玉米秸秆添加比例对污泥堆肥中Cu和Zn形态的影响

采用BCR连续提取法研究了玉米秸秆添加比例对污泥堆肥中Cu和Zn形态的影响.结果表明:重金属不同形态分配比例的变化能够准确反映重金属形态之间的转化规律;堆肥处理重金属总量不会变化,只是不稳定形态之间相互转化,Cu和Zn被大幅"浓缩",玉米秸秆比例越大,"浓缩效应"越明显;玉米秸秆比例增加有助于酸溶态Cu向可氧化态转化,...     

我国中小型锅炉的NOx排放特征与管理对策

对我国中小型燃煤、燃油、燃气锅炉的NOx排放监测数据进行了统计分析,探讨了NOx的排放特征与管理控制现状.研究结果表明:燃煤锅炉中NOx排放质量浓度小于等于400.00 mg/m3的锅炉占76％,NOx平均排放质量浓度为324.60 mg/m3;燃油锅炉中NOx排放质量浓度小于等于400.00 mg/m3的锅炉占84％...     

活性炭纤维低温脱除模拟烟气中的VOC

采用H2O2浸渍的修饰方法对ACF进行化学改性,并利用氮吸附等温线和XPS（X-ray photoelectron spectroscopy）的方法对ACF样品进行表征。通过在反应床上开展吸附实验,由此测定改性前后ACF脱除VOC（甲苯作为VOC的代表物）的效果,同时考察氧气、温度、水蒸气等因素对ACF脱除甲苯的影响。研究发现,改性使得ACF样品比表面积和孔容略有降低,但表面含氧官能团含量增加,吸附甲苯的能力也因此增强。当模拟烟气中O2浓度为5%时,ACF脱除VOC效果达到最佳,超过5%之后,氧的促进效果不再明显;温度40℃为最佳吸附温度;当烟气中加入水蒸气时,ACF对VOC的脱除效率降低。     

The status of flood wastes treatment and future tasks in South Korea

Natural disasters such as typhoon, flood, and heavy rainfall cause damage in South Korea every year during the summer season. After each rainy season, South Korea suffers not only from flood wastes but also from debris that pile up at dams and stagnate at the estuary of the river. Thus, it is very important to handle these types of wastes as quickly as possible to recover from flood damages and to prevent environmental contamination such as offensive odor and water contamination by the leachate from flood wastes. Other countries such as Japan or USA have established and implemented regulations and guidelines for flood waste. Note, however, that South Korea did not establish practical guidelines; hence, the urgency of establishing practical measures for flood waste. In this study, we suggested various ways of making environmentally sound guidelines including the method of reducing the amount of flood waste by environmentally sound treatment process for flood waste, and the method of setting up and operating the temporary storage site for purposes of efficient separation and treatment of flood waste.     

Preliminary environmental impact assessment of PFOS waste treatment in a lab-scale batch subcritical water decomposition operation

Life cycle assessment (LCA) was carried out by SimaPro 7.3 to study the environmental impact of a lab-scale batch subcritical water decomposition operation for a kilogram of Perfluorooctane sulfonic acid (PFOS) waste treatment in this study, a proven process for the decomposition of PFOS pollutants with high concentration. This LCA focuses on not only the main environmental factors from emissions of toxic pollutants, but also the influence from technical characteristics of the iron-induced subcritical water technology including energy and substances consumption during the subcritical water decomposition treatment process. The IMPACT 2002+ environmental model was used to evaluate the 15 midpoint and 4 end-point environmental damages. It was found that the energy consumption to sustain the high temperature (350 °C) and high pressure (23 MPa) in the subcritical water process contributes 99.8 % of the damages. The total negative impact of the SCWD process for 1 kg of PFOS waste treatment to human health, ecological quality, climate change and resources amounts to 1.11 × 10^?3, 8.43 × 10^?5, 9.76 × 10^?4, 9.05 × 10^?4 Pt, respectively. And the improvement of energy efficiency and catalytic effectiveness are two important factors to reduce the environmental impact from the SCWD process for the treatment of PFOS waste.     

Source Identification and Trends in Concentrations of Gaseous and Fine Particulate Principal Species in Seoul,South Korea

Abstract

Ambient measurements were made using two sets of annular denuder system during the four seasons (April 2001 to February 2002) and were then compared with the results during the period of 1996–1997 to estimate the trends and seasonal variations in concentrations of gaseous and fine particulate matter (PM_2.5) principal species. Annual averages of gaseous HNO₃ and NH₃ increased by 11% and 6%, respectively, compared with those of the previous study, whereas HONO and SO₂ decreased by 11% and 136%, respectively. The PM_2.5 concentration decreased by ～17%, 35% for SO₄ ^2?, and 29% for NH₄ ⁺, whereas NO₃ ^? increased by 21%. Organic carbon (OC) and elemental carbon (EC) were 12.8 and 5.98 μg/m^-3, accounting for ～26 and 12% of PM_2.5 concentration, respectively. The species studied accounted for 84% of PM_2.5 concentration, ranging from 76% in winter to 97% in summer.

