聚丙烯酰胺降解的研究进展

聚丙烯酰胺(PAM)的降解一直是人们研究的重点。文章综述了PAM的主要降解方式,包括化学降解、热降解、机械降解和生物降解,分析了PAM各种降解的可行性及降解产物,并探讨了丙烯酰胺在环境中的降解情况,为以后PAM的扩大应用及其污染治理提供了充分的参考和依据。     

应用聚丙烯酰胺的环境与生态行为研究

聚丙烯酰胺(PAM)在油田中的大量使用,其环境和生态行为及降解产物对环境的潜在危害,都亟待去研究。本文分析论述了其物理、化学性质及化学降解、机械降解、热降解、生物降解性,及影响其在土壤中的被吸附的因素和生态毒理学研究,提出有待进一步研究的课题为:PAM在油藏条件下的降解机理和降解速度;PAM及其衍生物在环境中的存在形式及其迁移转化的方式,在生物体内的存在形式及其在生物圈内的迁移转化等。     

无机-有机高分子复合絮凝剂处理含油废水的试验研究

研究了用聚合氯化铝（PAC）、聚合硫酸铁（PFS）、聚丙烯酰胺（PAM）及改性蒙托石等不同无机—有机高分子絮凝剂复配使用处理炼钢厂连铸含油废水的除油效果,考察了不同絮凝剂的复配以及絮凝剂的不同复配比例对处理效果的影响。试验结果表明,用聚合氯化铝（PAC）＋聚合硫酸铁（PFS）＋聚丙烯酰胺（PAM）3种絮凝剂复配使用除油效果最佳,当3种絮凝剂的复配比为2∶2∶3时除油效果最好,除油率达到88.2%,达到国家排放标准。     

聚丙烯酰胺降解菌的分离和鉴定

三次采油产生的大量含聚丙烯酰胺(PAM)的污水急需处理,其核心问题是PAM的生物化学降解。文章叙述了从含聚合物油田污水中分离到七株PAM降解菌的过程,并对其营养物体系进行了初步研究及分子生物学鉴定。结果表明,分离到的七株菌可以以PAM为唯一氮源和碳源进行生长,但是生长速度较慢,添加液蜡或酵母膏等可导致微生物菌群的共代谢,能加快PAM的生物降解。七株菌分别归类于放线杆菌纲和α-变形菌纲及芽孢杆菌,与数据库中已知菌的同源性均超过98%。     

回收与降解聚驱采出水的工艺探讨

含聚污水的处理是困扰石油行业的难题之一。基于聚驱采出水的特点,围绕聚合物的回收利用和降解理论及技术,探讨国内外含聚污水处理技术的研究与应用现状,对比分析现有处理技术存在的问题及适应性,提出采用化学混凝、气浮和水质改性等技术来回收利用PAM(聚丙烯酰胺)的新思路,打破了降解PAM的传统思维,同时分析含聚污水处理与利用技术的可行性与应用前景,有望实现含聚污水的循环利用。     

反相乳液聚合制备阳离子聚丙烯酰胺及其絮凝性能评价

研究了单体浓度、单体配比、反应温度、引发剂用量等因素对所制备的阳离子聚丙烯酰胺特性粘度、转化率、阳离子度的影响,并对产品的污水絮凝性能进行了评价。较佳的制备条件为:单体浓度为45%,单体配比为7∶3,引发剂用量m(引发剂)/m(单体)为0.5%,引发温度为45℃。用红外光谱对共聚物进行了结构表征,结果表明聚合物中有六元氮杂环的存在,达到预定要求。对共聚物进行了油田污水絮凝性能评价,研究表明单独使用自制阳离子聚丙烯酰胺(CPAM)时浊度的去除率为86.22%,COD去除率为87.95%,与聚合氯化铝复配使用时浊度去除率提高到92.91%,COD去除率提高到92.68%。     

