Assesing alternatives

Regulation. There’s no avoiding it when it comes to assessing the market for drycleaning solvents in 2005.

For this year alone will see Europe’s drycleaning businesses conform to the European Union’s Solvent Emissions Directive (SED). In the USA, the year began with a radio station incorrectly suggesting that all Californian drycleaners would be required to switch completely from the principal drycleaning solvent, perchloroethylene or perc, to an alternative process in the coming years.

Although this was an error on the part of the radio station, is it perhaps the shape of things to come? Although environmental departments in certain USA states (North Carolina, for example) concluded that there is no credible evidence to associate perc with cancer in humans, some states, most notably California, regard perc as a carcinogen and continue to put numerous rules and fees in place that restrict its use.

Possibly the most significant step was the decision in December 2002 by the governing board of California’s South Coast Air Quality Management District to phase out perc machines in the USA’s second most populated urban area by 2020. SCAQMD is the air pollution control agency for Orange County and the urban portions of Los Angeles, Riverside and San Bernardino counties, with a total population of 16 million people.

This rule will only affect 2,200 dry cleaners in the SCAQMD area only; but its wider importance is that other air-quality agencies in the USA are waiting for a precedent.

While an early date for the completion of the phase-out date was dropped, drycleaners are now subject to strict limits on the amount of perc they can emit, and must also implement new technologies that reduce perc emissions. The requirements were agreed with several drycleaning associations and an industry group made up of the USA manufacturers of perc: Dow Chemical, PPG Industries and Vulcan Materials.

So why is there so much legislative pressure on the industry to switch from perc to an alternative cleaning system? The question of perc’s carcinogenicity has been a subject of much study and debate over the past 25 years. The USA Environmental Protection Agency (EPA) currently classifies perc as a “possible” carcinogen but has tried to move it up to the more serious “probably” category.

The Halogenated Solvents Industry Alliance (HSIA), which represents manufacturers, importers and users of perc, has sponsored research in this field. A Nordic study to assess whether workers exposed to perc have an increased risk of cancer has now been completed. The study is not due to be published in full until later this year (2005), but the association said it did not appear to raise concern regarding perc exposure.

One thing is certain – drycleaners know that tougher restrictions now apply to the use of perc; but are they prepared to meet the new requirements?

Concern about perc’s effects upon the environment and health has led to a search for alternative ways to clean clothing. These alternatives, supported by a new generation of equipment, are:

? silicon-based

? hydrocarbon-based

? carbon dioxide (CO2)

? wetcleaning.

In the USA, the South Coast Air Quality Management District remains the only regulatory body to seek a total ban on perc. As part of the phasing-out process, it introduced a grant programme to assist drycleaners with implementing alternative technologies.

In a report last December, the SCAQMD’s board was told that the number of drycleaning plants in the four-county region using non-perc alternatives has tripled from around 100 in 2002 to more than 300 at present. The installations have included 235 hydrocarbon, 44 GreenEarth, 31 wetcleaning and 2 liquid CO2.

Of the original USA$2million made available for drycleaning grants in 2002, some USA$1.4 million has now been spent on grant awards to the end of 2004. The grants to individual cleaners range from USA$5,000 to USA$20,000, depending on the technology.

Applications for financial assistance in the two years have included 180 hydrocarbon machines, nine for GreenEarth, 41 for wetcleaning and two for liquid CO2.

Solvents emissions

In Europe, drycleaning is an activity that is within the scope of the European Union’s Solvent Emissions Directive (1999/13/EC) and complete compliance with this is required by 2007.The SED is a European Council Directive relating to “the limitation of emissions of volatile organic compounds (VOCs) due to the use of organic solvents in certain activities and installations” and adopted by the European Commission on 11 March, 1999.

Drycleaners must meet a total emission limit of 20g of solvent emitted per kg of product cleaned and dried or implement a solvent reduction plan. Compliance is required immediately for new installations, and by 31 October 2007 for existing installations. (They must have a full year’s records by this date). Although the SED Regulations came into force in the UK on 20 January 2004, existing installations (drycleaners which came into operation before 1 April 2001) will not be affected until 31 October 2006.

