Characteristics and management of domestic waste in a rural area of the Tibetan Plateau

In the rural area of the Tibetan Plateau (RATP), the characteristics of domestic waste, people’s environmental awareness, people’s willingness to pay and their influence factors were firstly studied by questionnaires, field samplings and laboratory tests. The results showed that, in the RATP, the generation of domestic waste was 85 g?d-1 per capita and it was mainly composed of plastics, inert waste, kitchen waste, glass and paper. The waste bulk density, moisture content, ash, combustible and low calorific value were 65 kg?m-3, 19.25%, 44.90%, 35.85% and 10,520 kJ?kg-1 respectively. These characteristics are influenced by income sources and geographical position to some extent. Classified collection should be promoted widely on the household and the village basis. Compost, fermentation, landfill, bioreactor landfill and semi-aerobic landfill have been approved as effective techniques to treat domestic waste, except incineration. The distance of 50–800 m between each collection facility and the disposal fee of around $0.8 per month per household are suggested. For suburbs or large population villages, it’s better to treat domestic waste by the centralized way. But for the remote rural areas, a decentralized way is proposed. Significantly, the educational and economic influence should be considered into an effective domestic waste management program.

Implications:?The current situatio n of the environment in the rural areas of the Tibetan Plateau (RATP) was surveyed. There, the generation of organics and moisture of domestic waste were low but ash, recyclables, and combustibles were high. People’s knowledge of domestic waste was absent but their participation in management was strong. Based on the current situation, compost, fermentation, and landfill were effective but incineration was inappropriate. Also, a localized mini landfill for a cluster of villages and or settlements was the best method there.     

浊漳河山西省潞城市境内段河流生态健康评价研究

浊漳河山西省潞城市境内干流段及南源段河道生态环境目前最突出的问题在于水质恶化、水量减少以及生物多样性衰退。本文从水质、水量、生物状况三个要素出发,通过建立浊漳河潞城市境内河段的水生态健康评价体系,对浊漳南源及干流段进行了生态健康诊断。结果显示,浊漳干流段生态健康总指数36.74,呈生态病态状;南源段生态健康总指数60.03,呈基本健康状态。据此,浊漳河潞城境内段目前的核心问题是生态恢复问题,应当针对其存在的问题选择适当的生态修复模式,采取相应的生态环境管理方法,把生态系统的恢复和重建作为其流域治理的最终目标。     

UV-Fenton体系预处理四氢呋喃废水实验研究

采用UV-Fenton体系预处理四氢呋喃废水,实验结果表明,pH值、反应时间、Fe2+和H2O2投加量等因素对处理效果有较大的影响。实验确定的最佳反应条件为:原水pH=5,Fe2+投加量2.5 mmol/L,H2O2投加量12 mmol/L,反应时间90 min,连续曝气,在此条件下,COD去除率可达85%左右。经UV-Fenton体系处理后,废水的B/C值由0.16增至0.47,可生化性提高,可满足后续生化处理的要求。     

某生活垃圾卫生填埋场渗滤液的梯度分离与表征

目前,渗滤液中污染物的粒度分布及其在渗滤液污染控制中的作用日益受到关注。通过系列微滤膜(1.2μm及0.45μm)对某生活垃圾卫生填埋场渗滤液各处理单元的渗滤液进行梯度分离,发现悬浮物对COD、浊度的影响较大;COD主要在胶体态和可溶解态间分配,不同渗滤液中的分配情况不同;磷主要与胶体、悬浮物以各种形式结合而存在;细胶粒和溶解态等小分子对TN的贡献大;不同粒度物质对pH的影响不明显;总残渣在可溶态组分中所占比例较大。膜微滤处理渗滤液可以有效的去除一部分物质,使COD、TP、TN、浊度、电导率都有不同程度的降低,pH逐渐升高,但对总N、残渣的去除效果不好。     

无硫膨胀石墨的制备及吸油性能

通过单因子实验考察了无硫膨胀石墨制备过程中氧化剂及插层剂用量、氧化反应及插层反应时间、氧化反应及插层反应温度对无硫膨胀石墨膨胀体积的影响。通过正交实验确定了制备无硫膨胀石墨的最优条件是:石墨(g)∶浓硝酸(mL)∶30%H2O2(mL)∶乙酸酐(mL)=1∶2.25∶0.25∶0.6,在30℃条件下氧化反应60 min,加入插层剂后在60℃条件下插层反应90 min,此条件无硫膨胀石墨的膨胀体积达317 mL/g使用XPS、FT-IR、XRD和SEM对无硫膨胀石墨进行了表征并对其吸油性能和再生性能进行了研究。结果表明,所制备无硫膨胀石墨对原油和柴油的最大吸附量分别为66.3 g/g和62.7 g/g。吸附原油后的无硫膨胀石墨抽滤再生后首次再生率为49.1%,原油的回收率为64.5%。     

氮掺杂TiO2可见光光催化剂的制备及性能

以尿素和钛酸丁酯为原料,通过溶胶-凝胶法低温下制备了高可见光催化活性的氮掺杂TiO2(NDT)光催化剂,采用XRD、TEM、BET和UV-Vis DRS等测试手段对其进行了表征,并在自制光催化反应器中降解甲基橙评价了样品的光催化活性。结果表明,当氮与钛的摩尔比为0.5∶1时,350℃焙烧的样品(NDT350)具有最佳的可见光光谱吸收和光催化活性,该催化剂为锐钛矿晶相,平均粒径为21 nm,比表面积为89.13 m2/g。可见光辐照下,NDT350降解甲基橙的表观反应速率常数为1.381×10-2min-1,是商业P25催化剂的16.85倍。NDT350优良的可见光催化活性与其大的比表面积和强烈的可见光光谱吸收有关。     

