The Process

The waste is first screened at 100mm to remove any oversize material that could damage the plant, it is then passed under a strong magnet which removes any metals that may be present in the waste, the waste then travels up a feed conveyor to the first stage of the washing process.

The material is fed into a washing and screening system where the waste is separated into oversize (40-100mm), shingles (4-40mm) and sands (4 & 2mm down). Oversize is stockpiled for further processing into sub base aggregates, shingles and sands are sent to separate processes to refine and clean the products.

Shingles (4-40mm) are fed into an item of plant called a logwasher, this consists of two shafts with blades attached to them, these blades agitate the aggregate against itself, whilst it is constantly being sprayed with water, this scrubbing action causes any fine material (eg clay & sand) to be separated from the aggregate and get carried away with the waste water. Lightweight contamination (eg paper, wood & plastic) are floated off in the logwasher, dewatered and stockpiled as waste.

The material exiting the logwasher is clean scrubbed 4-40mm aggregate, this is then passed onto a sizing screen to separate the three coarse single size shingles, 20-40mm, 10-20mm and 4-10mm.

Sands (4 & 2mm down) from the first washing & screening system enter a large tank, in this tank two bucket wheels remove the heavy sand particles from the silty washwater, the silty washwater from this tank is then sent to two hydrocyclones (one for each sand type) where very fine silt & clay particles (less than 1/15th of a millimeter) are removed from any residual sands using a principle similar to a dual cyclone vacuum cleaner, the resulting sands are dewatered and stockpiled as 0-2mm soft sand and 0-4mm sharp sand, the silts & clays are pumped with the wash water to the silt management system via a dewatering screen which removes any lightweight contamination.

The residual silty washwater is deposited in a settling tank where the silts settle out from the washwater, aided by a material called flocculant which draws the fine particles to the bottom of the settling tank, the settled silt & clay is then pumped to a lagoon where it continues to dry, the clean water from the top of the settling tank is then reused by the washing systems, this forms a closed loop water management system whereby all the water used in the system is constantly recycled.

Click here to see the flow chart
Click here to download flow chart and Hadley's brochure as a pdf.

All products comply with the the WRAP quality protocol.

Hadley's believe in sustainable solutions and is passionate about conserving the planets natural resources; we have a responsibility to the environments in which we operate. We want to deliver our passion to our customers using the latest technology and our integrated processes, this in conjunction with our highly motivated and technically competent employees is how we maximise wealth for our shareholders and create value for all of the stakeholders.