Széchenyi István Egyetem Environmental impacts and possibility for sustainable development of human excreta Dr. habil. Aniko ZSENI 1, Judit NAGY 2 Széchenyi István University, Győr, Hungary 1: Department of Environmental Engineering 2: Department of Applied Mechanics 3rd International Conference on Environmental and Economic Impact on Sustainable Development 8-10 June 2016, Valencia, Spain WIT Conferences Zseni, A. - Nagy, J.

Széchenyi István Egyetem Content of presentation Short history Environmental impacts of flush toilet based infrastructure: example of Hungary –Demand of natural resources (water demand, energy demand) –Pollution load of domestic sewage (water pollution, GHG emission) Human excreta as a possibility for sustainable development –Nutrient content of human excreta –Environmental impacts of composting of human excreta Conclusion Zseni, A. - Nagy, J.

Széchenyi István Egyetem Short history Collection and removal of human excreta dates back 4-5 thousands of years Various methods and techniques were used according to historical times and places Using human excreta in the past and in the present for agricultural or industrial purposes (e.g. gunpowder from urine) was known, but not widespread everywhere and at all times Zseni, A. - Nagy, J.

Széchenyi István Egyetem Spread of flush toilets 1788, Joseph Bramah: registered the invention of flush toilet tank connection of flush toilets to the drinking water and sewer system became widespread pollution of water bodies  „end of pipe” solutions  more and more advanced technologies of waste water treatment during wwt: the organic matter content is broken down and converted to nitrate, inorganic phosphate, CH 4, CO 2  water, air, sludge However, we must replace missing nutrients to soils artificially, which lead to the exploitation of soils in the long run Human excreta = waste which must be clear away as fast as possible by water Zseni, A. - Nagy, J.

Széchenyi István Egyetem Nitrate pollution of underground water bodies Flush toilets Inorganic N and P in the sludge get to the soil Organic matter of human excreta gets to water as inorganic N and P Nutrients of human excreta are lost Water demand  Wasting of pure water Household-generated greywater must be treated like blackwater, unnecessarily Eutrophication There is no way of humus forming from the organic matter content of the human excreta Burning and digestion of sludge: organic matter of human excreta become CO 2, CH 4 and inorganic N (  to soil) Inorganic N and P accelerate the decomposition of hum us Energy and cost demand of sewage drainage and waste water treatments are high (  CO 2 ) (  reduce of energy resources) Changes in natural water cycle SZE: Zseni, A. – Nagy, J.

Széchenyi István Egyetem Environmental impacts of flush toilet based infrastructure: example of Hungary Water demand: –Households: 95%: drinking water pipes system, 77%: sewer system –water consumption of households: 326 million m 3 /year, (90.5 l/day/person) –Sewage water of households: 250 million m 3 /year –94% of drinking water from underground water  water from wwt plans to surface water Energy demand: investigated wwt plans in Hungary, based on Domokos Selected wwt plans in Hungary capacity (PE) energy consumption (kWh/PE/year) wwt plan capacity (PE) energy consumption (kWh/PE/year) over Budapest, CWTP Győr Tét Jánossomorja Tiszaalpár Zseni, A. - Nagy, J.

Széchenyi István Egyetem wwt plants in Hungary (total: 832 plants) Waste water load in 2013 (PE) Estimated specific energy consumption (kWh/PE/year) Estimated total energy consumption (MWh/year) 0-2 thousand PE , thousand PE , thousand PE , thousand PE , Over 150 thousand PE , Altogether The estimated and calculated data of energy consumption of Hungarian public wastewater treatment plants In comparison: –Energy produced by solar panels in Hungary: 154 thousand MWh/year –Energy produced by wind power in Hungary: 700 thousand MWh/year Zseni, A. - Nagy, J.

Széchenyi István Egyetem Pollution load of domestic sewage: Changing human excreta to waste urea  NH 3  NH 4 NO 3 organic P  inorganic phosphate organic compounds  inorganic N and P, CH 4, CO 2 Zseni, A. - Nagy, J.

Széchenyi István Egyetem Pollution load of domestic sewage Water pollution: –From households: 44 thousand tons of N (4.4 kg/person/year) 10 thousand tons of P (1 kg/person/year) is removed –After wwt: 15 thousand tons of N (1.5 kg/person/year) 3.5 thousand tons of P (0.35 kg/person/year) GHG emission: –Biological treatment (oxidation of organic compounds) –Sludge treatment (CH 4  CO 2 ) –GHG emission generated by energy demand of wwt –Highly depends on technology 1/3 of N and P to water, 2/3 to atmosphere and soil Zseni, A. - Nagy, J.

Széchenyi István Egyetem Human excreta as a possibility for sustainable development in faeces and urine together Our calculation based on Tanguay [21] (kg/person/year) based on Jönsson et al. [26] (Sweden) (kg/person/year) based on Vinnerås et al. [27] (Sweden) (kg/person/year) based on Schouw et al. [25] (Thailand) (kg/person/year) N P K ingredient In excreta: Hungary/year (10 million people) (thousand tons/year) Nutrient loss due to soil loss in Hungary (thousand tons/year) Active ingredient content of fertilizers used in Hungary (2012) (thousand tons) N P K ,5 Zseni, A. - Nagy, J.

Széchenyi István Egyetem Nitrate pollution of soil, water and underground water decreases Direct composting of human excreta Use of fertilizer and slurry decreases significantly  their unfavourable environmental effects also decrease Inorganic N and P load of surface water caused by human excreta stops The nutrient content of human excreta goes back to the natural biological cycles Water consumption decreases The household waste water does not contain human excreta, so more simple or even on-site wastewater treatment of greywater could be used Eutrophication may reduce significantly human excreta must be composted with added vegetable cellulose  suitable C/N for humus forming Use of energy and mineral resources decreases Energy and cost demand of sewage drainage and waste water treatments decrease significantly (  reducing of uses of energy resources, reduce of CO 2 emission) It does not intervene in the natural water cycle Exploitation of soils and soil erosion is reducing The amount of waste water sludge decreases significantly Food production becomes more sustainable SZE: Zseni, A. – Nagy, J.

Széchenyi István Egyetem Conclusion More widespread agricultural utilization of human excreta is needed in any case in the future Human excreta is also a part of the biosphere, and its leading back into natural cycles is the essential basis for future food production  regarding the annually loss of soil mass and soil fertility on the Earth  the cost, material and energy demand of fertilizer production and utilization  freshwater pollution  the decreasing amount of good quality water resources  and the effects of global warming  We need to shift to using such methods which reducing water consumption and preventing water pollution  Food production must become more sustainable Zseni, A. - Nagy, J.

Széchenyi István Egyetem What does the Earth ask for? Not into water! Into the soil! As real humus forming organic matter! SZE: Zseni, A.- Nagy, J.

Széchenyi István Egyetem Thank you for your attention! Zseni, A. - Nagy, J.