LYTAG lightweight aggregate (LWA) is specifically designed and manufactured to meet the requirements of modern construction practice. The raw material is pulverized fuel ash (pfa), the waste produced from electricity production in coal-fired power stations. The aggregate formed is 'sintered pulverized fuel ash lightweight aggregate', more commonly known as LYTAG lightweight aggregate.
LYTAG LWA is made by pelletizing the ash. By adding a controlled amount of water in specially designed pelletizing pans, rounded pellets are formed. The pellets are then heated on a sinter strand to a temperature of around 1100°C. The result is a hard, honeycombed structure of interconnecting voids within the aggregate. The pellets formed are rounded in shape and range in size from 14 mm down to fines, these are processed to the required grading, depending on the final use.
- LYTAG LWA:
- Is approximately half the weight of natural aggregate and can replace natural aggregates in many construction applications.
- Using LYTAG LWA in concrete, both precast and in situ, can reduce the dead weight by over 25%, allowing savings to be made in foundations and steel reinforcement, while still retaining the required structural performance.
- LYTAG LWA roof and floor screeds offer a wide range of benefits over traditional screeds, including weight savings of around 50%, improved thermal properties, reduced costs, reduced shrinkage and ease of placing.
- Due to its rounded nature LYTAG LWA is ideal for drainage applications, the excellent hydraulic conductivity makes for quick removal of water, however the high absorption allows retained moisture to return to the ground during dryer spells.
- It does not cause damage to the plastic pipes.
- It is also used for bulk fill, arrestor beds, refractory concrete and filter media.
- Lytag Ltd supply products for specialist markets, for example HORTAG LWA has significant value in horticultural applications, including use as a supporting medium in hydroculture and as an ameliorant to topsoil in lightweight beds for roof top landscaping.
- Being wholly manufactured from a waste stream, LYTAG LWA is a sustainable secondary aggregate that prevents material going to landfill and reduces the burden on natural aggregate resources.