同步短程硝化反硝化研究

分析了现有短程硝化反硝化工艺处理高浓度氨氮废水所存在的问题,试验利用序批式反应器(SBR)的内部水力特性对其进行改造,以畜禽养殖废水为研究对象,从宏观上创造同步硝化反硝化(SND)条件,并实现了同一反应器内短程硝化反硝化的同步进行,改造后系统pH值下降速度减缓,反硝化效率提高,最终出水的亚硝酸盐和硝酸盐浓度分别降低了39%和38%。     

废液和废水中分离回收钯研究进展

贵金属钯在工业生产中应用广泛,然而资源稀缺,价格昂贵,从二次资源中回收钯变得尤为重要。而冶金、电镀、PCB制造和核工业等工业活动中产生的含钯废液和废水是钯的一种占比较大的二次资源。不同来源的含钯废液和废水在钯含量、成分组成和其他特性等方面差异较大。基于40多篇国内外相关文献的分析,总结了从废液和废水中分离回收钯的已有技术,包括沉淀/置换法、萃取法、吸附法和生物法,对各种方法的原理、应用以及优缺点进行了简要介绍。对各种方法的近期研究进展进行了对比,未来研究方向进行展望,为废液和废水中钯的分离回收提供参考。     

厌氧反应器处理造纸废水工程实践

介绍了内循环(IC)厌氧反应塔和外循环(EC)厌氧反应塔应用于废纸抄造高强瓦楞原纸废水处理的工程实践及生产运行情况。生产运行数据表明,EC厌氧反应塔的处理效果优于IC厌氧反应塔,Ca~(2+)浓度对IC厌氧反应塔运行效果有较大的影响,而对EC厌氧反应塔影响较小;IC厌氧反应塔和EC厌氧反应塔可有效降解废纸造纸废水中的污染物,废水CODCr去除率可分别达到61.2%~77.4%和72.3%~87.9%,沼气产率为0.43 m~3/kg CODCr和0.45 m~3/kg CODCr;废纸造纸废水经初沉池、预酸化池、IC厌氧反应塔/EC厌氧反应塔、好氧曝气池、絮凝沉淀池、斜管沉淀池和高效纤维滤池工艺处理后达到国家《制浆造纸工业水污染物排放标准》(GB3544—2008)的一级标准,部分废水可回用到生产中去。     

A Wearable Respiration and Pulse Monitoring System Based on PVDF Piezoelectric Film

A novel wearable sensor system was developed for monitoring respiration and pulse using polyvinylidene fluoride (PVDF) piezoelectric films as sensor materials. Due to the different signal intensity between respiration and pulse, a “double-sided arch” structure and a “thin-shell” structure were designed and fabricated as substrates for the respiratory sensor and pulse sensor, respectively. These sensors installed on belts can be easily tied on the chest, abdomen, or wrist for comfortable fit. In order to obtain clear respiratory and pulse signals from the sensor patch, some high-quality signal processing modules were designed. The digital signals were transmitted to a computer via Bluetooth and displayed by LabVIEW software. The fundamental principle and functional verification of the developed sensor system were described in this study. By comparing the sensor signals from the proposed structure with those of flat structure, it can be concluded that the proposed sensor is more sensitive and stable than its flat counterpart. In addition, the whole sensor system has the features of ease of use and comfortable to wear. All these make the proposed sensor system a promising sensing device for respiration and pulse real time monitoring.     

Water exchange effect on eutrophication in landscape water body supplemented by treated wastewater

Artificial landscape water bodies filled by treated wastewater pose a risk of developing algal blooms due to high nutrient levels of treated wastewater. In this study, water exchange experiments were conducted using treated wastewater in an artificial landscape pond, and a eutrophication model was calibrated and applied to evaluate the effects of water exchange on algae growth in the pond. The results indicate that the joint dilution process and nutrient supply process of water exchange initially cause the algae level to rise and then rapidly decline as the hydraulic resident time (HRT) decreases, and HRT has a critical point at which the pond faces the highest risk of algal bloom. The study also indicates that phosphorus (instead of nitrogen) is the primary limiting factor of algae growth. Therefore, the critical HRT should be avoided and phosphorus is the target pollutant to be controlled in landscape pond water management.     

氯碱废水实施分质处理及回收利用技术的应用探讨

结合实际论述了氯碱废水的特点;分析了氯碱废水分质处理及回收利用的总体思路;探究了氯碱废水实施分质处理及回收利用技术的应用策略,以期对充分利用氯碱资源及保护环境有所帮助。     

改性粉煤灰吸附处理含铜废水的试验研究

分别用碱、酸、高温、超声波和助溶剂对粉煤灰进行改性,对每种改性粉煤灰吸附处理含铜废水进行研究。试验结果表明:其中碱、高温、助熔剂都可改性粉煤灰,碳酸钠助熔剂改性效果最好,其最佳反应时间是30min,最适宜反应温度是20℃,最适宜p H值是10。吸附过程符合Temkin和Langmuir吸附等温式。     

Sharpening polycrystalline phase boundary for potassium sodium niobate ceramics with MnF2 modification

The influence of anion on structure and performance is unclear in potassium sodium niobate ((K,Na)NbO₃; KNN)-based ceramics, while cation doping has been widely researched. Here, the phase structure and electrical properties are explored in MnF₂-doped KNN ceramics. Significantly, sharp rhombohedral–orthorhombic (R–O) and orthorhombic–tetragonal (O–T) phase boundary as well as reduced diffusion degree is exhibited in the ceramics along with little changed phase transition temperatures due to the optimized F⁻ content at O site, which is different from that of cation replacement for A and B sites. Notably, the domain wall motion is facilitated due to the increased A vacancy and decreased O vacancy along with strengthened polarity, originating from the higher valence state and electronegativity of F⁻ with respect to O²⁻. And then, enhanced ferroelectricity is realized via MnF₂ modification, the piezoelectricity is elevated in turn. This work presents a new idea of anion doping for controlling structure and properties in perovskite materials.