A Digital Filter for the State Estimation of Impulsive Noise Under the Existence of a Background Noise and its Experiment in the Work Environment

In the actual work environment, a specific objective noise, like machine and industrial noises, shows impulsive fluctuation form. Furthermore, it often occurs that a specific noise is partially or completely contaminated by background noise. In that case, the fluctuation wave form of the specific noise has to be estimated moment by moment in order to evaluate and/or improve the work environment. In this study, a digital filter for estimating an impulsively fluctuating specific noise is proposed. More specifically, after introducing a generalized time series regressive model of the specific noise, a method for estimating the impulsive noise based on an observation contaminated by the background noise is theoretically derived. Furthermore, the proposed method is applied to the actual task of estimating an industrial impact noise.     

填料在净化污水过程中渗透性能变化趋势的研究

选取腐殖垃圾和砂以及两者质量比分别为4:1、3:2、2:3的混合物共5种填料,在1.0 m/d的水力负荷下,进行人工快速渗滤系统净化生活污水的试验,研究填料在进水过程中渗透性能的变化趋势.结果表明,腐殖垃圾的初始饱和水力渗透系数(K)最大,为3.32×10-2cm/s,而砂的初始K只有5.14×10-3cm/s,腐殖垃圾含量越大的混合物其仞始K也越大.在净化污水的过程中,5种填料的K逐渐减小,腐殖垃圾含量越大的混合物其K降幅也越大.随着进水时间的延长,各个填料柱填料层50～250 mm处的水头损失占总水头损失(填料层50～450mm处)的比例均逐渐增加,最终各个填料柱均发生堵塞,堵塞均发生在填料层50mm以上范围内.     

Evaluation of an activated carbon filter for the retention of selected pesticide vapours

Abstract

An activated charcoal bed unit (ACBU) was constructed using teflon stock. The unit duplicated the flow and bed design of a commercially available tractor mounted filter for removing pesticides from the air.

Eight pesticides (4 herbicides and 4 insecticides) were used to test the retention efficiency of ACBU over a 12–48 h period with the ACBU in place. Polyurethane foam (PUF) plugs in series trapped any residual pesticide that came through the ACBU.

The ACBU retained 93–100% of the pesticides tested. The unit thus provides an efficient mechanism for removing airborne pesticides.     

新型复合滤料过滤性能的实验研究及其应用

针对袋式除尘器滤料运行阻力过高问题 ,介绍了一种新型结构的复合滤料 (HBT)。对其过滤性能进行实验研究 ,结果表明在相同工况下 ,该滤料具有“高效低阻”特性 ,并在实际工程应用中取得了较好的效果。     

两段曝气生物滤池工艺在沈阳仙女河污水处理厂的应用

沈阳仙女河污水处理厂采用了两段曝气生物滤池 (BAF)工艺。其主要特点是具有体积小处理效率高、出水水质好、流程简单 ,集生物氧化和截流悬浮固体于一体 ,在有效去除水中的有机物的同时 ,脱氮效果良好。该工艺不设二沉池 ,节省了基建投资 ,且自动化控制水平高 ,降低了运行成本。     

热轧浊循环水处理的中试研究

应用处理量8m3/h的压紧式改性纤维球压力过滤器,对某钢铁厂热轧浊循环水进行处理。结果表明,采用纤维球过滤能有效的去除热轧浊循环水中的油类和悬浮物(SS),过滤后的出水中油含量能降低到1.8~4.5mg/L,去除率达到84.5%,悬浮物(SS)最高9.5mg/L,平均5.04mg/L,去除率达到88.77%,满足该厂要求热轧循环用水油含量≤5mg/L,悬浮物≤10mg/L的要求。     

布袋收尘穿漏报警系统实验研究

简述了布袋收尘穿漏报警技术研究的意义及发展趋势,介绍了布袋收尘穿漏报警系统实验研究结果。     

两级曝气生物滤池实用性综合分析

两级曝气生物滤池工艺主要特点是体积小、处理效率高、出水水质好、流程简单,集生物氧化和截流悬浮固体于一体,在有效去除水中的有机物的同时,脱氮效果良好。该工艺不设二沉池,节省了基建投资,且自动化控制水平高,也降低了运行成本。本文综合介绍了该工艺的工艺流程、设计要点、技术经济分析和运行状况等。