Ample evidence is available in the qualified literature on the diversion potential of biodegradables. Composting, digestion with or without methane capture, reuse as animal feed and even incineration are well-documented
technologies. Although the technical aspects of diversion are well attended to, diversion rates achieved in practice are low. The research described here studies the life cycle of basic food items in order to discover the reasons for the low landfill diversion rates of this material. The result points to management failures at key points of the cycle as basic obstacles to higher diversion rates.

The study looks into commercialization procedures of fruit and vegetables before consumption, into consumption proper and into after-consumption disposal procedures for food scraps in the Brazilian context. Results are
surprising. Before consumption, the rate of lost fruit and vegetables stands at 13 weight percent of the total quantity commercialized. During consumption by residents, the waste rate of food amounts to 28 weight percent of all collected household garbage. In the after-consumption lap of the cycle, biodegradables represent 72 weight percent of all household garbage collected by official means in a typical Brazilian town.

These numbers produced by the study are impressive and clearly identify landfill diversion of biodegradables as a management problem. The authors faced the challenge and experimented with original proactive administrative
procedures which led to more surprising results. The occurrence of wasted fruit and vegetables at the wholesaler and retailer levels is identified.

Remedies are proposed and tested to reduce the waste rate by at least 50%. In the after-consumption lap, the notion of divided garbage collection is developed and applied to test communities. It is shown that biodegradables
may be collected separately from the rest of household waste. This results in a diversion potential of 100% for biodegradables alone and 84 weight percent for all collected household waste. Models are presented that show the material flow in the life cycle of biodegradables with emphasis on management actions. The study produces a formal proposal to municipal administrations to avoid the need for biodegradable landfill through implementation of divided collection and composting or digestion of all organic material in household waste. Thus consumption and disposal bio-systems are combined in order to achieve the landfill diversion.

Keywords: 
material flow analysis, integrated bio-systems, food commercialization losses, household waste, divided collection, landfill diversion.

Marilda dos Reis Calçado, M.Sc.
Chemical Engineer, Environmental Consultant in Brazil

Biologist, Environmental consultant, Graduate Student in Environmental Management. Federal University, Uberlandia, Brazil