常温下内循环厌氧反应器的启动研究

研究了内循环厌氧反应器(IC反应器)在常温下处理葡萄糖配水的启动特性。结果表明:在运行温度为25~35℃的条件下,反应器经70 d启动完成,且IC反应器具有较好的处理效果,反应器内能形成大量的颗粒污泥。启动完成后,进水COD浓度在3 000 mg/L左右时,COD去除率一直保持在95%以上,出水COD浓度维持在200 mg/L左右。当HRT为5.8 h,容积负荷为11.9 kg/(m3.d)时,出水VFA低于200 mg/L,产气量为33 L/d,反应器运行正常。     

宝钢焦化废水处理技术发展与现状

焦化废水的处理一直是国内外废水处理领域的难题之一。文章以宝钢为例,介绍并分析了该企业焦化废水处理技术的发展与现状。     

冷轧废乳化液破乳技术研究进展

冷轧废乳化液是轧钢过程中排放的高浓度难降解废水,治理的关键是破乳技术。主要介绍了混凝工艺、膜分离工艺、电凝聚气浮工艺、Fenton氧化工艺、微电解工艺、微波破乳工艺原理及研究现状,并对每种工艺在乳化液废水破乳中的优缺点进行了阐述。其中混凝破乳和膜分离破乳是目前应用最广泛的技术,其他技术由于运行管理以及成本的原因应用相对较少,今后破乳技术的发展应该是高效、低成本的新技术开发或者对原有破乳技术进行革新。     

Zn/Fe体系湿法催化氧化高效脱除沼气中H2S的研究

提出了Zn/Fe体系湿法催化氧化脱除沼气中H2S新工艺,阐述了反应机理、实验装置和工艺流程,考察了各单因素操作条件对H2S脱除效率的影响,在此基础上进行的综合条件实验,脱硫效率都维持在99.6%以上,净化后沼气中H2S含量低于国家标准。过程不消耗任何化工原料,不产生二次污染,体系无降解问题。     

氯化蒸馏废酸还原回收锗

以锗烟尘氯化蒸馏后的废盐酸为原料,以废铁为还原剂,使废酸中的有价金属锗以还原态沉淀富集在渣中,强化氧化氯化蒸馏回收四氯化锗,锗的综合回收率达94．10％。同时生产净水剂用液体氯化铁产品。     

我国废钢加工设备发展中的问题及管理建议

我国钢铁工业的快速发展,带动了废钢回收及废钢加工设备产业的发展。介绍了我国废钢加工设备的生产规模及现状,对废钢加工设备制造企业多元化发展现象进行分析,并对废钢加工设备制造企业的规范化管理提出合理化建议。     

鞍山市铁矿景观格局变化的遥感调查

采用1997和2007年2个时相的卫星遥感数据,对鞍山市城区周边铁矿典型景观类型的面积及其10年来的变化进行了遥感调查和分析。结果表明,国有矿山采矿场的面积相对稳定,边界无明显变化,民营矿山采矿场面积增加明显。采矿场面积变化与开采方式有关,国有矿山采用深凹露天开采,对地表破坏较轻,民营矿山采用山坡露天开采,对地表破坏较严重。排岩场的总面积有所增加,个别矿区增加明显。复垦绿地有大幅度增加,但仍低于排岩场扩张的速度。     

Degradation of chlorinated phenols by nanoscale zero-valent iron

Chlorophenols (CPs), as important contaminants in groundwater, are toxic and difficult to biodegrade. Recently nanoscale zero-valent iron received a great deal of attention because of its excellent performance in treating recalcitrant compounds. In this study, nanoscale zero-valent iron particles were prepared using chemical reduction, and the reductive transformations of three kinds of chlorinated phenols (2-CP, 3-CP, and 4-CP) by nanoscale zero-valent iron under different conditions were investigated. The transformation process of the CPs was shown to be dechlorination first, then cleavage of the benzene ring. The removal efficiency of the CPs varied as follows: 2-CP > 3-CP > 4-CP. The reactivity of CPs was associated with their energy of lowest unoccupied molecular orbit (E _LUMO). With the increase in initial concentrations of CPs, removal efficiency decreased a little. But the quantities of CPs reduced increased evidently. Temperature had influence on not only the removal efficiency, but also the transformation pathway. At higher temperatures, dechlorination occurred prior to benzene ring cleavage. At lower temperatures, however, the oxidation product was formed more easily. __________ Translated from China Environmental Science, 2006, 26(6): 698–702 [译自: 中国环境科学]     

