炼油污水深度处理回用的中试

采用两级曝气生物滤池和多介质滤池相串联的中试装置,连续处理某炼油厂污水车间二浮出水,主要考察了中试装置对污水中主要污染物的去除效果和规律,并确定了适宜的气水比。试验结果表明:采用该工艺时,除石油类外,其它各项指标都达到《循环冷却水用再生水水质标准》(HG/T3923-2007)要求的水质指标;两级曝气生物滤池的气水比分别选用5.6∶1和5∶1为宜;验证了BAF是通过生物氧化和过滤两种作用来去除COD,第一段BAF以去除污水中碳化有机物为主,第二段BAF主要以去除污水中的NH4+-N为主。     

吉林省松花江中下游污染物排放总量控制

分析了实施总量控制的理论依据 ;并以此研究吉林省松花江中下游污染物总量控制以及吉林市控制单元的总量控制方案 ;最后探讨了总量控制措施。     

硝酸盐氮,亚硝酸盐氮总量紫外吸收快速测定

水体中尤其是海水中硝酸盐氮的测定较繁琐,干扰物质多,分析时间长,重现性差,准确性不高。文章通过实验介绍一种省时、省力、简便可行不消耗化学试剂且抗氯化物干扰、精度和准确度较高的硝酸盐氮、亚硝酸盐氮总量测定方法。     

我国耕地管制的必要性及当前任务

本文针对我国耕地资源人均数量少、质量低的特点,提出在我国实现耕地管制的必要性,进而提出当前我国耕地管制的主要任务。     

三峡库区腹心地带消落区土壤氮磷含量调查

消落区土壤中氮磷是上覆水体营养物质的潜在来源之一。在2008年底三峡蓄水至172 m之前,采样分析了小江（澎溪河）等库区5条典型支流淹没前的消落区土壤氮磷含量分布情况。在研究样区范围内,消落区土壤全氮均值为1317±0484 mg/g,变化范围在0459~2735 mg/g,而土壤全磷均值为0676±0282 mg/g,变化范围在0314~2799 mg/g。不同的土地利用方式消落区土壤全氮含量有明显差异,耕地消落区和园林地消落区的全氮值明显高于河滩地消落区。不同流域之间氮素差异也达到极显著水平,朱衣河和大宁河流域消落区土壤氮素要明显高于其他3条支流。但是,不同土地利用方式的消落区之间全磷差异不显著,不同流域之间磷素差异也不显著。相比长江中下游一些浅水湖泊的底泥,库区消落区土壤中全氮和全磷含量水平已处于偏高状态,向上覆水体释放的风险较大。小江流域的丰乐镇和养鹿镇、朱衣河的胡家坝地区是研究范围内释放风险高的区域.     

负荷历时曲线法在梁子湖流域污染容量总量控制中的应用

采用负荷历时曲线法(LDC),基于水质保护目标,研究水体纳污能力,确定最大日负荷总量(TMDL)是当前流域污染总量控制的主要方法之一。根据梁子湖高桥河流域控制断面2008~2011年的水文、水质数据,以主要污染物COD为指标,将负荷历史曲线法运用到梁子湖高桥河等子流域污染容量总量控制中,对该流域的最大日负荷(TMDL)变化规律进行分析,提出流域不同水文条件下的污染负荷消减量。研究结果表明:梁子湖水环境受面源污染影响较大。高桥河、徐家港、张家桥港、山坡港、宁港流域,在高流量期实际负荷值均已超出了允许负荷,其削减量分别为61.36、4.33、12.98、3.84、7.13 t/d;徐家港和宁港流域在丰水期实际负荷值也超出了允许负荷,削减量分别为0.16、0.17 t/d。该研究为流域相关管理部门对湖泊水环境的污染控制提供可靠的决策依据。     

Start-up performances of dry anaerobic mesophilic and thermophilic digestions of organic solid wastes

