Objective
To establish a conveyor network and plant to recover biogas from effluent from 62 farms. Treated effluent is recirculated for irrigation and fertilization.
The plant began to treat zootechnic wastes in December 1988. From that date, addition of liquid manure and biogas production were stabilized and so the data produced for 1989 could be considered as a fair indication of productivity.
The average production of biogas in 1989 was 11.536 cubic meters per day of which 4.147 cubic meters/day was used for maize drying, hothouse heating, tobacco drying and mud dehydration, all in various proportions, depending on the season and availability.
According to the data accumulated, the plant has been able to attain the following data :
Liquid manure
input (mc/die) 753
Biogas production
(mc/year) 4.210.815
Electric energy
production
(kWh/year) 3.313.600
Thermal energy
production
M1Kcal/year from
cogeneration 5.964
Net energy producted
Electrical kWh/y 2.499.061
Thermical M1Kcal/y 18.105
To the following results must be added the use of secondary products from the treatment:
- Mud/sludge Packed (kg. 50) and used as organic fertilizer. A
commercial outlet is being sought.
- Purified water After an accumulation of gg 200 in containers, they are
distributed, through underground pipes and used to
irrigate an area of circa 1.200 hectares. The carrying
out of the project has not presented any particular
problems, on the contrary the technology used and the
process used has demonstrated ample reliability.
The energy produced by the plant is equal to a TOE/year 2.358.
The investment in reference to the production of a TOE of energy produced during the economic life of the plant is equal to : Lit/TOE 168.375
The cost per unit of energy produced is equal to Lit/TOE. 188.232
The total cost per unit produced is equal to : Lit/TOE 369.572.
The completion of the project has shown great reliability. Both the technology used and the process adopted show a notable possibility of use the method in other plants.
This project is conducted in 36 sq. kilometers of small and medium-sized cattle, pig and poultry farms with a combined herd equivalent of 62,000 pigs (48,000 pigs, 1,300 cattle and 95,000 poultry)
The treatment plant consists of one primary and one secondary digester, gas compressors operating at 220 atmospheres, motors, dryers (for tobacco, cereals, fodder and organic fertilizers), glasshouses and data gathering system. The conveyor network collects 883 cu. meters of effluent/day with COD. of 37,200 kg.
The two stage digester daily converts 35,000 kg. of volatile matter into 16,500 cu. meters of biogas of at least 70 % methane and 5,600 Kcal/m3 calorific value. This is used for combined heat and power generation for the drying of fodder and tobacco. Excess biogas is purified into methane and compressed to 220 atmospheres.
Topic(s)
Call for proposal
Data not availableFunding Scheme
DEM - Demonstration contractsCoordinator
06055 Marsciano
Italy