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931.
Dominic Bekoe Bo Zhang Matthew Scott Todd Abolghasem Shahbazi 《Journal of environmental science and health. Part. B》2018,53(2):145-151
Aerobic treatment of swine manure was coupled with anaerobic digestion and microalgal cultivation. A 14-day aerobic treatment reduced the total solid content of swine manure by >15%. Ammonia and carbon dioxide were stripped by the air supplied, and this off-gas was further used to aerate the culture of Chlorella vulgaris. The microalgal growth rates in Bristol medium and the wastewater with the off-gas increased from 0.08 to 0.22 g/L/d and from 0.15 to 0.24 g/L/d, respectively. Meanwhile, the aerobically treated swine manure showed a higher methane yield during anaerobic digestion. The experimental results were used to establish a demonstration unit consisting of a 100 L composter, a 200 L anaerobic digester, a 60 L tubular photobioreactor, and a 300 L micro-open raceway pond. 相似文献
932.
Huang Shaojian Dai Chunhao Zhou Yaoyu Peng Hui Yi Kexin Qin Pufeng Luo Si Zhang Xiaoshan 《Environmental science and pollution research international》2018,25(17):16548-16566
Environmental Science and Pollution Research - Plant leaves play a key role in the accumulation of PAHs, as they are able to capture PAHs from the air. In this paper, the mechanism, including... 相似文献
933.
Guochen Zhang Xin Zhao Danni Yang Xia Jiang Wenju Jiang 《Journal of the Air & Waste Management Association (1995)》2018,68(9):958-968
In this study, MnO2 and pyrolusite were used as the catalysts to prepare modified activated carbon, that is, AC-Mn and AC-P, respectively, from coals by blending method and steam activation. The Brunauer–Emmett–Teller (BET) results indicated that the AC-P had higher surface areas and micropore volumes than the AC-Mn with the same blending ratio. The relative contents of basic functional groups (i.e., C = O, π-π*) on AC-P were slightly lower than those on AC-Mn, while both contained the same main metal species, namely, MnO. The desulfurization results showed that with 3 wt% of blending ratio, AC-Mn3 and AC-P3 had higher sulfur capacities at 220 and 205 mg/g, respectively, which were much higher than for the blank one (149.6 mg/g). Moreover, the AC-P had relatively higher sulfur capacity than the AC-Mn with the same contents of Mn, which might be attributed to the existence of other metals in pyrolusite. After the desulfurization process, MnO were gradually transferred into MnSO4, and the relative contents of basic functional groups decreased evidently for both AC-Mn3 and AC-P3. The results demonstrated that pyrolusite could be one good alternative to MnO2 to prepare modified activated carbon for desulfurization.
Implications: MnO2 and pyrolusite were used as the additives to prepare modified activated carbon from coals by a blending method and by steam activation, that is, AC-Mn and AC-P, respectively. The AC-P had higher surface areas and micropore volumes than the AC-Mn with the same blending ratio. The AC-Mn and AC-P had higher sulfur capacities than a blank one. Moreover, the AC-P had relatively higher sulfur capacity than the AC-Mn with the same contents of Mn. The results demonstrated that pyrolusite could be one good alternative to MnO2 to prepare modified activated carbon for desulfurizatio. 相似文献
934.
Fangli Su Tieliang Wang Haozhen Zhang Zhi Song Xue Feng Kan Zhang 《Environmental monitoring and assessment》2018,190(6):365
The aims of the present investigation were to reveal the distribution and enrichment characteristics of copper in soil and Phragmites australis of Liao River estuary wetland. The concentrations of copper in root, stem, leaf, and ear of Phragmites australis as well as in soil were determined to study the absorption capacity of copper by wild Phragmites australis of Liao River estuary wetland. The study was carried out at test pool of the Shenyang Agricultural University, and the experimental materials (soil, irrigating water and Phragmites australis) were derived from Liao River estuary wetland. The concentrations of copper in soil and Phragmites australis were 16.4441 to 49.0209 mg/kg and 0.8621 to 89.5524 mg/kg, respectively. The results indicated that the enrichment coefficients of copper in different tissues of Phragmites australis changed with the growth of Phragmites australis. The results revealed that the enrichment coefficients of copper in the whole Phragmites australis were greater than 1 at each growing stage of the Phragmites australis. The results also showed that the transfer coefficients of Phragmites australis to copper changed with the growth of Phragmites australis. The results revealed that the Phragmites australis had a good removal effect on copper from soil and had some characteristics of copper hyperaccumulator. 相似文献
935.
