Waste consists of unavoidable losses of input material occurring in cleaning, trials, color changes, repair and maintenance, and other non-continuous operations. Other waste sources include packaging materials, cleaning materials, out-of-shelf-life finished goods, and maintenance goods, such as oils and other utilities.
In total, Sika generated around 112,000 tons of waste (previous year: 84,000 tons), which accounts for around 1.6% of the total volume handled by Sika (previous year: 2.1%).
Approximately three-quarters of the waste is non-hazardous. The “reuse” category covers waste which finds a secondary, lower-grade use or is reprocessed, e.g. through metal recycling. Sika manages waste disposal through management systems to ISO 14001, which regulates the flow of materials and local documentation. ISO 14001 is in place at all production sites.
1) Total weight of non-hazardous waste:
- Non-hazardous: 66,000 tons (previous year: 66,000 tons)
- Landfill: 45,000 tons (previous year: 29,000 tons)
- Incineration: 9,000 tons (previous year: 8,000 tons)
- Reuse/Recycle: 38,000 tons (previous year: 29,000 tons)
2) Total weight of hazardous waste
- Hazardous: 20,000 tons (previous year: 18,000 tons)
- Incineration: 20,000 tons (previous year: 18,000 tons)
With an increased production volume, the company generated some 112,000 tons of waste (previous year: 84,000 tons). This corresponds to 14.1 kilograms of waste per ton sold (previous year: 18.1 kilograms per ton sold), or a decrease of 22%. This drop in waste generation is mainly due to the lower waste intensity of the acquired Parex company. Overall, Sika was able to reduce the amount of waste per ton sold by putting in place activities such as optimized production planning, streamlined production process layout, and the reuse of production waste. In addition, water from cleaning processes (tanks, bulk delivery trucks, and gas scrubbers) was reused. Furthermore, filter dust from dosing and bagging stations was recycled into similar products in mortar production. Innovative warehouse management was also implemented to reduce the quantity of expired products. With regard to circular economy initiatives, Sika worked on a project to recycle waste from polyurethane adhesive for use as a raw material in membrane production.
Large amounts of waste are minerals or sand from sand drying, oversized or undersized sieve residues or dust from air-filters and the cleaning of mortar facilities. Amounts vary widely from year to year, resulting in deviations which are difficult to predict and manage. Sika has started to find commercial applications for some materials, e.g. aggregates for roadworks, allowing these inert materials to be taken off the waste balance. Furthermore, the company strives to reduce the generation of contaminated water, and to reduce the volume on the premises per low pressure distillation.
Sika strives to increase the durability of its products. In the USA, for example, the company has long operated a successful recycling system for end-of-life roofing membranes, with the recycled material being used in the manufacture of new membranes. Under their ISO 14001 management systems, the local companies are obliged to find a compliant, cost-effective, and efficient method of disposal and to maintain the necessary documentation on waste transfer to the disposal endpoint.