₦airaland Forum

DAY EIGHT

Gas Formation

Gas formation will start after about two days of feeding the digester with cow dung slurry. You can see here in these photographs that the gas holder tank started raising along the guide pipes.

But, this gas contains lot of impurities and will not burn. Moreover, there was air present in the gas tank when we placed it over the digester.

Once the gas tank is full, this gas will be released to the atmosphere.

Type of Material which can be used for Feeding the Biogas Plant

Once the gas formation starts, you can feed waste material to the digester. The following are some of the wastes commonly available in a household

Rotten vegetables
Vegetable peels
Fruit skins
Left-over spoiled food which are unfit for consumption
Very sour curd unfit for consumption
Left-over vegetable oil used for frying
Grass and weed clippings
Dried flowers
Tender banana stems
Cattle waste like cow dung, goat dung and poultry waste
Leftovers coffee grounds and leftover tea leaves
Water used for rinsing rice and pulses. You can use this water for diluting the feed material

This list is endless... there are so many organic waste material you can use in the anaerobic digester. Make sure you chop them into pieces as small as possible. However, avoid certain items given in the next lesson which are unfit for feeding the biogas plant.

***Remember, food is precious. Do not waste food. Use only spoiled food which is unfit for consumption

More pictures

Even more

The last set of picture

Materials unfit for Biogas Digester

Avoid the following type of materials in a Biogas plant

Dry skins of Onion and Garlic
Egg shells
Fibrous materials like coconut husk
Bones, raw or cooked

PICTURES

Do have yourselves a wonderful night rest.

Dexpro:
Do have yourselves a wonderful night rest.

nice one man..lesson continues tomorrow right?

@DEXPRO,
Well done sir, more grease to your elbow

Yes Sir

BluePearls:
nice one man..lesson continues tomorrow right?

You have been the only person that have actively contributed to this thread, Well Done.

confluence:
@DEXPRO,
Well done sir, more grease to your elbow

At this stage, i expect constructive questions but it seems non is coming.

How would you remove the Impurities present in the Gas?
I am also quoting you from the above "Moreover, there was air present in the gas tank when we placed it over the digester.
Once the gas tank is full, this gas will be released to the atmosphere’’
How would you remove the Impurities present in the Gas?
According to your above quotations: How would you utilize the Gas once it is released to the Atmosphere? Please respond as fast as you can.


Gas formation will start after about two days of feeding the digester with cow dung slurry. You can see here in these photographs that the gas holder tank started raising along the guide pipes.

But, this gas contains lot of impurities and will not burn. Moreover, there was air present in the gas tank when we placed it over the digester.

Once the gas tank is full, this gas will be released to the atmosphere.[/quote]

How would you remove the Impurities present in the Gas?
I am also quoting you from the above "Moreover, there was air present in the gas tank when we placed it over the digester.
Once the gas tank is full, this gas will be released to the atmosphere’’
How would you remove the Impurities present in the Gas?
According to your above quotations: How would you utilize the Gas once it is released to the Atmosphere? Please respond as fast as you can.

Fantastic, this is really awesome. Op I salute you.

Boss.... am just seeing another means of making more cash next year (Ale-Air Biogas) ... I have stream more than 5 video on these since last week and I learnt that one can transfer the gas been produce into cylinder if am right.
Please what will be estimated cost of setting up a plant that can produce 25/50 kilo of biogas daily sir....
Your advice is welcome sir...

I salute you Engineer. Came across this thread today. Funny enough my cousin asked me a few days ago if I had any idea about biogas production. I'm going to recommend this to him. Thanks for the effort you took to write all these.

You are a very good teacher sir, so don't be surprised if you don't get too many questions from us because everything is so clearly explained you left little room for questions.

I know most questions will be mostly related to how much it would cost to do this.

How can we avoid Danger/Fire Outbreaks in this whole thing.


What Measures should be put in place to avoid Risk/inhaling unwanted/harmful gases.

Regards!

akinz4:
How would you remove the Impurities present in the Gas?
I am also quoting you from the above "Moreover, there was air present in the gas tank when we placed it over the digester.
Once the gas tank is full, this gas will be released to the atmosphere’’
How would you remove the Impurities present in the Gas?
According to your above quotations: How would you utilize the Gas once it is released to the Atmosphere? Please respond as fast as you can.


Gas formation will start after about two days of feeding the digester with cow dung slurry. You can see here in these photographs that the gas holder tank started raising along the guide pipes.

But, this gas contains lot of impurities and will not burn. Moreover, there was air present in the gas tank when we placed it over the digester.

Once the gas tank is full, this gas will be released to the atmosphere.

The first gas generated by your plant will contain a lot of impurities. When i say release the gas to the atmosphere, it means the impurities in the gas will not make it burn, so what will you do with it? Nothing. Then the best option is to release the ¨USELESS¨ gas out of the gas tank. Hope you understand?


