How cement kilns use alternative fuel: co-processing explained
A cement kiln is one of the few industrial processes that can take a waste derived fuel and leave nothing behind. That is why it is the natural customer for a plant like AERC.
What co-processing means
Co-processing is the term the industry uses for introducing alternative fuels and raw materials into a standard cement production process in place of conventional fuels and raw materials. CEMBUREAU describes it as the combination of simultaneous material recycling and energy recovery from waste in one thermal process: the heat value of the waste fuel replaces fossil fuel, and the ash is incorporated as a partial replacement of raw material, leaving no waste residue.
Why a kiln suits it
The WBCSD Cement Sustainability Initiative guidelines put it this way: a cement kiln producing clinker is, by its nature, an efficient tool for the recovery of minerals and energy from waste. The kiln allows complete burn out of a waste derived fuel, and the ashes are captured in the clinker, replacing some of the mineral components. Testing cited in the guidelines found cement made with co-processed waste exhibits the same physical and chemical properties. In the waste hierarchy the guidelines place co-processing above landfill and above incineration, because both the energy and the material are recovered.
How far it has gone
According to CEMBUREAU, the use of alternative fuels in the European cement industry began over 30 years ago, in 1990, and several plants now operate at 90 to 100% substitution. Typical fuels include solid recovered fuel and refuse derived fuel, end of life tyres, animal meal, sewage sludge, wood and paper waste and sawdust. The association also notes that air emissions would not be lower if kilns relied only on fossil fuels; they vary regardless of the fuel.
What the kiln asks the supplier
A kiln operator buys a specification, and the Adelaide review of the field names the questions behind it: will the fuel perform consistently, will it meet environmental requirements, and will it support safe and reliable production. In practice that becomes a data sheet: energy value, moisture, particle size, ash and chlorine, measured and repeated. The WBCSD guidelines describe the plant giving its waste generators a clear specification for the alternative fuel it can use. AERC's fuel data sheet template is laid out around those questions.
What it means for AERC
The plant is designed to supply refuse derived fuel to cement kilns and industrial users under long term supply agreements, replacing part of the coal they burn. No contract is signed yet; off takers are one of the four seats open. The off taker seat.
General information, checked 14 November 2026. Figures are quoted from the sources listed at the end; the source in force prevails. AERC is at concept stage: nothing here is an offer of securities or a promise of returns.