RIBE CENTRAL BIOGAS PLANT

Objectif

The objectives of the project are to demonstrate the socio-economic viability of centralized biogas plants for manure as part of a national programme to allow intensive stock farming under environmentally acceptable conditions. The demonstration plant will be situated at Ribe in Southern Jutland.
I. Krueger AS has developed the process design and supplied the plant on a turn-key basis through its 100% owned subsidiary Krueger-Bigadan AS. The plant is owned by Ribe Biogas A/S, a limited company with shareholders consisting of a farmers association, a power production company, a slaugtherhouse and various institutional investors.
Construction commenced in August 1989 and the first biomass was delivered to the Plant in June 1990.
The commissioning of the plant was done using a procedure developed at pilot scale. After 6 months of operation full hdyraulic loading was achieved at a retention time of 12 days.
Major technical problems encountered have included the precipitation of struvite in heat exchangers and pipes and a high level of hydrogen-sulphide (H2S) in the biogas.
Struvite is removed by periodically washing with hydrochloric acid and H2S is removed by adding ironchloride to the digesters.
Using actual construction costs and the 1991 budget for Ribe Biogas A/S, the payback period of the project is calculated to be 12.9 years. If the increased fertiliser value of the digested biomass is included the payback period is about 9.2 years. For future biogas plants the payback period is estimated to be 10 years, not including fertiliser value. The project can therefore be considered as a model for the environmentally safe handling of surplus organic waste in other regions of Denmark as well as in the entire European Community and Eastern Europe.
The project comprises the following parts and components:
- transport equipment for the transportation of manure from and degasified fertilizer to the individual farms.
- biogas plant
- gas pipe connection to the power plant
- power plant.
The biogas plant designed to receive 400 tons biomass daily, includes a 1 800 m3 primary manure storage tank, a macerator, a heat exchanger to heat the manure to 52-55 C, for pasteurization purposes, three batch methane bioreactors of 1 500 m3 each operating in parallel in the thermophilic range of temperature, three 2 000 m3 storage tanks for the digested manure, and a gas cleaning and compression unit.
The animal manure (162 000 m3 daily) will be transported from, and the degasified, digested manure (fertilizer) to individual farms by the Biogas Procurement Company.
The manure is received at the plant where the liquid part is fed to primary tank and the solid part dumped into the manured pit.
From the pit, the solid part is taken to the primary tank and mixed with the liquid part by means of a mixing arrangement.
The mixed manure is pumped through a macerator to the heat exchangers. The incoming manure is heated partly by means of heat exchange system extracting heat from the digested manure and partly by hot water heated in a gas boiler. The heated manure is directed to one of the three digesters. One digester is filled while digested manure is simultaneously emptied from one of the other digesters. The treatment process is a batch type operation. Manure will be retained for a period of approx. 10 hours at the process temperature of 52-55 C. When digested, the manure is pumped to the storage tanks. Three of these are situated on the site the rest at the user's premises. Downstream, 10 000 m3 biogas (55 % CH4) produced daily, will be used partly to fire a boiler to produce process heat for internal use, and partly conducted to a combined heat and power plant including gasotto engines totalizing 2.3 MW for a nearby district heating plant, thereby producing yearly 3 890 MWh electricity and 26460 GJ heat.
Monitoring includes biogas potential, manure volume and several operation and state parameters. Taking into account the energy production under Danish conditions, the increase in fertilizing value of the digested manure due to organic nitrogen mineralization and the environmental fringe benefit, namely the reduction of nitrate leaching from previous local dispersed manure storage places, an estimated simple payback period of 10 years can be calculated.

Programme(s)

ENG-ENDEMO C - Programme (EEC) of demonstration projects and industrial pilot projects (EEC) in the energy field, 1985-1989

Thème(s)

1.5 - PRODUCTION AND USE OF BIOGAS

Appel à propositions

Data not available

Régime de financement

DEM - Demonstration contracts

Coordinateur

KRUEGER AS

Contribution de l’UE

Aucune donnée

Adresse

ABOULEVARDEN 52
8700 Horsens
Danemark

Coût total