Griffiths K.R.,University of Bath |
Hicks B.J.,University of Bristol |
Keogh P.S.,University of Bath |
Shires D.,Smithers Pira
Mechanical Systems and Signal Processing | Year: 2016
In general, vehicle vibration is non-stationary and has a non-Gaussian probability distribution; yet existing testing methods for packaging design employ Gaussian distributions to represent vibration induced by road profiles. This frequently results in over-testing and/or over-design of the packaging to meet a specification and correspondingly leads to wasteful packaging and product waste, which represent $15bn per year in the USA and €3bn per year in the EU. The purpose of the paper is to enable a measured non-stationary acceleration signal to be replaced by a constructed signal that includes as far as possible any non-stationary characteristics from the original signal. The constructed signal consists of a concatenation of decomposed shorter duration signals, each having its own kurtosis level. Wavelet analysis is used for the decomposition process into inner and outlier signal components. The constructed signal has a similar PSD to the original signal, without incurring excessive acceleration levels. This allows an improved and more representative simulated input signal to be generated that can be used on the current generation of shaker tables. The wavelet decomposition method is also demonstrated experimentally through two correlation studies. It is shown that significant improvements over current international standards for packaging testing are achievable; hence the potential for more efficient packaging system design is possible. © 2016 The Authors.
Ouadi M.,Aston University |
Brammer J.G.,Aston University |
Yang Y.,Aston University |
Hornung A.,Aston University |
Kay M.,Smithers Pira
Journal of Analytical and Applied Pyrolysis | Year: 2013
De-inking sludge is a waste product generated from secondary fibre paper mills who manufacture recycled paper into new paper sheets; it refers directly to the solid residues which evolve during the de-inking stage of the paper pulping process. The current practice for the disposal of this waste is either by land-spreading, land-filling or incineration which are unsustainable. This work has explored the intermediate pyrolysis of pre-conditioned de-inking sludge pellets in a recently patented 20 kg/h intermediate pyrolysis reactor (The Pyroformer). The reactor is essentially two co-axial screws which are configured in such a way as to circulate solids within the reactor and thus facilitate in the cracking of tars. The potential application of using the volatile organic vapours and permanent gases evolved would be to generate both combined heat and power (CHP) located at paper making sites. The results show that de-inking sludge could be successfully pyrolysed and the organic vapours produced were composed of a mixture of aromatic hydrocarbons, phenolic compounds and some fatty acid methyl esters as detected by liquid GC-MS. The calorific value of the oil after condensing was between 36 and 37 MJ/kg and the liquid fuel properties were also determined, permanent gases were detected by a GC-TCD and were composed of approximately 24% CO, 6% CH4 and 70% CO2 (v/v%). The solid residue from pyrolysis also contained a small residual calorific value, and was largely composed of mainly calcium based inert metal oxides. The application of applying intermediate pyrolysis to de-inking sludge for both CHP production and waste reduction is in principle a feasible technology which could be applied at secondary fibre paper mills. © 2013 Elsevier B.V. All rights reserved.
Moore G.,Smithers Pira
Paper360 | Year: 2012
Declines in the use of paper in many printing and writing applications will result in reduced availability of some recovered paper grades. Globalization of the world economy has increased the trade in recovered paper. China and other countries within Asia will continue to import recovered fiber as domestic paper and board production continues to develop and expand. The potential for increasing paper collection and use exists in both developing and developed countries. Recovery of waste paper and board continues to attract political and social attention in Europe. In contrast, paper for packaging applications has grown with improvements in overall economic performance, but also through the rise of environmental concerns which are favoring paper over plastic based packaging. Recycled fiber has been an integral part of papermaking for many years. The material is a globally traded commodity with recycled fiber-rich countries developing important export businesses around its trade.