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natural recycling vs human generated waste
On a yearly basis a human produces roughly 500 liters of urine and 50 liters of feces. These two products contain enough nutrients to grow most of the plants that this person needs as food. But instead of utilizing these 550 liters as a resource, we mix it with roughly 15,000 liters of water, and all goes down the drain. Before it reaches the sewage plant, if there is one, this slurry gets mixed with hundreds of pollutants along the way.
The conventional sewage plant rarely retains or destroys all bacterial and viral contaminants, it produces a large amount of sludge generally unfit for agriculture, and it causes severe pollution in freshwater and seawater ecosystems. This end-of-pipe solution recycles nothing. It takes valuable resources and transforms them into pollutants. As fertilizer prices rise throughout the world, and as water becomes an increasingly scarce commodity, this unsustainable approach makes no sense.
Modern agriculture gets the nitrogen it needs from ammonia-producing plants that utilize fossil fuels such as natural gas, LPG or petroleum naphtha as a source of hydrogen. This energy-intensive process dumps carbon dioxide into the atmosphere, it consumes a finite hydrocarbon resource, and it is not sustainable.
Modern agriculture gets the phosphorous it needs from phosphorous-bearing rocks. But these reserves are rapidly dwindling and increasingly contaminated with pollutants such as cadmium. In as little as 25 years apatite reserves may no longer be economically exploitable and massive world-wide starvation is predicted to follow.
If we are serious about achieving sustainability in this regard, our first, and perhaps most important duty, lies in not mixing urine with feces. Within the human body these two wastes are produced and stored separately, they are excreted separately, and afterwards they should be contained and processed separately. A double-outlet toilet, one for urine and the other for feces, is all that is needed.
The feces receptacle, except for the lid, is exactly the same device used for the mesophilic storage of household biowaste, and if carefully utilized and cleaned out, the one bin could receive all bio-waste from the household, including human feces. Such a toilet is ideal, especially in an rural setting where a toilet in many cases is nothing more than a platform above a catfish pond or a hole in the ground. Quite often people in a rural setting do not even use a toilet of any kind. There are enormous environmental and health problems in Vietnam associated with outdoor urination and defecation.
This toilet can be manufactured as a pedestal toilet or a squatting toilet. Since, in the case of a squatting toilet, the feces receptacle has to bear the entire weight of a person, it is best constructed out of brick.
The feces storage bin is inhabited by BSF larvae within about 20 days after its construction. BSF larvae eat human feces within an hour or two after it is introduced. This is a powerful factor in eliminating odor.
Biochar can also be added to the storage bin from time to time to further eliminate odor. Since biochar captures ammonia in gaseous form, biochar can also be added to the urine receptacle of this toilet. There is also the concept of a biochar urinal, a concept that will be explained more fully in the conclusion.
Urine could be collected from urine-diverting toilets, diluted and directly applied to certain crops as a source of NPK. Simple soil insertion techniques prevent the volatilization of ammonia. Urine, or a mixture of biochar and urine, can be used as an important source of nitrogen in thermophilic composting operations.
duckweedHowever, if the transport of urine is not feasible, there is another approach, and it allows for the complete processing of urine on site. This approach involves a tiny aquatic plant that is one of the fastest growing plants on earth. As it floats on the surface of the water, it extracts NPK and other nutrients from water through all surfaces of its leaf. Given sufficient sunlight, it can reduce quantities of NPK in water down to almost undetectable levels. This amazing plant, found throughout the world, is called duckweed.
Under optimal conditions, certain duckweed can double in mass within a period of only 16 hours. Its protein content is one of the highest in the plant kingdom (sometimes as high as 45%). It is also rich in beta carotene, xanthophylls, as well as vitamins A and B. It contains very little fiber and indigestible matter.
pondIn this approach, urine would be flushed from the urine-diverting toilet into a small duckweed pond located near the toilet. Since duckweed covers the entire surface of the pond, very little ammonia would volatilize and give rise to unpleasant smells. The duckweed harvested each day makes a wonderful feed for chickens, pigs, fish and, of course, ducks. Duckweed can be dried, ensiled, blanched or fed fresh.
The logic of the sustainable processing of human waste has certain parallels with the logic of the sustainable processing of residential bio-waste. Both demand separation at source. Both employ mesophilic bins, BSF and red worms. Both refuse to define themselves as independent large-scale waste disposal activities, and both are intimately connected to the sustainable production of food, feed and fertilizer. Human waste, like pig waste, is far too nutrient-rich for the production of fuel by means of methanogens.
We talk a lot about sustainability, but we will never achieve true sustainability until we learn to give back to nature in a closed loop everything that she needs to sustain us. Giving back to nature all of the nutrients within our own waste is perhaps our first and most important duty as citizens of planet Earth.
