粉末活性炭在水源突发污染中的应用研究

通过烧杯试验的方法,研究粉末活性炭对挥发酚的吸附性能,确定合适的投炭点和投炭量,为水源突发污染应急处理提供参考。试验结果表明:粉末活性炭对挥发酚的吸附规律满足Henry型吸附等温线;吸附时间是影响去除率的最主要因素,混凝竞争吸附现象不明显,投炭点选择在工艺前端为宜;投炭量对去除率的影响较大,挥发酚初始浓度基本无影响,当投炭量在30~40mg/L,去除率为50~60%。     

粉末活性炭去除水中石油类污染物的试验研究

以0#柴油为研究对象,考察了粉末活性炭对水中石油类污染物的吸附性能.结果表明,采用粉末活性炭可有效去除水中的石油类污染物,当柴油初始质量浓度为3 mg/L,吸附时间为30 min,投炭量为20 mg/L时,纯水及原水条件下柴油的去除率均大于70％,且在最大投炭量(80 mg/L)条件下,粉末活性炭可以应对在纯水和原水条...     

粉末活性炭吸附水中四氯化碳试验研究

采用粉末活性炭吸附去除水中四氯化碳,考察了活性炭投加量、吸附时间、温度等因素对去除效果的影响.结果表明,该吸附过程符合Freundlich吸附等温线模式,以物理吸附为主,并且在纯水中的吸附容量大于原水;在15-25℃內,温度对吸附效果的影响不大,但去除率随吸附时间的延长而升高;投加80 mg/L粉末活性炭吸附120 m...     

粉末活性炭对水中呋喃丹的吸附性能研究

考察了粉末活性炭吸附去除水中呋喃丹的可行性,并采用Freundlich公式拟合去离子水和自来水条件下的吸附等温方程.结果表明,采用粉末活性炭可有效去除水中的呋喃丹,在去离子水条件下,呋喃丹初始质量浓度为0.035 mg/L,投炭量为20 mg/L,吸附时间为120 min时,呋喃丹的去除率大于98％.根据吸附等温方程计...     

粉末活性炭对甲基对硫磷和对硫磷的去除研究

通过对粉末活性炭吸附特性的研究,探讨了活性炭工艺去除饮用水中甲基对硫磷和对硫磷有机磷农药的可行性。用Freundlich公式拟合吸附等温线的数据,并用来估算活性炭的吸附容量和最大投加量。试验结果表明,向甲基对硫磷、对硫磷浓度分别为0.22,0.06mg/L的配水中投加10mg/L粉末活性炭,吸附时间20min时两者的去除率为93.66%～98.11%。针对南方某水厂原水,试验所确定的活性炭最佳投加量为1.5～2.0mg/L。试验证明投加粉末活性炭是去除饮用水中甲基对硫磷和对硫磷的有效方法。     

投加粉末活性炭处理长江南京段微污染原水研究

针对长江南京段微污染原水的水质情况并为给水厂的粉末活性炭应急投加提供依据，通过烧杯试验确定了适宜的活性炭炭种、投加量和投炭点。结果表明，投加煤质粉末活性炭较投加木质炭或椰壳炭更为经济合理，且投加点在流程上越靠前越有利于活性炭吸附作用的充分发挥；活性炭与混凝剂的竞争吸附现象并不明显。活性炭的投量需根据不同水源的水质情况通过试验确定，针对长江南京段的原水水质，试验所确定的活性炭最佳投量为20～30mg／L。     

粉末活性炭对内吸磷的吸附性能研究

研究了粉末活性炭对內吸磷的吸附去除效果以及吸附时间、活性炭投加量和水质条件对吸附效果的影响.结果表明,当內吸磷质量浓度为0.30 mg/L,活性炭投加量为20 mg/L时,在去离子水中吸附60 min后,出水內吸磷为0.02 mg/L;在去离子水中的吸附效果优于原水,在实际应用中需根据原水水质适当调整活性炭投加量或吸附...     

活性炭回流强化去除有机物的试验研究

以中置式高密度沉淀池为载体,向池内投加粉末活性炭,利用高密度沉淀池的污泥回流系统对粉末活性炭进行富集和回用,延长其在沉淀池中的停留时间,考察投加粉末活性炭后对有机物的强化去除效果,并进行了投炭量优化研究。结果表明:该投加方式能显著改善对有机物的去除效果,相比不投加炭,对CODMn的去除率提高了近10%。通过增加污泥回流比可减少投炭量,在去除率相同的情况下,污泥回流比为5%时的投炭量较回流比为3%时减少了34%,而较不回流投炭方式减少了77%。对有机物的去除效果是粉末活性炭吸附和生物强化共同作用的结果。     

