Devonport EfW

The Problem

MVV are currently constructing an Energy from Waste (EfW) plant in Devonport, Plymouth. The Combined Heat and Power (CHP) facility will use energy stored in Non-recyclable waste to produce heat and electricity that will be supplied to Devonport Dockyard with surplus energy being supplies to the national grid. The plant will generate 800,000 tonnes of steam (at 60 bar / 420oC) and 190,000 MWh of electricity per year. Precision Grouting work was required to the steel support stanchions of the steal frame and to the bases of all the plant equipment with in the facility.

The Solution

The voids were cleared of any dust, debris or any other contaminants. After constructing temporary box shutter with 25mmx25mm Arris rail to give a chamfered edge finish, the Arris to grouted was pre soaked with water before one of the following procedures were carried out:

1. Gravity pour the mixed grout into one or more open sides of the shuttering created during the building of the temporary shuttering.
2. Gravity pour through a hopper (letterbox) into the shuttering again created during the building of the temporary shuttering.
3. Where gaps are small (up to 250mm x 250mm) use hand held injection gun filled with grout to pump grout into the void via a drilled hole in the shuttering.
4. For the larger baseplates a conventional diaphragm pump will be used to ensure adequate volumes are correctly injected.
After allowing curing, return and remove the temporary shuttering and make good any minor edge details. The products that were used for this were: Fosroc Conbextra GP and Fosroc Conbextra HF Page-Grouting V1/50