Boilers and Heat Recovery for Waste-to-Energy Plants

In waste-to-energy (WTE) facilities, thermal recovery is at the heart of the process for converting municipal or industrial waste into process steam or electrical energy. However, waste combustion generates a highly aggressive gaseous environment: high levels of sticky fly ash, variability in the Lower Heating Value (LHV), and high concentrations of corrosive contaminants such as hydrochloric acid (), sulfur-containing compounds, and alkali salts.

AITESA designs, manufactures, and integrates highly reliable thermal solutions for the WtE sector: heat recovery boilers (WHRU), economizers, radiation/convection evaporator fins, and heat exchangers for integration into steam cycles or combined-cycle systems.

Our technologies make it possible to maximize plant production, adapt equipment to changes in waste types, prevent chloride-accelerated corrosion, and extend operational availability between maintenance shutdowns.

Do you have a thermal project at a waste-to-energy plant? Tell us about the combustion conditions, gases, or equipment involved.

Challenges Faced by Waste-to-Energy Plants

The design of a recovery system in a WtE plant requires a preventive strategy to combat premature deterioration of heat exchange surfaces. The boiler’s operational reliability depends on the active management of complex mechanical and chemical processes:

• Corrosion due to chlorine content at high temperatures: Corrosion caused by molten chlorine and chlorides in superheater/reheater tubes and evaporators requires the selection of advanced alloys or protective coatings (Inconel cladding).

• Fouling and Slagging: Deposition of low-melting-point fly ash that forms insulating deposits in the convective passes, increasing the thermal resistance and pressure drop () of the flue gas circuit.

• Particle abrasion erosion: Continuous transport of suspended solid particles that wear down the tube bundles. This requires optimizing gas flow velocities and selecting smooth-tube geometries or physical protective measures.

• Automatic cleaning systems and maintainability: Mandatory integration of continuous cleaning systems (steam/air soot blowers, mechanical hammering, or shock wave cleaning) to keep the gas passages clean without unscheduled shutdowns.

AITESA provides services ranging from the conceptual engineering phase through to supply, revamping, or turnkey EPC projects. We redesign gas passages, convection passages, and tube layouts to ensure efficient heat transfer and protection against corrosion.

Why Choose AITESA for Waste-to-Energy?

With more than 40 years of experience in the design and integration of thermal equipment in corrosive and particulate-laden environments, AITESA offers proven technical expertise:

• Specialization in WtE Boiler Revamping: Proven experience in the replacement and redesign of critical modules (evaporator coils, economizers) to adapt existing boilers to increases in the calorific value of the waste or increases in treatment capacity.

• Expertise in protective materials and techniques: Extensive expertise in specifying metallurgical compositions resistant to thermal shock and halogen corrosion.

• EPC Capabilities and Downtime Risk Mitigation: We provide integrated management of engineering, in-house manufacturing, NDT testing, assembly, and the integration of control and cleaning systems, ensuring strict adherence to the plant’s downtime windows.

AITESA has participated in revamping, heat recovery, and thermal equipment projects at waste-to-energy plants, where the adaptation of boilers and auxiliary equipment is critical to maintaining performance, safety, and availability in the face of changes in waste composition or operating conditions.

Success stories

Revamping of a boiler in a Waste-to-Energy plant in Tarragona

AITESA Contenido | Success stories - waste-to-energy | No Comments

The increase in the calorific value of municipal waste has posed a challenge for the waste-to-energy plants, since it implies a higher heat input in the incineration furnaces, exceeding the…

Do you need to recover heat or upgrade thermal equipment at a waste-to-energy plant?
Please briefly describe your needs, the equipment involved, or the operating conditions. Our technical team will review the initial information and advise you on the most appropriate solution.