Case studies paper mill

The deep shaft biological treatment process,87 which is one of the activated sludge systems, has been successfully applied to a paper mill wastewater treatment in Japan (see Case Study III, Section 21.6.3). 

The scope of the case study is depicted in Fig. 2. In the inventory, average data on emissions and consumptions, typically based on 5-10 data points (depending on the parameter) from a total of 71 Danish and Swedish printing houses and European literature values, are used (foreground data). For the upstream and downstream emissions and consumptions (background data), inventory data from databases like EDIP LCV tool [12] and literature like BUWAL [13] and data from Swedish paper mills [14] have been used. In the main scenario, it is assumed that 53% of the paper is recycled and the rest incinerated (Danish situation in year 2000). 

Using the ZPE scheme, the study of effluent discharge situations at 16 Ontario pulp and paper mills demonstrated a majority of strong or moderately strong relationships between sublethal toxicity tests and ecosystem indicators (fish populations and benthic invertebrate communities). The locations of effects in benthic organisms corresponded in 100% of cases with zones predicted by the Ceriodaphnia test and in 81% of cases with predictions from the Selenastrum test. The fathead minnow test did not perform as well, predicting effects on fish in only 53% of cases (Moody, 2000). 

Membrane technology may become essential if zero-discharge mills become a requirement or legislation on water use becomes very restrictive. The type of membrane fractionation required varies according to the use that is to be made of the treated water. This issue is addressed in Chapter 35, which describes the apphcation of membrane processes in the pulp and paper industry for treatment of the effluent generated. Chapter 36 focuses on the apphcation of membrane bioreactors in wastewater treatment. Chapter 37 describes the apphcations of hollow fiber contactors in membrane-assisted solvent extraction for the recovery of metallic pollutants. The apphcations of membrane contactors in the treatment of gaseous waste streams are presented in Chapter 38. Chapter 39 deals with an important development in the strip dispersion technique for actinide recovery/metal separation. Chapter 40 focuses on electrically enhanced membrane separation and catalysis. Chapter 41 contains important case studies on the treatment of effluent in the leather industry. The case studies cover the work carried out at pilot plant level with membrane bioreactors and reverse osmosis. Development in nanofiltration and a case study on the recovery of impurity-free sodium thiocyanate in the acrylic industry are described in Chapter 42. 

Case Studies of Retrofitting Refining Process for Paper Mills... 

This paper is oiganized as follows The section 2 gives definitions of Petri Nets and Colored Petri Nets. It also introduces the structural backward reachability in CPN. The section 3 presents the Linear Logic and its relation with Petri Nets. It is followed, in the section 4, by the details of translation from CPN to mill and the reachability analysis using sequents in Linear Logic.The sections contains a presentation of the case study. The paper ends by the conclusion and an outline of future perspectives. 

This case study describes a behavioral safety program we coordinated as outside consultants at a paper mill in a small New England town over a period of about a year and a half. To understand the challenges involved, it helps to have some understanding of what is involved in the production of such specialty paper products as toweling and decorative napkins. 

Certain Investigators, however, have expressed interest in the matter recently. The possibility that a history of asthma may increase the probability of an acute byssinotic reaction to cotton dust is suggested by a paper by Hamilton et al. ( ). The senior author of this paper had had asthma as a child. Promptly after exposure to the air in a dusty part of a cotton mill he exhibited pronounced shortness of breath with tightness in the chest and accompanying major temporary decreases in FEVi and arterial oxygen tension. The episode is described as "byssinosis". The authors remark It is unlikely that many textile workers with an initial response to cotton dust such as the one described here would remain working in dusty areas." Although the authors state that "It is not possible from the present study to conclude that a prior history of atopy confers sensitivity to cotton dust", the present writers were left with the impression that the authors suspect that such may be the case. 

The contouring of the calender rolls by grinding in order to counteract the natural deflection and the deflection set up by the work being done with rubber stock load is a precision job and in most cases it is done by trial and error method. The nip pressure per inch width of the roll for most rubber compounds has been extensively studied by scientists in the Dunlop Rubber Company [ref Paper "Estimation of the shear deformation exerted by a roll-mill upon a rubber compound" by T.S. Ng, G. Angerer, Dunlop Forschung, Dunlop-Strasse 2, Hanau, Federal Republic of Germany, Presented at the Jahrestagung der... 

For DRIFT studies, a wood wafer, paper sheet, or milled wood sample dispersed in KBr (or KC1) is placed in a cup at the focal point of the concave, ellipsoidal mirror so that the incident light is focused on the sample. The scattered light coming from the sample is collected from the concave mirror and directed by a suitable mirror system to the detector of the FTIR instrument. The pressure used for smoothing the sample has to be adjusted so that reproducible results can be obtained (Yeboah et al. 1984). The contribution of specular reflectance can be diminished by reducing the particle size and by increasing the sample dilution. For powder samples, as indicated above, the diluent is KBr or KCI. Good results are normally obtained with alkali halide powders that contain 1-2% of sample. In certain cases, the sample concentration may be increased up to 10%. 

This work is part of the smart enterprise division in Tumut Visy Pulp and Paper, and addresses the advanced control and operation of the mill. In this context, a robust dynamic model is developed for the recovery boiler, and validated over a wide range of operating conditions. In the steady state case, energy and mass balances were carried out over the different sections of the process. In the dynamic case, initially, heat and mass transfer across the bed are coupled with moisture evaporation, black liquor pyrolysis, char combustion and gasification, gas-phase. The influence of model parameters kinetic constants and operational variables on process dynamics are studied by numerical simulation. The model was developed/implemented in a Visual C++ environment. 

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