Environmental risk of waste and its management - Environmental Deterioration and Contamination: Problems and their Management - page 145

Disposal:

- Landfill;

- Incineration without energy recovery.

General environmental protection principles of precaution and sustainability, tech-
nical feasibility and economic viability, protection of resources as well as of the overall
environmental and human health, economic and social impacts should also be taken
into account when the waste management option is selected.
Production of chemicals from waste is one of the main goals of green chemistry.
Natural building blocks of trees, plants and food waste can be utilized in their original
form (recovering them by simple extraction) or after modification by further chemical
or biological catalyses, such as fermentation.
Food waste by definition is composed of raw or cooked food and includes materials
discarded before, during or after food preparation, in the process of manufacturing,
distribution, retail or food service, and includes materials such as vegetable peelings,
meat trimmings, and spoiled or excess ingredients or prepared food. Food waste can
be either edible or inedible.
Food waste valorization is the most up-to-date topic, given that food waste may
be a sustainable source of countless biologically active and otherwise beneficial com-
pounds. Europe started with a study in 2010 (Food waste across EU 27) by assessing
the causes of food waste, the amounts and the existing initiatives as well as environ-
mental and economic impacts. Arancon et al. (2013) summarized the advances on
biowaste, including food waste valorization strategies, with several examples from all
over the world.
US EPA Food waste recovery hierarchy (2013) shows the priority of the utilization
of food scraps:

- Source reduction

- Feed hungry people

- Feed animals

- Industrial uses

- Composting

- Landfill, incineration.

Natural components of food wastes for utilization as material or chemicals are:
pectin, lignin, haemicellulose, cellulose, starch, collagen, chitosan, waxes, pigments,
proteins, amino acids, phenols and sugars, vitamins and other biologically active
components.
Products from waste biomass are materials, chemicals and energy-carriers: liq-
uid fuels, fuel gas, bio-solvents, plastics, e.g. PVC replacement by biopolymers and
lactate-based polymers, bulk chemicals, fine chemicals, oils, fibres, bio-adhesives,
bio-surfactants, natural chelating agents, hydrogels, cosmetic waxes, natural dyes,
composite materials for construction and furniture, etc.
Orange peel is a good example for utilization using complex green chemistry. 50%
of orange juice is accompanied by 50% of waste. About 50 million tonnes of waste
are produced in a year in the Americas, in China, India and Africa. The peel may