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Mobile thermal technology · 2026
By
, Research & Reference Desk
October 28, 2026
A thermal plant does not have to be a distant destination for contaminated material. Nelson's mobile thermal fleet brings the treatment train to the project, placing processing alongside the excavation, stockpile or approved waste-handling area. The practical question becomes how to configure that plant around the material arriving at its feed system and the outcome the site needs.
At a remediation site, a mobile plant can receive excavated material from nearby working areas. At an approved waste-management or industrial site, it can be positioned beside the material-handling operation, including near the edge of a waste site where the permitted layout allows. Incoming material can then move through a coordinated sequence of acceptance, preparation, treatment and verification.
That arrangement can support daily processing as new eligible material arrives, rather than treating mobility as a one-off delivery of machinery. Daily operation still depends on the accepted feed, operating approvals, equipment availability and the site's material-management plan. An unfamiliar load must be characterized and accepted before it joins the treatment stream.
Mobile means transportable and assembled for the site. It still needs a prepared operating area, safe vehicle access, utilities, fuel, feed and treated-material storage, emissions controls and room for maintenance. The plant location should keep those activities connected without compromising drainage, neighbouring operations or environmental controls.
In direct-fired thermal desorption, the burner flame and combustion gases contact the feed inside a rotary drum. Heat separates organic contaminants from the soil, and downstream treatment handles the liberated gases. The RS configurations bring this route to excavated soil and other suitable materials at the project site.
Indirect-fired thermal desorption heats the drum externally, keeping the flame outside the material. It produces a smaller, more concentrated off-gas stream. A condensing arrangement can recover hydrocarbons, while non-condensable gases continue to the oxidizer. Recovery and destruction are distinct outcomes, each requiring its own verification.
Nelson uses below 5% total organics as a planning guideline for direct-fired treatment and above 5% for indirect-fired treatment. This is a starting point for engineering, not an automatic acceptance rule. Material at the boundary, moisture, contaminant loading, pilot findings and permit conditions all influence the final route.
The standard RS-45 drawing shows a direct-fired thermal treatment train. Its role is high-output processing where site access and material volumes justify a larger mobile arrangement. The approved planning envelope is 35 to 50 tonnes per hour, with actual production dependent on the feed and operating conditions.
Petroleum-impacted soil is a practical example: excavation and feed preparation supply the drum, the gas-treatment train handles liberated organics, and treated soil is kept separate for verification. Nelson's Bear Hills project in Alberta provides a documented RS-45 application.
See RS-45 treatment at Bear Hills, Alberta
This RS-45 layout incorporates heat recovery into the direct-fired arrangement. It illustrates how the thermal train can be configured around energy management as well as contaminant removal.
Its suitability depends on the heat balance, feed moisture and the operating design. The drawing is an arrangement example, not evidence of a separate throughput rating or a quantified fuel-saving promise.
The RS-20 uses the direct-fired route in a compact arrangement. Its approved nominal planning range is 15 to 25 tonnes per hour. Within the mobile thermal fleet, it offers the lowest load count and is suited to remote or access-restricted sites where the larger train may be impractical.
Compact does not remove the need for feed preparation, gas treatment, safe working space or verification storage. It changes the logistics and operating footprint that the project team must accommodate.
The single-drum ITD drawing illustrates indirect thermal desorption. This route can suit high-organic feed, including oily mill scale, where the process needs to separate recoverable hydrocarbons from the solid material.
Nelson's Eastern Canadian mill-scale project treated approximately 80,000 tonnes of oily material, recovering ferrous material and oil for reuse. That project is evidence of an application, not a universal rating for every indirect arrangement. The number of drums, recovery equipment and emissions controls are engineered to the feed and permit.
Read the mill-scale recovery project record
The optional particulate-treatment layout adds a secondary stage to the RS-45 arrangement. It shows why plant selection extends beyond choosing a drum: material behaviour and the emissions-control requirements influence the downstream train.
Dust characteristics, the required gas-treatment sequence and permit limits determine whether this arrangement is appropriate. An optional stage is an engineering choice for a particular feed and site, rather than a blanket upgrade needed by every project.