New drycleaners (businesses which came into operation on or after 1 April 2001) should already have made an application for a PPC permit by 20 May, 2004.

A survey of drycleaning machine numbers has been carried out through user associations across the EU. CINET, the International Committee of Textile Care, has assessed the situation for 2000, and the projected situation for 2007.

With the help of trade associations, machine manufacturers and solvent producers and distributors, emission estimates have been made based on each of the four types of unit:

?Type I: drycleaning machine with water-cooling but without activated carbon filter

?Type II: drycleaning machine with refrigeration cooling and activated carbon filter

? Type III: closed drycleaning machine with refrigeration cooling without exhaust air

? Type IV: closed drycleaning machine with refrigeration cooling and activated carbon.

Emissions of perc in 2000 are estimated at 44,734t/yr. Cinet says conversion to modern low emission drycleaning machines will result in a maximum emission of 8,550t/yr under the SED by 2007, a reduction of 83% from the 50,805t emission identified in the EU’s 1994 risk assessment for drycleaning use. Cinet’s forecast assumes all machines convert to Type IV before 31 October 2007.

Future for perc

Perc has proved its value to the international drycleaning industry, according to Hans Norbert Adams, research and development at Dow Chemical and consultant to the European Chlorinated Solvent Association (ECSA).

But despite its position as the leading all-purpose solvent choice for drycleaners, he acknowledges that perc has, and continues to be, the subject of scientific debate and regulatory restrictions.

He believes Dow has established that an industry solvent can change to conform to new regulations. He is in no doubt about the cleaning properties of perc, since its high KB value makes it ideal for dissolving virtually all organic stains such as oils, grease, fat and waxes, while its low viscosity/low surface tension permits rapid penetration of fibres.

Research has led to the development of modern cleaning systems and the adoption of operational best practice, he says.

“There has been a marked improvement in efficiency as modern drycleaning systems have developed. This change has to a great extent been driven by regulations and prompted much closer co-operation between the solvent producers and the manufacturers of the new generation of drycleaning machines; in effect a partnership for effective risk management,” says Adams.

Dow has developed the Safechem solution for the European market, which combines its Safe-Tainer System with the latest generation hermetically-sealed cleaning equipment. Safechem has 4,500 customers in Europe operating 15,500 Safe-Tainer state-of-the-art closed loop delivery systems.

The system reduces the risk during internal transport and storage and complies with all legal requirements regulating use of chlorinated solvents.

“Dow will continue to promote the use of closed loop delivery systems and co-operate with all stakeholders along the supply chain to ensure that perc is used in an environmentally safe manner,” says Adams.

In the UK, Tom Elliott, managing director of Alex Reid, acknowledges that several countries restrict perc and believes it is inevitable that this will influence the UK market eventually – particularly problems such as ground contamination where landlords and surveyors are taking a close interest.

“Alex Reid has been looking for many years for a solvent that gives drycleaners a practical alternative to perc. That is not to say we believed perc to be under significant immediate threat.”

“We carried out extensive research into GreenEarth prior to the launch last summer, and it soon became clear that the process has many advantages. These include the flexibility to handle a wider range of fabrics, easier finishing, a reduction in the claims experienced by drycleaners, no ground water contamination and improved working conditions for staff.

“Whilst GreenEarth has multiple benefits, it’s important to stress this does not necessarily mean that perc is bad. It’s all a matter of choice and the fact that the industry has a choice should be valued by all – the industry should not be based on one solvent alone.”

Siloxanes

The solvent used in GreenEarth drycleaning, commonly known as D5, is a cyclosiloxane. Silicones or Siloxanes are synthetically manufactured polymers that consist mainly of the elements silicon, hydrogen, carbon and oxygen (Si; H; C; O).

Different companies manufacture D5, according to Dr Manfred Seiter of Chemische Fabrik Kreussler & Co of Wiesbaden, Germany. These include Dow Corning, Bayer GE Silicones and Wacker, with brand names like Dow Corning 245 Fluid, SB 32, Pure Green and GreenEarth solvent.

