economic and ecological analysis of household biogas ... material/session_day 3/3...universität...

Universität Stuttgart

Economic and Ecological Analysis of Household Biogas Plants in China

Dipl.-Ing. Jingjing Huang, Dr. Klaus Fischer, Prof. Martin Kranert Institute for Sanitary Engineering, Water Quality and Solid Waste Management, University of Stuttgart Bantäle 2, 70569 Stuttgart, Germany


Background:

• Energy scarcity worldwide • High pollution from conventional energy • Serious hygienic problems and environmental damage by untreated organic wastes in many developing countries, especially in the rural area • China as the biggest biogas producer and consumer has rich experience in this technique.


China: biggest biogas consumer in the world

Start: at the End of 1960´s

by the end of 2009, ca 35 million household biogas plants

And more than 4 million new plants are increasing every year.

annual biogas production has reached 10.4 billion m³.


Houshold biogas digester in china

The volume of these household digesters is ca. 6-10 m³.

Life time: 15 years

Productivity: 0.15 - 0.25 m³ per m³ digester per day

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Use of biogas for household

Cooking,

lighting,

heating,

gas welding,

also as fuel for the internal combustion engine

…


Use of fermentation residue


"four-in-one„ biogas modell in north of China

More than 400,000 “four-in-one” biogas modell


„Pig-Biogas-Fruit“ modell in south of China

More than 2.5 million “pigs-biogas-fruit” biogas modell


Economic aspect

Invest costs South of China

(EURO) North of China

(EURO) High land of China

(EURO)

Biogas Digester 220 230 260

Three reforms 180 260 160

Fruits garden/ green house 150 800 120

Summe 550 1290 540

Financing from country 120 150 300

Operating costs and maintenance cost: • Staff cost for Fault diagnosis, regular check, training on biogas technology, • Costs for maintenance materials and change of spare parts Around 30 € per year


Economic Benefit

859 942

360

0

200

400

600

800

1000

Süden Chinas Norden Chinas Hochplateau Chinas

[EU

RO

/a]

Normally, after 1-2 years can cover the invest cost.

Generally, biogas technology has following economical benefits:

• As alternative energy: saving traditional fuel sources and electricity cost for light

• Reduction in need of chemical fertilizer and pesticide

• Livestock development

• Improve the soil productivity, and so increase the agricultural yield


Ecological Analysis

• Solution of the environmental problems caused by

human and animal feces • Protecting forest and Fossil energy substitution • Reduction of Greenhouse Gas • The soil can be improved • Avoiding the pollution from organic waste

• prevention of land-fertility degradation due to the

excessive use of chemical fertilizers


Substitution of fossil energy

Biogas Pit coal Firewood Straw liquidgas Electricity

Average heating value [kJ/m3] or [kJ/kg] or [kJ/(kW*h)]

20921 20908 16726 14636 50179 3600

Thermal conversion efficiency from cooker

60% 35% 25% 25% 60% 80%

annual average amount [m3/a] or [kg/a] or [(KW*h)/a]

341 584 1022 1168 142 1484

8m³ biogas digester will save 0.5 ton of coal or 1 ton of firewood per year.


Reduce of greenhouse gas

Emissions GHG, fuel = Fuel Consumption fuel Emission Factor GHG, fuel

8m³ Biogas Digester will reduce 0.8 ton greenhouse gas per year (CO2 equivalent) In China: 1990 ~ 2005, 15 years: total 88 million ton greenhouse gas have been reduced

CO2-Reduction by use of biogas Coal Wood Straw Biogas

annual average amount kg/a or m3/a 584 1022 1168 341

CO2 emission factor g/kg or g/m3 2026 1873 1464 1142

Annual CO2 emission volume kg/a 1184 1915 1710 389

Reduction of CO2 emission kg/a 795 1526 1321


Social benefit

Health improvement—disease caused by smog in traditional

burning style and polluted surface water and groundwater Improve the household sanitation Decrease the burning accidents Save the working time on firewood collection and cooking,

have more time for social activities and household works Job creation for local people Improve the quality education


Situation of disease

Disease Biogas-User Biogas-Non-User

Ascaris [%] (Ascaris lumbricoides) 3.9 11.2

Ancylostomiasis [%] 1.3 5.4

Schistosomiasis [%] 1.4 1.7

Enterobius [%] 0.2 1.7

Eye disease [%] 0.7 1.2

Intestinal disease [%] 1.2 3.7

Unknown [%] 1.7 2.7


Social Benefits

Saving of working hours compared with Biogas-Non-Users :


Improving sanitary status in rural areas

• Investigate 1619 biogas users about the Sanitary status of rooms, kitchens, drinking water sources, lavatories and yards

being good were more than 50%

• 48 samples to examine eggs of parasites such as ascarid,

hookworm, flagellate, pinworm and schistosome :

96% of them reached the GB7959-87 Sanitary Standard for the non-Hazardous treatment of manure

• The biogas construction and comprehensive utilization is an

effective approach to improve sanitary status in rural areas.

effects of killing parasite ́eggs, preventing infectious diseases and ensuring peasants ́health


Color Odor Turbidity PH-Value

Input material brown

stinks 4000 6.5

Output

material

Light brown

less stinks 640 7.4

Removal rate 84.2%

COD (mg/L) BOD (mg/L) Fäkal-

Coliforme [ml]

Amount of ascaris

eggs [pieces/100 ml]

Input material 5300 3200 < 0.004 20000

Output

material 780 400 0.6 2

Removal rate 85.3% 87.4% 95.59% 99%

Improve sanitary status in rural areas


Summary and Outlook

• Biogas technology: impact on aspects of energy, environment, agricultural production, socio-economic development, and health and sanitation.

• For solutions of the environmental problems and covering the

energy gap in developing countries.

• establish of organizations; started a series of the national and international biogas programs to facilitate the biogas development.

GTZ UTEC, SNV, Swiss contact, SEQUA and RELUX have initiated some cooperation with local

partners in Latin-American and Africa for the use and dissemination of biogas technology.


Thank you for your attention!

Jingjing Huang Institute für Siedlungswasserbau, Universität Stuttgart Bantäle 2 70569 Stuttgart Email: [email protected] Tel: 0049-711-68565477

mailto:[email protected]



economic and ecological analysis of household biogas ... material/session_day 3/3...universität...

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