水平潜流人工湿地脱氮性能研究

试验研究了植物、季节变化对水平潜流人工湿地脱氮性能的影响及湿地去除污染物的沿程趋势.结果表明,潜流湿地脱氮、降解有机物性能与植物生长、季节变化密切相关,相关程度为脱氮大于降解有机物.潜流湿地降解有机物的主要场所位于湿地前、中部.湿地对COD的去除率在46.43%～90.85%间变化.潜流湿地对有机物降解、硝化与反硝化反应具有沿程同步性.种植芦苇的潜流人工湿地的TN去除率可以达到94.57%,芦苇湿地的脱氮性能明显好于空白湿地.潜流人工湿地具有良好的降解有机物和脱氮性能.     

人工湿地污水处理系统脱氮研究进展

系统地介绍了人工湿地去除污水中氮污染物的机理及国内外研究进展，详细阐述了影响人工湿地污水处理系统脱氮的内、外界因素，对于人工湿地污水处理工艺的推广应用提供科学依据。     

分子筛催化剂生产废水的生物处理

采用氨化—硝化—反硝化三段联合生物工艺处理分子筛催化剂生产过程中产生的含有机胺废水。实验结果表明：在氨化过程中,当进水COD稳定为1 200~1 600 mg/L时,出水COD低于300 mg/L,COD去除率稳定在80%左右,当进水ρ（有机氮）为100~160 mg/L时,出水ρ（有机氮）均低于30 mg/L,有机氮去除率大于80%,在整个氨化过程中,出水ρ（氨氮）较进水ρ（氨氮）提高了35~200 mg/L;硝化过程中,当进水ρ（氨氮）小于等于300 mg/L时,出水ρ（氨氮）最终稳定在15 mg/L以内,氨氮去除率大于90%;在反硝化过程中,亚硝酸盐氮去除率基本稳定在98%以上,最终出水COD低于80 mg/L,出水ρ（总氮）低于25 mg/L。     

Cr（Ⅵ）对活性污泥系统反硝化过程的影响

采用反硝化反应器,研究了Cr（Ⅵ）对活性污泥系统反硝化过程的影响。在进水Cr（Ⅵ）投加量2.5 mg/L条件下,活性污泥反硝化过程中COD和硝酸盐氮的去除率受到的影响较小,而在10.0 mg/L条件下受到的影响较大,COD和硝酸盐氮的去除率分别从最初的97.1%和99.0%降至70.6%和24.7%。在停止投加Cr（Ⅵ）后的恢复期内,反硝化系统可以逐渐恢复对COD和硝酸盐氮的去除,亚硝酸盐氮仍会有积累,但随着时间的延长可恢复至初始状态。硝酸盐氮还原为亚硝酸盐氮的过程比亚硝酸盐氮的还原过程更易受到Cr（Ⅵ）的影响。     

Cr(Ⅵ)对活性污泥系统反硝化过程的影响

采用反硝化反应器,研究了Cr(Ⅵ)对活性污泥系统反硝化过程的影响。在进水Cr(Ⅵ)投加量2.5 mg/L条件下,活性污泥反硝化过程中COD和硝酸盐氮的去除率受到的影响较小,而在10.0 mg/L条件下受到的影响较大,COD和硝酸盐氮的去除率分别从最初的97.1%和99.0%降至70.6%和24.7%。在停止投加Cr(Ⅵ)后的恢复期内,反硝化系统可以逐渐恢复对COD和硝酸盐氮的去除,亚硝酸盐氮仍会有积累,但随着时间的延长可恢复至初始状态。硝酸盐氮还原为亚硝酸盐氮的过程比亚硝酸盐氮的还原过程更易受到Cr(Ⅵ)的影响。     

C/N及氮源形式对潜流式人工湿地脱氮效果的影响

研究了C/N及氮源形式对潜流式人工湿地脱氮效果的影响.结果表明,当潜流式人工湿地进水C/N由2.0增大到6.0时,总氮的去除效率由45%提高到70%;而当进水C/N由6.0增大到14.0时,总氮的去除效率仅由70%提高到85%,提高的幅度相对较小.潜流式人工湿地对总氮的去除效率随NH 4 -N/TN的增加而降低,随着NO-3 -N/TN的增加而提高.     