The GreenEarth Company was founded 11 March 1999 in Delaware as a joint venture between USA drycleaners (GreenEarth Cleaning) and GE-Silicones. The GreenEarth solvent and drycleaning process is patented (EP 1 084 289 April 3 2002 GreenEarth Cleaning). A license fee has to be paid per year and per machine.

The advantages of D5 for drycleaning are that it is non-toxic and non-hazardous, says Seiter.

In Europe, cyclosiloxanes are subject to the EEC 1999/13/EG VOC-regulation; in the USA, cyclosiloxanes are classified as inorganic materials, so they are not subject to the VOC regulation (EPA Clean Air Act).

D5 has been widely used for many years as an ingredient in personal care products, such as roll-on deodorants and anti-perspirants, shampoos and hair conditioners. To further enhance the understanding of the safety of siloxanes in consumer and industrial applications, siloxane manufacturers have initiated a multi-year, USA$30million research programme called the Siloxane Research Programme (SRP).

At present (February 2005) the USA Environmental Protection Agency is awaiting the final results of the two-year chronic toxicity and carcinogenicity study on D5, delayed until this spring (2005). In April 2003 it received the preliminary results of a cancer study on D5 in rodents, which indicated that there may be a cancer hazard associated with it. But the results of the research are dismissed by the Silicones Environmental, Health & Safety Council (SEHSC) as “specific to the rats” and having “no relevance to human health”.

In the UK, the Johnson Service Group acquired Alex Reid in late 2003 as a vehicle for operating the GreenEarth licensing system. “D5 is one of the most extensively studied materials used in consumer and industrial applications,” says a spokesman. “Decades of in-depth research on D5 indicate that the product is safe when used as intended. Johnsons conducts all its drycleaning processes in accordance with best occupational health practices, ensuring that all exposures to solvent are maintained well below any statutory or recommended limits. We remain fully confident that D5 continues to be safe in its controlled use, whilst offering the many benefits associated with GreenEarth drycleaning.”

Hydrocarbons

Today’s generation of hydrocarbons are safe, effective, and provide a low-cost alternative to other solvent systems, according to Nancy Eilerts, the new product and technology director of Chevron Phillips. Before the introduction of perc in drycleaning, the majority of drycleaners used petroleum solvents. However, these solvents were highly toxic – containing a mixture of benzene and other carcinogens – and were also extremely flammable.

These newer hydrocarbons have a lower flashpoint and so are not as susceptible to explosions, says Eilerts. New equipment for petroleum solvents has been developed to further lower the danger of explosions (High Flash: where flash exceeds 60C (140F) and meets Class IIIA requirements; Low Flash: where flash exceeds 37.8C (100F) and meets Class II requirements).

Most hydrocarbon drycleaning solvents are isoparaffins: they are widely used in waterless hand cleaner and cosmetics and food processing plants as direct additives to food (sugar, wine, vinegar manufacture and cleaning vegetables for example), as well as solvents.

The hydrocarbon supplied by Chevron Phillips is EcoSolv drycleaning fluid. This is classified as a high flash Class IIIA isoparaffin fluid. It can be mixed with other isoparaffin drycleaning solvents (for example, DF-2000) without draining the machine.

Cleaners using the system can expect to clean up to 40,000lbs of clothes per drum of solvent.

Hydrocarbon solvents are safe for fabrics as they minimise dye and soil transfer, says Eilerts. They are odourless,,and residual solvent in shoulder pads and cuffs will dry at room temperature.

Carbon dioxide

In the mid-1990s, development began in the USA on a cleaning method based on liquid carbon dioxide.

If CO2 gas is liquefied under pressure (as in a fire extinguisher) it becomes an ideal solvent for drycleaning all types of textile. Combined with a specially developed detergent, without water, the procedure is odourless and leaves no residue in the treated textile.

After cleaning, the CO2 is returned to its original gaseous form so that a drying procedure is no longer necessary as it is with perc or hydrocarbons.

The Hangers Cleaners franchise was brought from the USA to Sweden in the autumn of 2003 by AGA/Linde, holder of a European licence for this type of CO2 cleaning. The franchise was extended to the Netherlands, where five stores opened in 2004.