Cement, Energy and Environment

Packaging products that conform to the 'compostable' criteria of the relevant standard are suitable for composting (the tests simulate industrial scale composting conditions) and those that conform to its anaerobic criteria are suitable for that method of organic recovery. Intelligent waste management In line with the European Directive for Waste Management, the new bag is transformed into valuable humus through the industrial composting process, and used again for enriching soil. In order to fully benefit from this cycle, Terra Bag needs to be integrated into the waste management system for biodegradable waste already in place in many countries. Should a system need to be set up at a construction site, the setup cost of such a system is estimated at only half of the disposal cost without such waste separation. Construction waste in France In France alone, 35 000 t of waste generated at construction sites is made up of cement packaging (cement bags and protective covers). This waste falls under the category of non-dangerous waste, which should be reused, recycled or composted. With 765 industrial composting facilities spread throughout France, the recuperation of the bags is reasonable and easy. Reduced environmental impact The use of renewable raw materials in the production of paper and bioplastics helps to slow the depletion of non– renewable resources and reduces waste production and environmental pollution. Life– cycle analyses of bioplastics show that C0 2 emissions can be up to 20 per cent lower than those for commodity polymers, when properly disposed of in industrial composting facilities. Optimized for filler's needs Compared with pure paper bags, Terra Bag provides enhanced product protection - the biofilm presenting a moisture protection that improves the shelf-life of the contents. The bag has been optimized thanks to various tests carried out by application engineers at the bag application centre (BAC) and directly at customers' sites. The bag solution presents no constraints in filling speed; therefore, fillers do not need to settle for a compromise but can enjoy their usual production speed while reducing the environmental impact of their product packaging. Confirmed compostability and biodegradability Standard EN 13432 requires compliance of several aspects: • Biodegradability: this test consists of measuring the actual metabolic, microbial conversion, under composting conditions of the packaging sample into water, C0 2 and new cell biomass. Tested in a controlled environment (humidity, oxygen, temperature , C02 production), at least 90 per cent of the organic material must be converted into C02 within six months. Non– biodegradable components must not exceed a limit of 1 per cent each and 5 per cent in total (ink, glue). • Disintegration: the packaging sample is mixed with organic waste and maintained under test scale composting conditions for 12 weeks. After 12 weeks composting and subsequent sifting through a 2 mm sieve, no more than 10 per cent residue of the original mass may remain. • Compostability: practical test of compostability in an industrial composting facility. No negative influence on the composting process is permitted. • Ecotoxicity: compost application: examination of the effect of resultant compost on plant growth (agronomic test), ecotoxicity test. Biopolymers Biopolymers are made from a renewable resource or are biodegradable or both at the same time. The biopolymers made from a renewable source, but which are not biodegradable are, for example, most cellulose derivates, sugar based PE/PVC, ethanol based PE/PVC etc. Biopolymers that are biodegradable but made from a fossil resource are, for example, PCL, PBAT various polyesters, PBS, etc . The biofilm used in Terra Bag meets both criteria of biopolymers. These are, for example, starch-based thermoplastic, starch-based complexes, cellulose acetate, poly lactide acid (PLA), polyhydroyalkanoates (PHA), etc. The biomass comes from crops such as sugar beet potatoes or wheat, then classified as non-food crops. Many types of packaging can be made from biopolymers: food trays, blown starch pellets for shipping fragile goods or films like the one used in Terra Bag. Courtesy: Bulk Materials Handling Review (World Cement), 2010, Pp 57-60. 29