石油降解菌的分离筛选及混合菌群的构建与优化

以河南濮阳油田超重质原油为研究对象,从污染井场土壤中分离并筛选出几株高效降解细菌、酵母菌和霉菌。由于不同类型微生物对碳源的利用目标和方式有所不同,而将3类不同类型菌种进行排列组合进行降解实验,最终优选出一组石油降解优势菌群。该文还利用正交优化法对降解菌的最佳添加量进行计算,结果显示,最佳接种量为X25：1．5％,Z3：1％,X18：1％,Z28：2％。利用该优化结果进行降解实验,石油的降解率在一定程度上提高了。在对濮阳、南阳和延长油田不同原油进行为期8d的降解实验中,显示了较高的降解效率,降解率分别为56．93％、65．66％、82．69％。实验证明,该降解菌群能不仅能有效够降解超重油,而且对重质原油和轻质原油表现出更好的降解能力。因此,该研究为石油污染物的降解提供了有效的菌种资源。     

聚丙烯酰胺化学降解技术研究进展

聚丙烯酰胺化学降解技术是目前油田含聚污水处理的重要技术之一,包括氧化降解法、光降解法和光催化降解法。文章介绍了此项技术在降解机理和应用方面的研究进展,并通过实验证明了聚丙烯酰胺氧化降解和光降解的可行性,对油田污水中聚丙烯酰胺的化学降解处理具有一定的指导意义。     

一种高效复合絮凝剂对多种废水的处理效果

用聚合氯化铝（PAC）和聚丙烯酰胺（PAM）复配成复合絮凝剂（PAC＋PAM）应用于污染河水、生活污水、工业废水和餐饮废水等6种废水的处理，结果表明。PAC、PAM、PAC＋PAM对污染河水的CODc。SS、浊度有显著降低作用，PAC＋PAM的净水效果明显优于PAC和PAM；PAC＋PAM对6种废水中COD的去除率为81．5％～90．4％，平均84．6％。对SS的去除率为81．9％～96．5％，平均88．9％，对浊度的去除率为91．3％-98．0％，平均95．1％；处理后悬浮物基本被絮凝沉降，水体变得较清澈透明，异味或臭味消除。说明本PAC＋PAM复合絮凝剂对各种废水均有良好的净水效果，具有重要的应用价值。     

PAM投加量对臭氧氧化厌氧消化耦合工艺污泥脱水性的影响

提高污泥的脱水性是降低污泥处理难度的必要前提.本文以传统厌氧消化工艺为参照,研究臭氧氧化厌氧消化耦合工艺对化学一级强化污泥脱水挂的影响,以及PAM投加量对厌氧消化污泥脱水性的影响.结果表明,与浓缩污泥相比,传统厌氧消化后污泥脱水性下降了11.8％,而臭氧氧化厌氧消化耦合工艺中污泥没有变化;随着PAM投加量的增加,污泥的脱水性能显著提高;当PAM梗加量为2.0 mg/g DS时,臭氧氧化厌氧消化耦合工艺中污泥的脱水性能达到最佳状态,而当PAM投加量为2.5 mg/g DS时,厌氧消化工艺中污泥的脱水性能才达到最佳状态.     

Controlling tailwater sediment and phosphorus concentrations with polyacrylamide in the Imperial Valley, California