粉末活性炭对邻苯二甲酸二乙酯的吸附性能研究

考察了投加粉末活性炭吸附去除水中邻苯二甲酸二乙酯的可行性,并采用Freundlich公式拟合纯水和原水条件下的等温吸附方程。试验结果表明,采用粉末活性炭可有效去除水中邻苯二甲酸二乙酯,活性炭投加量为30mg／L,吸附120min后,纯水和原水条件下邻苯二甲酸二乙酯去除率分别为93．3％和89．3％。根据吸附等温方程计算得出,以邻苯二甲酸二乙酯的标准限值（0．3mg／L）为平衡浓度,纯水、原水条件下最大投炭量（80mg／L）可应对的邻苯二甲酸二乙酯最高质量浓度分别为7．575和5．731mg／L。     

粉末炭去除饮用水中土霉味物质的影响因素研究

采用粉末活性炭（PAC）去除饮用水中2-甲基异莰醇（MIB）、2,4,6-三氯茴萫醚（TCA）、2-异丙基-3-甲氧基吡嗪（IPMP）和2-异丁基-3-甲氧基吡嗪（IBMP）等4种常见的土霉味物质,研究了PAC种类、PAC投加量、嗅味物质的初始浓度、余氯、水质等因素对PAC去除土霉味物质的影响。结果表明,PAC吸附对嗅味物质的去除主要发生在前1 h内;煤质PAC对MIB有更高的去除率;在一定的吸附时间和活性炭投加量下,PAC对痕量嗅味物质的去除率与其初始浓度无关;余氯和有机物的存在降低了PAC对嗅味物质的吸附容量,水质对去除嗅味物质也有很大的影响。     

饮用水中粉末活性炭应急处理技术研究

以遭受突发性2,4滴污染的水体作为研究对象,考察了粉末活性炭技术对受2,4滴污染原水的应急处理效果.结果显示,粉末活性炭可有效去除2,4滴污染物,吸附时间越长,去除率越高.与准一级动力学方程相比,准二级动力学方程拟合曲线能更好地与数据点重合,相关系数为0.99,由准二级动力学方程计算得出的吸附容量值与试验中实际得到的吸附容量值很接近.粉末活性炭吸附2,4滴的Freundlich模型拟合度优于Langmuir模型,且对2,4滴的吸附存在多分子层吸附.     

Reverse osmosis concentrate treatment via a PAC-MF accumulative countercurrent adsorption process

Organic pollutants in reverse osmosis (RO) concentrates from wastewater reclamation are mainly comprised of low molecular weight biorefractory compounds. Generally, advanced oxidation methods for oxidizing these organics require a relatively high level of energy consumption. In addition, conventional adsorption removal methods require a large dose of activated carbon. However, the dose can be reduced if its full adsorption capacity can be used. Therefore, the combined technology of powdered activated carbon (PAC) adsorption and microfiltration (MF) membrane filtration was studied to develop a countercurrent two-stage adsorption process. A PAC accumulative adsorption prediction method was proposed based on the verification of a PAC multi-stage adsorption capacity equation. Moreover, the prediction method was amended for a more accurate prediction of the effluent quality because adsorption isotherm constants were affected by the initial adsorbate concentration. The required PAC dose for the accumulative countercurrent two-stage adsorption system was 0.6 g/L, whereas that of the conventional adsorption process was 1.05 g/L when the dilution factor(F) was 0.1 and the COD and DOC removal rates were set to 70% and 68.1%, respectively. Organic pollutants were satisfactorily removed with less consumption of PAC. Effluent from this combined technology can be further reclaimed by an RO process to improve the overall recovery rate to between 91.0% and 93.8% with both economic and environmental benefits.     

Characteristics of competitive adsorption between 2-methylisoborneol and natural organic matter on superfine and conventionally sized powdered activated carbons

When treating water with activated carbon, natural organic matter (NOM) is not only a target for adsorptive removal but also an inhibitory substance that reduces the removal efficiency of trace compounds, such as 2-methylisoborneol (MIB), through adsorption competition. Recently, superfine (submicron-sized) activated carbon (SPAC) was developed by wet-milling commercially available powdered activated carbon (PAC) to a smaller particle size. It was reported that SPAC has a larger NOM adsorption capacity than PAC because NOM mainly adsorbs close to the external adsorbent particle surface (shell adsorption mechanism). Thus, SPAC with its larger specific external surface area can adsorb more NOM than PAC. The effect of higher NOM uptake on the adsorptive removal of MIB has, however, not been investigated. Results of this study show that adsorption competition between NOM and MIB did not increase when NOM uptake increased due to carbon size reduction; i.e., the increased NOM uptake by SPAC did not result in a decrease in MIB adsorption capacity beyond that obtained as a result of NOM adsorption by PAC. A simple estimation method for determining the adsorbed amount of competing NOM (NOM that reduces MIB adsorption) is presented based on the simplified equivalent background compound (EBC) method. Furthermore, the mechanism of adsorption competition is discussed based on results obtained with the simplified EBC method and the shell adsorption mechanism. Competing NOM, which likely comprises a small portion of NOM, adsorbs in internal pores of activated carbon particles as MIB does, thereby reducing the MIB adsorption capacity to a similar extent regardless of adsorbent particle size. SPAC application can be advantageous because enhanced NOM removal does not translate into less effective removal of MIB. Molecular size distribution data of NOM suggest that the competing NOM has a molecular weight similar to that of the target compound.