Recycling Waste
With the increasing human population the needs for the people also increases. But the point of concern is that are there enough natural resources to service all your needs. What if these resources finish, this is one thing we need to ponder upon. We need to start recycling waste to converse our natural resources. Recycling is simply the process of reusing the items from which utility can still be derived. It is important to recycle waste so that you can at least converse some of our natural resources for our generations to come.
Many products such as paper, cardboards, and cups come from trees. In fact trees are our natural assets, you can converse trees by recycling the paper products we can minimize the number of trees cut down a year. This is one form of waste recycling. One should understand and know the importance of recycling waste materials. One simple benefit of recycling is it saves our resources. It will be wise to reuse metal item as metal reserves may be depleting. You can sold your wore out metal items for recycling. As mentioned earlier, recycling of waste papers can save our forests.
Recycling waste not only save our natural resources but also help save energy. By simply recycling an item or making a basic fix to it, we can we save all the energy that would have been consumed in the process of making it. The same example can be taken with plastic items. A large amount of energy can be saved by simply reusing the plastic items. To recycle waste is to simply reduce pollution. By recycling plastic material we can reduce air pollution as well as water pollution. Plastic factories produced large amount of smoke when producing plastic material at the same time if we don t have proper waste disposal system those waste emissions will cause water pollution. Recycling waste in a way helps reduce pollution.
In simple words, recycling or recycling waste is essential to both natural environment and humans. To sum up, recycling minimizes the need for raw materials so that the rainforests can be preserved. Great amounts of energy are used when making products from raw materials. Recycling requires much less energy and therefore helps to preserve natural resources. One needs to know the importance of recycling at the same time being earth friendly can help our planet a better place to live in.
Solid waste can be hazardous or non-hazardous and is generated by many sources including residential, commercial, institutional and industrial. Municipal solid waste is regulated by the provinces and territories and managed by the waste management industry under contract to municipal or regional authorities. In contrast, solid waste from industrial processes can be handled directly by the producer and disposed of either on land or in water.
Municipal solid waste
Used packaging, food scraps, old computers and newspapers generated by business and household activities are all examples of municipal solid waste. Residential waste is generated by households and can be picked up by the municipality, private waste management companies or transported by households to collection, recycling and disposal facilities. Non-residential waste includes non-hazardous waste generated by industrial, commercial and institutional sources as well as waste generated by construction and demolition activities.
Municipal solid waste can be managed through disposal in landfills or incinerators or can be diverted from disposal through recycling or composting. Waste diversion can reduce the demand for energy and new resources by re-using materials that have already been produced (for example, aluminum, glass, plastics and paper). As a result, it can also reduce greenhouse gas emissions.
From 2002 to 2008, municipal solid waste disposal increased slightly from 769 kilograms to 777 kilograms per capita. During the same time period, solid waste diversion increased from 212 kilograms to 254 kilograms per capita (see Textbox: Waste Management Industry Survey: Coverage).
Solid waste can impact the environment in various ways, depending on how it is managed. For example, waste disposal may contribute to soil and water contamination, while methane gas produced at landfills contributes to greenhouse gas emissions (see Textbox: Landfills and incineration).
Waste Management Industry Survey: Coverage
Unless otherwise indicated, Section 3.1 Municipal solid waste uses data from the Waste Management Industry Survey: Business and Government Sectors. 1
The estimates presented in this section refer only to waste that is processed by firms or local governments that are part of the waste management industry as classified by the North American Industry Classification System (NAICS). Waste that bypasses the waste management industry is not included in survey coverage.
For example, estimates do not include waste managed on-site by companies or households. While the majority of residential waste is handled by municipalities or private businesses, a significant quantity of non-residential waste is managed on-site by industrial generators or is transported directly to secondary processors such as pulp and paper mills.
The estimates also do not include materials that were processed for reuse and resale (for example, wholesaling of scrap metal or used clothing) or materials that were collected through deposit-return systems (for example, food and beverage containers and tires).
Agricultural waste is not covered by these surveys. This waste is typically managed on-farm or by specialized firms that are not classified as part of the waste management industry under NAICS.
The waste management industry in Canada
A range of services are provided by the waste management industry: collection and transportation of waste and materials for disposal and diversion (recycling and composting); operation of non-hazardous and hazardous waste disposal facilities; operation of transfer stations; operation of recycling and composting facilities; and treatment of hazardous waste.
Waste management services are provided by one of two sources: public bodies, such as local governments or waste management boards or commissions, and private firms that enter into contracts with local governments or businesses to provide waste management services. In 2008, there were 31,344 full-time workers employed in the waste management industry, 81% working in the business sector and the remainder employed by government.