Potential source contribution function (PSCF) analysis was used to identify possible source areas affecting air pollution levels at a receptor site in Seoul. High possible source areas in concentrations of PM_2.5, NO₃ ^?, SO₄ ^2?, NH₄ ⁺, and K⁺ were coastal cities of Liaoning province (possibly emissions from oil-fired boilers on ocean liners and fishing vessels and industrial emissions), inland areas of Heibei/Shandong provinces (the highest density areas of agricultural production and population) in China, and typical port cities (Mokpo, Yeosu, and Busan) of South Korea. In the PSCF map for OC, high possible source areas were also coastal cities of Liaoning province and inland areas of Heibei/Shandong provinces in China. In contrast, high possible source areas of EC were highlighted in the south of the Yellow Sea, indicating possible emissions from oil-fired boilers on large ships between South Korea and Southeast Asia. In summary, the PSCF results may suggest that air pollution levels in Seoul are affected considerably by long-range transport from external areas, such as the coastal zone in China and other cities in South Korea, as well as Seoul itself.     

Airborne bacterial reduction by spraying slightly acidic electrolyzed water in a laying-hen house

Spraying slightly acidic electrolyzed water (SAEW) has been considered as a potential approach to reduce airborne bacteria in laying-hen houses. In this study, the effects of spraying SAEW on airborne bacterial reduction were investigated in a laying-hen house as compared with using diluted didecyl dimethyl ammonium bromide (DDAB). Averaged air temperature reduced by approximate 1 °C and average relative humidity increased by 3% at a stable ventilation rate (about 2.5 m³ hr^?1 per bird) in the laying-hen house 30 min after spraying (120 mL m^?2). Compared with the control without spraying, the airborne bacterial concentration was reduced by about 0.70 and 0.37 log₁₀ colony-forming units (CFU) m^?3 in the 4 hr after spraying 120 mL m^?2 SAEW (available chlorine concentration [ACC] of 156 mg L^?1) and diluted DDAB (active compound concentration of 167 mg L^?1), respectively. Compared with spraying diluted DDAB, spraying SAEW was determined to be more effective for reducing airborne bacterial in laying-hen houses. The effects of spraying SAEW and diluted DDAB on airborne bacterial reduction in the laying-hen house increased with the increasing available chlorine concentrations for SAEW (156, 206, 262 mg L^?1) and increasing active compound concentrations for diluted DDAB (167, 333, 500 mg L^?1), respectively. Spraying SAEW and diluted DDAB with two levels of spraying volumes (120 and 90 mL m^?2) both showed significant differences on airborne bacterial reduction in the laying-hen house (P < 0.05).

Implications: It is difficult to effectively reduce airborne bacteria in laying-hen houses. This work describes the application of spraying slightly acidic electrolyzed water as a new approach for reducing airborne bacteria in a laying-hen house. The effects of active compound concentrations and spray volumes on the airborne bacterial reductions by spraying SAEW were also investigated. This study provided a new effective and environmentally friendly approach to reduce the airborne bacteria in poultry houses, contributing to bird housing environment management and improving bird health.     

核桃果皮炭粉对3种重金属离子吸附的影响

采用均匀设计的实验方法,研究了2种核桃果皮炭粉(提取水溶性混合物和未提取水溶性混合物的核桃皮炭粉)对Cr、Cu和Cd等重金属离子的吸附最优条件以及对3种离子吸附的影响因素。结果表明,核桃皮炭粉对Cr(Ⅵ)、Cd2+和Cu2+的吸附最优条件为:pH=4,温度为60℃,浓度为150μg/mL,吸附剂用量为2.4 g,时间为120 min;pH=4.5,温度为30℃,浓度为180μg/mL,吸附剂用量为5.4 g,时间为60 min;pH=5,温度为80℃,浓度为210μg/mL,吸附剂用量为0.4 g,时间为100 min;pH和Cr(Ⅵ)浓度增大,不利于2种吸附剂对Cr(Ⅵ)的吸附;pH和温度增大,不利于2种吸附剂对Cu2+的吸附;温度和吸附剂用量增加,有利于2种吸附剂对Cd2+的吸附。未提取水溶性混合物比提取水溶性混合物的核桃果皮炭粉对3种金属的吸附显著。2种吸附剂的吸附率均表现为Cr>Cd>Cu。     

电解-CPAM联用对印染污泥脱水性能的影响

采用铜-石墨为电极,考察了电解电压、反应时间、极板间距和阳离子型聚丙烯酰胺(CPAM)等因素对印染污泥脱水效果的影响。结果表明,在极板间距为3 cm,电压为15 V,反应时间为40 min时,印染污泥的絮体破解效果最佳。该条件下,添加6.67 mg/g(以污泥干基计,DS)CPAM后,印染污泥的比阻(SRF)、毛细吸水时间(CST)与粘度分别下降了59.30%、41.62%和68.14%,滤饼含水率由89.30%下降至82.08%。扫描电镜结果显示,经过最佳条件处理后,污泥絮体被破坏,减弱了对内部结合水的保持力,使污泥脱水性能得到改善。