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| PAPER and the ENVIRONMENT |
The components of this section are:
| Introduction | |
| Forestry | |
| Bleaching | |
| Recycling | |
| Recycled Papers-Printing Guidelines | |
| Summary | |
| Frequently asked questions | read DHM's Environmental Policy |
| Introduction |
The explosion of ecological awareness amongst the public at large during the late 1980's, led to rapid growth in demand for environmentally friendly papers and boards. What was not generally understood, was that all paper products are environmentally friendly to the extent that they are recyclable, biodegradable, and derived from a renewable natural resource. The real issue, therefore, is the degree of their ecolgogical impact. Consequently, when selecting papers in this context, consideration should be given to the perceived relationship between the following factors:
| a) ECOLOGY : | Which environmental issues ? |
For example; recycled papers cannot be "chlorine free" because the nature of the original processing cannot be identified. Indeed, recycling is not the panacea it seems (see "Recycling" section).
| a) PERFORMANCE : | What functional properties must the paper have ? |
For example; where strength/purity/hygiene factors are important, it is unlikely that a recycled product would be as appropriate as a 'virgin' product.
| a) APPEARANCE : | What are the aesthetic requirements ? |
For example; high whiteness and brightness are difficult to achieve with recycled pulps, particularly the post consumer waste and de-inked varieties, because of the impurities of the fibres they yield.
To assist in product selection with an "ecological" bias, an understanding of the issues surrounding FORESTRY, BLEACHING and RECYCLING would be useful.
An outline of each is presented below.
| Forestry | page top |
The principal constituent of paper is cellulose fibre. Cellulose is widely evident in the natural world in grasses, trees, shrubs and plants such as cotton. Indeed, just a century ago the most common source of papermaking fibre was cotton rags. However, a more reliable, manageable and cost effective source of fibre was required when the paper industry converted to large-scale production in the early 1900's. Forests became the natural choice because they were concentrated, vast and relatively easy to harvest. Self-perpetuation demanded that replanting became an industry in itself, in order to ensure ongoing economies of scale. Against this background the process of "silviculture" (the large scale development of saplings) became commonplace in the major forestry regions of North America and Scandanavia; and latterly, Iberia and South America.
Understandably, environmentalists expressed great concern about increasing deforestation and the pulp & paper industry, as a major timber user, became one target of their criticism. On closer investigation, however, our industry is not quite the culprit it was believed to be. In this context, the following points bear consideration :
a) Theoretically timber is an infinite resource because it is renewable AND sustainable. In fact, there are more trees growing in the Western Hemisphere now, than there were in 1900. It would be disingenuous to suggest that this situation is due solely to environmental concerns, but the fact remains, there are more trees. The real issue is biodiversity, but for trees grown solely to harvest, it is surely legitimate to class them as a crop like any other.
b) For over 100 years the replanting rate for "managed" forests has exceeded the rate of felling by a ratio of 2:1. Indeed, in many regions the average exceeds 3:1. Such cultivation was borne of economic necessity, particularly in Canada and Scandanavia, where forestry is a major export earner. The term ‘managed’ refers to commercially operated forests encompassing felling, planting and rotation. Increasingly these operations invite independent third party NGO’s (non-governmental organisations) to evaluate their practices and processes in order to validate the enterprise in terms of environmental considerations. Again the managing of forests is clearly driven by the economic imperative: bad practice is not only bad for the environment, it is bad for business because it will compromise the long term viability of a forestry company.
c) Only around 12% of the timber harvested is destined for use in pulp & paper manufacture. The largest consumers are the construction and furniture industries. The bulk of the timber destined for conversion into pulp is taken from bi-products from other timber based industries and from forest thinnings. The thinning of forests is essential in order to promote growth of the healthier, stronger trees. Thinnings are less useful for the construction and furniture industries because the tree diameters are relatively small. Large diameter trees are used almost exclusively in construction and furniture manufacture and the bi-products from the sawmills generating the requirements for these industries are ideal for pulp manufacture.
d) The deforestation of tropical rainforests has quite rightly dominated the headlines in recent years. It is vital that people are made aware that due mainly to process unsuitability, tropical hardwoods provide less than 1% of the papermaking fibre consumed in the Western Hemisphere.
e) Fast growing species such as eucalyptus and acacia reach maturity in around 10-12 years in sub-tropical climates and so lend themselves easily to widespread cultivation. Indeed, in some regions a eucalyptus can be felled after just 7 years, whilst its root usually produces up to three "crops". For economic reasons therefore, it was inevitable that eucalyptus would become a major species source for pulp mills. Commercial cultivation of eucalyptus has become a major industry in both Portugal and Spain.
It is of note that one influential school of scientific thought maintains that young trees absorb disproportionately more carbon dioxide than their mature counterparts. To this extent, "managed" forests can be considered to make a positive environmental contribution.