Total current expenditures on solid waste management by local governments were $2.6 billion in 2008, a $1.1 billion increase over 2002. Of this, 42% went to collection and transportation, while operation of disposal facilities accounted for 18% and tipping fees accounted for 14% (Chart 3.1).
Disposal
With few exceptions, materials thrown in the garbage are destined for waste disposal facilities where they are either landfilled or incinerated (see Textbox: Landfills and incineration and Textbox: Energy from waste).
In 2008, Canadians sent 25,871,310 tonnes of solid waste for disposal (777 kilograms per capita), a 7% increase over 2002 (Table 3.1). At a provincial level, the largest increases were seen in Alberta (39%) and New Brunswick (16%). Nova Scotia was the only province that experienced a decrease in waste disposal (-9%).
Residential solid waste made up a third of total waste disposal in 2008, although this proportion varied by province. In Newfoundland and Labrador, residential sources accounted for 53% of waste disposal, compared to 24% in Alberta.
From 2002 to 2008, residential solid waste disposal remained nearly stable, increasing by 1%, from 8,446,766 tonnes to 8,536,891 tonnes (Table 3.1). However, on a per capita basis, it decreased 5% to 256 kilograms. Per capita residential solid waste disposal was highest in Newfoundland and Labrador (429 kilograms) and lowest in Nova Scotia (158 kilograms) in 2008 (Chart 3.2).
Landfills and incineration
Landfills are used as the primary means for the disposal of waste materials in Canada. The main environmental concerns related to landfills are leachate and landfill gas.
As liquid moves through the landfill, it picks up a variety of toxic and polluting components in large or trace amounts forming leachate, which can potentially contaminate ground and surface water. Sanitary landfills control the types and quantities of incoming waste and use liners and leachate collection and treatment systems to prevent water and soil contamination.
Landfill gas is formed as organic material decomposes in landfills. This gas is composed mainly of methane, a greenhouse gas (GHG) 21 times more potent than carbon dioxide (CO2) in terms of its global warming potential. 2 It also includes CO2, small amounts of nitrogen and oxygen, and trace amounts of a wide range of other gases. Concerns about landfill gas include fires, explosions, vegetation damage and unpleasant odours. 3 In 2009, emissions of methane from landfills accounted for 22% of national methane emissions and 3% of total GHG emissions. 4 Landfill gas can be captured and flared, converting the methane to CO2 and reducing odour, or used to generate electricity or provide fuel substitutes. 5 In 2009, 349 kilotonnes of methane were captured and combusted, half of which was used in energy applications while the rest was flared. 6
Incineration includes a range of practices, from low-tech open burning to controlled combustion processes using mass burn systems and other types of modern incinerators using pollution control devices that burn waste at temperatures between 900 and 1,100 C. 7 Less than 5% of municipal solid waste disposal goes to incineration in Canada. 8
One of the benefits of incineration is the reduction of the amount of waste for disposal. However, incineration creates gaseous waste and ash and can contribute to air pollution. In 2009, municipal incineration released 677 tonnes of particulate matter (PM) (0.004% of total emissions of PM), 350 tonnes of sulphur oxides (SOx) (0.02% of total emissions of SOx), 1,364 tonnes of nitrogen oxides (NOx) (0.06% of total emissions of NOx), 602 tonnes of volatile organic compounds (VOCs) (0.002% of total emissions of VOCs), 1,330 tonnes of carbon monoxide (CO) (0.01% of total emissions of CO) and 19 tonnes of ammonia (NH3) (0.004% of total emissions of NH3) into the atmosphere. 9
Dioxins and furans, which are persistent organic pollutants, are potential contaminants from incineration. These toxic, bioaccumulative chemicals can result from incomplete combustion due to inadequate technology or improper incinerator operation. 10
Mercury is another potential bioaccumulative contaminant that can be emitted when items containing mercury are placed into the incinerator. Limiting the amount of mercury in waste as well as the use of specialized air pollution control equipment reduces releases of mercury. 11
Non-residential waste made up two-thirds of total solid waste disposal in 2008. From 2002 to 2008, non-residential solid waste disposal increased by 11%, from 15,634,606 tonnes to 17,334,419 tonnes (Table 3.1). The largest increases were seen in Alberta (52%) and Newfoundland and Labrador (21%).
Energy from waste
Energy from waste facilities are highly efficient power plants that produce heat and electricity using municipal solid waste as fuel, thereby replacing the energy produced by conventional power plants that use fossil fuels, such as coal, oil, or natural gas.
Of the seven municipal incineration plants located across Canada, five generate energy, burning approximately 763,000 tonnes of municipal solid waste. Approximately 3% of disposed waste was incinerated at energy from waste facilities in 2006. 12
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