The reuse of municipal solid waste incinerator fly ash slag as a cement substitute

The results of the treatment of fly ash from a municipal solid waste incinerator (MSWI) by melting are described, and the safety and the effectiveness of using the slag produced by this melting treatment are studied. The properties of the MSWI fly ash slag were analyzed, to evaluate the feasibility of its reuse as a substitute for part of the cement required in mortar preparation. This MSWI fly ash slag was found to be comprised mainly of SiO₂ and CaO, which can be substituted for up to 20% of the cement content in mortar, without sacrificing the quality of the resultant concrete. In fact, the concrete thus produced has greater compressive strength, 10% higher than that without the substitution. The setting time of the fresh mortar becomes lengthens as increasing amounts of cement are replaced; while the spread flow value increases with the increasing percentage of cement substitution. X-ray diffraction analysis reveals that when the W/C=0.38 and the curing AGE=28 days, the crystal patterns in the mortar samples, prepared with different amounts of cement having been replaced by MSWI fly ash slag are similar. According to the results of the toxic characteristic leaching procedure analysis, MSWI fly ash slag should be classified as general non-hazardous industrial waste, that meets the effluent standard. Therefore, the reuse of MSWI fly ash slag is feasible, and will not result in pollution due to the leaching of heavy metals.     

袋式除尘器在燃油锅炉上的应用

从设计理念和实践2个方面介绍了袋式除尘器在煤油锅炉上的应用，为其在电力行业的推广应用提供了经验。     

高掺量粉煤灰烧结砖的制备

研究了高掺量粉煤灰烧结砖的制备工艺条件。结果表明：采用半干压成型，在成型压力19．6MPa、煅烧温度1000—1050℃、保温时间8h的条件下，可制得粉煤灰掺量高达80％的烧结砖，其物理力学性能及耐久性能都超过MU15普通粘土砖。     

利用粉煤灰固化风积土的试验研究

采用正交优化试验方法,并通过采用掺加新型固化剂的方法对风积土进行固化试验研究.研究结果表明,影响稳定土无侧限抗压强度大小的主要因素是水泥量,其次是石灰和碎石掺量.粉煤灰掺量为40%、水泥掺量为1 5%、碎石掺量为40%、石灰掺量为8%、固化剂掺量为5%时,无侧限抗压强度最大.在水泥掺量一定的情况下,稳定土的无侧限抗压强度随着固化剂掺量的增大而提高.同时初步探讨了掺加固化剂后粉煤灰类稳定土的固化机理.通过现场工业性试验和观测,结果表明,试验段水泥稳定土基层状况良好,在公路上未发现由于水泥稳定风积土的某种缺陷所引起的变形和开裂,且弯沉值满足有关要求.     

谷氨酸晶体分离工艺研究

采用以浅层理论制作的固液分离器对味精生产中的谷氨酸废液和结晶母液进行分离，可加强对细粒级谷氨酸晶体的回收。其分离直径可达12μm。分离效率优于传统的滑槽工艺。     

煤灰渣利用中对人群所产生辐射影响的评价

煤的开发与利用产生了大量的灰，渣等固体废物，占用大量土地，污染土壤和水源，成为四大公害之一，因而对煤灰，渣的治理和综合利用一直受到人们的关注。然而，由于煤灰渣中的天然放射性水平较高，因此，在煤灰渣的综合利用，尤其在用作建筑材料时，不可避免地要受到其放射性核素的危害。本文在对四川省各燃煤电厂排放灰渣中的^238U,^232Th,^220R,^40X并无然放射性核素进行分析和研究的基础上，用UNSCEAR1982年报告所推荐的计算模式估算了各电厂煤灰渣制度建材对公众所产生的附加辐射剂量，评价了煤灰制度建材对环境和人群所产生的辐射影响，并提出了控制煤灰渣在建材中的最大掺合量，为其它作用的使用煤灰渣提出了科学的理论依据。     

医疗垃圾焚烧飞灰中重金属浸出的影响因素

以四川某城市为例,对医疗垃圾焚烧飞灰进行了重金属的浸出特性实验,探讨了不同液固比、初始pH值及浸取剂对飞灰中重金属Cu、Zn、Pb、Cd、Ni的浸出影响.结果表明,重金属的浸出率随着液固比的增加而增加;重金属在酸性条件下较易浸出,而在碱性条件下渗滤较少;不同的浸取剂对重金属的浸出也有一定影响.     

发动机机油净化装置的研制与应用

车辆发动机每年在换季时都需要更换不同牌号的机油。为了使换下来的机油能够在第二年重复再利用,中原油田分公司采油五厂研制了污油机油净化处理装置。实践证明,净化后的机油完全可以达到使用技术要求。这样既能减少浪费,又能保护环境不受污染,经济效益也十分明显。     

Removal of elemental mercury by iodine-modified rice husk ash sorbents

Iodine-modified calcium-based rice husk ash sorbents(I2/CaO/RHA) were synthesized and characterized by X-ray diffraction,X-ray fluorescence,and N2 isotherm adsorption/desorption.Adsorption experiments of vapor-phase elemental mercury(Hg0) were performed in a laboratory-scale fixed-bed reactor.I2/CaO/RHA performances on Hg0 adsorption were compared with those of modified Ca-based fly ash sorbents(I2/CaO/FA) and modified fly ash sorbents(I2/FA) .Effects of oxidant loading,supports,pore size distribution,iodine impregnation modes,and temperature were investigated as well to understand the mechanism in capturing Hg0.The modified sorbents exhibited reasonable effciency for Hg0 removal under simulated flue gas.The surface area,pore size distribution,and iodine impregnation modes of the sorbents did not produce a strong effect on Hg0 capture effciency,while fair correlation was observed between Hg0 uptake capacity and iodine concentration.Therefore,the content of I2 impregnated on the sorbents was identified as the most important factor influencing the capacity of these sorbents for Hg0 uptake.Increasing temperature in the range of 80-140°C caused a rise in Hg0 removal.A reaction mechanism that may explain the experimental results was presumed based on the characterizations and adsorption study.     

Characterization of mechanochemical treated fly ash from a medical waste incinerator

The mechanochemical treatment of fly ash generated from a medical waste incinerator was subjected to grinding for 2 hr at 400 r/min in a planetary ball mill. The treated fly ash was characterized by a suite of analytical methods including High Resolution Gas Chromatograph/High Resolution Mass Spectrometer, Mastersizer 2000 Particle Size Analyzer, QUADRASORBTM SI Surface Area Analyzer, Scanning Electron Microscopy and X-ray di raction. Results showed that abatement e ciency of polychlorinated dibenzop- dioxins and polychlorinated dibenzofurans (PCDDs/Fs) in terms of total concentration averagely amount to 76% which was relatively higher than that of I-TEQ concentration averagely amount to 56%; the most concentration of toxic congeners as well as isomers of PCDDs/Fs decreased after mechanochemical treatment. The treated fly ash was characterized by a more homogeneous distribution of concaves as well as the significant decreasing in overall particle size and great enlargement in surface area. The major crystallization phases or intensities were considerably changed by mechanochemical treatment, of which a new phase containing chlorine formed may be a possible factor suggesting chlorination reaction occurring on the crystalline surface.