水解酸化-CASS工艺处理水产加工废水

采用水解酸化-CASS工艺处理水产加工废水,实践表明工艺合理、技术先进、设备投资小、运行费用低,污水处理后达到<污水综合排放标准>(GB 8978-96)中的一级排放标准.     

丝状菌在工业废水处理中的控制与有效利用

任何活性污泥系统中都存在着丝状菌,在丝状菌与菌胶团细菌平衡生长时,不会发生膨胀污泥问题,只有当丝状菌生长超过菌胶团细菌时,就会出现污泥膨胀问题。丝状菌在工业废水中的有效控制与利用尤为重要。     

CASS工艺水力停留时间的实验研究

结合姜堰市城市生活污水处理厂运行,对CASS工艺中水力停留时间对COD、TN和NH3-N去除率的影响进行了探讨。通过运行工况和进水水质的改变试验,以积累大量的试验运行数据和实际处理效果,探讨水力停留时间对去除率的影响,确定适宜的水力停留时间。实验研究表明,水力停留时间控制在18h比较适宜,这样既经济又可以获得较稳定的处理效果。     

染料生产废水处理工程实践研究

针对还原性染料生产废水组成复杂、难降解等特点,采用二级处理工艺,一级处理系统包括格栅、调节池、微电解床、中和沉淀,二级处理系统包括水解酸化、CASS工艺、浅层气浮。整个废水处理系统一年多的运行结果表明,该处理工艺总体COD去除率大于88%,对色度和难降解有机物有良好的去除效果,同时耐冲击能力较强,运行效率高,运行费用低,具有很高的推广应用价值。     

碳青霉烯系列医药中间体生产废水治理技术应用研究

采用“气浮＋三效蒸发＋Ic＋CASS＋BAF”工艺处理碳青霉烯系列医药中间体生产废水。总处理水量为84t／d：进水水质：COD：58650mg／L、氨氮：203mg／L、盐分：106000mg／L。经该工艺处理后,废水中的COD、氨氮、盐分等指标均能迭标排放。     

气浮-水解酸化-CASS工艺处理番茄制品生产废水的工程应用

番茄制品生产废水含有大量糖类、有机酸,有机物浓度高,易于生化降解,采用气浮-水解酸化-CASS处理工艺,工程应用表明,出水可达GB 8978—1996《污水综合排放标准》一级排放标准,且投资省、运行费用低,具有适用范围广、抗冲击负荷能力强等特点,具有较高的推广应用价值。     

水解酸化-混凝气浮-CASS工艺在屠宰废水处理中的应用

介绍了某生猪屠宰企业采用水解酸化-混凝气浮-CASS组合工艺处理屠宰废水的工程应用。工程实践表明,在CASS系统中投加淀粉补充碳源,经处理后的出水中各项指标均达到当地污水排入城市下水道水质标准。     

水解酸化-改良UASB-填料CASS工艺处理酒精废水研究

某企业污水站采用UASB-CASS工艺处理玉米酒精生产废水,为解决其出水水质不稳定的问题,根据废水水质特点,对企业现有工艺进行改造,采用水解酸化-改良UASB-填料CASS工艺开展中试试验研究.试验结果表明,前置水解酸化有助废水的后续生化处理,改良UASB有助缩短反应器启动时间和,CASS池中填料的投加有利于活性污泥附着、生长更新,该组合工艺在进水水质波动的情况下,出水COD质量浓度由工艺改造前的100.0～ 150.0 mg/L降至50.45～80.38 mg/L,出水NH4+-N质量浓度由工艺改造前的1.0～3.0 mg/L降至0.31 ～ 0.62 mg/L,大大削减了污染物排放量.     

CASS工艺在某县城市污水处理厂应用实例研究

某县污水厂规模1.8万m3/d,采用CASS工艺进行城市污水处理,通过对污水曝气时间、污泥回流比、DO浓度、MLSS等条件进行控制,出水水质满足《城镇污水处理厂污染物排放标准》(GB 18918-2002)一级B排放标准要求,工艺对该污水具有较好的适应性.与其他CASS工艺运行情况相比,该厂CASS工艺设定曝气时间长,能耗高,宜根据水质水量的变化,调节设备运行台数及曝气时间,实现能耗的降低.     

Safety performance evaluation of cable median barriers on freeways in Florida

Objective: This article aims to evaluate the safety performance of cable median barriers on freeways in Florida.

Method: The safety performance evaluation was based on the percentages of barrier and median crossovers by vehicle type, crash severity, and cable median barrier type (Trinity Cable Safety System [CASS] and Gibraltar system). Twenty-three locations with cable median barriers totaling about 101 miles were identified. Police reports of 6,524 crashes from years 2005–2010 at these locations were reviewed to verify and obtain detailed crash information. A total of 549 crashes were determined to be barrier related (i.e., crashes involving vehicles hitting the cable median barrier) and were reviewed in further detail to identify crossover crashes and the manner in which the vehicles crossed the barriers; that is, by either overriding, underriding, or penetrating the barriers.

Results: Overall, 2.6% of vehicles that hit the cable median barrier crossed the median and traversed into the opposite travel lane. Overall, 98.1% of cars and 95.5% of light trucks that hit the barrier were prevented from crossing the median. In other words, 1.9% of cars and 4.5% of light trucks that hit the barrier had crossed the median and encroached on the opposite travel lanes. There is no significant difference in the performance of cable median barrier for cars versus light trucks in terms of crossover crashes. In terms of severity, overrides were more severe compared to underrides and penetrations. The statistics showed that the CASS and Gibraltar systems performed similarly in terms of crossover crashes. However, the Gibraltar system experienced a higher proportion of penetrations compared to the CASS system. The CASS system resulted in a slightly higher percentage of moderate and minor injury crashes compared to the Gibraltar system.

Conclusions: Cable median barriers are successful in preventing median crossover crashes; 97.4% of the cable median barrier crashes were prevented from crossing over the median. Of all of the vehicles that hit the barrier, 83.6% were either redirected or contained by the cable barrier system. Barrier crossover crashes were found to be more severe compared to barrier noncrossover crashes. In addition, overrides were found to be more severe compared to underrides and penetrations.