兴凯湖水体磷形态特征及与气候变化的响应关系

兴凯湖是亚洲东北部最大的淡水湖,水体总磷（TP）浓度超标是近年来兴凯湖水质下降的主要原因,气候可能对区域水质有重要的影响。以兴凯湖中国湖区为研究区域,通过分析兴凯湖水体磷素时空变化特征,探究其主要组成形态,明确区域内气候因子变化对兴凯湖水体TP浓度的影响。结果表明：1）2010—2021年,兴凯湖水体TP浓度整体呈先降后升的趋势,冰封期水质状况优于非冰封期,大兴凯湖TP浓度相较于小兴凯湖更高。2）2022年5月磷形态数据表明,大、小兴凯湖水体TP主要由颗粒态磷（PP）组成（占比为60%和76%）,PP是大、小兴凯湖TP超标的主要形态;小兴凯湖的PP与溶解磷浓度表现为北部高于南部,大兴凯湖PP浓度总体表现为东部高于西部,溶解磷浓度则呈相反趋势。3）近年来兴凯湖流域的气温及降水量均呈上升趋势,小兴凯湖TP浓度与气温、降水量均呈显著正相关,气温与降水增加可能会导致更多的营养盐进入水体,造成水质下降;大兴凯湖TP浓度与气候变化无明显相关性,但小兴凯湖与大兴凯湖的TP浓度之间呈显著正相关,表明大兴凯湖受区域气候变化影响较小,但其水质状况与小兴凯湖有紧密的关联性。无论冰封期还是非冰封期,小兴凯湖水质均优于大兴凯湖,作为大兴凯湖的前置湖泊,小兴凯湖在净化上游流域面源污染方面起到了重要的作用。

     

响应面法优化负压原位碱度脱氨处理垃圾焚烧厂渗滤液AnMBR出水

针对垃圾焚烧厂渗滤液厌氧膜生物反应器(anaerobic membrane bioreactor, AnMBR)出水中仍含有高浓度氨氮,无法满足现行排放标准的问题,采用负压原位碱度脱氨工艺对AnMBR出水进行进一步处理;考察了温度、真空度和脱氨时间3个因素对负压原位碱度脱氨工艺氨氮去除率的单独作用,分析了不加碱前提下脱氨过程中体系pH的变化,并利用响应面学的方法对3因素的交互作用进行了探讨和分析。单因素实验结果表明：各因素在响应范围内对氨氮的去除有显著性影响,在温度为60 ℃、真空度为−0.08 MPa、脱氨时间为2 h时,氨氮去除率达到75.5%;在负压原位碱度脱氨过程中,AnMBR出水中自有碱度对pH具有显著调控作用,碳酸氢根水解致使反应体系pH上升进而促进氨氮脱除;利用响应面法探讨了各因素对氨氮去除率的影响,其对于氨氮去除率的贡献排序为温度>真空度>脱氨时间;确定负压原位碱度脱氨的最佳时间为3.5 h,温度为59 ℃,真空度为−0.079 MPa,该条件下氨氮去除率为92%以上,并对该模型进行了实验验证;响应面法的预测值与实验值吻合较好。由此可知,通过负压原位碱度脱氨可以去除垃圾焚烧厂渗滤液AnMBR出水中大部分氨氮,并大幅提高C/N比,为后续与适当的生化处理工艺组合处理奠定了良好基础。该研究结果可为负压原位碱度脱氨法处理垃圾焚烧厂渗滤液AnMBR出水中氨氮的工业化应用提供参考。     

餐厨垃圾两相与单相厌氧消化过程参数分析

在(55±0.2) ℃温度下,以餐厨垃圾为原料,分别进行两相与单相厌氧消化实验,两相实验设置不同初始pH的反应组,比较两相与单相厌氧消化的产气效率、有机酸、营养物质和酶活性等的变化。结果表明,餐厨垃圾两相厌氧消化可以提高产甲烷效率,初始pH 8.5餐厨垃圾组的甲烷产量最高为178.3 mL/g COD,比单相厌氧消化提高了338%;另外,两相厌氧消化中氢气最高可达14.12 mL/g TS。餐厨垃圾两相厌氧消化产酸相的初始pH会影响产氢和产甲烷的效率,氢气和甲烷的产量随初始pH的升高而呈增加趋势。淀粉酶活性在两相实验组的产酸相及单相实验组均呈现先升后降的变化,最高活性分别为0.542 mg/(mL·min)和0.298 mg/(mL·min);蛋白酶活性在产酸相达到最高,为1.70 μg/(mL·min);脱氢酶活性在初始pH为9.0的实验组达到最高,为145 μg/(mL·h),分别是空白和单相实验组的113.3%和120.8%。     

