微生物法液相氧化SO2

通过对酸性水溶液、含Fe³⁺水溶液、含Fe²⁺水溶液、细菌菌液和细菌培养基水溶液脱除二氧化硫的实验,探讨了微生物液相氧化二氧化硫的途径.以液相中SO₄^2-浓度考察了Fe³⁺浓度、Fe²⁺浓度、进口SO₂浓度以及温度对脱硫成酸的影响.微生物脱硫有2种机制:一是直接氧化作用,即氧化亚铁硫杆菌(Thiobacillus ferrooxidans)将S(IV)氧化成S(VI);二是间接催化氧化,氧化亚铁硫杆菌在酸性条件下具有快速氧化Fe²⁺成Fe³⁺,增强Fe³⁺对SO₂的液相催化氧化能力,研究表明微生物脱硫以间接催化氧化为主.在浓度0～1.2g/L之间,Fe³⁺和Fe²⁺浓度越高,脱硫效果越好,氧化亚铁硫杆菌表现出对Fe³⁺/Fe²⁺体系氧化SO₂的强化效果.入口SO₂浓度越高,细菌脱硫效率越低,但液相中SO₄^2-浓度随进口SO₂浓度增加变化不大.温度对微生物脱硫影响较大,最佳脱硫温度为30～40℃.     

UV/H2O2光催化氧化法处理表面活性剂废水

采用UV/H2O2光催化氧化法处理含表面活性剂废水,考察了反应时间、体系pH值、表面活性剂初始浓度、H2O2投加量、表面活性剂的种类等因素对处理效果的影响,并初步探讨了表面活性剂降解的反应动力学.结果表明,当初始pH值为4、H2O2投加量为1mL/L,反应时间为20min时,表面活性剂DBS的去除率为96%,AOS的去除率为93%,且UV/H2O2体系中,表面活性剂DBS和AOS的降解反应均符合表观拟一级反应动力学特征.     

磁态厌氧流化床处理印染废水

在厌氧流化床中投加高效脱色菌种;采用聚集—交联固定法,将脱色菌固定于活性污泥上;在反应器内投加磁粉形成稳恒弱磁场,对微生物产生正的磁生物效应来提高生化反应速率,处理人工模拟印染废水。试验结果表明,水力停留时间3h,色度去除率90％以上CODcr去除率44％～49％。与传统生化法相比,该装置投资省,成本低,处理效果良好。启动快,耐冲击负荷,停留时间短,操作管理方便。在实际应用中有广阔的前景。     

乳化液废水均相催化湿式氧化动力学

在2L高压间歇反应釜中,以高浓度难降解乳化废水为处理对象,研究了温度对铜盐均相湿式氧化的影响和动力学特征.结果表明:升高温度对加快后期反应速度更为有利,催化剂有利于中间产物氧化,在200℃催化活性最高,在进水COD48 400mg/L,反应2h去除率为86.6%;催化剂在不同温度作用下机制有所差别:200℃时3个途径反应速度均加快,中间产物加速氧化更明显;220～240℃时反应向生成中间产物方向偏移,活性降低;通用模型能较好地预测均相催化过程.     

化学链燃烧中钙基载氧体CaSO4再生的氧化反应机理

在热重和红外联用进行等温实验的基础上,探讨了氧体积分数为10%、20%,970～1150℃温度范围内化学链燃烧过程中钙基载氧体再生(CaS)的氧化特性.结果显示,CaS氧化的直接产物主要为CaSO4,只有在诱导期生成极少量CaO和SO2;但CaSO4与CaS还可进一步反应,生成更多CaO和SO2.通过对氧气浓度和温度的实验条件改变,研究了CaSO4的转化率、转化速率,并辅以SO2析出速率分析,获得了CaSO4相对于CaO的瞬时选择性、CaSO4的收率和反应选择率.结果表明,钙基载氧体CaSO4再生过程氧化反应的适宜条件为温度970～1000℃以及较高的氧气气氛,这不仅可以抑制SO2的排放量从而得到较高的反应选择率,同时反应过程也具有较高的转化速率.     

