Technological aspects

4.1.1 Supply chain for HDD production

An overview of the supply chain for home and fabric care products, including HDDs, is shown in Figure 8. Manufacturers of HDDs (formulators/blenders such as Procter & Gamble, Unilever and Henkel) acquire ingredients such as surfactants from speciality manufacturers and then blend these to produce HDDs.

Figure 8: Supply chain for home and fabric care products

The raw materials used for the production of detergent ingredients are obtained either from oleochemical sources or petrochemical sources. Oleochemical raw materials are derived from plant and animal fats; these include coconut oil, tallow, palm kernel oil and palm oil.81 _{These raw materials are often referred to as renewable raw materials.}

Petrochemical raw materials are derived from crude oil or natural gas; these materials are often termed synthetic. According to the American Cleaning Institute, there is no inherent environmental advantage to using surfactants from one source over the other and there are environmental trade-offs associated with both oleochemical and petrochemical sources.82

Companies active in the European market for detergent speciality ingredients include Clariant, Rhodia, Solvay, Rohm & Hass, Cognis, Croda, Dow Corning, Elementis, Alco

81

Palm kernel oil, coconut oil, and palm oil are three of the few highly saturated vegetable fats; these oils give the name to the 16-carbon saturated fatty acid palmitic acid that they contain. Splitting of oils and fats by hydrolysis, or under basic conditions saponification, yields fatty acids, with glycerin (glycerol) as a byproduct. The split-off fatty acids are a mixture ranging from C4 to C18, depending on the type of

oil/fat. The palm, palm kernel and coconut cultivation has been criticized for impacts on the natural environment, including deforestation, loss of natural habitats. In particular, the cultivation of palm has threatened critically endangered species such as the orangutan and Sumatran tiger and increased GHG emissions. Many palm oil plantations are built on top of existing peat bogs, and clearing the land for palm oil cultivation may contribute to GHG emissions. Source: Wikipedia

82 _{Sustainability resources from the American Cleaning Institute, available from:}

Chemical and BASF, amongst others. Within the home and fabric care ingredients sector, speciality surfactants hold the largest market share in Europe.83

4.1.2 Description of the HDD production processes

The first step of HDD detergent production is to select the ingredients. This is done according to several criteria which will typically include cost, sustainability, human health, environmental safety and performance. Detergent manufacturers use different approaches to ensure that their products have the least impact on the environment and human health. One example of such an approach is the Greenlist™ process developed by SC Johnson, which scores ingredients by their impact on the environment and human health. Using the process, a final product score is obtained which takes into consideration the environmental classifications of both chemical and packaging constituents.

The manufacturing process employed for HDD products in general consists of mixing and pumping the ingredients into mixing vessels. The exact process employed will depend on the manufacturer and the format of the final product. Liquid detergents are produced either in a batch process or a continuous process. The batch process is the simplest: ingredients are introduced to an agitated tank, and additional mixing or heating can be provided through a recirculation loop. In comparison, continuous processes are more sophisticated and better suited to large-scale operations. In a continuous process both dry and liquid ingredients are added and then blended using in-line mixers. The final manufacturing process for HDDs is packaging and typically involves plastic bottles.

A more detailed explanation of the production process of the detergents and the chemistry involved can be found in Annex VIII.

4.1.3 HDD detergents ingredients

HDDs are expected to clean all types of soil from dishware, to have copious long lasting foam, to be mild to hands and to have a pleasant fragrance84 _{and are mainly composed}

of surfactants, preservatives, and additives. More information on detergent ingredients can be found in Annex I. HDDs are primarily a mixture of surfactants dispersed in water and these are used to remove and emulsify fats and aid with wetting. Commonly used anionic surfactants include alcohol ethoxylates such as LAS, alkane sulfonates and alkypolyglycosides.83 _{HDDs must be safe and not damaging to the environment and}

therefore environmental parameters such as biodegradability, aquatic toxicity and bioaccumulation need to be taken into account. Further, they should be non-sensitizing and non-irritating. Further detail on specific detergent ingredients and their environmental performance will be provided in the technical report.

4.1.4 User behaviour

The consumer behaviour and dishwashing techniques throughout Europe have been studied among others by Prof. Dr. R. Stamminger and colleagues. Stamminger et al.85

found that an important reason for not having a dishwasher at home is that there is not enough room in the kitchen. Other reasons include the number of people living in a household, and the performance and consumption values of automatic dishwashing.

83 _{Henkel (2011) The world of fragrances; how washing and cleaning can affect the senses. Available at: http://www.henkel.com/henkel-} headlines/news-2011-20111024-the-world-of-fragrances-34010.htm

84

Handbook of Detergents, Part F: Production, Surfactant Science Series Volume 142, Uri Zoller and Paul Sosis, CRC Press, 2009.

85 _{Stamminger R, A Elschenbroich, B Rummler, G Broil, 2007. Washing-up Behaviour and Techniques in Europe. Hauswirtschaft und}

Nearly everybody has their ‘own way’ of manual dishwashing. Many variations and combinations of processes can be observed, ranging from a series of four ‘baths’ for each item to be washed (i.e. soaking, preliminary cleaning, cleaning, rinsing), to the use of continuously running hot water for about 30 % of the study group. The level of soiling and the number of items to be cleaned also influenced dishwashing behaviour.

The dishwashing behaviour of individuals was found to be surprisingly constant and not likely to be a matter of coincidence.87 _{Consumer behaviour and dishwashing techniques}

greatly affect the amount of resources needed, i.e. water, energy, time, detergent.85

Nevertheless, none of these resources showed a dominant influence on the cleaning performance individually. Therefore, differences in cleaning performance can be attributed to differences in dishwashing techniques, such as clever water management or the amount of mechanical power applied.

Fuss et al.86 _{formulated best practice tips and studied whether they can be used to save}

resources by affecting behavioural changes. The researchers focused on common household conditions, such as large amounts of dishes, and observed a reduction in the use of resources (around 60 % less water, 70 % less energy, and 30 % less detergent) when the best practice tips were applied. A study by Stamminger and colleagues87

showed that the average water consumption increases if the load to be cleaned is divided into smaller portions, from on average 103 litres for twelve place settings in one go to more than 121 litres for six times two place settings.

Consumers’ attitude towards best practice tips is generally positive.86 _{Although some}

concerns exist about their exact application in everyday life, the tips are generally highly accepted.