New £24M STW built for Grangemouth region
A new STW is being built at Kinneil Kerse in Scotland, to treat sewage from the Grangemouth and Falkirk area. The plant should be completed by 2001.Civil works on the Kinneil Kerse STW in Scotland have been completed by Paterson Candy, in a joint venture with Henry Boot. The mechanical and electrical construction phase is now underway. East of Scotland Water (EoSW) has invested £24M in the scheme, which will serve 90,000 people in parts of Grangemouth, Falkirk and Polmont.
The new STW will provide an increased treatment capacity of 55Ml/d, with an anticipated dry weather flow of 23.5Ml/d. Formula A flow has been estimated at 99Ml/d. The Kinneil Kerse plant has been designed to ensure EoSW meets the requirements of the EC's urban wastewater treatment directive. Kinneil Kerse STW discharges into the River Avon, which then flows into the Forth Estuary.
The treatment works is fed by four pumping stations at Bowhouse, Zetland, Northfoot and Polmonthill. They will deliver flow via a 42in main to Kinneil Kerse.
Polmonthill is an existing works which will be modified to a pumping station using the existing primary tanks as storm tanks. Bowhouse and Northfoot are two existing pumping stations which will be refurbished. A new pumping station will also be built at Zetland Park.
The main treatment process will comprise inlet screens, degritting, storm tanks and sequencing batch reactors (SBR). As part of EoSW's waste disposal strategy, Kinneil Kerse has also been designated a regional sludge centre. Sludge from the works will be dewatered, and mixed with sludges from other STWs in the region.
The sludge will then be thermally dried to produce a granular product with a view to use as fertiliser. With an output of around six tonnes of granules per day, it will be one of the largest drying plants in Europe.
The works will be controlled by a networked PLC system complete with a PC based SCADA system. Each PLC will send control signals to the plant and receive status signals from the plant and will be responsible for controlling its own sphere of influence such as the sludge plant. The SCADA system will comprise two IBM compatible PCs - one for run time and one on standby. These units will be connected to the PLC network and will enable operator control, display of plant status and trend displays.