环境科学专业英语翻译环境科学专业英语翻译.docx

环境科学专业英语翻译专业：环境科学班级：0224121学号：022412111姓名：魏亚南3、 Results and discussion3、结果与讨论3.1 Flow velocity distribution in oxidation ditch。Change of flow velocity has a certain impact onnitrogen removal process of the oxidation ditch, with itsplug-flow effect and flow velocity as the variables tocontrol total nitrogen removal efficiency [11]. Flowvelocity could not only affect the sludge deposition, butalso affect the hydraulic cycle time of the oxidation ditch，the proportion of the residence time of aerobic andanoxic environment, dissolved oxygen, organic matter，and the distribution of sludge concentration directly. Inaddition, flow velocity was also a direct reflection of theextent of disturbance in the trench, playing an importantrole in the shape and size of sludge floc directly, whichwas the key factor of the occurrence of SND process inthe oxidation ditch。3.1：氧化沟中的流速分布(SND：同步硝化反硝化)流速的变化对氧化沟的脱氮过程有一定的影响。在控制总氮的去除效率过程中，氧化沟中的活塞流效率和流速是变量。流速不仅直接的影响污泥沉积，也直接影响氧化沟的水力循环时间，好氧和缺氧环境下停留时间的比例，溶解氧，有机物和污泥浓度分布，另外，流速也是氧化沟干扰程度的直接反映，在形成的污泥絮体的形状和大小上扮演重要的角色。污泥絮体在硝化和反硝化过程中是关键因素。As can be seen from Fig. 3, flow velocity of theoxidation ditch was affected by the aeration and thechanges of spatial location significantly, with the averagevelocity (0.140 m/s) in the trench of operating Condition2 (opening four aeration wheels) being higher thanthe mean velocity (0.124 m/s) in Condition 1 (with threeaeration wheels in operation). The velocity variations inthe horizontal and vertical directions were also obvious,with the average velocity at the bottom, middle, upperpart being 0.172, 0.122 and 0.127 m/s, which weresignificantly higher than the values (0.150, 0.106 and0.115 m/s) under Condition 1. In the two kinds ofoperating conditions, the flow velocity in the first cornerand inside of the cross section11 was low and there showed the evidence of sludgedeposition. Overall, the flow velocity in most of theregions in the two operating conditions of the oxidationditch was in the range of 0.1?0.2 m/s, with t