Enhanced nitrogen removal upon the addition of volatile fatty acids from activated sludge by combining calcium peroxide and low-thermal pretreatments

This study investigated a combined low-thermal and CaO₂ pretreatment to enhance the volatile fatty acid (VFA) production from waste activated sludge (WAS). The fermentative product was added to a sequencing batch reactor (SBR) as an external carbon source to enhance nitrogen removal. The results showed that the combined pretreatment improved WAS solubilization, releasing more biodegradable substrates, such as proteins and polysaccharides, from TB-EPS to LB-EPS and S-EPS. The maximum VFA production of 3529 ± 188 mg COD/L was obtained in the combined pretreatment (0.2 g CaO₂/g VS + 70 °C for 60 min), which was 2.1 and 1.4-fold of that obtained from the sole low-thermal pretreatment and the control test, respectively. Consequently, when the fermentative liquid was added as an external denitrification carbon source, the effluent total nitrogen decreased to Class A of the discharge standard for pollutants in rural wastewater treatment plants in most areas of China.     

糖矿浆尿素复合秸杆处理剂的应用研究

用处理造纸废液的资源化产品──精矿浆与尿素混合处理秸杆,可提高秸杆作为家畜饲料的利用率。本实验用绵羊瘤胃内４８ｈ干物质消失率（ＤＭｄｐ）作为对家畜可利用程度的指标。用河北涿州市造纸厂的糖矿浆处理的稻草干物质消失率提高了４０％,中性洗涤纤维含量降低了２２．６％。稻草和玉米杆经糖矿浆尿素混合处理后饲喂绵羊日增重较氨化秸杆分别提高了２２．８％和９．２５％。     

环境科学研究中两变量非线性相关时的线性回归方程

以环境科学研究两变量非线性相关的问题为对象，讨论建立线性回归方程的方法。有绝对误差均方和最小的最小二乘法、相对误差最小的新回归法。以简易的方法，建立相关性好、误差小的回归方程。介绍了两变量各种非线性相关时的线性回归方程在环境科学研究中的应用。     

黄姜皂素废酸液在均相离子膜中渗析规律的研究

为了研究皂素水解废液在离子交换膜中的渗析规律,实验考察了废液中电导率、含盐量、氢离子浓度、硫酸盐浓度、Ca离子浓度、Mg离子浓度和有机物浓度随渗析时间的关系。研究结果表明:渗析时间进行100 h后,处理效果达到稳定状态;废液与渗析液的电导率几乎相等;含盐量、H+浓度、SO2-4浓度的分离效率分别为71%、62%、78%;Ca去除效果优于Mg去除效果;大部分有机物无法通过离子交换膜。     

Sea water intrusion in coastal areas of Yellow Seaand Bohai Sea

ＳｅａｗａｔｅｒｉｎｔｒｕｓｉｏｎｉｎｃｏａｓｔａｌａｒｅａｓｏｆＹｅｌｌｏｗＳｅａａｎｄＢｏｈａｉＳｅａＳｈｅｎｇＸｕｅｂｉｎ；ＳｕｎＪｉａｎｚｈｏｎｇ；ＤａｉＺｈａｏｈｕａ（ＲｅｓｅａｒｃｈＣｅｎｔｅｒｆｏｒＥｃｏ－ＥｎｖｉｒｏｎｍｅｎｔａｌＳｅ...     

培养提高建筑工程预算实践技能途径的探讨

高等职业教育的人才培养目标是为我国经济发展培养适应生产、建设、管理、服务第一线需要的应用性高素质人才，要求学生必须掌握够用的基础知识，必须具备较强的技术应用能力。本文以高职院校工程造价专业学生职业技能素质建设为起点，针对目前我国高职院校实践教学的现状，分析探讨了行之有效的强化培养高等职业院校工程造价专业实践技能素质的具体途径，旨在提高学生的实践能力和建筑工程预算实践技能。     

浅析垃圾渗滤液末端处理技术

从垃圾渗滤液的末端处理技术,即预处理、生物处理、后续处理三个方面分析了垃圾渗滤液的单独处理技术,并对渗滤液的回灌技术进行了论述。     

利用等离子技术治理再生纤维汽车内衬生产过程中的烟气

利用等离子技术,治理树脂聚合法生产再生纤维汽车内饰材料过程中产生的烟气,对等离子净化装置的结构参数、操作参数进行了优化,并对等离子体净化机理进行了分析。利用等离子技术,能够处理常规工艺设备无法治理的极微细可吸入颗粒物和气溶胶烟气;并可同时净化可吸入颗粒物和气态污染物。该设备结构简单、运行费用极低,可在产生烟气的很多行业和领域推广应用。     

Nutrient and tetracycline removal from simulated biogas slurry and biogas upgrading by microalgae cultivation under different carbon nanotubes concentrations

Environmental Science and Pollution Research - The present study sought to determine the effects of multi-walled carbon nanotubes (MWCNTs) concentrations (0–10 mg L?1) on tetracycline...     

Study on dust–gas coupling pollution law and selection of optimal purification distance of air duct during tunneling process

During the excavation of high gas mine, gas and dust often exist at the same time. In order to ensure that the gas concentration remains within a safe range and minimize the risk of workers’ pneumoconiosis, we simulated the interaction mechanism of airflow, gas, and dust, explored the pollution law of gas and dust, and obtained the optimal purification distance (L_p) by the CFD method. The reliability of the numerical simulation was verified by field measurements. Firstly, the properties of the gas and dust affected the structure of the airflow field. At the same time, the change in the airflow field affected the concentration distributions of the gas and dust. During the diffusion process, some high-risk regions in which the gas or dust concentrations exceeded 0.80% or 200 mg/m³, respectively, were discovered. Moreover, we have found that the airflow velocity in the top region of the tunnel and at the intersection corner between the cutting face and tunnel wall was the main factor affecting the purification effects. When L_p = 5–8 m, the gas concentration remained below 0.50%. When L_p = 6 m, the dust concentration reached a minimum of 287.5 mg/m³. Therefore, the optimal purification distance was determined to be 6 m; in which case, the gas and dust concentrations decreased by 32.84% and 47.02%, respectively.