脱氮-混凝气浮-UASB-接触氧化法处理垃圾填埋渗滤液

采用脱氮—混凝气浮—UASB—接触氧化工艺处理高氨氮、高浊度的垃圾渗滤液，使处理后出水的各项指标完全达到国家《污水综合排放标准》(GB8978—1996)二级新扩改标准。对废水处理系统的工艺作了简单介绍，并对系统的调试、运行过程进行了技术总结。     

The relationship between oxygen consumption rate and temperature during coal spontaneous combustion

Spontaneous combustion is a major natural disaster in coal production. In the process of exploring coal self-ignition, a series of hypotheses have been put forward, most scholars agree that the current coal-oxygen compound theory. Oxygen consumption rate reflects the status of coal spontaneous combustion, and it is also one of the parameters necessary for numerical simulation of coal spontaneous combustion. In this paper, a coal heating and oxidation experiment was designed, Experimental device consists of heating and oxidation furnace, gas chromatograph, temperature control and data acquisition systems and other equipment components. Three coal samples whose weight each is 5 g were selected for the study. By experiment, oxygen concentration at the inlet and outlet of temperature oxidation furnace was measured. Oxygen consumption rate is calculated in the heating process of coal according to air flow. In the Cartesian coordinate system, the temperature as abscissa and the oxygen consumption rate for the longitudinal coordinates, drawing the relationship between oxygen consumption rate and temperature plot. And then regression analysis was used to analyze the relationship between oxygen consumption rate and coal temperature during the heating and oxidation process of coal. The results show that the oxygen consumption rate and temperature of coal were linear relationships both before and after the critical temperature when the coal temperature is less than 180 °C. Before the critical temperature oxygen consumption rate is low, however it increases rapidly when coal temperature reaches a critical temperature. The result is important for the prevention and treatment of spontaneous combustion of coal.     

疏水型H-ZSM-5分子筛上NO氧化反应的研究

针对NO低温氧化催化剂的抗水汽性差的问题,以疏水型高硅H-ZSM-5分子筛为NO氧化催化剂,在温度为10~90℃、NO进口浓度为0.05%~0.08%,及相对湿度为0~100%条件下,考察了NO的氧化反应.结果表明,H-ZSM-5分子筛的硅铝比由50提高至300时,湿气条件(水汽含量1.18%)下,NO氧化率由20%升高至56%;干气下,低温有利于NO氧化;湿气下(水汽含量1.18%),NO氧化率随着温度的升高先增加后减少,最佳反应温度为20℃,与NOx工业废气的排放温度相近.200h的稳定性试验结果显示,在30℃、NO进口浓度0.08%、空时0.5s、保持相对湿度为50%或100%时,NO氧化率可维持在60%和50%,催化剂具有良好的稳定性.     

非均相催化臭氧处理高浓度制药废水的研究

非均相催化臭氧是一种对高浓度制药废水进行预处理的有效方法.本研究采用单一活性炭吸附、单一臭氧氧化和臭氧/活性炭联用3种体系对实际制药废水进行预处理,并对处理过程中的工艺参数进行优化.结果表明,相比单一活性炭吸附和单一臭氧降解体系,臭氧/活性炭联用体系能显著提高COD、TOC的去除率及BOD5/COD值,并显示出良好的协...     

Oxidation inhibition of sulfite in dual alkali FGD system

A laboratory-scale well-mixed thermostatic reactor with continuously blasting air was used to investigate the oxidation inhibition of sulfite in dual alkali flue gas desulfurization （FGD） system. The effects of operating parameters such as pH value and catalyst concentration on the oxidation were studied. Sodium thiosulfate was used in the system, and was found that it significantly inhabited the sulfite oxidation. In the absence of catalyst, sodium thiosulfate at 12.67 mmol/L had an inhibition efficiency of approximately 98%. While in the presence of catalyst, sodium thiosulfate at 26.72 mmol/L had an inhibition efficiency less than 85.0%. The oxidation reaction order of sulfite in the sodium thiosulfate was determined to be -1.90 and 4）.55 in the absence and presence of the catalyst, respectively. Apparent activation energy of oxidation inhibition was calculated to be 53.9 kJ/mol. Pilot tests showed that the consumption rate of thiosulfate agreed well with the laboratory-scale experimental results.