The electrolysis required to make PVC is a very energy intensive process. Is its use sustainable?
Most chlorine today is produced by separating the chlorine and sodium ions of a salt brine in an electric field. This process is called electrolysis. One ton of salt (and water) yields around 600 kg of chlorine, 680 kg of sodium hydroxide (caustic soda) and 17 kg of hydrogen.
Electrolysis plants consume a substantial amount of energy but despite this, PVC production uses less overall energy than most alternatives; this is quantified by eco-profile data. Consequently, greenhouse gas emissions related to PVC production are lower as well.
Some nine million tons of chlorine are produced in Western Europe and used in more than half of all chemical activities.
The electrolysis of salt therefore is a basic process to get important raw materials used in the chemical industry. Some 34% of chlorine is used to produce PVC, 23% to produce isocyanates for the production of polyurethanes, chlorine is also used in the production of polycarbonates or silicones and low amounts to keep 98% of Western Europe’s drinking water safe and produce other chemicals. Sodium hydroxide is important for the manufacture of paper, soap and textiles and other applications. Hydrogen is either used chemically or to generate energy.
Since both chlorine and sodium hydroxide are produced in a highly efficient way, they are also a good basis for low cost materials. Products made from them, e.g. PVC-products therefore are also low cost products, a very important point in a sustainability assessment.
In summary, electrolysis yields in the end products requiring relatively low energy and being low cost, an important environmental, economic and social contribution to sustainable development! (for more information on chlorine, see www.eurochlor.org )
Is cadmium still used as a stabiliser?
Council Directive 91/338/EEC of 18 June 1991 limits the use of cadmium compounds in PVC products. Except in a very few applications, placing on the market of products manufactured from plastic materials coloured or stabilised with cadmium is prohibited if the content of cadmium exceeds 0.01% by mass of the plastic material
The use of cadmium in all stabiliser systems placed on the European market has been phased out in March 2001, as part of the initial steps of the Voluntary Commitment (Vinyl 2010). This means that no member of ESPA sells anymore such products in the European Union, Norway and Switzerland, and that EuPC communicates to its members not to use cadmium based stabilisers
How will REACH impact phthalates?
DEHP will most probably be subject to authorisation. On the other hand, DINP and DIDP will not be considered as substances of very high concern, because they are
How much does PVC contribute to the “mountains of plastic waste” problem?
The total amount of municipal waste generated in the European Union was close to 200 million tons in 2000. The amount of construction/demolition waste represents an additional 400 million tons. Plastics waste represented about 20 million tons in total. The amount of PVC waste arising in 2000 was estimated to be less than 3 million tons, hence it represents only 0.5 % of the total amount of waste.
Plastics represent around 9 % by weight of the total amount of Municipal Solid Waste generated in Western Europe. PVC represents 7 % of this plastic waste, hence around 0.6 % of the MSW.
PVC therefore does not contribute significantly to the “mountains of waste”, the more so as PVC products have a comparatively high density and usage of PVC in high volume/weight applications (bottles, other packaging) is limited.
Won’t dumping PVC into landfills pollute soil and ground water?
A study carried out in 1999 by Rostock University on behalf of the European authorities concluded that the long-term behaviour of PVC in landfill does not raise concerns when tested under conditions which simulate actual landfill behaviour. Testing at extreme conditions to accelerate the decomposition yielded questionable results. The PVC industry asked the Universities of Hamburg-Harburg and Linköping to perform tests at temperatures up to levels tested by Rostock.
The main findings were:
All things considered, PVC products do not constitute a substantial impact on the toxicity of landfill leachate. Provided that landfills are operated appropriately and responsibly in accordance with present technical regulations, landfilling of PVC products does not raise environmental concerns.
Are there better possibilities than landfill and incineration?
Landfilling is an unsustainable waste treatment option for all plastics, not only for PVC. A study carried out in 2002-2003 in order to compare different end of life treatment options for PVC-rich waste concluded that all recovery/recycling options are preferable to landfill. PVC, like other thermoplastics, has intrinsic energy, which can be recovered through incineration. The chlorine part ends up in the form of hydrochloric acid, which can be recovered too. Flexible PVC will generally contribute higher energy content than rigid PVC, although even rigid PVC has a calorific value similar to paper. Recovering both HCl and energy significantly increases the eco-efficiency of incineration.
