1 - Kerbside waste is collected by the Council or Waste Management company, dustbin and roll on roll off lorries bring waste to the composting site.
2 - Unloading waste on floor of reception building.
3 - Shredding in action. A mechanical shovel loads the shedder. A slow speed shredder fitted with a 150mm to 200mm screen is used for the shredding the green waste and food waste, this allows good blended of material and aids the composting process. Water, in the form of leachate, is added here to moisten the material to be treated which is essential for effective composting. After the waste is shredded and blended the material is transported to one of the in-vessel buildings in Barrier 1. Each vessel holds approximately 175 tonnes depending on the bulk density of the material.
4 - Loading inside building with Retractaroof fully open. The retractable roof allows loading with no height restrictions for the loader. After loading the building the roof is electrically closed.
5 - Re-circulatory Air System and Pathogen Kill. It is important for air to be introduced into the material to encourage aerobic activity. The air is forced through the mass by patented ground-level; air ducts. The roof once closed, creates a small void above the material creating good air circulation, temperature profiles, odour barrier and prevents scavenger activity (see diagram).
Another factor that is essential for composting is heat. Six temperature probes are inserted throughout the material in the clamp. The temperature data and time are recorded then stored on a PC. Here temperature profiles are created. To ensure that all bacteria activity ceases the material must maintain a minimum temperature of 60˚C for 2 days. The temperature profile is a visable record that this has occurred. The material stays in this building (Barrier 1) for one week. To ensure that no cold spots occur the partly composted material is transferred to another in-vessel building (Barrier 2) for a further week, again, 60˚C must be reached and maintained for a minimum of 2 days.
6 - 7 Unloading & Maturation. After this final week the building is unloaded and the compost is transported to an outside concrete pad where the material, devoid of all pathogens, is matured for a further 6 to 8 weeks. During the maturation period the compost is moved approximately once a week.
8 - Screening the matured material. The composted material is screened to remove any unsuitable material that may have escaped earlier separation. There are a number of options for screening depending on the end outlet for the compost and the division rate that you are trying to achieve. Firstly the material can be screened at 10 to 15mm to create a fine compost, then if required the material can be screened again at 45 to 50mm to create a mulch like material.
9 – 10 Finished Compost. Finished compost can be transported in bags or in bulk. The composted material is a sanitised product which can be used in horticulture or agriculture as a growing medium and soil improver.