Wiefferink - Service Boxes for AD Plant Agitation

Wiefferink Service Hatch/ Agitator Installation

Particularly suited to Biomethane plants, that need to ensure an 02 free gas supply.

The agitator service port that allows agitator service / replacement whilst the roof remains inflated, and the digester remains in operation, producing gas, and preventing contamination with air.The system is based around a stainless steel platform that is bolted to the topmost rim of the digester vessel, immediately above the appropriate agitator-­ mounting pole.

The platform has a support underneath that not only supports the weight of the structure, but also acts as a gas barrier whilst service work is under way. 
Above is a similar stainless steel band that runs across the rear of the platform, and acts as the connection point for both air inflated and gas membranes. 
In this vertical plate can be mounted viewing windows, gas outlets, over pressure device outlets, + any other service connection point that may be required.

Upon the flat surface of the platform, is a raised plinth with a detachable lid, and it is through this lid that the agitator can be inspected or removed. 
The agitator raising/ lowering winch, and rotating device also penetrate the platform via gas proof methods. 
To remove or inspect   the agitator, it is necessary to raise the liquid level of the substrate by circa 150mm, so that the substrate acts as the gas-­‐proofing medium for the area within the service box, and the digester gas storage area. 
In so doing, the gas within the main gas store remains free of any air contamination, but also cannot escape into the service box zone, thus creating a proportionately safe working environment. 

However it should be noted that all works undertaken upon the service box should be carried out by fully qualified service engineers   using appropriate PPE and following correct procedures.