Containerized thermal treatment method for contaminated soils and waste containing PFAS and similar contaminants

Abstract

The invention relates to a containerized method for the thermal treatment of contaminated solids, pasteous materials, and waste. The system comprises at least one thermally insulated container designed to minimize heat loss and enable material loading from a liftable top panel or a side panel, as well as at least one heat production unit featuring a burner control system and a combustion chamber capable of achieving oxidizing conditions for the complete destruction of contaminants. The method provides simultaneous thermal treatment of materials and vapor-phase contaminant destruction, supported by a ventilation system and a monitoring system for real-time adjustments. In a second aspect, the invention provides a containerized device with comparable operational features, designed for portability and modular deployment, facilitating on-site remediation in remote locations.

Description

[0001] CONTAINERIZED THERMAL TREATMENT METHOD FOR CONTAMINATED

[0002] SOILS AND WASTE CONTAINING PFAS AND SIMILAR CONTAMINANTS

[0003] FIELD OF THE INVENTION

[0004] The present invention relates to a containerized method for the thermal remediation of contaminated soils, sludge, and waste. It employs Thermal Conductive Heating (TCH) and in-situ vapor-phase oxidation for the treatment and destruction of a wide range of contaminants, including but not limited to per- and polyfluoroalkyl substances (PFAS), dioxins, polychlorinated biphenyls (PCBs) and chlorinated solvents.

[0005] BACKGROUND OF THE INVENTION

[0006] The remediation of contaminated soils and waste remains a significant challenge due to the chemical stability and toxicity of many pollutants. Persistent Organic Pollutants (POPs), including PFAS, dioxins, PCBs, pesticides and certain chlorinated solvents, present long-term risks to human health and the environment. Conventional remediation methods, such as landfill disposal and incineration, often fail to provide sustainable or efficient solutions.

[0007] Thermal treatment technologies, particularly Thermal Conductive Heating (TCH), have proven effective in mobilizing contaminants by elevating materials to target temperatures. However, existing approaches often produce vapor-phase contaminants that require additional treatment, increasing complexity and waste. The present invention addresses these limitations by integrating soil heating with in- situ vapor oxidation within a portable, scalable containerized system.

[0008] Thermal desorption efficiently removes contaminants with boiling points below 550°C under standard atmospheric pressure, including organic pollutants and select inorganics like cyanides and mercury. TCH, a method within thermal desorption, transfers thermal energy radially through heating elements in contact with contaminated materials. This approach offers advantages over methods such as resistive electric heating or steam injection, achieving soil temperatures of 350- 500°C. It is effective in both ex-situ and in-situ applications, making it suitable for confined spaces, remote locations, and urban sites while reducing soil handling and transportation requirements. Thermal desorption often incorporates vacuum-assisted processes to extract volatile contaminants. These systems apply suction to draw air and vapor from the subsurface, concentrating pollutants for removal or destruction. Although effective, these systems face challenges with fuel and / or energy efficiency and uniform heating due to soil heterogeneity, including variations in moisture and pollutant concentrations. This unevenness complicates thermal treatment and necessitates precise control to ensure performance.

[0009] PFAS and similar organic contaminants, often resulting from industrial and military activities, pose unique challenges due to their high chemical and thermal stability. Traditional remediation methods, such as bioremediation and soil washing, are frequently inadequate, while thermal desorption generates contaminated vapors requiring extensive secondary treatment. These methods may accumulate the pollutant in other matrices, like activated carbon, or capture it in liquid or solid form following the condensation of vapors. This results in waste products that require further processing for proper disposal.

[0010] The present invention overcomes these challenges by combining TCH with direct thermal oxidation at high temperatures and residence time in a containerized system. This integration minimizes waste generation, enhances treatment efficiency, and reduces operational costs and carbon footprint, offering a comprehensive and sustainable solution to soil remediation. This integration may furthermore reduce the size of the necessary equipment.

[0011] SUMMARY OF THE INVENTION

[0012] The present invention and embodiments thereof serve to provide a solution to one or more of above-mentioned disadvantages. To this end, the present invention relates to a system and methods which combines improving the heating efficiency and adaptability as well as thermal destruction of vaporized contaminants in the same device.

[0013] This invention provides a containerized thermal treatment system for contaminated soils with PFAS or other persistent organics contaminants. The system utilizes Thermal Conductive Heating (TCH) to heat the soil to temperatures up to 350- 450°C, effectively mobilizing the contaminants into the vapor phase. The vaporized contaminants are then directed into a high-efficiency burner system, designed to oxidize those contaminants at temperatures exceeding l,400°C with optimized residence time and turbulence.

