沼气技术

(3) “Five transformations” modes
Figure 3 Diagram scheme of “Four in one” modes
This mode is constructed by 5 parts which are biogas
digester , latrine , solar energy warm sphere , water storage pit and orchard irrigation facilities . Biogas digester is the core part of “ five transformation ” energy source ecology mode, we can integrate the rural production fertilizer consumption and the rural living energy consumption through the link function of high efficiency
biogas digester, forming “ herd—biogas—fruit ” interaccelerating positive ecology cycle system. Its structure is as shown in Figure 3.
(4) “Pig-biogas-fruit” modes
used as treating high concentration organic wastewater in livestock and poultry breeding farm, brewery and sugar refinery etc. Large and medium biogas plant includes: livestock and poultry breeding farm biogas
plant, treating industrial organic wastewater biogas
plant .
3.2.1 Processes of large and medium biogas plant
(1) Livestock and poultry breeding farm biogas
Biogas technology in china
Zhiying Yan Student number: 174 Chengdu institute of biology, CAS
1. The conception of biogas
what’s the biogas ? It is originally called swamp gas just because people found it in swamp area. Also, it is be called biogas due to production of this gas by biological metabolism under anaerobic conditions.
Chinese household biogas digester type are “ round, small or shallow ”, the general volume is 6 ~ 10 m3. the main structure are concrete, brick-and-concrete, brick-and-mud prefabrication and glass fiber reinforced plastic, moreover there are also semi-plastic and soft-bodied structure .
The digester is as shown in the following Figure 1. Before biogas generation, the liquid level of fermentation chamber is flush with those of inlet pipe and hydraulic chamber. With the gradual increase of biogas in fermentation chamber, the gas pressure increases and push fermentation chamber liquid to hydraulic pressure chamber till inner biogas pressure and outer hydraulic pressures are in balance. With the consumption of biogas, the biogas pressure decreases and the hydraulic chamber liquid flows back to the fermentation chamber to reach a new balance. Storage and discharge of gas are performed by continual changes in the liquid level of the pool.
2. The fermentation of biogas and its’ composing
Biogas fermentation, widely distributed in the nature, is the bioconversion process by which organic matter is degraded and converted into inflammable gas by many kinds of microbes at anaerobic conditions. Fermentation materials is very available such as human or livestock’ s manure, straw, waste water and waste residuals from factories.
“Pig-biogas-fruit” modes
“Five transformations” modes
(1) Typical hydraulic pressure digester in China
Figure 1 Diagram scheme of hydraulic pressure digester
3. Main biogas technologies in China
3.1 Household biogas technology
“One digester and three transformations” modes Household biogas technology “Four in one” modes
Its’ main composing is methane (CH4), which content is 55-70%. Then, it is carbon dioxide (CO2), which content is 30-45%. There is still a little nitrogen gas (N2), hydrogen gas ห้องสมุดไป่ตู้H2),sulfurated hydrogen (H2S), and so on. So biogas technology can not only treat organic wastes but also get a kind of clean and renew energy.
plant technology
The current treatment measures to wastewater
containing dung and stale in livestock and poultry
breeding farm is taken biogas plant technology as core, not only recycling energy source and qualified organic fertilizer, but also treating sewage and waste to standard discharges. Its process flowchart is as shown
(5) “One digester and three transformations” modes
To construct biogas digester, meanwhile reconstructing
stock and poultry feeding house, sanitary latrine and kitchen.
Kitchen transformation
Livestock house and latrine transform
3.2 Large and medium biogas plant technology
Large and medium biogas plant technology is main
(2) “Four in one” modes
Figure 2 Diagram scheme of “Four in one” modes
Constructing sunlight greenhouse in peasant household courtyard, constructing underground biogas digester in the greenhouse end, constructing pig house and latrine above the biogas digester, planting vegetables and fruit trees in the greenhouse. Its structure is as shown in Figure 2. In this mode, it takes the solar energy as the power and takes the biogas as the link, to combine planting and breeding, which not only forming ecology positive cycle, but also increasing income of Chinese peasantry.