含油污泥热解处理的试验与应用

介绍了欢三联含油污泥热解处理工程的工艺流程、技术要点、设计参数、运行效果和效益情况。调试工作表明,热解炉系统工艺作为一个整体,能够稳定有效运行,残渣的测验结果表明,残渣可以达到无害化程度,含油率小于0.3%(满足GB 4284-84《农用污泥中污染物控制标准》的要求)。以12t/d的处理量运行,能耗成本为74.47元/t,产生的经济效益为125.50元/t,同时产生较好的社会效益。另外,热解固态产物也有较好的利用价值,可以进一步研究利用。     

复合生物反应器工艺对化纤废水的处理研究

在普通活性污泥系统的曝气池中投加一定量的填料构成复合生物反应器 ,可以增加曝气池中的生物体量至 6g/L左右 ,在HRT为 8h ,泥龄为 5d时 ,CODCr、氨氮的去除率分别提高了 2 0 %和9.6% ,容积负荷对复合生物反应器的脱氮能力影响较小。该工艺对污泥膨胀有较好的控制     

Identical full-scale biogas-lift reactors (BLRs) with anaerobic granular sludge and residual activated sludge for brewery wastewater treatment and kinetic modeling

Two identical full-scale biogas-lift reactors treating brewery wastewater were inoculated with different types of sludge to compare their operational conditions, sludge characteristics, and kinetic models at a mesophilic temperature. One reactor （R1） started up with anaerobic granular sludge in 12 weeks and obtained a continuously average organic loading rate （OLR） of 7.4 kg chemical oxygen demand （COD）/（m3.day）, COD removal efficiency of 80%, and effluent COD of 450 mg/L. The other reactor （R2） started up with residual activated sludge in 30 weeks and granulation accomplished when the reactor reached an average OLR of 8.3 kg COD/（m^3·day）, COD removal efficiency of 90%, and effluent COD of 240 mg/L. Differences in sludge characteristics,biogas compositions, and biogas- lift processes may be accounted for the superior efficiency of the treatment performance of R2 over R1. Grau second-order and modified StoverKincannon models based on influent and effluent concentrations as well as hydraulic retention time were successfully used to develop kinetic parameters of the experimental data with high correlation coefficients （R2 〉 0.95）, which further showed that R2 had higher treatment performance than R1. These results demonstrated that residual activated sludge could be used effectively instead of anaerobic granular sludge despite the need for a longer time.     

液桥凝聚用于办公废纸脱墨的研究

研究了混合办公废纸脱墨的选择性凝聚技术,在废纸浆中添加分散在水中并不与水相溶的长链烷作凝聚剂,这些凝聚剂选择性地将印刷墨粉通过液桥连结在一起,且形成大颗粒的球形聚团,再分选脱除.研究表明只需要加入占纸重量4%的廉价长链烷,即可获得95%以上的脱墨率.因此在混合办公废纸脱墨时加入凝聚剂进行液桥凝聚,可降低脱墨浆中的尘埃度并增加产品的白度.     

基于生态绿当量的开封土地利用研究

基于生态绿当量的提出与模型的建立,计算水田、旱田、园地和林地的生态绿当量,得到研究区域的综合绿当量,并将该值与以最佳森林覆盖率的生态优化标准进行比较。对研究区域的土地利用结构进行现状评价,在此基础上对研究区域土地利用结构进行优化调整。以开封为例,针对开封土地利用问题,提出优化方案,以期达到经济、社会和生态效益的统一。     

Understanding why consumers in China switch between wild,farmed, and synthetic bear bile products

An important rationale for legally farmed and synthetic wildlife products is that they reduce illegal, wild-sourced trade by supplying markets with sustainable alternatives. For this to work, more established illegal-product consumers must switch to legal alternatives than new legal-product consumers switch to illegal wild products. Despite the widespread debate on the magnitude and direction of switching, studies among actual consumers are lacking. We used an anonymous online survey of 1421 traditional Chinese medicine consumers in China to investigate switching among legal farmed, synthetic, and illegal wild bear bile. We examined the past consumption behavior, applied a discrete choice experiment framed within worsening hypothetical disease scenarios, and used latent class models to investigate groups with shared preferences. Bear bile consumers (86% respondents) were wealthier, more likely to have family who consumed bile, and less knowledgeable about bile treatments than nonconsumers. Consumer preferences were heterogenous, but most consumer preferences switched between bile types as disease worsened. We identified five distinct latent classes within our sample: law-abiding consumers (34% respondents), who prefer legal products and were unlikely to switch; two all-natural consumer groups (53%), who dislike synthetics but may switch between farmed and wild; and two nonconsumer groups (12%), who prefer not to buy bile. People with past experience of bile consumption had different preferences than those without. Willingness to switch to wild products was related to believing they were legal, although the likelihood of switching was mediated by preferences for cheaper products sold in legal, familiar places. We found that consumers of wild bile may switch to legal alternatives, given the availability of a range of products, whereas legal-product consumers may switch to illegal products if the barriers to doing so are small. Understanding preferences that promote or impede switching should be a key consideration when attempting to predict consumer behavior in complex wildlife markets.