Cement industry

Alternative fuels for cement plants

Kiln performance comes first. Supply begins with the plant’s permitted feed points, handling system, quality limits and operating objectives—not a generic RDF or SRF label.

Prepared solid recovered fuel moving through an enclosed processing line

Co-processing is a plant-specific engineering decision

Cement kilns can use suitably prepared residual material as part of their thermal input. The relevant measure is thermal substitution rate: the share of thermal energy supplied by alternative fuels, not the share by mass.

A suitable route depends on where material enters the process, the combustion environment, the kiln and preheater configuration, clinker chemistry and the site’s environmental permit. A specification that works at one plant is not automatically transferable to another.

RDF, SRF and the receiving specification

RDF is a broad commercial description. SRF is prepared and classified under a defined framework, but an SRF class is not the complete purchasing specification. The receiving cement plant still needs limits and procedures for parameters relevant to its process.

See the SRF supply approach, or read the EN ISO 21640 classification guide.

Carbon claims require measured inputs

Replacing part of a coal input with RDF does not make the whole process carbon neutral. Fossil CO₂ impact depends on energy substitution, the RDF’s fossil and verified biogenic carbon fractions, and the accounting framework applied by the plant.

Compare coal and RDF in cement kilns without a blanket low-carbon claim.

Decision criteria

A workable supply starts at the kiln, then works back to the producer.

Factor	Why it matters	Confirm before supply
Thermal input	Mass does not show how much conventional energy input can be displaced.	Net calorific value, variability and the plant’s thermal substitution objective.
Chemistry	Chlorine, ash and trace elements can affect kiln operation, bypass demand and clinker chemistry.	Plant-specific limits, sampling method and response to an out-of-spec result.
Physical form	Feed point and dosing equipment determine acceptable particle size, density and presentation.	Preparation method, particle-size distribution, storage and feeding compatibility.
Permit and monitoring	Co-processing remains subject to the plant’s permit and emissions controls.	Permitted material, acceptance procedure, documentation and monitoring responsibilities.

Sources and further reading

General market information only. Requirements must be confirmed for each material, route, permit and receiving operation.

Define the route

Start with the receiving specification and the material that must meet it.

Discuss a cement-plant requirement →