超稠油污水深度处理工艺技术

针对辽河油田超稠油污水的特点设计了处理工艺流程,进行了药剂的筛选,根据各工艺设备的出水水质要求确定了合适的净水剂、除硅剂、阻垢剂的加量,并进行了现场实际应用,外输出水达到锅炉给水指标要求,用于锅炉注汽使用,效果良好,分析了该超稠油污水处理技术的特点和优势,提出了超稠油污水回用锅炉的建议。     

Physical and Sanitary Quality of Hand-Dug Well Water from Oil-Producing Area of Nigeria

The physical (pH, Dissolved Solids, Dissolved Oxygen, conductivity, water depth temperature) and bacteriological (Total coliforms, Faecal coliforms) characteristics of 22 hand-dug wells in oil-rich Niger Delta of Nigeria were investigated. All coliforms counts (Log₁₀ MPN/100 ml) varied from well to well ranging from 0 to 6.0 although faecal coliform counts were markedly lower (0–3.5 vs 1.0–6.0). When both seasons were compared, faecal coliform counts were significantly higher (t test; P < 0.05) during the wet season whereas no significant difference was observed in respect of total coliforms. Unlike the total coliforms, faecal coliform counts increased in wells close to septic tanks during the wet season. Although a declining trend was observed during the wet season, the values of the physical parameters were within WHO limits. The pH was slightly acidic (Mean ± SD: dry season, 6.04 ± 0.66; wet, 6.43 ± 0.62) and may be attributed to emissions from gas flaring and petroleum refining activities, which is common in the area. While the total coliform counts reflected the unsanitary habits of the well users, the detection of faecal coliforms exceeding recommended numbers in 63% of the wells render them unfit for domestic use. The public health implication is obvious considering the increasing number of people using the wells due to the rapid urbanization of the oil-rich region.     

Coliforms removal in full-scale activated sludge plants in India

This paper investigates the removal of coliforms in full-scale activated sludge plants (ASP) operating in northern regions of India. Log2.2 and log2.4 removal were observed for total coliforms (TC) and fecal coliforms (FC), respectively. However, the effluent still contained a significant number of TC and FC which was greater than the permissible limit for unrestricted irrigation as prescribed by WHO. The observations also suggest that extended aeration (EA) process operating under high mixed liquor suspended solids (MLSS) and sludge retention time (SRT) is more efficient in the removal of coliforms. Further attempts have been made to establish the relationship between two key wastewater parameters, i.e. biochemical oxygen demand (BOD) and suspended solids (SS) with respect to fecal and TC. The relationships were observed to be linear with a good coefficient of correlation. The interrelationship of BOD and SS with coliforms manifest that improvement of the microbiological quality of wastewater could be linked with the removal of SS. Therefore, SS can serve as a regulatory tool in lieu of an explicit coliforms standard.     

Using turbidity and acoustic backscatter intensity as surrogate measures of suspended sediment concentration in a small subtropical estuary

The suspended sediment concentration is a key element in stream monitoring, although the turbidity and acoustic Doppler backscattering may be suitable surrogate measures. Herein a series of new experiments were conducted in laboratory under controlled conditions using water and mud samples collected in a small subtropical estuary of Eastern Australia. The relationship between suspended sediment concentration and turbidity exhibited a linear relationship, while the relationships between suspended sediment concentration and acoustic backscatter intensity showed a monotonic increase. The calibration curves were affected by both sediment material characteristics and water quality properties, implying that the calibration of an acoustic Doppler system must be performed with the waters and soil materials of the natural system. The results were applied to some field studies in the estuary during which the acoustic Doppler velocimeter was sampled continuously at high frequency. The data yielded the instantaneous suspended sediment flux per unit area in the estuarine zone. They showed some significant fluctuations in instantaneous suspended mass flux, with a net upstream-suspended mass flux during flood tide and net downstream sediment flux during ebb tide. For each tidal cycle, the integration of the suspended sediment flux per unit area data with respect of time yielded some net upstream sediment flux in average.     

