影响总磷的显色实验细节探讨

针对环境样品采用钼酸铵分光光度法测定的总磷中,影响显色的二个因素进行了分析,对加入显色刺后的混合过程对显色结果的影响,以及环境条件的温度对显色的影响进行了研究,对总磷测定时准确度及精密度的提高有着重要的参考价值,是对钼酸铵法测定总磷方法的完善。     

A mathematical approach for retrofit and optimization of total site steam distribution networks

This paper presents a generic mathematical model for retrofitting the steam power plants in an industrial site. The industrial sector under review consists of one steel mill, one oil refinery, and several petrochemical plants, where only small-scale steam integration has been implemented before this study. The relevant unit models in a typical steam power plant are established, and the steam plant retrofit problem is formulated as a mixed-integer nonlinear program (MINLP). Feasible retrofit alternatives suggested by experienced field engineers are investigated in sequence to examine the revenue of those possible modifications. The first scenario examines operational optimization of existent plants; the second option allows installation of one new turbine and replacement of several boilers and turbines with lower efficiency; the third scenario considers using a steam ejector to upgrade the disqualified import steam in the oil refinery. The significant merits from these three retrofit alternatives show that the proposed MINLP formulation has been a great help to enhance the inter-plant steam integration in an industrial sector.     

Enhancing generic ecological model for short-term prediction of Southern North Sea algal dynamics with remote sensing images

Physically based numerical modelling follows from the basic understanding of the underlying mechanisms and is often represented by a set of (partial differential) equations. It is one of the main approaches in population dynamics modelling. The emphasis of the model introduced in this paper is on the simulation of short-term spatial and temporal dynamics of harmful algal bloom (HAB) events. Total suspended matter (TSM) concentration is one of the dominant factors for harmful algal bloom (HAB) prediction in North Sea. However, the modelling of suspended matter contains a high degree of uncertainty in this area. Therefore, this research aims to achieve a better estimation for the short-term prediction of harmful algal bloom development in both space and time by using spatially distributed TSM retrieved from remotely sensed images as physically based model inputs. In order to supply complete spatially covered datasets for the physically based model instrument: generic ecological model (GEM), this research retrieves TSM information from MERIS images by means of proper estimation techniques including biharmonic splines and self-learning cellular automata. A better estimation of HAB spatial pattern development is achieved by adding spatially distributed TSM data as inputs to original GEM model, and it proved that chlorophyll-a concentration in this area is very sensitive to TSM concentration.     

总磷排放标准的讨论

总磷是评价水质的重要指标,磷以多种形式存在,随着污水排放标准的不断更新．总磷标准的尺度不相一致。根据国家相关标准和规范,给出了能让已有标准内在联系更加完整和协调的建议．期待环境行政管理部门对废水中总磷排放标准作出更加明确合理的相关规定．     

水中总硬度测量不确定度的评定

采用EDTA滴定法测定水质总硬度的测量不确定度评定。充分考虑测量重复性、标准溶液的配制、滴定等过程对测量的影响,计算水中总硬度的测量相对合成标准不确定度为1·81×10-3。     

沈阳市浑南新区二氧化硫总量控制研究

为了实现浑南新区的规划目标,必须对新区SO2 进行总量控制。本文利用A—P值法对浑南新区SO2 的总量控制进行研究,给出了整个新区SO2 的总量控制目标及规划中的各个高架点源污染源的总量控制目标,为新区总量控制的实施提供了决策依据。     

包头市大气氟化物排放总量控制管理研究

结合实践,阐述了总量控制管理的必要性和可能性;介绍和分析了总量管理的内容和程序;对主要问题提出对策和措施;形成运行管理机制,提出排氟量计算、污染物输送扩散模型等构成的技术支持系统。      

大气污染物排放总量控制技术支持体系的建立

为了实施总量控制,在大气环境质量未达标区制定大气污染物排放削减量优化分配方案。得出污染源年度削减限量;在空气质量达标区.依照允许的地面浓度增量,将大气污染物允许排放指标合理地分配到源,以保证经济的持续发展;在大气环境管理中逐步建立起计算机辅助决策支持系统和完善的监测系统。      

常见沉水植物对草海水体(含底泥)总氮去除速率的研究

利用狐尾藻?菹草?苦草?伊乐藻?金鱼藻?篦齿眼子菜?轮藻等7种沉水植物对受污染的草海水体(含底泥)总氮去除速率进行了试验研究?结果表明:每种沉水植物对水体总氮?总磷均有显著去除作用,在试验的27d内,对总氮?总磷的去除百分率分别为80.31%,89.82%;重点对7种沉水植物引起水体总氮浓度下降与时间的关系作回归分析,所得结果是随着时间的延长,水体中总氮浓度呈负指数形式衰减?该文还研究了水体总氮浓度与去除速率之间的关系?每种沉水植物在试验的总氮浓度范围内(2.628～16.667mg/L)去除速率随总氮浓度的增加而增加?对TN_{_t}曲线和V-TN曲线在大型水生植物系统恢复中的应用进行了讨论?      

包头市大气氟化物总量控制排放许可证研究

总结了包头市实施大气排污许可证制度试点中,关于氟化物总量控制许可值的确定方法,主要包括源强的确定、大气扩散模式筛选与验证、总量控制区划定与执行标准、控制点选择、污染源贡献率和削减量计算、许可值的优化分配。