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311.
针对造纸废水的特点,应用水解酸化+氧化沟生物处理+强氧化深度处理的治理工艺对造纸中段废水进行处理。对实际运行效果的检测表明,经处理后的中段废水可达标排放,实现中段水的循环利用,具有较大的环境效益、经济效益和社会效益。 相似文献
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介绍了辽河流域造纸废水污染的历史概况和治理现状,通过对造纸企业停产整顿前后河流水质变化的对比分析,论证了辽河流域造纸废水入河污染物对河流水质的显著影响。并进一步探讨了造纸废水污染的防治对策。 相似文献
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Masahiro Shimada Takahiko Iida Kensuke Kawarada Yoshifumi Chiba Toshihiro Mamoto Takayuki Okayama 《Journal of Material Cycles and Waste Management》2000,2(2):100-108
In an earlier report, we presented a method for preparing activated carbon from waste newspaper as a way to recycle used paper
for a purpose other than producing raw material for paper-making. In this article, we consider the porous structure of the
activated carbon that affects its adsorption properties for various substances. The specific surface area of activated carbon
prepared from waste newspaper was 838 m2/g, the micropore volume was 0.368 ml/g, and the mesopore volume was 0.138 ml/g, which is about the same as commercially available
activated carbon. The activated carbon prepared from waste newspaper usually has a high content of ash, which makes little
contribution to the adsorption properties. In particular, as compared with reagent-activated carbon, the quantities of mesopores
with a pore radius of 3–25 nm and macropores with a pore radius of 25–250 nm were 8 and 14 times larger, respectively. Activated
carbon prepared from waste newspaper has a well-developed porous structure, particularly in the mesopore and macropore ranges.
Received: July 12, 1999 / Accepted: March 8, 2000 相似文献
318.
Matthew S. Spurlin Brent W. Barker Bradley D. Cross Craig E. Divine 《补救:环境净化治理成本、技术与工艺杂志》2019,29(2):63-73
Nuclear magnetic resonance (NMR) geophysical tools have been widely used in the petroleum exploration industry since the 1960s and have improved significantly in the last two decades. These tools can provide estimates of bulk porosity and fluid content, quantification of bound versus mobile fluids, and estimates of hydraulic conductivity (K). Although the size and cost of oil‐field tools historically limited their use for near‐surface applications, smaller and more economical downhole NMR logging tools are now available for detecting and characterizing the formation water content and K to support environmental and groundwater resource investigations. These tools can be deployed using direct‐push drilling techniques or they can be lowered into existing open borings or wells with nonconductive polyvinyl chloride casings and screens. In many cases, using the tool in existing wells offers a safer and more cost‐effective alternative compared to drilling new boreholes. For environmental investigations, NMR can provide useful high‐resolution quantitative hydrostratigraphic information that can provide additional valuable data to further inform and refine the conceptual site model. This paper highlights several NMR field investigations that demonstrate the viability of this technology as a site characterization tool for near‐surface investigations. NMR measurements were compared to data from lithologic logs, cone penetrometer testing data, and prior field hydraulic tests. Use of NMR to detect vadose zone water, including previously unidentified perched groundwater zones, provided hydrostratigraphic details that could not be gleaned from historical well drilling logs and were used to evaluate drainable pore water versus pore water bound in small pores by capillary forces or electrochemically clay‐bond water. NMR also produced K estimates similar to those from conventional hydraulic tests, but the improved vertical resolution from NMR provided additional information regarding the vertical heterogeneity of the formation along the entire length of the well or borehole. Additionally, bench‐scale tests are presented that confirm the capability for NMR to reliably detect and quantify light nonaqueous phase liquid saturation (specifically diesel fuel and weathered gasoline) in situ. The field tests combined with bench‐scale testing results affirm the applicability and potential for NMR as a practical characterization tool that should increasingly be utilized in environmental investigations. 相似文献
319.
为净化糖厂滤泥,使其得到更好的资源化利用,研究pH、时间、温度、转速和接种量对霉菌净化糖厂滤泥效果的影响。在单因素基础之上,选取温度、pH和接种量为自变量,耗糖量为响应值,采用响应面优化法优化霉菌净化糖厂滤泥的条件。利用Box-Behnken设计和方差分析,研究各自变量及其交互作用对耗糖量的影响,模拟得到二次多项式回归方程的预测模型。结果表明,温度30℃,pH为8,接种量为6%为最佳优化条件,在此条件下,耗糖量的实际值为1 040 mg/20g滤泥,理论值为1 061.39 mg/20 g滤泥,两者的相对误差为1.97%。二次响应曲面方差分析结果表明,回归模型达到显著性水平,在研究区域内拟合较好,模型的精密度、可信度和精确度均在可行范围内。说明响应面法优化霉菌净化糖厂滤泥的条件切实可行。 相似文献
320.
选取典型的生活污水污泥和造纸污泥进行干燥特性分析,对比了干燥过程中的水分析出特性、污泥球体中心温度变化和物理性质变化。结果表明,无论是生活污水污泥还是造纸污泥,在干燥过程中等速干燥阶段都不明显,而造纸污泥更快达到最大干燥速率,更快进入降速干燥阶段;造纸污泥球的中心温度在高温(250℃)干燥条件下还存在超温的现象,即污泥球中心温度在某段时间内高于干燥温度,形成了蓄热内核;干燥过程中,造纸污泥水分的析出是依靠层层传递,污泥球结构稳定收缩,缩容率相对较小,最终收缩成一硬核;生活污水污泥在干燥中缩容率相对较大,水分析出伴随着外壳的破裂,内层与外界可直接进行热传递交换,干燥后结团性能差,疏散度高,不易定型。 相似文献