Urban food waste composting.

摘要

In this thesis, a study was undertaken on the premise that the world population living in urban centers is expected to increase from 3.8 billion to 5.2 billion, from 2005 to 2025, representing 54% and 65% of total world population, respectively. The urban population (UP) growth will produce remarkable amounts of urban food waste (UFW) that will add more pressure on already overloaded municipal solid waste (MSW) management systems of cities. This problem is more serious in countries experiencing major economic growth such as China where UP is expected to increase from 44% to 66% of the total country population, from 1995 to 2025. Asia produces the largest amount of UFW, which is expected to increase from 251 million ton to 418 million ton (45% to 53% of total world UFW) from 1995 to 2025. On site treatment of UFW along with a limited movement of world population from rural to urban areas are suggested to reduce pressure on MS W management system for the upcoming decades.;In this thesis, a project was also undertaken to develop compost recipes for urban center such as downtown Montreal. Monthly (June to August) average residential FW production was found to 0.61 (+/-0.13) kg capita-1 day-1 and that of a restaurant was found to be 0.56 (+/-0.23) kg customer-1 day-1. From trial tests, the best compost recipes mixed 8.9 kg, 8.6 kg and 7.8 kg of UFW for every kg of wheat straw, hay and wood shaving, on a wet mass basis. However, quantity and characteristics of FW vary from one month to another; therefore, regular adjustment of compost recipe is recommended. When using wood shavings as bulking agent, it is strongly recommended to correct the acid pH.