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551.
The decomposable waste thrown into the environment can be used to produce value added bio-product which in turn reduces the production of greenhouse gas. Garbage enzyme is one such value added product produced by fermentation of organic solid waste. In the present study enzyme activity and disinfectant potential of garbage enzyme was evaluated and its influence on reduction of total solids, suspended solids and pathogens in dairy waste activated sludge were studied. The result showed the garbage enzyme possesses protease, amylase and lipase activity and reduced 37.2% of total solids, 38.6% of suspended solids and 99% of pathogens in dairy waste activated sludge. This significant result may be helpful for researchers to compare the effectiveness of earth-friendly garbage enzyme treatment of industrial sludge with various physical and chemical pre-treatment methods to improve the biogas production from the sludge digestion unit. 相似文献
552.
The increasing use and subsequent accumulation of polystyrene containers has triggered a substantial environmental problem. This study investigated using varied percentages of solid waste polystyrene disposable food dishes in the production of lightweight concrete samples with 350 kilograms per cubic meter (kg/m3) of cement and a density of 1,300 kg/m3. The polystyrene disposable dishes were ground into beads of 0–3 millimeters (mm) and 3–6 mm in size. First, the characteristics of Type II Portland cement, polystyrene, and aggregates were examined. The following characteristics of concrete using ASTM International and British Standards Institution standards were tested: slump, compressive strength, ability to resist chloride ion penetration, and resistance of concrete to rapid freezing and thawing cycles. Scanning electron microscopy (SEM) and energy dispersive X‐ray spectroscopy analytical techniques were also used. The slump of samples varied between 40 and 70 mm and was not dependent on either the polystyrene percentage or the size of the polystyrene beads in the concrete samples (p‐value > .05). The compressive strength of the concrete samples after 90 days of curing, and using different percentages of polystyrene, varied between 96 and 113 kilograms per square centimeter (kg/cm2). The resistance of the samples to the freezing and thawing cycle and chloride ion penetration were affected unfavorably by the presence of the polystyrene. The SEM technique indicated that concrete samples containing 15% and 25% polystyrene had denser crystals and less void than concrete samples with 40% and 55% polystyrene. 相似文献
553.
水分调节材料对牛粪堆肥氨气挥发的影响 总被引:2,自引:0,他引:2
利用通风式堆肥发酵方式研究了牛粪堆制过程中氨气的挥发特征和锯末、稻壳、稻草等不同水分调节材料对氨气挥发的影响。结果表明,牛粪堆制过程中主要在前期,尤其是在最初的2周内释放氨气;堆肥期间挥发的氨态氮约为牛粪总含氮量的17%~50%。不同水分调节材料都可以在一定程度上抑制氨气的挥发,但锯末抑制氨气挥发效果最好,其次是稻壳,稻草抑制氨气挥发的效果较小。因此,为了减少氮素损失,应采取适当措施抑制氨挥发或回收挥发的氨气。 相似文献
554.
超滤技术在环境工程中的应用现状 总被引:10,自引:0,他引:10
本文对国内外超滤技术在环境工程中的应用,主要是废水处理中的应用现状进行了综述。涉及的废水包括纺织工业,机械制造工业,石油化工工业,食品加工工业及其它工业污水,也包括部分生活污水,在这些污水治理过程中,不仅可消除或减轻污水对环境的污染,同时也可以回收有价值的物质,使水部分或全部回用。 相似文献
555.
以城市垃圾焚烧后的残渣为研究对象 ,着重地介绍城市垃圾焚烧炉中灰渣的形成、结构、组成等基本性质 ,同时借鉴燃煤技术初步探讨了城市垃圾焚烧过程中结渣的形成。对垃圾焚烧炉的正常运行提供科学的保证 ,对残渣的管理及综合利用有一定的意义 相似文献
556.
557.
Certain radioactive waste storage tanks at the United States Department of Energy Hanford facilities continuously generate gases as a result of radiolysis and chemical reactions. The congealed sludge in these tanks traps the gases beneath it and causes the level of the waste within the tanks to rise. The waste level continues to rise until the sludge loses its buoyancy and rolls over, changing places with fluid on top. During a rollover, the trapped gases are released, resulting in a sudden drop in the waste level. This is known as a gas release event (GRE). After a GRE, the waste re-congeals and gas again accumulates, leading to another GRE. We are interested in the time between consecutive GREs. Understanding the probabilistic behaviour of the time between consecutive GREs is important because the hydrogen and nitrous oxide gases released during a GRE are flammable and the ammonia that is released is a health risk. From a safety perspective, activity around such waste tanks should be halted when a GRE is imminent. With a credible probability model for the time between consecutive GREs, we can establish time windows in which waste tank research and maintenance activities can be safely performed. We discuss the application of non-linear time series models to this problem. 相似文献
558.
超高浓度萘系磺酸染料中间体废液资源化 总被引:1,自引:0,他引:1
王连生 《城市环境与城市生态》1995,8(3):11-14
本文介绍了胺盐萃取回收率液中萘磺酸染料中间体的方法,回收率达95%以上,回收浓缩液工艺套用,10t/d废液量的资源化年净效益达580万元,投资费用两个月即可全部收回,采用Langmuir等温方程描述体系中萃取剂用量,待萃物含量和萃取率的关系,使工艺参数的确立和工程设计完全处理指导之下。 相似文献
559.
城市污水回用三种处理工艺的选择 总被引:1,自引:0,他引:1
本文针对我国城市二级出水的特点,研究了污水深度处理的三种工艺:絮凝沉淀过滤、微絮凝过滤和直接过滤.装置采用网格反应池、翼片斜板沉淀池、气水同时冲洗粗砂滤池.药剂选用聚合硫酸铁,试验规模120m~3/d. 相似文献
560.
本文讨论了沉淀法和空气提气法去除电解锰废水中含有的锰(Mn~(2+))和氨-氮(NH_3-N),并研究了该方法的最佳条件,为废水日排放量在300—400T之间的工厂设计了废水处理路线。结果表明,上述方法处理后的废水中Mn~(2+)和NH_3-N含量达到或低于国家污水排放标准。 相似文献