A long-term survey on anthropogenic impacts to the water quality of coral reefs, southern Taiwan

Before 2001, the ecological protection area in the Kenting National Park (KTNP), southern Taiwan, was poorly described. In this study, a set of four-year data (2001-2004) of seawater qualities at 19 sampling sites around the Nanwan Bay in the KTNP was used to explore anthropogenic impacts to ecological environment, especially coral reefs. The parameters of water quality were analyzed immediately after collection. The results showed that higher values of nutrients and suspended solids were attributed to the higher run-off around Nanwan Bay. The fluxes of nutrients and suspended solids were consistently correlated to rainfall. Hence, equations were developed to calculate nutrient fluxes and suspended solids by using only rainfall data. Our results show that suspended solids and ammonia were the dominant factors leading to the drop in coral coverage. In summary, the water quality in the intertidal zone of Nanwan Bay has been degraded and required greater attention.     

利用基因工程菌BL21处理有机磷混合农药废水的研究

研究了悬浮状态和固定化状态的基因工程菌BL21对有机磷混合农药废水的降解特性.工程菌能快速、高效地降解有机磷混合农药,其最适底物是对硫磷,而马拉硫磷不能被工程菌降解.不同农药降解速率的差别造成了不同有机磷农药的降解过程需要用不同的动力学模型来描述.比较固定化状态和悬浮状态的工程菌的降解效果可知,固定化工程菌的降解活性较后者明显降低,其比降解速率大约仅为后者的20%.考察固定化工程菌长期运行的效果,发现其降解活性保存良好,工程菌稳定性大大提高,未出现固定化细胞溶涨、破碎现象.固定化后,工程菌的比降解速率虽然比悬浮工程菌降低了,但固定化工程菌更适用于长期运行的废水处理系统.     

Assessment of sediment concentration and nutrient loads in effluents drained from extensively managed fishponds in France

Expansion of aquaculture has increased concern over its environmental impact. The composition of effluents from intensive aquaculture is well documented, but few data on extensive aquaculture are available. During 12 draining operations, 523 water samples were collected downstream from six extensively-managed fishponds in northeastern France. Study ponds had surface areas of 2-620 ha and were managed for production of Cyprinids and Percids. Concentrations of total suspended solids, total phosphorus, and Kjeldahl nitrogen in effluents from the ponds were greatest during the final stage of draining. Loads of phosphorus were higher than those reported for effluents of more intensive aquaculture ponds in the USA, but the source of the potential pollutants was catchments and sediment rather than feeds and fertilizer. It will be necessary to reduce the water drawdown rate during the fishing stage and possibly implement other best management practices to prevent the TSS concentration from exceeding 1 g/L.     

地表水中悬浮物含量和粒径对磷测定的影响

我国地表水体悬浮物含量和颗粒粒径组成的时空分异明显。该研究筛分3种粒径颗粒,研究不同粒径颗粒中赋存的磷形态及其解吸-吸附磷的能力特性差异,探讨不同悬浮物含量引起水体总磷(TP)测定结果偏差情况及改进建议。结果表明,粒径d<30 μm颗粒所赋存总磷、生物有效态磷含量明显高于50~150 μm、30~50 μm颗粒,水空白环境下粒径<30 μm颗粒所释放磷量也最高,等温吸附条件下粒径<30 μm颗粒具有更高的磷吸附能力。通过Freundlich交叉型吸附曲线拟合,粒径50~150 μm、30~50 μm、<30 μm颗粒的磷解吸-吸附平衡质量浓度分别为0.84、0.63、0.58 mg/L,粒径<30 μm颗粒在地表Ⅰ~Ⅴ类水体(TP≤0.4 mg/L)中更易达到磷解吸-吸附平衡状态。我国地表一般水体中悬浮物含量大多在零至几千mg/L范围,而使用 "静沉30min-消解" 国标前处理方法无法保证统一的沉降效果,使得水体TP含量测定结果偏低或偏高。针对地表一般水体,建议同时增加"混匀-消解-过滤"前处理方法测定水体TP含量作为参考。