氯酸盐复合吸收剂同时脱硫脱硝试验研究

通过一种新型的NaClO/NaClO2复合吸收剂,在小试级别的喷淋塔装置内进行同时脱硫脱硝试验研究.通过考察各种工艺运行参数对脱除效率的影响,确定了NaClO/NaClO2复合吸收液同时脱硫脱硝的工艺条件:NaClO浓度为4mmol/L,NaClO2浓度为2mmol/L,吸收液初始pH值为5.5,液气比为25L/m3,烟气流量为20m3/h,反应温度为50℃.最佳工艺条件下,平均脱硫脱硝率可分别达到99.7%,93.9%.NaClO/NaClO2复合吸收剂成本比单纯使用NaClO2要低,而脱硝效率有较大提高.     

几种改性同时脱硫脱硝吸收剂的比较研究

利用模拟烟气,在固定床上对几种改性同时脱硫脱硝吸收剂的性能进行了比较实验研究。结果表明:EDTA合铁、H2O2、尿素、半胱氨酸合铁、锰系物M以及复合剂F(N/NaClO2)等添加剂改性后其脱硫效率提升并不明显,但脱硝效果差异较大,其中复合添加剂F改性后脱除效率最高,用量最少,成本最低。利用正交试验,确定了复合添加剂F改性后同时脱硫脱硝剂的最佳实验条件为添加剂含量为0.2%,反应温度为60℃,Ca/(S+N)为1.2。     

Study on method and mechanism for simultaneous desulfurization and denitrification of flue gas based on the TiO2 photocatalysis

Based on the TiO₂ photocatalysis mechanism, a new method of simultaneous desulfurization and denitrification from flue gas was proposed. Preparation of TiO₂ photocatalyst, design of photocatalysis reactor and influencing factors for simultaneous removal of SO₂ and NO, and removal mechanism of SO₂ and NO were studied. After the optimal values of concentration of O₂ in flue gas, the relative humidity of flue gas and the irradiation time in the photocatalysis reactor were used, the efficiencies of removal for SO₂ and NO can be achieved above 98% and about 67%, respectively. According to the results of removal products analysis, the removal mechanism of SO₂ and NO based on TiO₂ photocatlysis can be put forward, namely, SO₂ was oxidized to SO₃ partly, the bulk of NO was oxidized to NO₂, and both were removed by resorbing finally.     

一株同步脱氮脱硫菌的分离鉴定及其代谢特征

为改善传统脱氮工艺中需要外加有机碳源从而增加运行费用的缺点,采用平板夹层培养和Hungate厌氧培养技术相结合的方法,从土壤中分离到一株能够同时利用硫化物和硝酸盐的化能自养型兼性厌氧菌3-1F.16S rDNA测序分析表明,该菌与红平红球菌的相似性达99%.菌株3-1F的代谢特征表现为接种后24 h后进入对数生长期,60 h达到生长高峰,此时,硫代硫酸盐和硝酸盐的利用率分别超过94%和75%,代谢产物以单质硫和氮气为主,含少量硫酸盐.目前,具备同步脱硫脱氮功能的红平红球菌尚未见报道,该菌株的获得为研究废水同步脱硫反硝化工艺并通过生物强化方式提高工艺的处理效能提供了微生物资源.     

Feasibility of an innovative integrated process of simultaneous desulfurization and denitrification for high strength wastewater

An anaerobic expanding-bed reactor was adopted to investigate the feasibility of an innovative integrated process of simultaneous desulfurization and denitrification （SDD） for high strength wastewater. In the reactor, heterotrophic bacteria （including sulfate reducing bacterium and denitrifying bacteria） and autotrophic bacteria （ including Thiobacillus denitrificans） cooperated together by incubating and enriching functional bac- teria on different carriers in the anaerobic activated sludge. Synthetic wastewater with high concentrations of sulfate and nitrate was employed. The experimental resuhs showed that the removal efficiency of sulfate and nitrate was above 85% , elemental sulfur was observed while nitrate was absent in effluent. The balance of sulfur, nitrogen and electron was discussed respectively, which indicated that the integrated SDD process could be actualized. These resuhs might provide a guidance to further investigate the key factors affecting the integrated SDD process and to improve the efficiency of desulfurization and denitrification in wastewater treatment.