣氧化脫硝實驗室模擬試驗研究,考察了氧化劑溶液pH、模擬煙氣溫度、氧化劑濃度、SO_2濃度及NO濃度這些操作參數(shù)對脫除效率的影響,并對NaClO/Ca(OH)_2溶液體系和KMnO_4/NaClO/Ca(OH)_2組合溶液體系燒結煙氣氧化脫硝的實驗室模擬試驗的過程進行了熱力學計算和試驗機理分析。試驗及分析結果表明,NaClO/Ca(OH)_2溶液體系的實驗室模擬試驗最佳工況為pH=10、Tg=60℃、ms=6mmo/L,在此條件下的平均脫硫脫硝效率分別能夠達到98.8%和60.1%;KMnO_4/NaClO/Ca(OH)_2溶液體系的最佳工況為pH=5.5、模擬煙氣溫度Tg=50℃、KMnO_4/NaClO摩爾比為3(即mp=0.1mmo/L,ms=0.3mmo/L),在此條件下的平均脫硫脫硝效率分別能夠達到98.8%和70.9%。在南京鋼鐵廠2x180m2燒結工序的旋轉噴霧脫硫塔上分別進行了NaClO/Ca(OH)_2溶液體系和KMnO_4/NaClO/Ca(OH)_2溶液體系的燒結煙氣氧化脫硝的工程試驗,試驗結果表明,在氧化劑溶液pH為10、NaClO濃度(ms)為6mmo/L、Ca(OH)_2含固量為30%的條件下,采用NaC10/Ca(OH)_2溶液體系進行工程試驗的平均脫硝率為20%,脫硫率則能達到98%以上：在氧化劑溶液pH為5.5、KMnO_4/NaClO摩爾比為3(即mp=0.1mmo/L,ms=0.3mmo/L)、Ca(OH)_2含固量為30%的條件下,采用KMnO_4/NaClO/Ca(OH)_2溶液體系進行工程試驗的平均脫硫脫硝效率分別能夠達到98%和30%。兩種情況下的原有燒結煙氣脫硫效率均沒有因為加入了氧化劑而受到影響,說明了在燒結煙氣旋轉噴霧脫硫的工藝中加入氧化劑NaClO/Ca(OH)_2或者KMnO_4/NaClO/Ca(OH)_2組合進行燒結煙氣氧化脫硝的方案是可行的,不僅不會影響原有設備的煙氣脫硫效率,還能夠減少氮氧化物(NO_x)的排放,達到脫硫脫硝一體化的目的。
[Abstract]:No _ x (no _ x) is one of the main atmospheric pollutants emitted by iron and steel enterprises, in which the no _ x produced in the sintering process of iron and steel accounts for about 48% of the total main process of iron and steel smelting, which is the key point of Nox emission control in iron and steel enterprises. At present, most iron and steel enterprise sintering production lines are equipped with sintering flue gas desulphurization facilities, but there is no supporting denitrification equipment, resulting in serious NOX pollution problem. On the one hand, because the fuel used in sintering process changes greatly and the raw material quality of sinter is not uniform, the sintering flue gas has the characteristics of low temperature and large range of variation, large fluctuation of NOX concentration, high oxygen content and moisture content, etc. On the other hand, because the flue gas denitrification and desulphurization of coal-fired power plants are carried out separately, the traditional separate desulphurization and denitrification technology has high equipment investment and running cost. Therefore, the laboratory simulation and engineering experiments of oxidizing denitrification of sintered flue gas are carried out in order to add suitable oxidant to the original sintering flue gas desulfurization process without affecting the desulfurization efficiency. To achieve the purpose of reducing NOX emissions. Different oxidants were analyzed and screened, and NaClO and KMnOs 4 / NaClO / Ca (OH) _ 2 were selected as oxidants for the laboratory simulation study of oxidation and denitrification of sintered flue gas. Based on the 2x180m2 sintering process desulfurization process in Nanjing Iron and Steel Plant, a rotating spray simulation test platform was built to simulate the oxidation and denitrification of flue gas in the system of NaClO / Ca (OH) _ 2 solution and KMnO _ (4) / NaClO / Ca (OH) _ 2 solution system. The effects of pH of oxidant solution, simulated flue gas temperature, so _ 2 concentration and no concentration on removal efficiency were investigated. Thermodynamic calculation and experimental mechanism analysis were carried out on the laboratory simulation test of oxidation denitrification of flue gas in NaClO / Ca (OH) _ 2 solution system and KMnO _ (4) / NaClO / Ca (OH) _ 2 composite solution system. The results of experiment and analysis show that the optimum condition of laboratory simulation test for the solution system of NaClO / Ca (OH) 2 is pH 10 ~ (10) TG ~ (60) 鈩，

本文編號：2095316