悬浮滤料在上向流反硝化滤池中试装置中的应用

以聚苯乙烯泡沫滤珠作为上向流反硝化滤池的滤料,在中试装置中考察了此种悬浮滤料的脱氮效果及其过滤功能.试验结果表明:在进水流量为13.5 m3/h的情况下,随着碳氮质量比(碳氮比)的升高,NO3--N去除率逐渐提高,出水COD也逐渐提高,适宜的碳氮比为5,此条件下出水COD小于50 mg/L;水力停留时间(HRT)越长,...     

氨氮废水生物脱氮研究进展

与传统的硝化-反硝化氨氮废水脱氮方法相比,短程硝化-反硝化和同时硝化-反硝化都是近年来研究开发的新型生物脱氮工艺,具有能耗低、运行时间短、氮去除效率高等特点.结合国内外废水生物脱氮的研究现状,系统综述了短程硝化-反硝化和同时硝化-反硝化两种新工艺的研究进展, 并深入讨论了短程硝化-反硝化中亚硝酸盐累积问题.     

基于固态碳源的自养-异养耦合生物脱氮工艺研究

采用基于固态碳源的厌氧氨氧化与反硝化耦合脱氮工艺处理高氮低碳的金属热处理废水。通过接种城市生活污水处理厂剩余污泥和厌氧氨氧化絮状污泥,研究了以固态碳源（3-羟基丁酸脂和3-羟基戊酸脂共聚物,PHBV）和沸石为组合填料的分区式耦合反应器的启动和运行特性。经过76 d的运行,耦合反应器的总氮去除速率达1.05 kg/（m³·d）,且具有良好的出水COD稳定性。废水经过反应器沸石区后,氨氮去除率达97%,亚硝态氮去除率达81%,而硝态氮去除率几乎为零;经过PHBV区后,硝态氮去除率达76%,亚硝态氮去除率达99%,氨氮去除率达97%。沸石区主要进行厌氧氨氧化反应,PHBV区主要进行反硝化反应,功能分区明确,耦合效果较好。     

制药废水硝化-反硝化除氮研究

含高浓度氮的制药废水经好氧生化处理后,虽然出水的ＣＯＤ,ＢＯＤ５均可达到行业排放标准,但ＴＮ仍高达约１７０ｍｇ／Ｌ。本研究在曝气池中设置填料,利用生物膜外层好氧,内层缺氧厌氧的条件,使硝化－反硝化脱氮在同一构筑物内进行,ＮＨ３－Ｎ和ＴＮ去除率分别可达约９０％和７０％。在本试验条件范围内,温度越高,负荷越低,硝化和反硝化作用越完全,ＮＨ３－Ｎ和ＴＮ去除率越高。     

Combinations of Horizontal and Vertical Flow Constructed Wetlands to Improve Nitrogen Removal

Nitrogen removal in wetlands is achieved through two pathways: (a) N cycling and (b) storage. N cycling is a permanent removal pathway. There has been an increasing interest in the development of technologies to alleviate permanent nitrogen removal limitation in constructed wetlands by ensuring prevalence of conditions enhancing N cycling. The purpose of this study is to review an emerging technology of vegetated submerged bed constructed wetland system aimed at improving nitrogen removal in wetlands through rational system design. The design and performance of this system type is evaluated. The oxygen transfer capacity and nitrogen removal mechanisms on system performance are evaluated. Constructed wetland combinations most commonly consist of vertical flow (VF) and horizontal flow (HF) beds where VF and HF are aimed at nitrification and denitrification, respectively. Nitrate nitrogen accumulation is the most limiting factor in typical VF based systems.     