钢铁生产行业二英污染特征变化及其排放因子

对我国某省多家钢铁生产企业烧结工序和电炉工序排放烟气中二英（PCDD/Fs）污染水平、排放特征及其排放因子进行了初步研究.结果表明,烧结工序PCDD/Fs毒性当量浓度（以I-TEQ计,下同）为0.003~0.557 ng·m^-3,均值为0.165 ng·m^-3;电炉工序PCDD/Fs毒性当量浓度为0.006~0.057 ng·m^-3,均值为0.025 ng·m^-3.PCDD/Fs毒性当量浓度水平总体较低,较2005~2019年研究报道结果下降1~2个数量级.2005~2020年,钢铁生产行业排放PCDD/Fs毒性当量浓度水平先升高后降低,尤其是新的标准限值实施以及对烟尘等常规污染物进行超低排放控制后,呈现大幅下降.指纹谱图特征显示,所有烟气样品17种PCDD/Fs中最大浓度贡献单体为2,3,7,8-TCDF,与已有研究中以高氯代PCDFs和PCDDs为主不同,且低氯代PCDFs占比有所增加,表明PCDD/Fs生成主要来源有所变化.烧结工序和电炉工序PCDD/Fs同类物指纹分布特征相似,呈现典型的高温热过程特征,两个工序生产过程中PCDD/Fs的生成机制可能均为"从头合成".钢铁生产企业烧结工序PCDD/Fs废气排放因子（以I-TEQ计,下同）为0.003~0.5 μg·t^-1,排放因子平均值为（0.18±0.22）μg·t^-1;电炉工序PCDD/Fs废气排放因子为0.04~0.5 μg·t^-1,排放因子平均值为（0.27±0.23）μg·t^-1;低于UNEP于2013发布的"二英和呋喃排放识别和量化标准工具包"以及2004年我国二英排放清单中的排放因子,建议对我国钢铁生产行业PCDD/Fs排放状况开展调查,更新排放因子.     

Ligand-assisted degradation of carbon tetrachloride by microscale zero-valent iron

Degradation of carbon tetrachloride (CT) by microscale zero-valent iron (ZVI) was investigated in batch systems with or without organic ligands (ethylenediaminetetraacetic acid (EDTA), citric acid, tartaric acid, malic acid and oxalic acid) at pHs from 3.5 to 7.5. The results demonstrated that at 25°C, the dechlorination of CT by microscale ZVI is slow in the absence of organic ligands, with a pseudo-first-order rate constant of 0.0217 h(-1) at pH 3.5 and being further dropped to 0.0052 h(-1) at pH 7.5. However, addition of organic ligands significantly enhanced the rates and the extents of CT removal, as indicated by the rate constant increases of 39, 31, 32, 28 and 18 times in the presence of EDTA, citric acid, tartaric acid, malic acid and oxalic acid, respectively, at pH 3.5 and 25°C. The effect of EDTA was most significant; the dechlorination of CT at an initial concentration of 20 mg l(-1) increased from 16.3% (no ligands) to 89.1% (with EDTA) at the end of 8h reaction. The enhanced CT degradation in the presence of organic ligands was primarily attributed to the elimination of a surface passivation layer of Fe(III) (hydr)oxides on the microscale ZVI through chelating of organic ligands with Fe(III), which maintained the exposure of active sites on ZVI surface to CT.