Over the last decade huge strides have been made in establishing independent schemes to verify and ultimately certify and accredit forestry ‘best practice’: essentially evaluating the extent to which a given forest is sustainable and how responsibly it is managed. In 1994 less than ¼million hectares were certified, however by 2004 this figure had risen to almost 200million. Two schemes have widespread credibility amongst NGO’s such a WWF and Friends of the Earth: they are FSC (Forest Stewardship Council) and PEFC (Pan-European Forest Certification Scheme). FSC and PEFC labelling is becoming widespread. However by its very nature, certification of a forestry company is a lengthy process and there is currently insufficient FSC/PEFC certified material to meet demand. There is also considerable confusion because there are around 40 different certification schemes in circulation and this has inevitably caused a degree of political infighting. Despite these ‘teething’ problems, many believe that by the end of the decade the vast majority of pulp used by the European paper industry will be derived from certified forests.
| Bleaching | page top |
Anyone who has left a newspaper exposed to bright sunlight for a prolonged period will realise the disadvantage in using impure fibres to make paper. This "yellowing" is due primarily to a substance called, lignin. It is the blend of cellulose and lignin that gives wood its strength. As the only effective way to remove lignin is to boil woodchips in bleach compounds, the bleaching process is a necessary evil in yielding pulp free of wood impurities (this is why the term "woodfree" was coined decades ago; i.e. 'free of wood impurities').
Because consumers consistently demand ever whiter and brighter papers for documents and stationery, pulp producers have invested heavily in bleaching technology. Originally, their reliance was on chlorine gas, however in recent years it was discovered that the effluent generated by elemental chlorine can promote the development of toxic substances known as DIOXINS. Although, traces of dioxins around pulp mills were typically around only two parts per trillion, and as such well below harmful levels, the industry committed significant investment in alternative bleaching. Two new families have emerged and are already in widespread use, namely: ECF (elemental chlorine free); and TCF (totally chlorine free). Most fine printing and writing papers are now made exclusively from ECF and TCF pulps. To help promote awareness these mnemonics are widely used in association with modern paper products.
| Recycling | page top |
This is a highly emotive topic and is the subject of ongoing worldwide debate.
Unfortunately it was seen as a panacea, but nothing could be further from the truth as the following points serve to demonstrate :
a) The use of the "so-called" recycled logo showing three arrows in a continuous loop has fallen into disrepute. It is now largely meaningless as no accepted definition/requirement underpins its use, and as the logo is in the common domain, nothing can be done to regulate its use. In fact it is often used to denote "recyclable paper". The point is, by its very nature, paper has ALWAYS been recyclable !
b) Even before the emergence of the "recycled debate" in the late 1980's, the UK paper industry depended upon recycled paper for over 50% of its fibre requirements. Indeed, in 2003 66% of the fibre used by the British Paper & Board industry was designated as ‘recovered paper’. So rather than specify the use of recycled papers, consumers could make a far more potent contribution to the environment by ensuring that paper waste is properly segregated, and then directed into "the recycling chain" rather than consign discarded paper to general domestic waste, which invariably ends up as landfill.
c) It is a myth that paper can be recycled indefinitely. After 5 or 6 "recycles" cellulose fibres become inert and essentially useless because they are unable to bond adequately together during papermaking. The "recycling chain" depends upon a constant influx of "new" paper to ensure the resultant pulp actually functions. For the sake of argument, if all consumers switched to "recycled papers" overnight, the supply of usable paper would be exhausted within 12 months.
d) Technically, recycled papers are inferior to their "virgin" counterparts. Colour, strength, stability and a whole host of other properties are typically more difficult to control, because of the variability of the "raw" material.
e) As all domestic and industrial waste can never be completely recycled, we must accept that incineration and landfill have ongoing roles to play. Effective incineration is, in part, an energy source in itself but is entirely dependent on the inclusion of combustible material for it to function as a process. Paper waste therefore has a key part to play here, as it does with landfill where the need for biodegradable constituents is also essential, both in themselves and as catalysts.
Recycled fibres have always been fundamental in the world of paper products. Manilla envelopes are entirely recycled, newsprint relies upon a high recycled content, and cardboard boxes would not exist as we know them if recycled fibres were not widely used and available. Essentially, it would be far more helpful to efficiently recycle paper rather than substitute "virgin" papers with recycled alternatives. Domestically and commercially far more can and should be done to collect, segregate and effectively recycle paper waste. This philosophy would have a far more significant positive impact upon the environment compared to merely specifying recycled paper for brochures, documents and business stationery.
