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This paper mainly discuss the effect of beating on OCC pulp fiber morphology and paper physical Strength. After the treatment with PFI, the beating degree were ranged from 25 ° SR rises from 56 °SR, the fiber morphologies were greatly changed, and appeared splitting and brooming. Physical results showed that beating can improve strength properties of OCC pulp in the proper degree, 46°SR was the best result in this study.

Noise pollution is a workplace hazard which causes loss of hearing, depending on the sound pressure level and duration of exposure. Because duration of exposure is usually uncontrollable, sound absorbers are used to reduce the value of sound pressure level. A common method to reduce noise is to use porous sound absorbers made out of mineral wools or glass fibres. However, these materials pose health risks and are non-recyclable. This project aimed to fabricate a sound absorber using recycled paper which is in the form of egg cartons as an alternative to the abovementioned fibres. Paper fibres posses high fibre porosity and can be manufactured in a manner which the properties can be easily controlled, making them ideal to be made into sound absorbers. Furthermore, they are biodegradable, do not pose health risks and can be manufactured into different shapes easily. Recycled paper was first turned into pulp, blended and poured into moulds. Different amounts of pulp was compressed until the sample size was approximately 20 mm thick and then dried in a furnace dryer at 600C for 12 hours. The samples were tested using a two-microphone, transfer function impedance tubes according to the ISO 10534-2 standard. Its porosity was determined using a modified wash basin method. The results indicate that the optimum panel has an average noise reduction coefficient, (NRC) of 0.50, which qualifies it to be used as a sound absorbing material. It also encounters its maximum value of 0.98 which occurred at the 1575-1675 Hz range. When compared to other materials, recycled paper has similar properties as coir fibre and is quite comparable to other commercial sound absorbers at the same thickness.

The feasibility of pulp and paper mill wastewater sludge as substrates for biogas production was evaluated in labrotory scale. Also the influence of pre-acidification, feeding modes and sludge concentration on anaerobic digestion system were studied.

Paper defects mean that there are some defects in the paper such as hole, emboss, and fold during the paper production, which mainly results from the limitation of technological level. In the past time, artificial visual inspection and off-line checking were often used to detect the paper defects. However, its shortcoming was highlighted along with the improvement of industrial technology level and increasing demand for paper. In order to realize the online detection and markers for paper defects, the project designs the on-line detection system based on line-scan digital camera. Firstly, the principle and detection scheme of the system for the paper defects was presented. Then the overall structure of the system was designed. After that, the hardware circuit of the system was designed using TMS320F2812 as main control chip. It mainly consists of the function of each module and the working process of the system. Finally, the software of the image acquisition system was presented. With the experimental verification, the system has advantages of low cost, high efficiency and strong resistance to interference. The functions and indexes achieved the design requirements.

In paper dryer section of the paper machine, paper dehydration is small, but the steam consumption for the process of dehydration is very large, this steam consumption has a great influence to the total steam consumption of the whole papermaking process. A method optimization of the dryer section based on genetic algorithm is proposed to reduce the dryer section steam consumption, which can reduce the total steam consumption of the papermaking process. After analyzing steam consumption of the whole drying process, the result is that the temperature of dryer section air is the key factor that influences the steam consumption. The model of paper machine dryer section is build with supply air temperature as a variable and steam consumption as the objective function, then using the genetic algorithm to optimize the supply air temperature. Simulation results show that after optimizing air temperature by genetic algorithm steam consumption of papermaking process is further reduced.

In order to realize precise control of the vertical inverting feeding of paper, the paper proposes the scheme to analyse the accuracy. Based on the geometric constraint relations of the feeding device, the position constraint equation of the device is established, together with the speed-acceleration formula; and the relationship between the paper inverting deviation angle and its drop height is obtained using the general equation of dynamics of the horizontal projectile motion as vertical inverting accuracy analysis of the device. The results of the study show that the precise control of the vertical inverting feeding of paper can be realized through the control of the angle.

In this paper a new method is proposed for intelligent sort of battery from waste paper based on Invariant Moments and Fractal Dimension (IMFD). In IMFD, a new distinctive feature that based on the edge contours is extracted to describe the target picture. At first invariant moments technique is used to extract Hus seven moments as the global descriptors from the target image. Then the fractal dimensions are extracted as local invariant descriptors by using Fractal Dimension. At last, a combing descriptor is built according the distinctive feature, which combines the global descriptor and the local descriptor together. The features are highly distinctive, and can be matched with high probability against a large database of features. The practical tests performed in this article show that the proposed method has a significant effect on increasing the stability, the accuracy of classification, and also can effectively against the huge-information during the image processing.

In order to research the relationship between ink permeability and dot gain of different paper, four kinds of coated paper and two kinds of printing paper were chosen. Ink marks method was used to measure ink permeability of four kinds of coated paper and two kinds of common printing paper. After the ink marks were printed on each of the six kinds of paper, the length of them were measured, then the reciprocal of the ink marks length was multiplied by 1000 to obtain the value of the ink permeability. Inkjet printer was also used to print yellow GATF step-wedge simulating offset printing on the six kinds of paper, then using an optical densitometer to measure the dot gain. Conclusion shows that non-coated paper is higher in permeability than coated paper, which results in high percentage of dot gain.

In this paper, we presented an approach to control on the total hardness over the wastewater treatment recycling process for pulp and paper mill. The main problem, however, is the effects of Ca2+ concentration on the recycling treatment process. The experiments were conducted by using coagulation method with reagents of Ca(OH)2 addition alone and Ca(OH)2 +PAC addition respectively to control on total hardness. The samples were collected from the effluent and the influent of the biological treatment tank respectively of the wastewater treatment plant in a pulp and paper mill. The experimental results identified that the optimum reagent addition position was in the effluent of the biological treatment tank. When addition Ca(OH)2 alone, the optimum Ca(OH)2 addition amount was 2g/L, as a result, 70.1% of total hardness was removed ( from 1088.05mg/L down to 325.16mg/L), pH value was from 7.23 to 8.61, and sludge volume ratio was 9.9%. When addition PAC+ Ca(OH)2 , the optimum Ca(OH)2 addition amount was 1g/L, the optimum PAC addition amount was 300mg/L respectively, as a result, 71% of total hardness was removed( from 1088.05mg/L down to 315.25 mg/L), pH value was from 7.23 to 7.66, and sludge volume ratio was 6.5%. The effluent-quality can meet the National Industrial Wastewater Recycling Standard on the total hardness of 450 mg/L requirement. The reagents of Ca(OH)2 +PAC had many advantages over Ca(OH)2 alone , such as less sludge quantity, high density of sludge, small volume of sludge, and less addition of reagents and so on.

Contrasting《Discharge standard of water pollutants for pulp and paper industry》(GB3544-2008) to《Discharge standard of water pollutants for pulp and paper industry》(GB3544-2001), this article educes impact for pulp and paper industry by 《Discharge standard of water pollutants for pulp and paper industry》(GB3544-2008). This article discuss producing technics and dealing with waste water technics of pulp and paper industry, that satisfy GB3544-2008.