EfW Boiler Inspection at Enfinium Kemsley, Gas Pass 1 and 2 Drone Surveys During Planned Outages

Confined space drone technology supporting slag assessment, refractory verification and boiler optimisation in Energy from Waste operations.

Over a two week period, DJM Aerial Solutions undertook comprehensive visual inspections of Gas Pass 1 and Gas Pass 2 across Boiler Lines 1 and 2 at Enfinium Kemsley Energy from Waste facility, supporting the site’s planned outage schedule.

The purpose of these inspections was to provide high resolution internal condition data to assist Martin GmbH, the boiler manufacturer, in assessing slag accumulation, evaluating cleaning system performance, and identifying opportunities to optimise boiler efficiency.

Using the Elios 3 confined space drone, we delivered detailed internal inspection footage without the need for manned entry, scaffold erection, or prolonged downtime.

Scope of Works, Gas Pass 1 and 2 Visual Inspection

The inspection programme focused on slag build up assessment within Gas Pass 1, evaluation of deposition patterns along combustion pathways, inspection of Gas Pass 2 tube banks for slag accumulation, analysis of cleaning system performance effectiveness, verification of refractory lining condition, identification of exposed boiler tubes, and assessment of structural steel supports and framework integrity.

Each boiler line was inspected during its respective outage window, ensuring minimal disruption to site operations while maximising inspection coverage.

Why Slag Build Up Monitoring Matters in EfW and Biomass Boilers

In Energy from Waste and biomass plants, slag formation is a continual operational challenge. Slag deposits can restrict gas flow and reduce heat transfer efficiency, increase thermal stress on tube banks, lead to premature refractory degradation, reduce boiler efficiency and increase fuel consumption, and contribute to unplanned outages if left unmanaged.

By capturing clear visual data from within Gas Pass 1 and 2, Martin engineers were able to assess the severity and distribution of slag build up and evaluate whether cleaning systems were performing optimally. This inspection data is critical for fine tuning combustion parameters, soot blower sequencing, and maintenance intervals.

Inspection of Tube Banks and Cleaning Efficiency

Within Gas Pass 2, particular attention was given to slag formation around superheater and economiser tube banks, evidence of uneven cleaning or shielded zones, areas where ash deposition suggested cleaning system inefficiency, and signs of erosion or tube exposure beneath refractory zones.

The ability to fly directly along tube banks using the Elios 3 allowed engineers to gain perspectives that are often difficult to achieve via scaffold platforms or manned access.

Refractory and Structural Condition Verification

Alongside slag assessment, we conducted a thorough review of refractory spalling or cracking, delamination or material loss, areas of exposed steelwork or tubes, distorted supports or bracketry, and early signs of structural fatigue.

High resolution stabilised footage ensured that even minor defects were recorded for engineering review and maintenance planning.

The Role of Confined Space Drone Technology in EfW Boiler Inspection

Traditional inspection of boiler gas passes typically involves extensive internal scaffolding, multiple confined space entry teams, rescue teams on standby, extended outage windows, elevated cost, and increased safety risk.

By contrast, our confined space drone inspection methodology provides enhanced safety, improved efficiency, greater inspection accuracy, and significant cost savings.

From a safety perspective, there is zero manned entry into hazardous confined spaces, reduced exposure to heat stress and residual contaminants, and no requirement for personnel to work at height within the boiler chamber.

From an efficiency standpoint, inspections are rapidly deployed, outage duration is reduced, and engineers receive immediate visual feedback while on site.

From an accuracy perspective, the Elios 3 provides high resolution 4K footage, close proximity inspection of tube banks and refractory surfaces, and repeatable inspection routes for year on year comparison.

From a cost perspective, scaffold build and dismantling is eliminated, labour requirements are reduced, and downtime related revenue loss is minimised.

Benefits for Energy from Waste, Biomass and Power Generation Operators

Confined space drone inspection within boilers supports improved outage planning, data driven optimisation of cleaning systems, early identification of integrity concerns, enhanced collaboration with OEM manufacturers, compliance with Written Schemes of Examination and asset integrity programmes, and reduced operational risk exposure.

For EfW, biomass, and other power generation facilities, these inspections provide valuable insight into internal asset condition while maintaining the highest safety standards.