[0014] Key features of the invention include:

[0015] • Compact Design: A standard 20" or 40" container modular system capable of treating up any quantities of soil per batch, given its modularity.

[0016] • Integrated Oxidation System: Burners that serve dual purposes of soil heating and vapor destruction.

[0017] • High Efficiency: Achieves near-total PFAS and other organics' destruction, converting them into byproducts such as CO2, H2O, HCI, HBr NO2, SO2, NO3 and HF as well as other harmless compounds.

[0018] • Environmental Sustainability: Eliminates the need for external Vapor Treatment Units (VTU), significantly reducing waste, the overall size of the system, and energy use.

[0019] The system's modular design allows for scalability and portability, enabling deployment in remote or urban sites as well as large industrial with minimal setup time. The system may be inherently modular, allowing multiple containerized units to be deployed simultaneously for large-scale remediation projects. Containers can be daisy-chained or operated in parallel, with centralized or distributed control systems depending on site conditions. This architecture supports rapid scale-up without requiring permanent infrastructure.

[0020] DETAILED DESCRIPTION OF THE INVENTION

[0021] The terms "contaminated soil" and "contaminated material" are used here as synonyms and should be understood to include all types of soil, sludge or other materials that may be contaminated with any cocktail of pollutants, such as organic contaminants, e.g. hydrocarbons, and inorganic contaminants, with a boiling point at atmospheric pressure of 550°C or more and / or heavy metals.

[0022] Conductive heat occurs when two materials or material objects are in direct contact and the temperature of one is higher than the temperature of the other. Thermal conduction is the transfer of kinetic energy from the warmer medium to the colder one. The term "conduction" as used herein is therefore intended to refer to all types of heat transfer in which heat is moved from one (warmer) object to another (colder) object by direct contact. It should be understood that in the present invention, when heat transfer by conduction is mentioned, also a small amount of heat is usually also transferred to the soil through convection (fluid movement) and radiation.

[0023] The term "remote flame" refers to the movement of the combustion chamber, burner head, and thus the flame, inside the heating tube (inside the soil) rather than outside the soil as is the case with the conventional system.

[0024] Description of the container

[0025] The containerized thermal treatment system is designed to house and process contaminated soil efficiently while maintaining a compact and modular design. The soil is stored within a thermally insulated compartment, defined by right insulation panel (2) and left insulation panel (3), which provide lateral thermal containment. The top insulated panel (5) and the insulated doors (4) complete the enclosure, ensuring minimal heat loss and external contamination. The ground level thermal insulation (32) further reduces heat dispersion. An opening panel at the top of the container (6) facilitates loading the contaminated material (1), while slots for liquid collection (7) and slots for vapor collection (8) allow for efficient extraction of byproducts during the treatment process.

[0026] The heating elements, comprising combustion chambers (9) and heating plates (10), are integrated into the container, transferring heat directly to the soil. The thermal energy is delivered uniformly through a network of inner heating tubes (9) surrounded by heat exchange volumes (33). The combustion chambers (9) can be adjusted for depth using sleeves (17) and threads (15), ensuring targeted heating to areas with higher moisture or contaminant concentrations.

[0027] The fan extractor (22) and air intake valve (12) regulate airflow for combustion, ensuring optimal oxygen levels for efficient heating and contaminant destruction. Combustion gases are expelled via the exit of combustion gases (11), while preheated air and reburn vapors are reintroduced into the system for enhanced energy efficiency.

[0028] At the container's rear, doors (26) provide access for maintenance, loading and unloading treated soil. Additionally, a container extension (25) enables flexibility in accommodating larger treatment batches or additional equipment as needed. The burner control box (31), combined with monitoring systems, allows precise adjustments of heat, pressure, and vapor flow. For liquid fuel burners, the metal coil for fuel preheating (19) ensures combustion efficiency by preheating fuel before it reaches the fuel injector (20). A flame detection probe or photoelectric sensor (27) and electric igniter or resistor igniter (28) ensure reliable and safe operation throughout the process.

[0029] This robust and adaptable container system ensures efficient remediation of contaminated soils while minimizing environmental impact and operational complexity. The control system may include temperature sensors embedded in the soil, pressure transducers in the vapor ducts, and / or gas analyzers in the exhaust flow. These may all be interconnected via a central control logic that allows for remote monitoring, safety interlocks, and feedback control of the heating and combustion process.