External loading of phosphorus (P) from agricultural surface discharge (tailwater) is the main cause of excessive algae growth and the eutrophication of the Salton Sea, California. Continuous polyacrylamide (PAM) applications to agricultural irrigation water inflows were evaluated as a means of reducing sediment and P in tailwater. Zero (control) and 1 mg L(-1) PAM (PAM1) treatments were compared at 17 Imperial Valley field sites. Five and 10 mg L(-1) PAM treatments (PAM5, PAM10) were conducted at one site. The particulate phosphorus (Pp) fraction was determined as the difference between total phosphorus (Pt) and the soluble phosphorus (Ps) fraction. We observed 73, 82, and 98% turbidity reduction with PAM1, PAM5, and PAM10 treatments. Although eight field sites had control tailwater sediment concentrations above the New River total maximum daily loads (TMDL), all but one were made compliant during their paired PAM1 treatments. While PAM1 and PAM10 reduced tail water Pp by 31 and 78%, none of the treatments tested reduced Ps. This may have been caused by high irrigation water Na concentrations which would reduce Ca adsorption and Ca-phosphate bridging on the PAM. The PAM1 treatments resulted in <0.5 mg L(-1) drain water polyacrylamide concentrations 1.6 km downstream of PAM addition, while PAM5 and PAM10 treatments produced > 2 mg L(-1) drain water polyacrylamide concentrations. We concluded that, although PAM practically eliminates Imperial Valley tailwater sediment loads, it does not effectively reduce tailwater Ps, the P fraction most responsible for the eutrophication of the Salton Sea.     

油污土壤微生物生态研究

利用微生物降解土壤中的油等有机污染物的就地生物治理技术受土壤及环境的诸多条件影响,在使用该技术之前,首先要进行油污土壤微生物生态研究,弄清影响微生物处理效果的各种因素。通过对胜利油田油污土壤微生物研究得知：胜利油田油污土壤的ｐＨ值、含水量等指标利于微生物降解原油。土壤优势菌种多为原油降解菌,并且与含油量呈正相关。油污土壤中氮、磷等营养物质含量不足时,向其添加一定数量的营养物质和降解菌,能够提高微生物处理地面溢油的处理效率。     

Determination of polyacrylamide in soil waters by size exclusion chromatography

Determination of polyacrylamide (PAM) concentration in soil waters is important in improving the efficiency of PAM application and understanding the environmental fate of applied PAM. In this study, concentrations of anionic PAM with high molecular weight in soil waters containing salts and dissolved organic matter (DOM) were determined quantitatively by size exclusion chromatography (SEC) with ultraviolet (UV) absorbance detection. Polyacrylamide was separated from interferential salts and DOM on a polymeric gel column eluted with an aqueous solution of 0.05 M KH2PO4 and then detected at a short UV wavelength of 195 nm. Analysis of PAM concentrations in soil sorption supernatants, soil leachates, and water samples from irrigation furrow streams showed that SEC is an effective approach for quantifying low concentrations (0-10 mg L(-1)) of PAM in waters containing soil DOM and salts. The method has a lower detection limit of 0.02 microg and a linear response range of 0.2 to 80 mg L(-1). Precision studies gave coefficients of variation of < 1.96% (n = 4) for > 10 mg L(-1) PAM and < 12% (n = 3) for 0.2 to 3 mg L(-1) PAM.     

Polyacrylamide distribution in columns of organic matter-removed soils following surface application

Knowledge of how polyacrylamide (PAM) penetrates and distributes in a soil profile after application in irrigation water is important for understanding PAM conditioning depth and evaluating its environmental effects. Little is known, however, about PAM distribution in soil because of the difficulty in quantifying PAM content in natural soils. By using a recently modified substrate-borne PAM quantification method, PAM distribution in columns of organic matter-removed soils was determined. Results showed that penetration of PAM into the soil was affected by salt level of irrigation water, soil texture, initial soil water content, water application method, and other factors. Polyacrylamide penetration depth was about one-eighth to one-half of the water penetration depth, with a particularly high PAM retention in the top few centimeters of the soil. Under different experimental conditions, the PAM retained in the top 0 to 2 cm of soil ranged from 16 to 95% of the total applied amount. More favorable solution-soil contact conditions, longer solution-soil contact time, and lower initial soil moisture caused much more PAM retention in the top few centimeters of the soil. High sorptive affinity of PAM on soil is the main reason for its low penetration into the soil. Although these results were not obtained from natural soils, they are still helpful in improving our understanding of PAM transport behavior in soils.     

