Study of Variability of Waste Wood Samples Collected in a Panel Board Industry

Waste wood is becoming an appealing alternative material to virgin wood, and the main drivers are the increased demand for waste wood by the panel industry, the introduction of renewable energy policies, and the waste framework directive. In fact, the use of waste wood as a secondary resource is favored over both landfills and combustion. The best reuse and cascading use of the material are linked to its characteristics. That is why it is important to know the chemical composition and the variation in the properties of such a heterogeneous material. In this article, a sampling study was carried out in a panel board company located in the northern part of Italy. In order to investigate the heterogeneity of waste wood, all samples have been analyzed by near-infrared spectroscopy. Nested analysis of variance and principal component analysis have been used to evaluate the heterogeneity and the variation in sample properties. The approach gives information about how to ensure representative measurements and efficiently describe the variability of the material. The results suggest that it is important to have replicates or at least two subsamples for each lot and then measure each of these with at least 100 scans, in order to get representative measurements and describe the variability of the material. The determination of waste wood composition and variability is the focal point for improving the sorting process and increasing the reuse of waste wood, avoiding expensive landfills and risks for human health and the environment.

Determining the optical stability of printed laboratory substrates with wheat pulp after ageing treatment

The use of recovered paper in the paper and board industry worldwide has increased in the last decade. The recycling process affects several properties of the paper, so recovered pulp needs to be enriched with a certain amount of virgin fibre to increase the strength and quality of the paper, and thus the quality of the print. Since the cellulose-based printing substrates are sensitive to photolytic damage caused by exposure to light and high temperature, the focus of the research was to evaluate the stability of digital UV inkjet prints on laboratory substrates with wheat pulp. Assessment of the optical stability of laboratory substrates and prints made on them after ageing treatment was based on the reflectance spectra measurements before and after artificial ageing. In order to observe the optical changes that occur in cellulose printing substrates, unprinted and digital printed substrates were placed in an artificial ageing equipment SunTEST XLS+ test chamber according to standard ASTM D 6789-02. The test chamber emits visible and near ultraviolet electromagnetic radiation in the range from 290 nm to 800 nm. With the deterioration of the optical stability of unprinted and digital printed substrates, it was observed through the reflectance spectra (R) and the Euclidean colour difference (ΔE00*) that the highest colour degradation of all analyzed samples, occurs in the first 48 hours of artificial ageing. The results of this analysis confirm that the addition of wheat pulp in paper pulp provides better optical stability of unprinted and digital printed laboratory substrates.

Estimation of the PCB Production Process Using a Neural Network

Printed Circuit Boards (PCB) are an integral part of all electronic products, and the production process for printed circuit boards is quite complex. As the life cycle of electronic products becomes shorter and shorter, and the precision and signal bandwidth of electronic products become higher and higher, the manufacturing process of printed circuit boards is further complicated. Therefore, how to pre-evaluate the production difficulty before starting the production will effectively increase the efficiency and quality of printed circuit board production. Gerber file is the most commonly used data format for the printed circuit board industry. This file contains most of the parameters required for the manufacture of printed circuit boards. Therefore, this study uses a neural network to evaluate new PCB products before they are produced through the production parameters that are more influential in the PCB manufacturing process. This makes it possible to evaluate the difficulty and the required production process before the new PCB product is produced. This will be very beneficial for the PCB production schedule, quality control, and cost.

Dispersion of 24-mm staple fibers with foam

In addition to carding and airlaid processes, nonwovens are produced from staple fibers by a wet-laid process. A drawback of this process is the necessity to use very dilute fiber suspensions to avoid fiber entanglement and consequent poor fiber web uniformity. As a result, flow volumes are very high and process speeds are rather low compared to water forming used in the paper and board industry. A promising option for making nonwovens is foam laying. The bubbles in foam keep the fibers apart until the foam is removed, and much higher fiber weight consistencies can be used compared to traditional wet laying. A key challenge in foam forming of nonwovens is to obtain uniform dispersion of the fibers in the foam. In this work, we studied this with 24-mm staple fibers, and analyzed the homogeneity of the obtained foams by making fibrous sheets from them in a laboratory sheet mold. We found that dispersion was highly dependent on the mixing conditions, such as mixing time, foam air content, and fiber weight consistency. Remarkably, excellent fiber disintegration and uniform sheets were obtained without mechanical pre-treatment of staple fibers, with fiber consistencies as high as 0.3%. By comparison, conventional wet-laid processes typically operate with fiber consistencies lower than 0.05%. Thus, at an industrial scale, foam forming promises production of uniform webs from stable fibers with clearly lower water volumes and possibly also higher machine speeds compared to conventional wet-laid forming.

Upscaling of foam forming technology for pilot scale

The need for production cost savings and changes in the global paper and board industry during recent years have been constants. Changes in the global paper and board industry during past years have increased the need for more cost-efficient processes and production technologies. It is known that in paper and board production, foam typically leads to problems in the process rather than improvements in production efficiency. Foam forming technology, where foam is used as a carrier phase and a flowing medium, exploits the properties of dispersive foam. In this study, the possibility of applying foam forming technology to paper applications was investigated using a pilot scale paper forming environment modified for foam forming from conventional water forming. According to the results, the shape of jet-to-wire ratios was the same in both forming methods, but in the case of foam forming, the achieved scale of jet-to-wire ratio and MD/CD-ratio were wider and not behaving sensitively to shear changes in the forming section as a water forming process would. This kind of behavior would be beneficial when upscaling foam technology to the production scale. The dryness results after the forming section indicated the improvement in dewatering, especially when foam density was at the lowest level (i.e., air content was at the highest level). In addition, the dryness results after the pressing section indicated a faster increase in the dryness level as a function of foam density, with all density levels compared to the corresponding water formed sheets. According to the study, the bonding level of water- and foam-laid structures were at the same level when the highest wet pressing value was applied. The results of the study show that the strength loss often associated with foam forming can be compensated for successfully through wet pressing.

Sandwich Panels Bond with Advanced Adhesive Films

Sandwich structures present several advantages, being used in many industries such as the aeronautical industry. In this study, an automated laminating line is employed to manufacture sandwich panels for boards. This work focus on an innovative solution, employing an advanced adhesive film to increase the bonding strength of sandwich structures used for this application. This was used to bond ceramic steel sheets to honeycomb‐cored structures, creating an innovative solution for the board industry. Bending tests were carried to evaluate the performance of the new sandwich solutions and to compare it against a typical one available on the market.

KEBUTUHAN ENERGI PADA PEMBUATAN PAPAN PARTIKEL DARI TANDAN KOSONG KELAPA SAWIT, SERBUK KULIT PINUS DAN AKASIA

Human needs for wood as building materials or furniture continue to increase along with the increase in population, while the availability of wood in the forest is both limited in number and quality. This affects the particle board industry which is increasingly difficult to get good quality solid wood. One alternative to replace wood particles is Oil Palm Empty Bunches which has enormous potential to be used in the engineering field, especially as raw material for making particle boards, by utilizing acacia bark as an adhesive (matrix). To make particle board energy is needed in the manufacturing process. The energy needed in the process of making particle boards is 47,446,211.61 Joules for 25 particle boards or for 1 board for 1,897,848.46 Joules. If converted to Rupiah, the value of one particle board is Rp. 5030. When compared with factory-made prices with a size of 120 cm x 250 cm with a thickness of 1.2 cm at a price of Rp. 90,000, the particle boards that have been made are more expensive than factory-made ones.