Different types of waste will have different optimal routes for valorisation. Assessing a combination of environmental, logistical, and economic and market considerations will determine the best option. Therefore, the whole range of waste management options should be considered when deciding on the treatment of plastic waste.
|Method||Suitable option for|
|Mechanical Recycling||Sorted, single PVC products|
|Feedstock Recycling||PVC mixed with other plastics|
|Energy Recovery||Non-sortable / contaminated mixed plastics and other solid waste|
Does PVC in the waste stream disturb the recycling of other plastics?
Mechanical recycling of polymers so that they can be used again for high value second life applications is really only possible when you have waste made from that polymer alone. The recycling of any specific polymer will be disturbed by presence of any other polymer. Fortunately, PVC material is very easy to separate from polyolefins (other plastics) by density difference, which makes separation into mono streams for efficient recycling possible. And,if separation is not practical, mixed plastics can be recycled into applications for which the purity is of less importance (e.g. traffic management devices, park benches).
An alternative to ‘Mechanical recycling’ is ‘Feedstock recycling’ which is well suited to the treatment of mixed plastics. The only requirement is that the installation must have a section to separate and recover HCl from the other gases, which is usually the case.
Isn’t PVC difficult to recycle?
PVC is very easy to recycle mechanically (i.e. without destroying the polymer chains). Mechanical recycling is well suited when clean fractions are available in sufficient quantities on a regular basis. PVC can be recycled repeatedly (in laboratory tests more than 8 times); depending on the application, because recycling does not measurably decrease the chain length of its molecules. There are already several purpose-built operations in Western Europe, which recycle pipes, profiles, flooring, and membranes. The West European PVC industry has made clear public commitments to significantly increase mechanical recycling in these applications.
Large quantities of PVC pre-consumer (industrial waste) are being recycled: In 2004, 92 % of the about 760 kt of industrial waste generated in the EU-15 were recycled . Close to 100 kt of PVC post-consumer waste were recycled in 1999. The efforts of Vinyl 2010 are now adding 150 kt based on 2007 figures, and the intention is to grow this to in excess of an extra 200 kt a year by 2010.
The main difficulty for the recycling of post-consumer PVC is in collecting suitable waste at an acceptable cost. This difficulty does not affect PVC alone, but all plastics as well as many other materials.
Next to conventional mechanical recycling, a dissolution process (Vinyloop ®) has been developed to extract PVC from products such as cables, tarpaulins, etc. The recovered product is PVC compound that can be used without further processing and cleaning. The first commercial plant has started up in Italy early 2002. Another one was recently started up in Japan.
Feedstock recycling is an alternative to overcome the limitations of mechanical recycling. Its purpose is to recover a basic chemical element such as carbon and/or chlorine. Extensive trials have also demonstrated the suitability of two commercial plants in Germany to carry out PVC feedstock recycling. Other technologies for PVC feedstock recycling are being developed in Europe and Japan
If we want to save precious fossil fuels, shouldn’t we stop producing PVC which is made from oil?
Oil, gas and coal are non renewable resources and will be eventually exhausted. Connected to their use are also carbon dioxide (CO2) emissions, which create the Greenhouse Effect as most scientists believe. Some organisations therefore ask not to use products made from plastics and substitute them by products made from renewable resources.
Most products from plastics and even more so from PVC are low cost products. In the case of PVC, with only some 0.5 % of the cost one can compensate for 100% of the energy demand (i.e. also for the oil, gas etc. used to produce them) and for 100% of the greenhouse effect related to the production of these products. The compensation can be achieved by investing this 0.5 % in an energy (and at the same time Greenhouse effect) saving activity, e.g. in developing countries.
So one can rightly claim to: “Save oil and Greenhouse effect with low cost products made from oil!”, by only using a small amount of money to compensate for these impacts. This is much more efficient than using higher cost products made from renewable resources.
PVC is in addition a special plastic, since it uses less oil, gas etc. due to its high chlorine content. Besides, this oil can be substituted by renewable resources when the conditions are right; this is practised e.g. by companies producing PVC in India and Brazil dehydrating bio-alcohol from crops such as sugar cane to ethylene; and using this ethylene to produce PVC.
Why could PVC be good for sustainable development (environment, economy, society)?
