Home 5 Our Process

Our Process

In 2018, Brewster Bros invested in a state-of-the-art wash plant to recycle construction, demolition and excavation waste. Our wash plant is the core of our business. It’s the largest recycling plant of its type in the UK and is helping shift the way the construction and demolition industry in Scotland treats waste and consumes natural resources.

Brewster Bros closed loop

Circular Economy

The wash plant is a closed loop system, recycling up to 90% of the water it uses and producing minimal residual waste. Any organic matter is composted here on site and used to restore the wider site to further minimise waste.  It takes a whole year to fill just one of our trucks with the residual waste (such as plastic foils and polystyrene) that is removed by the plant. To put that into perspective, over 305,000 tonnes of waste come through the plant in a year and less than 30 tonnes of that can’t be recycled and is recovered for energy as a Refuse Derived Fuel. That’s 0.01% residual waste and zero waste to landfill.

Putting waste to landfill is harmful to the environment and with construction and demolition waste accounting for over 50% of Scotland’s total waste, it’s easy to see that this method of waste management isn’t sustainable.

By recycling your waste you’re:

  • Saving £3 per tonne by avoiding paying landfill tax.
  • Helping the environment by reducing carbon emissions.
  • Minimising the damage caused by landfill

By using recycled aggregates: 

  • You’ll save £2 per tonne as you won’t be liable to pay the aggregate tax.
  • Helping the environment by reducing carbon emissions.
  • You’ll negate the impact of procuring virgin materials.
Construction's Impact

The Recycling Process Explained

  1. Step One:
    When we receive an enquiry for waste management or to purchase our recycled materials, we gather all of the relevant information from the customer to generate a quote. Once the price and volume is agreed, then we can schedule a time for our drivers to collect the waste or deliver the product to you.
  2. Step Two:
    This job management process from sales enquiry, to scheduling and fulfillment to invoicing is all taken care of by our digital jobbing system. The system allows us to operate completely paperless which makes your paperwork logistics a lot easier.
  3. Step Three:
    For waste management, we require a WM3 classification of material to come off site as non-hazardous before we can arrange a collection or drop off. On arrival, the waste is checked at the weighbridge to ensure it is consistent with the site investigation report and can be processed through the wash plant.
  4. Step Four:
    On entering the process, a powerful magnet removes any scrap metals before the waste is processed. The waste is then given an initial rinse and screened to remove anything over 40mm and separate it into either a coarse fraction (4-40mm gravel) or fine fraction (0-4mm sand).
  5. Step Five:
    Anything below 4mm (sand, silt or clay) is sent through the sand plant where centrifugal force is used to separate the denser sand from the less dense silt/clay. The sand then lands on a dewatering screen and is conveyed to either the sharp or soft sand stockpiles ready to be used. The remnants are processed through the water treatment system where flocculant is firstly added to help settle the silt and clay out of the water in the clarifying tank.
  6. Step Six:
    The clean water then filters through a final ‘piano wire’ screen where floating micro organics are removed before entering a holding tank to be recirculated around the plant.  Meanwhile, the silt/clay slurry is pumped from the bottom of the thickening/clarifying tank into buffer tanks before being pumped into the filter press. The press acts like a giant vice and squeezes the water from the slurry at high pressure leaving a high quality impermeable cake behind that is useful for water attenuation and general fill applications.
  7. Step Seven:
    By the end of the process, the plant will have cleaned, separated and sized the waste into high quality usable materials. The five core products that come from our wash plant are: 0-2mm soft sand, 0-4mm sharp sand, 4-10mm gravel, 10-20mm gravel and 20-40mm gravel.