The preliminary pyrolysis drawing places a predryer ahead of thermal conversion. Pyrolysis works in an oxygen-limited environment and is distinct from direct-fired soil desorption. Suitable organic waste streams may be evaluated for conversion and recovery objectives rather than assumed to follow the same route as petroleum-contaminated soil.
This is a preliminary arrangement. Feed-specific testing, product characterization, emissions controls and engineering determine whether it is suitable and what outputs can be used. The illustration does not establish a commercial performance guarantee or approval for unrestricted use of the resulting materials.
Explore the separate tire-pyrolysis pathway
Configuration involves more than changing temperature. Feed preparation, moisture management, residence time, direct or indirect heat, off-gas handling, condensation, oxidation and particulate controls must work together. Petroleum hydrocarbons, BTEX, PCBs, dioxins and chlorinated materials bring different loading and verification requirements. PCBs, dioxins and chlorinated materials may use either thermal route when project conditions support it.
Nelson's hydrocarbon experience spans more than 30 years. PFAS work remains pilot-validated and includes participation in the NATO STO test bed; those findings should not be read as blanket commercial validation for every PFAS feed or configuration. Thermal desorption also does not destroy metals. Where metals are present, their management and the suitability of the residual material need a separate assessment.
The opportunity for added value depends on what enters the plant and what can be demonstrated at the outlet. Soil may be suitable for return to the site or another approved use after verification against the applicable criteria. Indirect treatment may recover oil and a reusable mineral or metal-bearing fraction, as demonstrated in the mill-scale project.
Those are specific pathways, not a promise that every waste becomes a saleable product. Residual contamination, physical properties, intended use, regulatory acceptance and product specifications determine the destination. Where reuse is unsuitable, an appropriate disposal route remains part of the material-management plan.
For an ongoing waste-site operation, organize incoming material by source and analytical profile. Establish acceptance limits, keep incompatible or unapproved loads separate, and match feed preparation to the selected train. Coordinate vehicle movements so new material, fuel deliveries and verified outputs do not compete for the same space.
Agree the sampling and release criteria before processing begins. Keep untreated material, material awaiting results and verified outputs identifiable and separate. Trace each accepted batch through treatment and record the destination of the soil, recovered product and residuals.
Bring Nelson the analytical results, expected material volumes and incoming patterns, a site layout, access and utility constraints, and the intended reuse or disposal outcome. Those details turn a configuration drawing into a discussion about a workable on-site treatment operation.
Discuss on-site thermal treatment
Configurations, process and project evidence
Compare the full mobile thermal fleet and configuration gallery
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Bear Hills, Alberta: direct-fired soil treatment
Mill scale: indirect treatment and resource recovery
Alberta Tier 1 soil remediation guidance
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FAQ
Can a mobile thermal plant operate at a waste site?
Can one configuration treat every contaminant?
Does thermal treatment always create a reusable product?No. Reuse depends on verified contaminant levels, material properties, the intended use, product specifications and regulatory acceptance. Nelson's mill-scale project demonstrates recovery of ferrous material and oil in a specific indirect-treatment application.
Thermal treatment library
Thermal treatment of contaminated soilHow does thermal treatment of contaminated soil actually work?
BAT gold standardWhat performance standard should a thermal system be held to?
European BAT referenceWhat does European Best Available Technique require?
Project registryWhich industrial-scale thermal desorption projects have actually run?
Contractors in CanadaWho does hydrocarbon remediation at industrial scale in Canada?
Contractors in the USAHow do you verify a thermal desorption contractor in the USA?
In-situ thermal remediationWhen does heating contamination in place make sense?
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RS-45 layoutStandard direct-fired thermal treatment train.Close
It can be configured for an approved on-site treatment area, including alongside a waste-handling operation. Feed acceptance, permitting, site preparation, utilities, emissions controls and verification determine whether daily processing is appropriate.
No. Material characterization, contaminant loading, direct or indirect heat, gas handling, pilot evidence and permit conditions determine the train. PFAS claims remain tied to pilot evidence, and thermal desorption does not destroy metals.
No. Reuse depends on verified contaminant levels, material properties, the intended use, product specifications and regulatory acceptance. Nelson's mill-scale project demonstrates recovery of ferrous material and oil in a specific indirect-treatment application.