Comparison of five organic wastes regarding their behaviour during composting: Part 2, nitrogen dynamic

This paper aimed to compare household waste, separated pig solids, food waste, pig slaughterhouse sludge and green algae regarding processes ruling nitrogen dynamic during composting. For each waste, three composting simulations were performed in parallel in three similar reactors (300 L), each one under a constant aeration rate. The aeration flows applied were comprised between 100 and 1100 L/h. The initial waste and the compost were characterized through the measurements of their contents in dry matter, total carbon, Kjeldahl and total ammoniacal nitrogen, nitrite and nitrate. Kjeldahl and total ammoniacal nitrogen and nitrite and nitrate were measured in leachates and in condensates too. Ammonia and nitrous oxide emissions were monitored in continue. The cumulated emissions in ammonia and in nitrous oxide were given for each waste and at each aeration rate. The paper focused on process of ammonification and on transformations and transfer of total ammoniacal nitrogen. The parameters of nitrous oxide emissions were not investigated. The removal rate of total Kjeldahl nitrogen was shown being closely tied to the ammonification rate. Ammonification was modelled thanks to the calculation of the ratio of biodegradable carbon to organic nitrogen content of the biodegradable fraction. The wastes were shown to differ significantly regarding their ammonification ability. Nitrogen balances were calculated by subtracting nitrogen losses from nitrogen removed from material. Defaults in nitrogen balances were assumed to correspond to conversion of nitrate even nitrite into molecular nitrogen and then to the previous conversion by nitrification of total ammoniacal nitrogen. The pool of total ammoniacal nitrogen, i.e. total ammoniacal nitrogen initially contained in waste plus total ammoniacal nitrogen released by ammonification, was calculated for each experiment. Then, this pool was used as the referring amount in the calculation of the rates of accumulation, stripping and nitrification of total ammoniacal nitrogen. Separated pig solids were characterised by a high ability to accumulate total ammoniacal nitrogen. Whatever the waste, the striping rate depended mostly on the aeration rate and on the pool concentration in biofilm. The nitrification rate was observed as all the higher as the concentration in total ammoniacal nitrogen in the initial waste was low. Thus, household waste and green algae exhibited the highest nitrification rates. This result could mean that in case of low concentrations in total ammoniacal nitrogen, a nitrifying biomass was already developed and that this biomass consumed it. In contrast, in case of high concentrations, this could traduce some difficulties for nitrifying microorganisms to develop.     

硫酸盐对微生物燃料电池脱氮的影响

构建了双室型微生物燃料电池(MFC),探讨了硫酸盐对MFC阴极脱氮效果和产电性能的影响。实验结果表明:缺氧阴极室中,硝酸盐氮、硫酸盐的还原存在一定的竞争关系,且硫酸盐对电子的竞争能力比硝酸盐氮强;当S与N的质量比(记为S/N)为2∶1时,72 h后的硫酸根去除率达96.41%,而硝酸盐氮去除率仅为36.86%;在S/N为2∶1的条件下,当电压达307.6 m V时,功率密度达最大值15.77 W/m2,电池内阻为100Ω,与未加入硫酸盐时相比产电性能明显提高。     

Organic and nitrogen removal from landfill leachate in aerobic granular sludge sequencing batch reactors

Granule sequencing batch reactors (GSBR) were established for landfill leachate treatment, and the COD removal was analyzed kinetically using a modified model. Results showed that COD removal rate decreased as influent ammonium concentration increasing. Characteristics of nitrogen removal at different influent ammonium levels were also studied. When the ammonium concentration in the landfill leachate was 366 mg L⁻¹, the dominant nitrogen removal process in the GSBR was simultaneous nitrification and denitrification (SND). Under the ammonium concentration of 788 mg L⁻¹, nitrite accumulation occurred and the accumulated nitrite was reduced to nitrogen gas by the shortcut denitrification process. When the influent ammonium increased to a higher level of 1105 mg L⁻¹, accumulation of nitrite and nitrate lasted in the whole cycle, and the removal efficiencies of total nitrogen and ammonium decreased to only 35.0% and 39.3%, respectively. Results also showed that DO was a useful process controlling parameter for the organics and nitrogen removal at low ammonium input.     