Spatial distribution characteristics of soil organic carbon in subtropical forests of mountain Lushan,China 总被引:2,自引:0,他引:2
Fazhan Yu Zhongqi Zhang Longqian Chen Jinxin Wang Zhengping Shen 《Environmental monitoring and assessment》2018,190(9):545
The study on the spatial distribution of forest soil organic carbon (SOC) is of great significance for accurate assessment of carbon storage in forest ecosystems. In the present study, by taking eight kinds of forest soils of Mountain Lushan in the subtropical area as the research object, we studied the spatial distribution characteristics of SOC in this mountainous area. The results showed that the SOC content and SOC density (SOCD) of main forest types in the Mountain Lushan were lower than the national and the world average. The soil layer of Lushan forest was thinner, and the SOC and active SOC (ASOC) contents of different forest types and SOCDs are the highest in the surface soil. SOCD of the topsoil accounts for 32.64–54.03% of the total SOCD in the whole soil profile. Surface litter is an important source of SOC, and the different vegetation types are the important reason for the different spatial distribution of SOC in this area. Soil SOC contents in the high-altitude forest (bamboo forest, deciduous broadleaf forest, Pinus taiwanensis forest, evergreen-deciduous forest, and coniferous-broadleaved mixed forest) were higher than those in the low-altitude forest (evergreen broadleaf forest, shrub, and Pinus massoniana forest). However, the difference in SOC content exhibited at the altitude gradient is significantly lower than that in SOC in the soil profile. This indicates that both soil depth and elevation are the important factors that affected SOC distribution. However, the influence of soil depth on spatial distribution of SOC may be more complex than that of altitude. Vegetation types and soil properties are the main reasons for the large differences of reduction rate in the contents of SOC and ASOC. 相似文献
936.
生物难降解有机污染物的治理对策 总被引:11,自引:0,他引:11
针对废水中难降解化学合成有机污染物的种类和数量不断增加,生物处理出水达标困难的现状,总结了国内外的经验和研究成果,对现有处理装置改造提出了若干建议,并介绍了几种国外废水处理新技术。 相似文献
937.
O/W型乳化液的处理 总被引:3,自引:0,他引:3
采用药剂破乳-电解破乳工艺处理O/W型乳化液,药剂破乳选用聚合硫酸铁为破乳剂,破乳时最佳PH为8,聚合硫酸铁的最佳投量为1500mg/L,电解破乳选用铁作阳极,铝作阴极,电流密度0.86A/dm^2,极距25mm,电解时间3h。在上述条件下,破乳效果良好,出水清澈透明,COD总去除率可达到96-97%。 相似文献
938.
我国农药工业三废治理方法 总被引:12,自引:0,他引:12
详细介绍了我国农药生产中排放的废水、废气、废渣的常用治理技术,通过改进生产工艺和回收利用减少三废的实例,以及主要品系农药生产废水治理方法选择的思路。 相似文献
939.
Zhisheng Zhang Guenter Engling Chuan-Yao Lin Charles C.-K. Chou Shih-Chun C. Lung Shih-Yu Chang Shaojia Fan Chuen-Yu Chan Yuan-Hang Zhang 《Atmospheric environment (Oxford, England : 1994)》2010,44(26):3187-3195
Intensive measurements of aerosol (PM10) and associated water-soluble ionic and carbonaceous species were conducted in Guangzhou, a mega city of China, during summer 2006. Elevated levels of most chemical species were observed especially at nighttime during two episodes, characterized by dramatic build-up of the biomass burning tracers levoglucosan and non-sea-salt potassium, when the prevailing wind direction had changed due to two approaching tropical cyclones. High-resolution air mass back trajectories based on the MM5 model revealed that air masses with high concentrations of levoglucosan (43–473 ng m?3) and non-sea-salt potassium (0.83–3.2 μg m?3) had passed over rural regions of the Pearl River Delta and Guangdong Province, where agricultural activities and field burning of crop residues are common practices. The relative contributions of biomass burning smoke to organic carbon in PM10 were estimated from levoglucosan data to be on average 7.0 and 14% at daytime and nighttime, respectively, with maxima of 9.7 and 32% during the episodic transport events, indicating that biomass and biofuel burning activities in the rural parts of the Pearl River Delta and neighboring regions could have a significant impact on ambient urban aerosol levels. 相似文献
940.
Yang Zhang X.-Y. Wen C.J. Jang 《Atmospheric environment (Oxford, England : 1994)》2010,44(29):3568-3582
The chemistry–aerosol–cloud–radiation–climate feedbacks are simulated using WRF/Chem over the continental U.S. in January and July 2001. Aerosols can reduce incoming solar radiation by up to ?9% in January and ?16% in July and 2-m temperatures by up to 0.16 °C in January and 0.37 °C in July over most of the continental U.S. The NO2 photolysis rates decrease in July by up to ?8% over the central and eastern U.S. where aerosol concentrations are high but increase by up to 7% over the western U.S. in July and up to 13% over the entire domain in January. Planetary boundary layer (PBL) height reduces by up to ?23% in January and ?24% in July. Temperatures and wind speeds in July in big cities such as Atlanta and New York City reduce at/near surface but increase at higher altitudes. The changes in PBL height, temperatures, and wind speed indicate a more stable atmospheric stability of the PBL and further exacerbate air pollution over areas where air pollution is already severe. Aerosols can increase cloud optical depths in big cities in July, and can lead to 500–5000 cm?3 cloud condensation nuclei (CCN) at a supersaturation of 1% over most land areas and 10–500 cm?3 CCN over ocean in both months with higher values over most areas in July than in January, particularly in the eastern U.S. The total column cloud droplet number concentrations are up to 4.9 × 106 cm?2 in January and up to 11.8 × 106 cm?2 in July, with higher values over regions with high CCN concentrations and sufficient cloud coverage. Aerosols can reduce daily precipitation by up to 1.1 mm day?1 in January and 19.4 mm day?1 in July thus the wet removal rates over most of the land areas due to the formation of small CCNs, but they can increase precipitation over regions with the formation of large/giant CCN. These results indicate potential importance of the aerosol feedbacks and an urgent need for their accurate representations in current atmospheric models to reduce uncertainties associated with climate change predictions. 相似文献