Bio Gas

              HOW BIOGAS WORKS . 

Organic wastes such as human feces, cow dung, vegetable scraps, and green waste or anything that can rot can be used to produce biogas. The waste is mixed with water and loaded into an anaerobic digester. The biogas is approximately 65% methane and 35% carbon dioxide and several other gases at low concentrations. The anaerobic digester collects the biogas as it bubbles to the surface.

 After the bacteria have consumed the energy from the waste there are still leftover solids which can be used as fertilizer.  Organic fertilizer from the leftover also contains more micronutrients than chemical fertilizer; hence replenish the soil for long lasting soil fertility.  It can be used to increase production of cattle feed, creating a virtuous cycle that improves biogas output and farm productivity.

         

                                                         HUMAN WASTE        BIOGAS SIZES 

CUBIC METRES

No. of persons

APPROXIMATE AMOUNT

6m3

1 – 5 0

181,000.00

8m3

50 - 70

196,050.00

10m3

70 - 80

222,350.00

12m3

80 - above

238,500.00

  BILL OF QUANTITIES FOR BIOGAS CONSTRUCTION  

Biogas digester size

6m3

8m3

10m3

12m3

Number of persons

1 - 50

50 - 70

70 - 80

80-  above

Estimated construction period (in days)

14

16

18

20

Construction materials

 

unit

App. price

quantity

quantity

quantity

quantity

River sand

tones

1200

5

6.5

8

10

Rough stone

tones

1250

6

7

9

10

Quarry stones can also be used

foot

65

230

250

300

350

Ballast size ¾” from hard stone only

tones

2000

3

4

6

7

Approximate total in Kenya shillings

19,500.00

24,550.00

32,850.00

38,500.00

Cement 50kg

bags

760

23

28

33

38

Water proof cement 1kg  (English)

kg

250

4

5

6

7

Twisted bar (Y8) or round bar(R8)

pcs

680

7

8

9

9

Round bar(R6) or (R5.5)

pcs

420

3

3

3

3

Pvc pipe 4 (heavy gauge) or bigger

pcs

1850

1

1

1

1

Binding wire

kg

180

3

3

3

3

Nails 3”

kg

150

1

2

2

2

Nails 4”

kg

150

1

1

1

1

plywood

sheet

700

1

1

1

1

Dome pipe

pcs

800

1

1

1

1

Manometer

pcs

1200

1

1

1

1

Washout pipe 1 ½” with plug

pcs

120

1

1

1

1

Polythene paper 1000 gauge

meters

200

3.5

4

4.5

5

Gl pipe (0.5 – 2”) min. 4mtrs or longer

pcs

2000

1

1

1

1

Dome bricks 230 x 110 x 70mm

pcs

0

250

320

360

380

Approximate total in Kenya shillings

33,000.00

38,000.00

43,000.00

47,000.00

Biogas piping, cooker and accessories

As per site

-

20,000

20,000

28,000

28,000

Casual  labor, miscellaneous

Approx.

-

33,500

35,000

38,500

40,000

Labor charge

approx

-

75,000.00

78,500.00

80,000.00

85,000.00

APROXIMATE TOTAL SUM FOR LABOR AND MATERIAL

KSH

-

181,000.00

196,050.00

222,350.00

238,500.00

NB: 6 MONTHS – 1 YEAR WARRANTY, AFTER SALES SERVICE AND USER TRAINING.

 

ADVANTAGES OF BIOGAS

  1. Improves health due to lack of indoor pollution.
  2. Free fertilizer.
  3. Saves money and time and it’s also durable since it has 30 years life span.
  4. Conserves the forest since no firewood cutting and felling of trees for charcoal burning

 

University of NairobiICT