Characteristics of anoxic phosphors removal in sequence batch reactor

The characteristics of anaerobic phosphorus release and anoxic phosphorus uptake were investigated in sequencing batch reactors using denitrifying phosphorus removing bacteria （DPB） sludge. The lab-scale experiments were accomplished under conditions of various nitrite concentrations （5.5, 9.5, and 15 mg/L） and mixed liquor suspended solids （MLSS） （1844, 3231, and 6730 mg/L）. The results obtained confirmed that nitrite, MLSS, and pH were key factors, which had a significant impact on anaerobic phosphorus release and anoxic phosphorus uptake in the biological phosphorous removal process. The nitrites were able to successfully act as electron acceptors for phosphorous uptake at a limited concentration between 5.5 and 9.5 mg/L. The denitrification and dephosphorous were inhibited when the nitrite concentration reached 15 mg/L. This observation indicated that the nitrite would not inhibit phosphorus uptake before it exceeded a threshold concentration. It was assumed that an increase of MLSS concentration from 1844 mg/L to 6730 mg/L led to the increase of denitrification and anoxic P-uptake rate. On the contrary, the average P-uptake/N denitrifying reduced from 2.10 to 1.57 mg PO4^3--P/mg NO3^--N. Therefore, it could be concluded that increasing MLSS of the DEPHANOX system might shorten the reaction time of phosphorus release and anoxic phosphorus uptake. However, excessive MLSS might reduce the specific denitrifying rate. Meanwhile, a rapid pH increase occurred at the beginning of the anoxic conditions as a result of denitrification and anoxic phosphate uptake. Anaerobic P release rate increased with an increase in pH. Moreover, when pH exceeded a relatively high value of 8.0, the dissolved P concentration decreased in the liquid phase, because of chemical precipitation. This observation suggested that pH should be strictly controlled below 8.0 to avoid chemical precipitation if the biological denitrifying phosphorus removal capability is to be studied accurately.     

2016年12月江苏省两次连续污染过程气象条件对比分析

利用地面常规气象观测资料、NCEP（National Centers for Environmental Prediction）再分析资料、AQI（空气质量指数）、ρ（PM_2.5）、ρ（PM₁₀）等大气环境监测数据,对2016年12月江苏省连续出现的两次大范围大气污染过程进行了对比分析.结果表明:这两次连续污染天气过程可分为颗粒物积聚-清除-再积聚-彻底清除4个阶段,相应地,地面形势表现为均压场-低压倒槽-西路冷空气-东路冷空气.第1次污染天气形成和维持主要是长时间受均压场控制、近地层逆温和高相对湿度有利于颗粒物积聚;第2次污染天气形成和维持主要是因西路冷空气南下、上游重污染地区颗粒物随冷空气向江苏省输送.持续降水和持续2.0 m/s以上偏东风对大气中颗粒物有较明显的清除作用.淮北西部垂直、水平扩散条件差、降水清除时间短,导致该地区在全省污染等级最严重、持续时间最长.西路冷空气影响期间,各站颗粒物质量浓度转为快速上升,东部地区在偏西风持续49~58 h后空气质量改善为良,中西部地区无法得到有效改善;东路冷空气影响7~22 h后,中西部地区空气质量转为良,高压底部持续偏东风使全省颗粒物得到彻底清除,连续污染天气结束.研究显示,西路弱冷空气的输送会加剧江苏省的污染程度,持续较长时间的东路冷空气则可以改善江苏省的空气质量.      

危险废物填埋场环境风险控制的地质实践

危险废物填埋场工程的经验之一是选址颇费周折,周期长。对环境地质条件的理解与重视不够,以及利用不当,常常会造成选址失误以至失败。在扬州危险废物填埋场选址中,应用环境地质条件级序论证的办法,将场址选在一个比较完整、稳定的上升型断块内,处于独立水文地质单元内,并择定巨厚隔水泥质砂岩为填埋库基础。由于充分利用和发挥了场地环境地质条件的优越性,大大降低了危废填埋场的环境风险,奠定了设计战略性危废填埋大库的基础。环境地质条件优越的危废填埋场场址本身日益稀缺而逐渐资源化。     

