Packaging & laminates Aims – To understand environmental issues associated with paper & board packaging.

Environmental issues of paper & board use in packaging Paper and board are produced primarily from hard and softwoods. Wood is made up of cellulose fibres bound together by lignin. To produce paper, these fibres must be separated to form a mass of individual fibres called wood pulp. Softwood fibres are longer, offering greater strength; hardwood fibres are shorter, offering a smoother, opaque finish. Wood pulp is produced by one of three methods: mechanical, chemical or waste pulping.

Environmental issues of paper & board use in packaging Toxic Pollution Many toxic chemicals are used in paper making, especially toxic solvents and chlorine compounds used to bleach and remove the, lignin from pulp. Many pulp and paper mills have made reductions in chemical use over the years, but these benefits may be countered by increased production. Air Pollution Pulp and paper mills are major sources of air pollutants, such as carbon dioxide. These gases contribute to the depletion of the ozone layer, global warming, acid rain and respiratory problems in the local area.

Environmental issues of paper & board use in packaging Water and energy consumption Paper making is energy-intensive, using large amounts of electricity. It also uses a great deal of water from local supplies, which can cause problems such as increased sedimentation, increased water temperature, a reduction in the number of wildlife species in local habitats, possible concentration of toxic material and lowering of water tables.

Environmental issues of paper & board use in packaging Solid Waste Paper fibres can only be recycled a limited number of times before they become too short or weak to make high-quality paper. The broken, low-quality fibres are separated out to become waste sludge filling large areas of landfill space each year. Some companies may burn their sludge in incinerators. Deforestation Worldwide, enormous areas of virgin forest are being felled for paper pulp production, contributing to the destruction of the world’s forests or deforestation. Many UK paper mills import their pulp, some of which may come from endangered forests.

Environmental issues of paper & board use in packaging Possible Solutions Mechanical pulping is arguably the least environmentally damaging process for producing virgin wood pulp, and has the advantage of producing a high pulp yield compared to other processes. Newsprint quality, mechanically-pulped paper contains few additives, can be recycled up to four times and is adequate for many purposes for which chemically pulped products are currently used. One solution would be greater use of recycled fibre pulp rather than virgin pulp. The UK currently imports large quantities of virgin pulp, so needs to expand its recycling industry as an alternative. Using alternative fibres, such as hemp and straw, can reduce pressure on forests, and have great potential for being produced in the UK.

Environmental issues of paper & board use in packaging Practice Questions 1.Why is recycled pulp used for newspapers? Explain your answer. 2.Why would virgin pulp be used to make a glossy fashion magazine? Explain your answer.

Packaging Laminates A polyethylene, aluminium foil and paperboard packaging laminate combines the characteristics of all three materials into a single package. Developed by Tetra Pak in the 1950s, this innovation has changed the way food is packaged and distributed around the world. Tetra Pak’s strength is in the area of hygienic processing and packaging of drinks. When packaging laminate is combined with ultra-high-temperature processing (UHT), products can be packaged and stored under room temperature conditions for up to a year. This allows for perishable goods to be saved and distributed over greater distances.

Packaging Laminates

Task- Create a model of a section of Tetra Pak using layers of materials. Label the layers & what they do. Layer (out to in) MaterialReason for use 1PolyethyleneExternal layer, protects against outside moisture, glossy finish. 2PaperboardProvides shape and stiffness. Good print surface. 3PolyethyleneHelps bond the paperboard to the aluminium. 4Aluminium Foil Provides a good barrier against air and light (which can damage the contents). 5Polyethylenehelps bond the internal layer with the aluminium foil. 6PolyethyleneInternal layer in contact with the drink. Seals in the liquid.

Packaging Laminates Practice Question (5 marks) Q. Explain how a packaging laminate such as a Tetra Pak carton keeps the liquid inside fresh? Tip - Before you answer the question ask yourself... What do I know about packaging laminates? And Which things are relevant?