Biogas can be purified using a special device. We'll get to that aspect soon.

Good work sir @Dexpro I guess questions were not coming because there wasnt any unclear detail about the whole process.
.
But one question i would like to ask is this; since the Gas Holder was turned on the Digester, isnt there any escaped gaps on the side (Where arrows point at) where the gases can leak out from? Or did you seal it round?
.
I hope the attached picture clearly explains what i am saying.

@DEXPRO, Master i came late to class today, my question is how long does it takes for the waste food and those rotten to start decompost and form the bio gas , i read somewhere online saying 2-3 weeks ,is it that long?

BEAUTIFUL QUESTION. The sides you pointed to were not sealed. Now this is the logic: The GAS HOLDER TANK is actually sitting on the content inside the digester, the weight of the gas holder tank will make it sink like some inches into the mixed dung. N.B The upper part of the gas holder tank will contain air thereby making it float. The outer ring outside the gas holder tank is not relevant.

ewizard1:
Good work sir @Dexpro I guess questions were not coming because there wasnt any unclear detail about the whole process.
.
But one question i would like to ask is this; since the Gas Holder was turned on the Digester, isnt there any escaped gaps on the side (Where arrows point at) where the gases can leak out from? Or did you seal it round?
.
I hope the attached picture clearly explains what i am saying.

pls I need a practical class of this lecture and pls like how much will it cost if am to construct for 2 bedroom house

Op, I happened to stumble on ur thread today and I will say you the master,no flaterry. My question is that will salt in spoilt food not affect the production of gas? I was told that omi ogi(the water gotten from pap preparation) can be used as a catalyst, how truei is that?

@DEXPRO,
Class to commence soon ,in this era of subsidy removal and serious economic crunch, i need all the details to construct my own Bio gas plant

Afoskalex:
Op, I happened to stumble on ur thread today and I will say you the master,no flaterry. My question is that will salt in spoilt food not affect the production of gas? I was told that omi ogi(the water gotten from pap preparation) can be used as a catalyst, how truei is that?

Fenkx for the compliments. Too much salt may affect but not the small quantity added to the food we eat.

Yes the water gotten from pap can be used as a catalyst

Sure you will

confluence:
@DEXPRO,
Class to commence soon ,in this era of subsidy removal and serious economic crunch, i need all the details to construct my own Bio gas plant

DAY NINE

How Much to Feed...?

Once gas formation starts, you can start feeding the digester regularly with wastes from kitchen and home garden. But the big question is How much waste we can feed ?

Here, the capacity of my digester is 750 liters. So I will feed about 3500 to 4000 grams of waste in this plant daily.

Why this much quantity only ?

All solid wastes we feed into the digester will take between 30 to 50 days to get fully digested based on the type of waste. For example, cow dung will take about 30 days for full digestion and solid vegetable wastes may take 50 days. This is known as Retention Time.

By adding the wastes in small quantities everyday, I will have a regular supply of about 750 grams of gas after about 30 days. This will assist the wastes to get fully digested and release optimum gas and get discharged through the slurry outlet pipe. Overfeeding the digester will drain out the partially digested wastes, which will increase acidity of the slurry in the digester as well decrease the colony of microorganisms working on the wastes.

As a thumb rule, for 1000 liter capacity digester, feed approximately about 5000 grams of waste.

Also, the solid wastes should be made into chunks as small as possible. Here, you can see in the photographs above that I have used an old mixer grinder to pulverize the larger chunks of vegetable waste.

A Vented Ram for Pushing down Larger Chunks and Agitating the Slurry

After feeding kitchen waste through the feed pipe, you may find some larger chunks floating inside the feed pipe. I have made a small vented ram using some scrap material and a one meter long 32 mm pipe. This ram can be used inside the feeding pipe to push down the chunks down. The vents in the ram will allow the water to seep through, thus making it easier to operate inside the feed pipe.

Repeated up and down movements of the ram inside the feed pipe not only help in pushing down the larger chunks, it will also help in agitating the slurry inside the digester and help in releasing trapped gas. This will also break down the scum formed on the surface of the slurry and accelerate the digestion process.

Wash the ram with clean water after every use.

More

[size=15pt]A Word of Caution: NEVER TRY THIS!!![/size]

Real Story... One student who got guidance from me over telephone, constructed a mini biogas plant for school exhibition and was over enthusiastic... She opened the gas valve from the gas holder and tested whether the gas burns or not by holding a burning match stick in front of the gas pipe. The entire gas tank exploded. Fortunately, nobody was injured but they had to spend lot of time to clean up the mess.

Never do this... only use a Biogas stove or a Bunsen burner or a suitable nozzle arrangement to test the gas.