Since the acceptance of the concept of Sustainable Development (SD) (world conferences of Rio de Janeiro 1992 and others) it became accepted that SD is based on three pillars, namely ecology, economy and society.
The environmental impact of PVC products has been investigated in numerous studies, quantified in many life cycle analyses and compared many times to products made from alternative materials. The latest and most comprehensive study was a Review commissioned by the EU. It showed PVC products to be comparable to alternatives in their environmental impact. The strongest aspects of PVC products are performance and cost; PVC products are amongst the lowest cost products for a given performance (see also Q 2). Low cost products can positively contribute to all areas of SD:
The huge potential impact of low cost products made from PVC can be shown easily: With only 0.5 % of the cost of PVC-products one can compensate the entire energy demand (100%!) and the entire Greenhouse Gas effect (100%!) caused by them. Investing this small amount of money into environmental improvements allows it to create products which are much better in these important environmental categories than all alternatives.
The social aspect of products is not assessed well enough up to now, except for the positive economical/social points mentioned above in this chapter and the health impacts on workers in the PVC industry: After many years of sustained efforts, workers safety has reached a very high standard in the chemical industry altogether compared to other industries.
Why are Life Cycle Assessments (LCA) important?
To truly understand a product’s environmental ‘footprint’, its entire life cycle needs to be evaluated. This is known as LCA. Through this form of assessment environmental effects associated with a product’s manufacture may often be counterbalanced over
time by a reduction in transportation and installation coasts and the benefit of a long, beneficial, low-impact life. For example, emissions associated with PVC window production compared to wooden windows are far outweighed by decades of energy-saving benefits and not having to replace them as quickly or apply preservative paints or chemicals.
Recent life-cycle studies show the health and environmental impacts of PVC building products are comparable to or less than the impacts of most alternatives
Do PVC producers genuinely care about the environment, or are they just meeting minimum legal regulations?
The targets of the PVC producers are certainly more ambitious than just meeting regulatory requirements: The PVC industry in Europe has voluntarily risen to meet the challenge of sustainable development. It has developed an integrated approach to deliver responsible cradle-to-grave management, set out in a 'Voluntary Commitment of the PVC Industry' that was signed in March 2000. This Commitment is now known under the name “Vinyl 2010”.
The Voluntary Commitment builds on principles of the chemical industry's Responsible Care® programme and addresses key issues across the PVC lifecycle. It contains quantifiable targets, with interim deadlines, that will allow the industry to track its progress towards achieving the overall objectives.
The annual Vinyl 2010 progress reports show that the industry has been forging ahead with continuous environmental improvement and resource efficiency through a 'learning by doing' approach, strengthening the partnership within their supply chain. The industry delivers quantifiable results.
More information on www.vinyl2010.org
How does PVC industry demonstrate its long-term commitments?
he PVC industry has a long record of public commitments. It started with commitments towards continuous environmental improvement in manufacturing, as illustrated by the two Charters signed by European PVC producers that establish tough environmental standards for production ahead of legislation. Substantial reductions of industrial emission levels have been achieved as a result.
European PVC industry employers signed in October 2000 a social dialogue charter on issues surrounding the sector's future and their potential social effects on employees.
Through this charter, the PVC industry commits in particular to:
In March 2000, the resin producers, additives producers and converters signed a “Voluntary Commitment of the PVC Industry”. It was further developed and re-issued in October 2001 under the title “Vinyl 2010 - the Voluntary Commitment of the PVC Industry”. It was again updated in May 2006. With this document, the PVC industry has undertaken to implement important actions covering the period 2000 – 2010 and beyond, which will apply to
Progress towards these commitments is documented in the Progress Reports issued each year since 2001. These reports are verified by an independent third party. For more information, consult www.vinyl2010.org
Never before has a voluntary approach been developed through such an open process and covered an entire production chain and all the aspects of sustainable development.
How does the PVC industry see the future?
The PVC industry’s Voluntary Commitment demonstrates the fact that it is serious about the sustainable development of PVC, and that it believes that PVC can make an important contribution to a more sustainable future for society.
In combination with the cost-performance and good properties PVC will remain a material of choice for the specifier and final customer. The improvements of the production processes and the management of waste support this excellent product-performance.
The industry believes that its products have an important role to play in helping improve people’s lives and conserve natural resources in a world that is growing in population, with ever-increasing demands for water, food, shelter, sanitation, energy, health services and economic security.