Container concept

This year, SEVA Energie AG from Emstek in Lower Saxony has produced c. 200 block-type thermal power stations for biogas plants, of which around 70% have been delivered in containers. Unlike the reconstructed marine containers or converted pre-fabricated concrete transformers used on many biogas plants, SEVA uses a container specially manufactured for BTTP use.

ContainerbauweiseThese 3-chamber containers have, in addition to the generator room, a chamber for the control panels and a third chamber for the supply of used and fresh oil.
According to the type of block-type thermal power station to be installed, 30ft [c. 9m long] or 40ft [c. 12m long] containers are supplied. The 3m high and 3m wide 3-chamber container is larger than the standard containers otherwise supplied and meets the highest possible industry standards.

The greater volume of this type of container guarantees optimal ventilation and de-aeration of the generator room and makes operation and service work at the block-type thermal power station easier. Sufficient room volume permits the optimal positioning of the periphery of the block-type thermal power station and professional service and maintenance within an acceptable time-frame. Moreover, thanks to the container’s improved ventilation, localised overheating can be avoided, a particular advantage when the outside temperature is high.

The generator room’s optimised fresh-air supply alone is naturally not enough for the stable running of the plant. The intake air is therefore controlled by a control device which takes into account the requirements imposed by the outside temperature in summer and winter. SEVA makes this possible with temperature and pressure-controlled ventilators and self-closing shutters. The outside air sucked into the container is subsequently led into the generator by means of an intake pipe and mixed in order to obtain the optimal combustion temperature of 20°C. The intake air in a SEVA container is also sucked upwards to avoid, as far as possible, outside air contamination from dust etc.
Besides the regulation of intake air and combustion air, biogas processing is a further important factor in ensuring the stable and trouble-free operation of the block-type thermal power station. At SEVA, the processing of the biogas is ensured by passing it through a gas cooling system and an additional filter before it reaches the condenser.
The unusual width of SEVA containers also means that it is possible to install the heating distributors inside them and thus keep possible heat loss to the absolute minimum.

The second chamber is the control room and this is accessible from outside and from the generator room. This control room in itself is a considerable advantage thanks to the improved working conditions for maintenance and service work it provides. This separate room also facilitates the reading and evaluating operating parameters for the worker himself in the daily monitoring of the BTTP.

The third chamber of the SEVA 3-chamber container is also accessible from outside and contains the lubricating oil supply, with a 1 000l PE tank for used or fresh oil.
This oil supply room is fitted with a radiator so that the lubricating oil is protected from overly low temperatures in the winter months.

Only under these conditions, optimised for BTTPs, can the standard operating hours calculated for a block-type thermal power station of between 8 000 and 8 5000 a year be realised and the maintenance and repair intervals laid out in the maintenance plan be reached or improved upon.
This container manufacture method is becoming more and more popular with plant operators and also planners. The advantages described above which this high quality 3 chamber container, optimised for use in BTTPs, provides, guarantee stable and trouble-free block-type thermal power station operation and are thus also a guarantee of the economic success of the plant.