Two dry anaerobic digestions of organic solid wastes were conducted for 6 weeks in a lab-scale batch experiment for investigating the start-up performances under mesophilic and thermophilic conditions. The enzymatic activities, i.e., β-glucosidase, N-α-benzoyl-Largininamide （BAA）-hydrolysing protease, urease and phosphatase activities were analysed. The BAA-hydrolysing protease activity during the first 2-3 weeks was low with low pH, but was enhanced later with the pH increase. β-Glucosidase activity showed the lowest values in weeks 1-2, and recovered with the increase of BAA-hydrolysing protease activity. Acetic acid dominated most of the total VFAs in thermophilic digestion, while propionate and butyrate dominated in mesophilic digestion. Thermophilic digestion was confirmed more feasible for achieving better performance against misbalance, especially during the start-up period in a dry anaerobic digestion process.     

Vertical distribution of nonylphenol and nonylphenol ethoxylates in sedimentary core from the Beipaiming Channel, North China

The vertical profiles of nonylphenol （NP） and nonylphenol ethoxylates （NPEOs） were investigated in a sediment core from the Beipaiming Channel, North China using high sensitive LC-MS and GC-MS metthods In this core, relatively high concentrations of NP and NPEOs occurred in the surface sediment （≤40 cm）, with the maximum value of NP and NPEOs reaching 3539 and 12735 mg/g, respectively, whereas, no NP or NPEOs were detected in deeper sediments （〉40 cm）. The high concentrations of NP and NPEOs in the surface layers suggested recent inputs in this area. NPEOs with short ethoxy chains （NPnEO, n=0-3） were dominant in the NPEO mixture with percentages from 54% to 78%, which were similar to the distribution of homolog NPEO in effluents from nearby sewage treatment plants （STPs）, indicating that the channel received the effluents from these STPs. The sewage treatment ratio was quite similar to that found in North America before the 1980s. Finally, the concentrations of NP and NPEOs were related to the total organic carbon （TOC） （p〈0.001）, suggesting that TOC was an important factor for vertical distribution of NPEOs and NP from the Beipaiming Channel.     

Nitrogen interception in floodwater of rice field in Taihu region of China

A field experiment located in Taihu Lake Basin of China was conducted,by application of urea or a mixture of urea with manure, to elucidate the interception of nitrogen(N)export in a typical rice field through"zero-drainage water management"combined with sound irrigation,rainfall forecasting and field drying,N concentrations in floodwater rapidly declined before the first event of field drying after three split fertilizations,and subsequently tended to retum to the background level.Before the first field drying,total particulate nitrogen(TPN)was the predominant N form in floodwater of plots with no N input,dissolved inorganic nitrogen(DIN)on plots that received urea only,and dissolved organic nitrogen(DON)on plots treated with the mixture of urea and manure.Thereafter TPN became the major form.No N export was found from the rice field,but total nitrogen(TN)of 15.8 kg/hm~2 was remained,mainly due to soil N sorption.The results recommended the zero-drainage water management for full-scale areas for minimizing N export.     

Treatment of tannery wastewater by electrocoagulation

Treatment of tannery wastewater by electrocoagulation with low cell current(≤1A)and soluble electrodes(mild steel electrodes and aluminum electrodes)was studied.Compared with aluminum electrodes,mild steel electrodes were more effective for the removal of sulfide,with a removal efficiency of over 90%.But during the treatment process,black color precipitate typical to iron(Ⅱ)sulfides was produced.While aluminum electrodes were effective to eliminate the colority of the effluent,the removal efficiency of sulfide was lower than 12%.The mechanisms of the removal of chemical oxygen demand,ammonia,total organic carbon,sulfide and colority with the two soluble electrodes(mild steel and aluminum electrodes)were discussed in detail.In order to exert the predominance of diffenent types of electrodes,the tannery wastewater was treated using mild steel electrodes first followed by the filter and finally by the aluminum electrodes,the elimination rates of chemical oxygen demand,ammonia,total organic carbon,sulfide and colority were 68.0%,43.1%,55.1%,96.7% and 84.3%,respectively,with the initial concentrations 2413.1 mg/L,223.4 mg/L,1000.4 mg/L,112.3 mg/L and 256 dilution times,respectively.The absorbance spectra and energy consumption during electrocoagulation process were also discussed.