脂肽类生物表面活性剂液体发酵条件的响应面优化

通过Plackett-Burman和Box-Behnken实验对解淀粉芽孢杆菌XZ-173液体发酵生产表面活性素进行了响应面优化研究。首先使用Plackett-Burman实验对影响表面活性素产量的17个因素进行显著性筛选,结果表明,MnSO4、CuSO4、温度和转速为显著性因素。再运用Box-Behnken实验对这4个显著因素的取值进一步优化,得到各因素优化后的数值分别为4.4 mg/L(MnSO4)、0.18 mg/L(CuSO4)、29℃(温度)和163 r/min(转速)。响应面分析结果表明:该菌株产生表面活性素的最佳培养基为:葡萄糖15 g/L,蛋白胨5 g/L,L-谷氨酸钠6 g/L,KH2PO40.8 g/L,MgSO40.4 g/L,KCl 0.4 g/L,酵母提取物3 g/L,L-苯丙氨酸2.5 mg/L,MnSO44.4 mg/L,CuSO40.18 mg/L,FeSO40.12 mg/L;最适培养条件:pH 7.5,温度29℃,转速163 r/min,接种量5%,装液量50 mL/250 mL,摇床培养36 h。在优化后的条件下,表面活性素实际产量为336 mg/L,实际实验结果与模型预测结果相一致。表面活性素采用HPLC技术分离,发现其在浓度仅为50 mg/L时EI24就可达到70%以上,反映了表面活性素优异的乳化活性以及广阔的应用前景。     

实时荧光定量PCR对A2/O短程硝化系统内氨氧化菌的定量分析

通过控制好氧区低DO浓度以及缩短好氧实际水力停留时间(actual hydraulic retention time,AHRT),在处理低C/N比实际生活污水的A2/O工艺中,成功启动并维持了短程硝化反硝化;系统亚硝酸盐积累率稳定维持在90%左右,氨氮去除率在95%以上。通过提取富集氨氧化菌(ammonia oxidizing bacteria,AOB)的基因组DNA,经两次常规PCR扩增和琼脂糖凝胶电泳,以纯化回收的DNA扩增片段作为实时荧光定量PCR检测AOB数量的DNA标准品,建立了检测AOB数量的实时荧光定量PCR标准曲线。利用实时荧光定量PCR技术比较了A2/O系统在不同运行条件及亚硝酸盐积累率情况下AOB菌群数量。结果表明,随着系统亚硝酸盐积累率的上升,系统内AOB菌群数量也大幅上升。全程硝化和短程硝化时,系统内的AOB菌群数量分别为5.28×109cells/g MLVSS和3.95×1010cells/g MLVSS。此外,亚硝酸盐积累率的下降相对于AOB菌群数量的下降有一定的滞后性。     

Development Potentials and Policy Options of Biomass in China

Biomass, one of the most important renewable energies, is playing and will continue to play an important role in the future energy structure of the world. This article aims to analyze the position and role, assess the resource availability, discuss the geographic distribution, market scale and industry development, and present the policy options of biomass in China. The resource availability and geographical distribution of biomass byproducts are assessed in terms of crop residues, manure, forest and wood biomass byproducts, municipal waste and wastewater. The position of biomass use for power generation is just next to hydropower among types of renewable energy in China. The potential quantity of all biomass byproducts energy in 2004 is 3511 Mtce (Mtce is the abbreviation of million tons of coal equivalents and 1 Mtce is equal to10⁶ tce.), while the acquirable quantity is 460 Mtce. Biomass energy plays a critical role in rural regions of China. The geographical distribution and quantity of biomass byproducts resources depends mainly on the relationship between ecological zones and climate conditions. Our estimation shows that the total quantity of crop residues, manure, forest and wood biomass byproducts, municipal waste and wastewater resources are 728, 3926, 2175, 155 and 48240 Mt (million tons), respectively. Crop residues come mainly from the provinces of Henan, Shandong, Heilongjiang, Jilin and Sichuan. All manure is mainly located in the provinces of Henan, Shandong, Sichuan, Hebei and Hunan. Forest and wood biomass byproducts are mainly produced in the provinces or autonomous regions of Tibet, Sichuan, Yunnan, Heilongjiang and Inner Mongolia, while most of municipal waste mainly comes from Guangdong, Shandong, Heilongjiang, Hubei and Jiangsu. Most of wastewater is largely discharged from advanced provinces like Guangdong, Jiangsu, Zhejiang, Shandong and Henan. Biomass byproducts’ energy distribution also varies from province to province in China. Based on the analysis of the market scale and industry development, the article argues that China’s biomass energy industry is still at a very early stage of development and that Feed-in Tariffs (FIT) might be the best policy option for China to promote its development of biomass energy. A successful enforcement of FIT in China needs some policy combination of special capital subsidies, R&D funding, tax incentives and pricing.     

江苏沿海风能资源禀赋与开发利用研究

江苏沿海地区拥有丰富的风能资源,开发前景十分广阔,尤其是中部、南部地区拥有广阔的沿海滩涂和辐射沙洲,建设沿海风电场的条件优越,是打造江苏"海上三峡"新能源基地的希望所在。阐述了江苏沿海风能资源开发的重要意义,分析了沿海风能资源的禀赋与时空分布特点,指出江苏沿海岸区风能资源丰富,且沿海滩涂宽广,是建立大型风力发电场的理想之地,在此基础上提出发展江苏沿海绿色能源基地的构想。