What is Mechanical Biological Treatment?
Mechanical Biological Treatment (MBT) is a method of treating mixed household waste as well as commercial and industrial waste. The mechanical part involves removing materials that can be reused or recycled. This will consist of metals, glass, plastics, compost and stone or grit. These have value as a resource and are of limited or no use as fuel. In the biological process the waste will be shredded and craned on to a special bio-drying floor which lets air pass through it so any biodegradable materials rot faster. As the waste breaks down it generates heat which is used to dry and sanitise the waste, making it easier to process.
What is Anaerobic Digestion?
Anaerobic digestion, AD, is a series of processes in which micro-organisms break down biodegradable material – in a similar way to composting – in the absence of oxygen. It takes place in a warm sealed airless container. Anaerobic digestion is a renewable energy source as it produces biogas which can be used to generate heat and electricity and the material left over can be used as a soil nutrient.
Why can’t we just continue landfilling the waste?
1) Sustainability: This is not an environmentally friendly option for waste. It takes up valuable space and, once buried, it is not possible to recover any value from it by recycling or composting it. It also produces methane which is about 21 times more harmful as a greenhouse gas than carbon dioxide.
2) Recycling: Like other local authorities, Barnsley, Doncaster and Rotherham have been set recycling targets by the Government to reduce the amount of waste going to landfill.
3) Cost: The cost of using landfill sites will double over the next decade because of a shortage of suitable sites, an increase in tax to use them and environmental controls. Local authorities face increasing fines from the EU and UK governments if they do not cut the amount of waste being sent to landfill. These costs have to be passed on to local council tax payers.
Does it burn waste?
The MBT process does not involve burning waste at the Bolton Road site. At the end of the process a dried material is produced which will be taken to Ferrybridge and burned in a multi-fuel plant – producing sufficient energy to power 36,000 homes. The AD process also produces gas which will generate electricity.
How long is the waste in the building?
The drying process takes between 12-15 days. The waste reduces in volume by over one quarter and is then sorted and recyclable materials removed. The smallest waste, called ‘fines’, is then transferred to the AD building, where it is fermented for four weeks. This produces methane gas which will be used to generate electricity to supply the Bolton Road site with the surplus being sold to the National Grid.
Will the plants operate 24 hours a day?
Yes, but vehicles will arrive and leave between set hours, probably 06.00-19.00 on weekdays, or 06.00-16.00 at weekends.
Is it noisy?
No. The centre will be fully enclosed, so activities such as the unloading of waste will take place inside.
Will there be smells from the plant?
No. All operations take place inside the building. It will operate under negative pressure, which means that air will be sucked in rather than going out, and will be used in the drying and treatment process. All air released to the atmosphere will first pass through bio-filters, which stop smells leaving the plant.
What about dust?
All waste will be handled inside the facility. Any dust that is produced inside the facility will be drawn through the centre’s dust extraction system, so it will not be released outside.
Will there be smoke or gas coming out of the plant?
No. The centre will be stringently regulated by the Environment Agency, and the company will put in place a range of measures to ensure the facility does not have an impact on the local area.
Is there a risk to public health?
No. Emissions from the plants are strictly controlled (as explained above) and the whole scheme and its operations will have to be subject to a risk assessment.
What about lighting of the plant?
All lights will be shielded to ensure light is directed where it is needed and it does not create a glow in the night sky.
How big are the buildings?
The MBT building would be 16m high (at its highest point), 213m long and 76.3m wide. The AD building would be 15m high (at its highest point – except the chimney, see below), 88.8m long and 76.1m wide. The Next distribution centre, which is adjacent, is around 19 metres high.
Will there be a chimney and how tall will it be?
There will be a chimney stack above the AD plant for the venting of gasses. This will be 3 metres higher than the highest point of the roof (ie it will be 18 metres high in total). It is, by law, required to protrude 3 metres above the roof height.
Does the facility increase the risk of vermin in the area?
No. Shanks brings many years’ experience in building and managing such facilities
What about all the lorries?
Traffic movements will be a key part of the planning permission process. Routes and movements will be planned in order to minimise the impact on local communities and the environment, using major roads rather than urban and country roads wherever possible. Details of the proposed routes will be available at the public exhibition.
How many lorries a day will travel to the plant?
This will vary but the average total number of all vehicles, including lorries and cars, would be around 150 two-way movements a day.
What is a Waste Transfer Station?
3SE propose to operate Barnsley Council’s Grange Lane Transfer Station. Refuse collection vehicles from Barnsley deposit their loads here where it is held in bulk before it goes to the MBT plant in larger vehicles. This considerably reduces the number of journeys and impact on the environment.
Where is the waste coming from?
Nearly all the waste will come from Barnsley, Rotherham and Doncaster, the three councils in the partnership. The contract allows for some waste (on average 11,000 tonnes a year – less than 5%) to be brought in from outside the partnership area.
How many jobs will there be?
There will be around 40 new jobs generated at the Bolton Road plant and a further 25 at Ferrybridge.
How will you ensure that local people get a chance to apply for work at the new facility?
We are not allowed by law to reserve jobs for local people. However, we will ensure they are advertised locally and so many of the employees are likely to come from the local area.
What are the next steps?
A planning application for the 3SE proposal will be submitted in the Autumn of 2011.
If you get planning permission, when will the plant be operating?
Enabling works could start at the beginning of 2013. The new facility would then open in the Spring of 2015.
