关键词： anaerobic co-digestion   biodegradability   methane production   PHB   valorisation  

摘要： Bioplastics are designed to degrade at the end of their lifecycle, but effective management of their end-of-life phase and integration into existing organic waste management systems remain significant challenges. Some bioplastics decompose under anaerobic conditions, with the anaerobic digestion (AD) process being a potential solution for their disposal. AD is a promising technology for valorising organic wastes, enabling biomethane production, reducing carbon footprints, and promoting product circularity. This study focuses on evaluating the continuous co-digestion of bioplastics with mixed sludge from an urban wastewater treatment plant (WWTP). Polyhydroxybutyrate (PHB) was the selected bioplastic, as various studies have reported its high and rapid degradation under anaerobic mesophilic conditions. PHB's biodegradability under typical WWTP anaerobic digestion conditions (35 degrees C, 20-day retention time) was assessed in batch tests and the results indicate that PHB degradation ranged from 68 to 75%, depending on particle size. To further explore the potential of AD for PHB valorisation, the feasibility of anaerobic co-digestion of PHB with WWTP sludge was tested on a continuous laboratory scale using two digesters: a conventional digester (CSTR) and an anaerobic membrane bioreactor (AnMBR). The results indicated complete degradation of PHB, which led to higher biomethanisation percentages in both digesters, rising from 58% to 70% in the AnMBR and from 44% to 72% in the CSTR. The notable increase observed in the CSTR was attributed to changes in microbial populations that improved sludge biodegradability.

关键词： PLA/PHB polymer mixture   scaffold   3D printing   in vitro   biodegradation  

摘要： The advancing development in biomaterials and biology has enabled the extension of 3D printing technology to the bioadditive manufacturing of degradable hard tissue substitutes. One of the key advantages of bioadditive manufacturing is that it has much smaller design limitations than conventional manufacturing and is therefore capable of producing implants with complex geometries. In this study, three distinct blends of polylactic acid (PLA) and polyhydroxybutyrate (PHB) were produced using Fused Deposition Modeling (FDM) technology. Two of these blends were plasticized with oligomeric lactic acid (OLA) at concentrations of 5 wt% and 10 wt%, while the third blend remained unplasticized. Each blend was fabricated in two structural modifications: solid and porous. The biodegradation behavior of the produced specimens was examined through an in vitro experiment using three different immersion solutions: saline solution, Hank's balanced salt solution (HBSS), and phosphate-buffered saline (PBS). All examined samples were also subjected to chemical analysis: atomic absorption spectroscopy (AAS), scanning electron microscopy (SEM), and energy-dispersive spectrometry (EDS). The results of the degradation experiments indicated a predominantly better absorption capacity of the samples with a porous structure compared to the full structure. At the same time, the blend containing a higher concentration of OLA exhibited enhanced pH stability over the evaluation period, maintaining relatively constant pH values before experiencing a minor decline at the end of the study. This observation indicates that the increased presence of the plasticizer may provide a buffering effect, effectively mitigating the acidification associated with material degradation.

关键词： Halomonas   PHB   Nitrogen metabolism   Glutamine synthetase   Next generation industrial biotechnology   Metabolic engineering   Synthetic biology  

摘要： The trade-offs exist between microbial growth and bioproduct synthesis including intracellular polyester polyhydroxybutyrate (PHB). Under nitrogen limitation, more carbon flux is directed to PHB synthesis while growth is inhibited with diminishing overall carbon utilization, similar to the suboptimal carbon utilization during glycolysis-derived pyruvate decarboxylation. This study reconfigured the central carbon network of Halomonas bluephagenesis to improve PHB yield theoretically and practically. It was found that the downregulation of glutamine synthetase (GS) activity led to a synchronous improvement on PHB accumulation and cell growth under nitrogen non-limitation condition, increasing the PHB yield from glucose (g/g) to 85% of theoretical yield, PHB titer from 7.6 g/L to 12.9 g/L, and from 51 g/L to 65 g/L when grown in shake flasks containing a rich Nsource, and grown in a fed-batch cultivation conducted in a 7-L bioreactor also containing a rich N-source, respectively. Results offer better metabolic balance between glucose conversion efficiency and microbial growth for economic PHB production.

关键词： 制药厂   污泥   生产负荷   工艺   抗生素   生态风险  

摘要： 制药污水处理厂污泥是抗生素的主要储存库。制药污水中抗生素的浓度和种类与企业生产周期密切相关，存在明显的负荷差异。因此，研究考察了高、低生产负荷影响下不同污水处理工艺段污泥中抗生素的残留特征，并利用风险熵值（RQ）法评估了生化和物化污泥潜在的生态风险。结果表明，高、低生产负荷下污泥中检测出的11种抗生素种类相似，但浓度差异显著。高、低负荷条件下抗生素总检出浓度分别为401.72 μg/g和55.02 μg/g。生产负荷对废水处理工艺有一定的冲击力。高生产负荷下，不同工艺段的抗生素和水质参数之间的差异比低生产负荷下的差异更显著。制药过程中产生的抗生素在物化和生化脱水污泥中残留量依旧较高。污泥改良土中红霉素、罗红霉素和磺胺氯哒嗪对接收环境的水生生物构成高风险（RQ ＞10）。混合抗生素的生态风险远高于单一抗生素。制药厂大环内酯类和磺胺类抗生素是主要的风险因子，建议标记为优先控制污染物。不管是物化污泥还是生化污泥，都需要谨慎考虑污泥的最终出路。

关键词： 建筑工程   污水处理   环境保护   工艺技术   治理策略  

摘要： 随着城市化脚步的加快,我国建筑施工项目逐渐增多,相应的建筑污水排放成为影响建筑施工环境评价不可或缺的内容.面对建筑污水来源广、种类多、治理分散的问题,结合不同建筑污水种类和污染程度的特点,分析了几种不同的污水处理方案,提出了若干加强建筑污水综合治理的有效策略,期望对绿色建筑施工带来有益的思考.

