AS BIOGAS PLANT

Question 1

plant used to process animal wastes or manure to produce biogas and sludge consisting of an
inlet/mixing tank, digester, gas chamber and outlet/sludge tank

Answer 1

biogas plant

Question 2

biogas plant where the digester and gas chamber form one unit

Answer 2

integrated plant

Question 3

digester and gas chamber form separate units

Answer 3

split-type plant

Question 4

plant with series of digesters

Answer 4

multi-digester plant

Question 5

plant consisting of digester and a moving, floating gasholder that either float directly in the
fermenting slurry or in a separate water jacket

Answer 5

floating type

Question 6

closed digester with an immovable, rigid gas chamber and a displacement pit

Answer 6

fixed type

Question 7

plant consisting of a heat-sealed plastic or rubber bag (balloon), combining digester and
gasholder

Answer 7

balloon type

Question 8

chamber where manure and water are collected, stored and separated from heavy and nonbiodegradable materials before feeding them into the digester

Answer 8

collecting tank or holding tank

Question 9

serves as conveyor of the manure-water mixture or slurry from the mixing tank to the digester

Answer 9

inlet pipe

Question 10

any water and air tight container designed for the process of anaerobic microbiological
degradation of organic matter into which the slurry is introduced for digestion and
methanization

Answer 10

digester/biodigester/bio-reactor/anaerobic reactor

Question 11

division in the digester that prevent the slurry from premature exit into the sludge/outlet tank

Answer 11

baffle board

Question 12

mechanical device inside the digester used to stir the slurry

Answer 12

stirrer/mixer/agitator

Question 13

space inside or outside the digester for the collection and storage of biogas

Answer 13

gas chamber

Question 14

cantilever beam that holds the gasholder/movable cover in position at the desired biogas
pressure

Answer 14

gasholder retainer

Question 15

serves as conveyor where the effluent or the slurry is forced out

Answer 15

outlet pipe

Question 16

layer of compacted soil and gravel to support the digester wall

Answer 16

backfill

Question 17

amount of slurry fed per unit volume of digester capacity per day

Answer 17

loading rate

Question 18

organic material used to produce biogas

Answer 18

substrate

Question 19

adding or introducing anaerobic bacteria to the digester

Answer 19

seeding

Question 20

mixture of manure and water

Answer 20

slurry

Question 21

difference in height between the digester wall and the filling line

Answer 21

freeboard

Question 22

level of slurry when the digesters is at full load

Answer 22

filling line

Question 23

average period that a given quantity of slurry is retained in the digester for digestion

Answer 23

retention time

Question 24

materials that inhibit the normal growth of pathogens in the digester such as mineral ions,
heavy metals and detergents

Answer 24

toxic materials

Question 25

various processes that take place among the methanogens, non-methanogens and substrates fed into the digester as inputs

Answer 25

methanization or digestion

Question 26

anaerobic bacteria that act upon organic materials and in the process, produce biogas

Answer 26

methanogens

Question 27

temperature range of 20 o C – 40 o C where mesophilic bacteria operates

Answer 27

mesophilic temperature rage

Question 28

amount of biogas produced per day per cubic meter of slurry

Answer 28

gas production rate

Question 29

mixture of gas (composed of 50 to 70 percent methane and 30 to 40 percent carbon dioxide) produced by methanogenic bacteria

Answer 29

biogas

Question 30

layer of floating material (mainly fibrous) on the slurry

Answer 30

scum

Question 31

settled portion or precipitate of the slurry; a mud-like, semi-solid mass

Answer 31

sludge

Question 32

residue that comes out at the outlet after the substrate is digested/processed inside the digester

Answer 32

effluent