To my
understanding 1000 liter/40 = 25 liter. So it is advisable to feed 25
liter of food waste mixed with water. It means, your food waste is
already included in that 25 liter. I have read from this elsewhere, the
maximum ratio of food waste to water
you can apply is 1:1 (though to me its too much for the microbes to
handle). Roughly the maximum weight of food waste you can put is 12.5 kg
in which you add another half of water to add up to 25 liter as total
mixed. However its up to you what level of total solids you want to
practice by reducing the food waste within that 25 liter. The more
effluent you take out from the digester, the more bacteria you will
discard and that may affect whole digestion process and becoming slower
in producing gas.
To construct a simple biogas digester in the photo above is easy. The materials you need are readily available at any hardware store near your residential area.
Basically the system consist of:
1. Inoculum
2. Biogas biodigester
3. Biogas storage
4. Connection between biodigester and its biogas storage
Inoculum Inoculum is a starter for the anerobic fermentation process to begin. It consist of consortium of microbes to help in digesting suitable raw material and able to turn them into biogas and effluent that is more environment friendly within a short period of time compared to conventional aerobic composting.
Biodigester
What is a biodigester? The function is to contain the fermentation process of food waste occurred in an aerobic condition without any oxygen.
Biogas storage
Used tyre tube to contain and store biogas produced from the fermentation.
Connector
A silicon clear host to connect gas produced from biodigester to the storage bag.
Other accessories and materials needed
PVC pipe, silicon gel, plastic and metal valve, etc.
Want to construct your own low cost biogas biodigester ? CLICK HERE!
The most cheapest and easiest way to produce an inoculum is using digestate from working biogas digester. They are consist of active culture with stable activity because consist of varieties of microbes working together or consortium.
Next source is by taking a scoop of slurry or sediment from anaerobic pond. These are also active microbes we can used directly to produce biogas.
If you happen to live nearby cattle farm, dung is another source of microbes that can produce biogas.But to start with cow dung we need to mix it with water and ferment until it mature in which produces biogas.
Do not mistaken biogas with carbon dioxide. Biogas is flammable while CO2 is not.
So to produce biogas you can start with things that already around you.
I am very lucky able to find old air temperature data at my place. The average is like 26.8 celcius. So, according to David David William House
's graph, the approximate HRT is 45 days. So, it is safer for me to
decide to choose 50 days HRT for my digester. To determine how much to
feed daily is by calculating = digester volume (liter) / HRT (day) = 200
liter/50 days = 4 liter/day. Again, rule of thumb do not get solid food
waste over 50% of daily feeding volume. In my case for 4 liter feeding,
2 kg of food waste is the maximum volume then mix with 2 liter of water
to a total of 4 liter. If you do not have confident and do not want to
get your system sour lets try less than 50% food waste of your daily
feeding volume. Please try and error, experiment with your system and
you will learn a lot finding the most optimum condition to run your
system.
Want to construct your own biogas biodigester? Click here!
I have always think of ways to recycle my kitchen wastes. Living in
housing area with limited backyard space unable me to dig appropriate
hole to bury all my kitchen waste without leaving smelly odor. I don't
have any experience composting and food waste easily become smelly if
you do not handle them properly. Then I came across anaerobic composting
which is enclosed and used cow dung as starter. I feel this technique
is practical and easy to construct. To make it interesting, I want to
use a modified garbage bin and call it food waste recycle garbage bin just like
when you throw your usual wastes into a dustbin but mine is a little bit
different in which it can recycle organic wastes. That's how I came up
with the idea.
Its not really difficult. Take a normal standard garbage bin at modified it a bit by installing inlet for feeding, outlet port for effluent and outlet valve for biogas to be collected into a tyre tube. Its that simple.
Then I built bigger module have an upgrade experience from my first biodigester as above. The new digester is 160 liter and connected to 500 liter biogas bag as storage. I also found how to modify a normal burner into a biogas burner.
Now I convinced that biogas generated at home really can be used for cooking.
The first edition of the book quickly established itself as the book on
biogas generation. Now in a newly revised edition, David House brings
together all the information, from the most theoretical scientific
research to grass roots homescale trial and error.Here are the
detailed designs for generators and the knowledge, encouragement,
imagination, and humor you will need to build a generator of your own.
While biogas may not yet be a household word, you should consider it
seriously if you believe in the future of alternative energy.
Use biogas for illumination, cooking, water heating, refrigeration, space heating, and to fuel vehicles.
*Over
100 figures and tables
*All the necessary formulas
*6 model generators
and a design flow chart
*Complete list of resources
*Extensive
bibliography
What is inside? Table of contents of Complete Biogas Handbook is as below:
I: Overviews
1: This Book
2
2: Energy
5
3: Math
10
4: Biology
14
II: Parameters
23
5: The Airless World
24
6: TS, VS, FS
25
7: pH
26
8: Temperature
31
9: C/N
35
10: Percentage of H2O
46
11: HRT and Loading Rate
50
12: Agitation
52
13: Toxins
53
14: Pressure and Surface Area
56
III: Substrates
58
15: Purified Substances
59
16: Manure Substrates
65
17: Plant Substrates
73
18: On Growing
Substrates
80
IV: Uses
85
19: Scrubbing
86
20: Combustion
94
21: Illumination
97
22: Burner Design
101
23: Cooking
103
24: Water Heating
104
25: Steam
110
26: Refrigeration
112
27: Engines
113
28: Space Heating
121
29: Gas Requirements
125
V: Troubleshooting
128
30: Cultures
129
31: Startup
131
32: Scum
133
33: Foaming
137
34: Sediment
138
VI: Design
139
35: Basic
Generator Types
140
36: Heating Generators
143
37: Agitation
153
38: Gas Handling
157
39: Slurry and Effluent Handling
161
40: Pumping
163
41: Construction Materials
167
42: Sizing Generators
169
43: Safety
173
44: Economics
176
45: Design Process
181
VII: Plans
186
46: Pipes and Drums
187
47: Test Generator
197
48: Modular Batch Generator
200
49: Hybrid Generator
203
50: Home Wastes Generator
208
51: Continuous-Fed Fibrous Substrates Generator
211
VIII: Appendices
213
Appendix 1: Analysis
213
Appendix 2: Biohydrogen
217
Appendix 3: Agricultural
Use of Effluent
219
Appendix 4: Math of Gas Production
223
Appendix 5: Specific Gravity
227
Appendix 6: Drill Statistics
228
Appendix 7: Burner Design
231
Appendix 8: Vital Statistics of Gases
233
Appendix 9: K and C Values
235
Appendix 10: Steam Temperature, Pressure, Water Depth
237
Appendix 11: Heat Transfer in Pipes
238
Appendix 12: Decimals and Fractions
241
Appendix 13: Geometry, Trig
243
Appendix 14: Metric Conversion
245
Appendix 15: A Simple Method for Temperature Conversion
248
Appendix 16: Terms
249
Appendix 17: The Answers
253
Appendix 18: Bibliography
259
Appendix 19: Author’s Afterword
270
Appendix 20: Contents, Figures, and Tables
272
Appendix 21: Index and Authors
283
To get more info in depth about homemade biogas digester please read the manual below where you can get from Amazon.com.