Landfill leachate treatment using sub-surface flow constructed wetland by Cyperus haspan

Performance evaluation of pilot scale sub-surface constructed wetlands was carried out in treating leachate from Pulau Burung Sanitary Landfill (PBSL). The constructed wetland was planted with Cyperus haspan with sand and gravel used as substrate media. The experiment was operated for three weeks retention time and during the experimentation, the influent and effluent samples were tested for its pH, turbidity, color, total suspended solid (TSS), chemical oxygen demand (COD), biochemical oxygen demand (BOD(5)), ammonia nitrogen (NH(3)-N), Total phosphorus (TP), total nitrogen (TN) and also for heavy metals such as iron (Fe), magnesium (Mg), manganese (Mn) and zinc (Zn) concentrations. The results showed that the constructed wetlands with C. haspan were capable of removing 7.2-12.4% of pH, 39.3-86.6% of turbidity, 63.5-86.6% of color, 59.7-98.8% of TSS, 39.2-91.8% of COD, 60.8-78.7% of BOD(5), 29.8-53.8% of NH(3)-N, 59.8-99.7% of TP, 33.8-67.0% of TN, 34.9-59.0% of Fe, 29.0-75.0% of Mg, 51.2-70.5% of Mn, and 75.9-89.4% of Zn. The significance of removal was manifested in the quality of the effluent obtained at the end of the study. High removal efficiencies in the study proved that leachate could be treated effectively using subsurface constructed wetlands with C. haspan plant.     

In situ ammonia removal in bioreactor landfill leachate

Although bioreactor landfills have many advantages associated with them, challenges remain, including the persistence of NH(3)-N in the leachate. Because NH(3)-N is both persistent and toxic, it will likely influence when the landfill is biologically stable and when post-closure monitoring may end. An in situ nitrogen removal technique would be advantageous. Recent studies have shown the efficacy of such processes; however, they are lacking the data required to enable adequate implementation at field-scale bioreactor landfills. Research was conducted to evaluate the kinetics of in situ ammonia removal in both acclimated and unacclimated wastes to aid in developing guidance for field-scale implementation. Results demonstrate that in situ nitrification is feasible in an aerated solid waste environment and that the potential for simultaneous nitrification and denitrification (even under low biodegradable C:N conditions) in field-scale bioreactor landfills is significant due to the presence of both aerobic and anoxic areas. All rate data fit well to Monod kinetics, with specific rates of removal of 0.196 and 0.117 mgN/day-g dry waste and half-saturation constants of 59.6 and 147 mgN/L for acclimated and unacclimated wastes, respectively. Although specific rates of ammonia removal in the unacclimated waste are lower than in the acclimated waste, a relatively quick start-up of ammonia removal was observed in the unacclimated waste. Using the removal rate expressions developed will allow for estimation of the treatment times and volumes necessary to remove NH(3)-N from recirculated landfill leachate.     

均匀流场水平潜流人工湿地对四环素类抗生素的去除效果

利用均匀流场水平潜流人工湿地实验系统处理含四环素类抗生素废水,考察了湿地系统对抗生素的去除率、出水口差向代谢产物的含量以及抗生素在湿地植物中的累积情况。实验结果表明:在水力停留时间为2 d、土霉素、四环素、金霉素和强力霉素进水质量浓度均为200 μg/L时,出水中上述4种抗生素的平均去除率分别为98.62%、93.06%、99.13%和92.25%;出水可检出3种四环素类抗生素代谢产物,分别为差向土霉素、差向金霉素和差向四环素,质量浓度分别为(3.69±0.23) μg/L、(13.81±0.47) μg/L和(19.00±0.63) μg/L;湿地植物美人蕉的根、茎、叶中可以检测到土霉素和四环素,四环素含量的大小顺序为茎>根>叶。     

气升式环流生物反应器处理废水厌氧过程研究

采用气升式环流生物反应器处理模拟废水。周期性通入空气和氮气来实现厌氧一好氧交替过程。对厌氧一好氧过程和普通好氧过程进行了对比,研究了厌氧处理时间和曝气速率对生物除磷效果的影响。结果表明,厌氧过程可以显著地增强生物除磷效果,与普通好氧过程相比,在进水总磷质量浓度为10mg／L时,磷的去除率可以提高30％,而COD的去除基本不受影响;适当延长厌氧处理时间和适当增大厌氧过程曝气速率可以改善厌氧环境及活性污泥性能,提高磷的去除率。