It is fair to say that less energy, fewer chemicals and less sludge is involved when converting recycled paper into manilla envelopes and cardboard than would be the case for the much cleaner and whiter recycled fibres required for the production of recycled business stationery and other "fine" papers.
As a rule of thumb the net benefit of using recycled packaging outweighs that of recycled printing and writing papers. Indeed, an even greater positive impact would accrue if consumers insisted that product packaging was less dependent on petrochemical based plastics, so that biodegradable renewable paper based materials could play an even greater role than they do now.
| Printing Guidelines For Recycled Papers | page top |
Notwithstanding the previous section, the use of recycled papers for printing and writing continues to grow, and the techniques employed in their manufacture continue to improve. However, the inherent inferiority of recycled fibres suggests that extra care be taken when printing/converting the products they yield. The following guidelines were developed with this in mind :
PRE-PRESS
* Leave paper in mill wrappers, at near press room temperature, for at least 24 hours.
* Unwrap paper as close to "press time" as possible.
* Ensure the grain direction of the paper is parallel to the press cylinder axis.
ON-PRESS
* Recycled papers tend to have a rougher surface than their conventional counterparts, therefore a greater "nip" may be required to achieve "bottoming-out".
* Expect the surface pick resistance to be lower and use LOW TACK inks where possible.
* For many recycled papers, ink absorbency is higher than would normally expected. So to minimize dot-gain, high pigment strength inks are preferred.
* Because recycled papers often have inferior dimensional stability, extra care is needed for multi-pass jobs.
* Ideally, soft faced compressible blankets should be employed when printing recycled papers.
POST-PRESS
* Keep stack heights to a minimum to limit set-off and encourage drying.
* Always protect stacks with moisture resistant covers as soon after printing as possible.
* Always provide longer than average drying time when planning the job.
| Summary | page top |
Whilst ALL papers and boards are essentially environmentally friendly specific products are available to address particular ecological issues. The choice of product, however, must not only reflect the required environmental credentials but also the properties required of it in terms of appearance AND performance.
Clearly, compromises have to be made in the selection process, and the attendant implications MUST be made clear to the interested parties.
As the knowledge of the impact paper has on its environment becomes more sophisticated, single issue choices will become less relevant. Ultimately, the ecological impact of a paper product from "cradle-to-grave" will become the main driver in the selection process, and to this end, the industry is developing ECO-LABELLING standards to assist in informing the participants in the chain from specification through conversion and use to eventual disposal of the product.
| Frequently asked questions |
Q: Does using recycled paper save trees ?
Rather than use whole mature trees, the paper industry is dependent upon bi-products such as thinnings and saw mill waste. So all other things being equal, roughly the same number of whole mature trees would be felled whether or not recycled papers were specified.
Q: If we recycle more would less pulp be required ?
Paper making fibre can only be recycled 5 or 6 times before it becomes inert and useless as regards papermaking. This means a steady influx of ‘new’ paper is absolutely essential. However we could utilise even more recycled fibre if as a society we forced a reduction in the use of petrochemical products for product packaging. So theoretically there is plenty of latent demand for recycled fibre for packaging.
Q: Can we help save tropical rainforests by using less paper ?
Tropical hardwoods are not really suitable for papermaking and less than 1% of the fibre used to make paper in Western Europe comes from such species. Rainforests suffer primarily from illegal logging and clear cutting (to make way for agriculture and cattle farming).
Q: You often read that a forest the size of a large city is used to produce a bestselling book. Surely there must be some truth in that ?
On the basis that if the book had not been printed there would be more trees on the planet, the assertion is absolutely false. Replanting rates exceed the felling rate by 2:1 and pulp is primarily produced from timber and forestry bi-products not from whole mature trees.
Q: Don’t some web sites claim that one tree is needed to produce 12,500 sheets of A4 80gsm ?
All sorts of claims are made in order to support one vested interest or another – in this case presumably the proponent is implying that by using 12,500 sheets less a tree would have been saved; this is a misnomer! Essentially parts rather than whole trees are converted into pulp. The point is the tree would have been felled for the primary user anyway before the remnants became available to the pulp mill; and on average the tree would have been replaced by at least two saplings. Going further, much of the copier paper produced today is eucalyptus based, in which case the root can yield up to two further trees before it is dug up and replaced.
Q: How much energy would we save if we used more recycled paper instead of ‘new’ paper?
We need ‘new’ paper in order to make recycled paper viable because after 5 or 6 recycles the fibre becomes inert and useless for papermakers. Also a lot more energy is required to make ‘clean’ recycled pulp for printing and writing paper, than is needed to make pulp suitable for brown packaging and envelopes. So we should be more concerned about collecting and segregating waste and then employing the least energy necessary to re-use it. Going further, if we then switched (say) 20% of the packaging currently made from petrochemical products into recycled paper products the positive environmental impact would be huge.
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