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How we are trying to
“Stop Soil Wasting Away”
13th
June 2014
A Case Study – a Flexigester in Malawi
by
Dr John Mullett and Lynn McGoff
Content of presentation
SOWTech will present a case study of new equipment which is designed to make returning human and animal waste back to the soil both safe and affordable Loss of soil fertility is threatening food security in the global south. Chemical fertilisers alone will not be the long term solution.To grow food we need fertile soils. The difference between fertile soil and dirt is organic matter and its associated “bugs”The return of waste to the soil is the only way in which we will stop soil fertility being lost
SOWTech = Sustainable OneWorld Technologies
A community interest company founded to share the problem and opportunity of organic waste treatment in low-income countriesWe have experience and expertise gained in working in the organic waste treatment field over the last 30 years
Designed and built Composting and Anaerobic Digestion projects
ranging from 5 – 40,000 t/a Project experience worldwide including many
counties in Europe, Ghana, Malawi, India and Thailand.
We also have a track record of innovative and value engineering development
enclosed composting, low visual impact AD, ozone based odour control
What does SOWTech do
We design and develop equipment in partnership with others for the treatment of organic waste and the production of fertiliser and renewable energy in low income countriesWe have developed a digester which can process animal, human and vegetable wastesIts unique features are “flat-pack design” for easy transportation and rapid deployment The unit cost of the item will be low enough for widespread application
What is Anaerobic Digestion
The natural process which occurs when organic wastes break down in the absence of air.Methane and Carbon dioxide gas (Biogas) are generated in this process. The plant material changes into a nutrient rich natural fertiliser. The natural fertiliser returns nutrient and organic matter to soil.The process of decomposition reduces the number of pathogens in the material to make the reuse of the waste safer.The biogas can be used as a renewable fuel.
Case Study: Namisu Orphanage, Malawi
Objective: To demonstrate the potential of
a Flexigester for emergency sanitation applications, such as flood relief and refugee camps
Sponsor: International Federation of the
Red Cross & Red CrescentLocation:
Orphanage near Blantyre Malawi, funded by Aquaid Lifeline
Photo taken beginning of April – 2 months after installationFlexigester inflated as it is producing biogasNow receiving human waste from the latrine block, animal waste and waste cooking water
Note the inflated transportable gas bag in the background
Added nutrients means better yields
The usual crop produced locally – no fertiliser
The crop which can be achieved with fertiliser
Sustainable Soil Management
Wherever soil is used for food production, there is a net loss of nutrients and organic matter from the soilChemical fertiliser can replace the plant nutrients, but they do not replace the organic matterWithout organic matter in soils, they lack biomass and are unable to retain nutrients and moisture for plants to useDeclining levels of soil organic matter is not restricted to the global south, but deforestation for fuel, lack of organic fertiliser use, and more intensive land use is generating a problemThis is exacerbated by climate change related increases in heavy rainfall, erosion and unpredictable growing seasons
Why chemical fertilisers will not solve the problem
Those who grow most of the food, which supports the population in emerging economies, cannot afford to buy enough chemical fertilisers now. Subsistence farming, which is 80% of agricultural production in Africa, does not generate the cash needed to buy fertiliser. The chemical fertilisers are not going to get cheaper in the future. The relative costs of chemical fertilisers will continue to rise because:
Nitrogen fertiliser is made from fossil fuel gas Phosphates are mined and demand is predicted to outstrip supply
with significant price rises expected.Fertiliser in Africa can be between 5 to 6 times more expensive than Europe due to transport costs, import taxes, and lack of economies of scale.Central government subsidies in emerging economies are short term and usually unsustainable political expedients
So what is the answer
We must find ways to return the sources of plant nutrients and soil conditioning materials back to the land used by farmers in emerging economiesThis will be through “fertiliser factories” which harness local wastes resources and turn them into soil supporting inputs.If we do not nurture all the worlds soils through better waste management we will be guilty of wasting the very soil itself....
So what are we seeking to achieve
To develop the Flexigester as a fertiliser factory to enable communities to capture and treat organic wastes in a safe and hygienic way To make the technology affordableTo gain widespread distribution and applicationTo drive towards new products and processes which enhance the ability of low income farmers to maximise production of food in a sustainable way
Fertile soils puts food on plates
“We need to feed the soil... if we expect it to feed the people” JAJM
Thank you for your attention
Dr John Mullett
077 026 79191