2007年环胶州湾入海河流污染状况和污染物入海通量分析

根据2007年入胶州湾的7条主要河流入海断面水体污染物调查资料,分析了各条河流的水质状况,并计算了COD、氨氮、总磷和油类等污染物的入海通量。结果表明,7条河流入海断面的水质均属于劣V类,而丰水期水质较好,枯水期和平水期水质相对较差;各河流的首要污染物不同,其中,板桥坊河为COD,海泊河、李村河与楼山河为氨氮,墨水河与镰湾河为油类,大沽河为总磷。从入海通量来看,大沽河、海泊河和墨水河的COD排海通量较大,约占7条河流排海总量70％左右;李村河、海泊河与墨水河的氨氮排海通量较大,约占7条河流排海总量的70％以上,对于总磷,大沽河排放量最大,约占7条河流排海总量的70％以上,对于油类,墨水河、李村河与大沽河排放量较大,占7务河流排海总量的70％以上。最后在分析各河流污染物来源的基础上,初步提出了防治水污染的相应对策和建议。     

论黑龙江省发展有机农业基础条件及优势

黑龙江省是全球三大黑土地之一,富饶美丽的黑土地是发展有机农业最好的地方。文章分析了黑龙江省发展有机农业的优势和基础条件,划分了各类种植区域,探讨了有机农业发展方向,为黑龙江省发展有机农业提供了参考依据。     

淮北地区矽卡岩型铁铜矿床控矿条件分析与成矿模式

淮北地区位于安徽省北部,是重要金属成矿区之一.地质构造单元归属华北陆块,其矽卡岩型矿床的控矿条件和成矿模式既与华北地区邯邢式接触交代型铁矿床相似而又有区别.邯邢式铁矿主要围岩地层为奥陶系,矿石成分简单,以磁铁矿为主.淮北地区部分矿床具有这一特征,而另一部分矿床的特征与此有较大差异:围岩地层为寒武系,矿石成分复杂,以铁铜矿为主,并含有金、钼等其它有益元素,岩体分叉侵入,多层成矿,矿体产于燕山中期石英二长闪长玢岩与寒武系中上统内接触带及正接触带,镁质矽卡岩较发育,含铜矽卡岩可见于外接触带.为了与邯邢式铁矿区别,称其为前常式铁铜矿.本区矽卡岩型矿床的赋矿层位为中上寒武统-下奥陶统.其中,寒武系铁矿比例43.39%、铜矿比例92.67%、金矿比例100%,奥陶系铁矿比例56.61%、铜矿比例7.33%.本文在介绍地质背景的基础上、较系统地分析了控矿条件和成矿模式,提出了岩浆侵入活动中心(或活动带)与寒武系接触带为重点找矿方向的观点,并明确指出远离侵入中心(带)的岩床,其成矿性差.文中还介绍了覆盖区识别岩浆侵入活动中心(或活动带)的方法.     

上城区生活居住环境满意率普遍调查的统计分析

2009年,杭州市上城区统计局民生民意调查中心在全区6个街道开展了市民普遍调查,调查针对市民警遗关心的五项民生内容（计生、安全生产、城市综合治理、居家养老服务、生活居住环境）展开。这份调查材料基本反映了上城区居民群众对民生关注内容的满意程度。文章重点对生活居住环境满意率这一指标进行统计分析。     

Numerical estimation of photovoltaic–electrolyzer system performance on the basis of a weather database

We performed a numerical simulation to investigate the performance of a photovoltaic (PV)–electrolyzer on the basis of a simulated weather database during the summer solstice (SS), autumnal equinox (AE), and winter solstice (WS), and all year round. First, we selected a location in southern Taiwan (latitude: 22.65°N) to create a local weather simulation database that included daily solar radiation, wind speed, and ambient temperature. The I–V curves of a PV system and an electrolyzer were obtained numerically by using Simpson integration computation. Subsequently, the optimal configuration of a PV driving system comprising the electrolyzer and the PV panel was determined. The database of weather conditions was input into the numerical estimation model of the PV–electrolyzer system, and the hydrogen generation rates and hydrogen production volumes under both clear skies and changeable weather conditions were obtained.     

不同保存条件下水样主要污染因子衰减趋势的研究

水样由于成分不同,在不同保存条件下不同的污染因子的衰减不同。通过实验研究了地表水、生活污水、化工废水等多种不同废水、不同浓度水样,在不同保存条件下化学需氧量、氨氮等主要污染因子的衰减趋势。研究结果表明,高锰酸盐指数以及重金属如铜、镍和铬在水样中的衰减受固定剂和温度的影响较大,而容器类型对其影响较小;不同类型废水中的化学需氧量衰减趋势差异较大,其中化工废水中化学需氧量的衰减率最高,而纺织废水和线路板废水较小。氨氮和总磷的衰减受微生物影响较大,其中氨氮主要是受硝化和反硝化反应的影响。