Cement Kilns: Difference between revisions

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The introduction of waste materials - or 'Alternative Raw Materials' as coined by the industry - can be as part of the kiln phase or the final grinding stage and it can be used as an additive or as a fuel in the process.

'''In 1995''' there were 20 'cement factories' in the UK producing around 15 million tonnes a year of cement each year, with the cost of energy in the process representing 40 to 50% of running costs. There was a drive to substitute traditional fuels (coal and petroleum coke) with cheaper fuels slightly before this date, and trials were still running at this time with the ramifications of these trials captured in a Parliamentary Briefing Note<ref>[https://researchbriefings.files.parliament.uk/documents/POST-PN-60/POST-PN-60.pdf Parlimentary Briefing Note 60 April 1995]</ref>. [[Waste Derived Fuel]] had already started to play a more significant role in UK cement processing, in line with other countries (especially in Europe). It started with the use of solvent based hazardous wastes, often referred to as [[Cemfuel]] and by some as a [[Recycled Liquid Fuel]] ([[RLF]]), which was being trialed at a substitution of 50% of traditional coal fuel (although at the time 100% substitution occurred in Belgium). At around the same time shredded/chipped waste [[Tyres|tyres]] were starting to also be used in some cement kilns as a [[Waste Derived Fuel]] as both the solvent based wastes and tyres had a high [[CV]] and attracted an income from taking them into a cement kiln. '''By 1998''' the MPA reports that 446,511 tonnes of waste by-products were used as fuel and raw materials, accounting for 4% of cement production and the proportion of fuel comprising waste was 5.7%<ref name = ''ref1''/>.

'''In 1995''' there were 20 'cement factories' in the UK producing around 15 million tonnes a year of cement each year, with the cost of energy in the process representing 40 to 50% of running costs. There was a drive to substitute traditional fuels (coal and petroleum coke) with cheaper fuels slightly before this date, and trials were still running at this time with the ramifications of these trials captured in a Parliamentary Briefing Note<ref>[https://researchbriefings.files.parliament.uk/documents/POST-PN-60/POST-PN-60.pdf Parlimentary Briefing Note 60 April 1995]</ref>. [[Waste Derived Fuel]] had already started to play a more significant role in UK cement processing, in line with other countries (especially in Europe). It started with the use of solvent based hazardous wastes, often referred to as [[Cemfuel]] and by some as a [[Recycled Liquid Fuel]] ([[RLF]]), which was being trialed at a substitution of 50% of traditional coal fuel (although at the time 100% substitution occurred in Belgium). At around the same time shredded/chipped waste [[Tyres|tyres]] were starting to also be used in some cement kilns as a [[Waste Derived Fuel]] as both the solvent based wastes and tyres had a high [[CV]] and attracted an income from taking them into a cement kiln. '''By 1998''' the Mineral Products Association (MPA) reports that 446,511 tonnes of waste by-products were used as fuel and raw materials, accounting for 4% of cement production and the proportion of fuel comprising waste was 5.7%<ref name = ''ref1''/>.

Cement kilns are an option for disposing of hazardous materials because: