No such thing as waste
There is no such thing as garbage - only wasted resources.
All carbon-based waste is a potential source of energy, through biogas, waste to oil, gasification or turning it into briquettes to burn in an improved cook stove or heater. Waste vegetable oil can be used as fuel for diesel vehicles directly, although it is more viscous than regular diesel and may damage engines. Biodiesel is a a fuel derived from filtering and refining used vegetable oil, and can be used as safe and effective source of energy with comparatively fewer CO2 emissions than regular diesel fuel.
Sewage be can a source of nutrients, which are lost when it is simply treated as a disposal problem. When this is done society loses on socioeconomic opportunity that it could otherwise benefit greatly from. After the energy is extracted with a biogas digester, the sludge can be used (with proper precautions) in agriculture. Composting toilets are another solution, which use drastically less water that conventional sewage systems and produce a greater bulk of rich compost compared to the biogas digester, but do not produce energy.
Municipal waste is typically a mess of all kinds of resources:
- Food waste that can be composted. This requires education (starting in schools) and a cultural shift.
- Plastic, glass and metal that cannot be recycled, due to soiling, or being the wrong type.
- Plastics of the wrong type which cannot be recycled; there are processes for converting such materials into second-grade material to make useful products.please expand
- Miscellaneous items, e.g. items soiled with food.
- There are also goods that contain many useful nutrients that are contaminated or otherwise tied up so as to inhibit their effective utilization. A common example of this household carpets. Here large concentrations of natural fibers are bonded with toxic glues and/or mixed with non-biodegradable synthetic fibers.
- One technique to remedy this problem is known as Product Stewardship. This involves the responsibly of a product's disposal, including the associated disposal cost, being put on the producer instead of the consumer. This is incentive to the producer to design products that can broken down in a manner that is cost effective, efficient, and more environmentally conscious.
- In future it may be practical to use paper and plastic items soiled with food in a waste to energy incinerator (SWERF - Solid Waste Energy Recycling Facility).
Industrial ecology is a practice of no waste in industry - every output is used in some way, rather than being allowed to become waste.
- Waste incineration is a processing method which allows for the energy contained within a waste product to be extracted and used. Incineration also allows for the total mass of solid waste to be reduced. This process involves the ignition of waste which is than allowed to burn, fueling a steam generator creating electricity. The gasses released from this process are then filtered to prevent contamination of toxic waste into the environment.
- Currently Sweden is importing waste from neighboring countries to fuel their incinerators. This action has been actively protested against by Greenpeace, in the belief that the filters do not remove dioxin, which is known to be carcinogenic in humans.
- Waste for Life, a loosely joined network of scientists, engineers, educators, designers, and cooperatives working together to develop poverty-reducing solutions to specific ecological problems.
- In future we can expect the use of bio-plastics, which can be more safely recycled, composted or used in a waste to energy process.
- Can the householder can tell what is suitable for recycling and what isn't? A guide to household recycling, with pictures and authoritative information, would be very helpful.[Suggested project]