高放废液煅烧工艺的研究现状

高放废液安全有效的处理与处置是世界各国关注的重要课题。常采用煅烧技术对高放废液进行预处理，达到实现减少高放废物的产生量、降低高放废物处置的风险的目的。本文主要以常见的几种预处理煅烧工艺技术（罐式煅烧法、喷雾煅烧法、流化床煅烧法和回转煅烧法等）为研究对象，分别从煅烧机理、研究现状及优缺点等多个方面进行较系统的分析探讨。     

Phase Transformations of α-Alumina Made from Waste Aluminum via a Precipitation Technique

We report on a recycling project in which α-Al₂O₃ was produced from aluminum cans because no such work has been reported in literature. Heated aluminum cans were mixed with 8.0 M of H₂SO₄ solution to form an Al₂(SO₄)₃ solution. The Al₂(SO₄)₃ salt was contained in a white semi-liquid solution with excess H₂SO₄; some unreacted aluminum pieces were also present. The solution was filtered and mixed with ethanol in a ratio of 2:3, to form a white solid of Al₂(SO₄)₃·18H₂O. The Al₂(SO₄)₃·18H₂O was calcined in an electrical furnace for 3 h at temperatures of 400–1400 °C. The heating and cooling rates were 10 °C/min. XRD was used to investigate the phase changes at different temperatures and XRF was used to determine the elemental composition in the alumina produced. A series of different alumina compositions, made by repeated dehydration and desulfonation of the Al₂(SO₄)₃·18H₂O, is reported. All transitional alumina phases produced at low temperatures were converted to α-Al₂O₃ at high temperatures. The X-ray diffraction results indicated that the α-Al₂O₃ phase was realized when the calcination temperature was at 1200 °C or higher.     

Glass synthesis and particle size control of BaTiO3 by designing different calcinations modes

Different calcinations techniques are adopted to investigate influences of the calcinations modes on the synthesis of BaTiO₃ powders. Two step calcinations (TSC), in which the samples are first heated to a higher temperature (T1) and then cooled quickly down to a low temperature (T2) for staying, can retard the grain growth and accelerates the phase transformation effectively. Using BaO, TiO₂ and B₂O₃ oxides as precursors, the spherical BaTiO₃ powders with a particle size of 15–20 nm can be achieved based on TSC technique. A detailed investigation upon the possible particle growth mechanism of TSC is also carried out in this paper. The optimized T1can accelerate the phase transition rate while the optimized T2 can refrain the particle growth depending upon the transition of the particle growth mechanism.     

回转窑下料管冷却循环系统的技术改进

针对回转窑下料管经常发生开裂和烧损的现象，本文分析了下料管开裂和烧损的原因，提出将原使用的自循环工业水改为软化水和改进冷却循环系统的进出水管。改进后延长了下料管的使用寿命，同时达到了有效利用余热的效果。     

黑龙江煤系高岭土增白试验研究

对黑龙江省鸡西市某矿煤系高岭土进行了增白试验研究,采用酸法处理降低煤系高岭土中杂质含量,煅烧白度得到了明显提高,促进了煤系高岭土的开发利用。     

Zn-Al水滑石及焙烧产物对甲基橙废水的吸附研究

采用共沉淀法合成的Zn-Al水滑石,借助FT-IR和XRD方法对水滑石及其焙烧产物进行表征,以水滑石前体及其焙烧产物进行甲基橙吸附实验,测试其吸附性能,探讨了金属离子比例、吸附平衡时间、温度等对甲基橙吸附性能的影响。实验结果表明:合成的水滑石结晶度好,焙烧后CO23-层被部分破坏,焙烧态水滑石吸附效果明显高于焙烧前。在焙烧温度为500℃、pH值为5、吸附时间为120min、吸附温度为30℃、投加量为0.5g/L、Zn-Al比为2∶1时的水滑石焙烧产物对甲基橙的去除效果最好,甲基橙最大去除率可达92.3%。     

介孔AlPO4分子筛前驱体的原位焙烧

采用热重(TGA)-差热(DTA)、原位X射线衍射(XRD)、原位红外光谱(FT-IR)和扫描电镜(SEM),对介孔AlPO4分子筛前驱体焙烧过程中的多种变化进行实验研究。TGA-DTA和原位FT-IR结果表明,前驱体脱除主要分为两步:模版剂中N—H键首先断裂,然后甲基(CH3)和亚甲基(CH2)被氧化除去;从原位XRD分析结果可以看出,焙烧过程受温度的影响表现为结晶度的变化,当焙烧温度超过650℃时,AlPO4分子筛会转化成磷石英相和无定形相;SEM照片清楚表明,焙烧使无定型的前驱体转化成柱状分子筛。另外升温速率高于10℃.min-1,会造成分子筛颗粒破碎。     

制备工艺参数对轻烧MgO反应活性的影响

轻烧MgO的制备工艺决定其作为混凝土膨胀剂的性能。该文研究了菱镁石的矿物组成和热分解特性,并研究了煅烧温度、保温时间、升温速率以及冷却方式等煅烧工艺参数对轻烧MgO的反应活性以及水化热的影响规律。结果表明：选用适宜粒度的菱镁石可以制备高活性MgO粉体,煅烧温度超过700℃后,随着煅烧温度的升高, MgO化学活性显著降低,当煅烧温度高于700℃时,随着煅烧时间的延长,虽然烧失量逐渐增大,菱镁石分解更加完全,但MgO化学活性随之降低,在相同煅烧温度和保温时间下,升温速率越快MgO活性越高,快速冷却方式制得MgO反应活性较高。     

平板式脱硝催化剂煅烧过程中温度的测量方法

平板式脱硝催化剂煅烧工艺中温度的变化对催化剂产品最终的物理性能和化学性能有着重要的影响,因此很有必要对平板式脱硝催化剂煅烧过程中的温度进行测量研究,结合平板式脱硝催化剂生产工艺的特点,利用炉温跟踪测量系统对平板式脱硝催化剂煅烧过程中的温度开展了测量。     

利用油母页岩生产高标号水泥实验研究

本文以油母页岩为原料,结合抚顺大火房水泥有限公司现有生产工艺条件,改进生料配料系统,研究用油母页岩配制的生料煅烧方法生产出高标号水泥,同时利用粉煤灰为活性掺合料。粉煤灰二次资源得到了利用,即降低了水泥成本,也减少了粉煤灰的污染,又改善了环境,发展了循环经济,实现了可持续发展。