我国聚合物驱采出水处理方法研究进展

聚合物驱采油技术为我国东部各油田的原油稳产奠定了坚实的基础,但因对聚合物驱油采出水的处理难度大而制约了油田的发展。对油田含聚污水的处理工艺、回注可行性以及HPAM降解方法进行了分析,综合论述了含聚污水处理的研究现状。     

INFILTRATION OF WASTEWATER AND SIMULATED RAINWATER AS AFFECTED BY POLYACRYLAMIDE1

ABSTRACT: Irrigation reduces infiltration rates for subsequent irrigations or rains, thus decreasing the efficiency of water use and impacting watersheds in agricultural areas. Reduced infiltration causes greater runoff with its accompanying erosion, pollution, and sedimentation. Small rates of polyacrylamide (PAM) improve infiltration and reduce erosion on irrigated fields. The effects of PAM on infiltration of rainwater, the longevity of the effects of various rates of PAM, and the effects of repeated or intermittent PAM applications are not understood. This study measured the effects of four PAM application rates (0, 10, 25, and 40 ppm) on the subsequent infiltration of wastewater or simulated rainwater for seven weeks following the initial treatments. Also, effects of repeated and intermittent PAM applications on infiltration were determined. Hydraulic conductivity was determined for each soil column using the falling head method. Two soil types from the coastal plain of south Texas were tested — a soil high in clay (Victoria) and a sandy loam (Willacy). Effects of PAM rates were significant, but effects of water type were not (P > 0.05). Benefits from single PAM applications disappeared within two weeks. Water enriched with PAM is so viscous and infiltrates so slowly that applying PAM in every irrigation event may not be feasible. However, repeating PAM applications every two weeks maintained high infiltration rates on the alternate weeks. This intermittent application of PAM may be a practical approach for improving infiltration rates on irrigated lands.     

油田采出水微波处理技术探讨

微波应用于油田采出水处理,具有辅助絮凝、杀菌、降低腐蚀的作用。实验表明:应用微波处理油田采出水,可使PAC(聚合氯化铝)加量减少20%、PAM(聚丙烯酰胺)减少30%,处理时间仅为常规工艺的1/4,微波处理60s可将采出水中的TGB(腐生菌)、FEB(铁细菌)、SRB(硫酸盐还原菌)杀死99%以上,与常规工艺相比,微波处理后水质腐蚀率可下降20%以上。     

Salinity management using an anionic polymer in a pecan field with calcareous-sodic soil

Soil salinity and sodicity have long been recognized as the major concerns for irrigated agriculture in the Trans-Pecos Basin, where fields are being flood irrigated with Rio Grande River water that has elevated salinity. Reclamation of these salt-affected lands is difficult due to fine-texture, high shrink-swell soils with low permeability. Conventional practice of subsoiling to improve soil permeability is expensive and has had limited success on the irrigated soils that have appreciable amounts of readily weatherable Ca minerals. If these native Ca sources can be effectively used to counter sodicity, it can improve soil permeability and reduce amelioration costs. This study evaluated the effects of 3 yr of polyacrylamide (PAM) application at 10 mg L concentration during the first irrigation of the season to evaluate soil permeability, in situ Ca mineral dissolution, and leaching of salts from the effective root zone in a pecan field of El Paso County, TX. Results indicated that PAM application improved water movement throughout the effective root zone that resulted in Na leaching. Polymer application significantly decreased CaCO (estimated based on inorganic C analysis) concentrations in the top 45 cm compared with baseline levels, indicating solubilization and redistribution of calcite. The PAM application also reduced soil electrical conductivity (EC) in the top 60 cm (4.64-2.76 dS m) and sodium adsorption ratio (SAR) from 13.1 to 5.7 mmol L in the top 75-cm depths. As evidence of improved soil conditions, pecan nut yields increased by 34% in PAM-treated fields over the control. Results suggested that PAM application helped in effective use of native Ca sources present in soils of the study site and reduced Na by improving soil permeability.