关键词： 水质预测   特征工程   机器学习   深度学习   集成学习  

摘要： 传统水质监测手段耗时长、成本高且数据时效性差，污水处理系统参数反馈和调整周期长，在人工智能迅猛进展的背景下，构建基于数据驱动的水质预测技术有重要意义。本研究从大数据收集与处理层面出发，梳理了国内外水质数据收集、清洗策略以及特征工程等方法的特点和应用状况。在此基础上介绍了不同类型水质预测模型的预测效果与特点，统计回归模型、机器学习模型和深度学习模型都展现出一定的优势，但不同数据集质量上存在显著差异，难以获得普适的预测模型。结合大数据特征和数据集质量，采取合理的数据预处理手段，应用不同类型的预测方法或组合，可以显著提高模型预测准确性。最后综述了现阶段水质预测模型的应用现状、存在的问题以及未来发展方向，以期为水质预测模型研究、开发与应用提供参考。

关键词： 城市污水处理   污泥膨胀   自适应宽度学习算法   识别  

摘要： 针对污水处理过程的污泥膨胀难以精准识别的问题,提出了一种基于自适应宽度学习算法(adaptive broad learning algorithm,ABLA)的污泥膨胀识别方法.首先,结合城市污水处理过程的运行数据,采用主元分析法选取与污泥体积指数(sludge volume index,SVI)相关的特征变量;其次,建立了一种基于ABLA的污泥膨胀识别模型,利用自适应伪逆算法更新模型参数,提高了识别精度,并验证了模型的收敛性;最后,将所提模型应用于实际的污水处理过程中,利用污水处理厂的实际运行数据对其进行实验验证.实验结果表明,基于ABLA的污泥膨胀识别模型能够实现污泥膨胀的精准识别.

关键词： High glucose   Advanced glycosylation end products   Diabetic encephalopathy   Prohibitin 2   Mitophagy  

摘要： Diabetic encephalopathy (DE) is a severe complication of diabetes, but its pathogenesis remains unclear. This study aimed to investigate the roles and underlying mechanisms of high glucose (HG)- and advanced glycosylation end product (AGE)-induced oxidative stress (OS) in the cognitive decline in DE. The DE mouse model was established using a high-fat diet and streptozotocin, and its cognitive functions were evaluated using the Morris Water Maze, novel object recognition, and Y-maze test. The results revealed increased reactive oxygen species (ROS) generation, mitophagy inhibition, and decreased prohibitin 2 (PHB2) expression in the hippocampal neurons of DE mice and HG- or AGE-treated HT-22 cells. However, overexpression of PHB2 reduced ROS generation, reversed mitophagy inhibition, and improved mitochondrial function in the HG- or AGE-treated HT-22 cells and ameliorated cognitive decline, improved mitochondrial structural damage, and reversed mitophagy inhibition of hippocampal neurons in DE mice. Further analysis revealed that the Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2) pathway was involved in the HG- or AGE-mediated downregulation of PHB2 in HT-22 cells. These results demonstrate that HG- or AGE-induced OS inhibits the mitophagy of hippocampal neurons via the Keap1-Nrf2-PHB2 pathway, thereby contributing to the cognitive decline in DE.

关键词： 污水处理厂   碳排放核算   碳减排   分布式光伏发电  

摘要： 以西北地区某县城生活污水处理厂为研究对象，用排放因子法对污水厂碳排放量进行核算，研究结果表明：该污水厂冬季的直接碳排放量最高，为472 t，秋季直接碳排放量最低，为416 t，说明直接排放具有季节性的差异。间接排放主要由场内设备电耗产生，2021年因设备电耗产生的碳排放为2814t，占厂区总碳排放量的60.39%，药耗产生的碳排放最小，为75t。控制污水厂的碳排放应当从控制设备电耗入手。厂区内设备主要的耗电单元为鼓风机房，平均每月耗电量占厂区总耗电的29.07%，应列为主要管控对象。此外，厂区可用于布设分布式光伏发电设备的面积共计9479.96m2。经计算，日均发电量可达到6788.88 kW·h，占厂区总日均用电的74.57%，可减少厂区总碳排放的45.66%。从投资成本计算，仅需4.83年即可完成成本回收，说明污水处理厂布设分布式光伏，在有效减少碳排放的同时，长远看还具有一定的经济效益。

关键词： 污水处理厂   碳流向   外碳源减量  

摘要： 研究以采用倒置A2/O（缺氧-厌氧-好氧）工艺的重庆ST污水处理厂为对象，通过持续的取样分析以及内部过程核算，分析了污水处理厂进水中碳源的流向，结果表明，在所研究对象污水处理厂中，生化池的输入BOD总量约为99.0 mg/L（含进水碳源以及外加碳源），其中46.1 mg/L用于了反硝化脱氮，占47%；厌氧池中磷的释放消耗碳源7.44 mg/L，占7%，缺氧/厌氧池中微生物因同化作用所消耗的BOD占24%，好氧阶段的BOD氧化占22%。以上碳源的消耗中，反硝化对碳源的需求不可或缺，缺氧/厌氧阶段的同化作用耗碳不可避免；而厌氧释磷耗碳和好氧耗碳过程则可以在实际工程中通过运行优化予以削减甚至避免。这为后续的外碳源的减量方向提供了依据。