[0030] According to a further or another embodiment, the containerized thermal treatment system comprises a plurality of specialized heating elements, each constructed with concentric tubes. According to some embodiments, an external tube is formed from stainless steel, more preferably having a semi-cylindrical cross-section welded to a structural steel plate having a thickness of between 5 mm to 15 mm. According to some embodiments, an internal tube is concentrically arranged within the external tube and is likewise formed from stainless steel. Preferably, said external tube is internally lined with a refractory cement layer. More preferably, said refractory cement layer has a thickness of between 5 and 20 mm. This refractory lining serves to maintain the high internal temperature while protecting the structural integrity of the heating tube.

[0031] According to a further or another embodiment, the internal tube of the heating element may have various lengths ranging from 3 to 25 meters, with said length being preferably determined based on the overall dimensions of the container and the volume of contaminated material to be treated. The length of the internal tube may be adjusted to ensure sufficient residence time for combustion gases while maintaining optimal thermal distribution throughout the soil matrix.

[0032] According to some embodiments, the internal tube is sealed at one end and provided at the opposite end with a vapor and gas handling assembly comprising connection collars and flanges. In a particularly advantageous arrangement, the internal tube features multiple rectangular openings spaced along its length, positioned to allow combustion gases to escape into the external volume and promote uniform heat transfer across the soil matrix.

[0033] According to a further or another embodiment, the internal tube may comprise multiple rectangular openings spaced along its length, with said openings being strategically positioned to allow a controlled portion of the combustion gases to escape into the external volume between the internal and external tubes. These openings may facilitate a more balanced energy transfer to the soil compared to configurations wherein all combustion gases are directed to the distal end of the internal tube before returning through the external volume.

[0034] According to a further or another embodiment, the multiple rectangular openings in the internal tube may be specifically dimensioned and positioned based on computational fluid dynamics modeling to create a partial flow pattern of very hot gases into the heat exchange volume. This configuration may produce a more homogeneous temperature profile across the entire outer metallic surface, thereby facilitating uniform heating of the contaminated material. The dimensions, spacing, and angular orientation of said openings may be determined according to the specific thermal conductivity properties of the refractory cement lining, the desired temperature profile, and the characteristics of the contaminated material being treated.

[0035] According to a further or another embodiment, the partially perforated internal tube with strategically positioned openings may significantly improve the thermal efficiency and operational safety of the system. By enabling a calculated distribution of combustion gases at various points along the heating element rather than exclusively at its distal end, the system may achieve more precise temperature control, reduced thermal stress on structural components, extended operational lifespan, and enhanced treatment uniformity across the entire volume of contaminated material.

[0036] According to a further or another embodiment, the rectangular openings in the internal tube may vary in size and frequency along the length of the tube, with larger or more numerous openings positioned toward the distal end of the tube to compensate for the progressive cooling of combustion gases as they travel through the refractory-lined internal tube. This graduated arrangement of openings may further enhance the uniformity of heat distribution and may ensure that the entire volume of soil receives adequate thermal treatment despite variations in distance from the burner assembly.

[0037] According to a further or another embodiment, the system may be adaptable to adjust the configuration of the openings in the internal tube based on the specific characteristics of the contaminated material being treated. For materials with higher moisture content or greater thermal conductivity variations, the arrangement and dimensions of the openings may be modified to deliver targeted heating to areas requiring enhanced thermal input, thereby optimizing treatment efficiency while maintaining the structural integrity of the heating elements.

[0038] According to some embodiments, the combustion gases generated within each heating element are constrained to flow through the refractory-lined internal tube for a minimum residence time of at least 1 second, preferably of at least 1,5 seconds, at a temperature of at least 1400 °C before being discharged into the container volume through the strategically positioned openings. This controlled residence time ensures that volatile organic contaminants, particularly persistent substances such as PFAS, undergo sufficient exposure to high-temperature oxidative conditions to achieve near-complete destruction prior to gas release.

[0039] In a preferred embodiment, the refractory cement lining the internal tube exhibits the following properties: a density between 1100 kg / m3and 2000 kg / m3, a specific heat capacity between 800 J / kg / K and 1000 J / kg / K, and a thermal conductivity between 0,37 W / mK and 0,4 W / mK. These thermal properties optimize heat retention within the internal tube, enhance combustion stability, and protect the mechanical integrity of the heating element during prolonged high-temperature operation.

[0040] The internal tube with refractory lining represents a significant advancement in thermal remediation efficiency. While conventional PFAS destruction systems potentially require up to 40 to 80 % additional energy beyond soil heating, the several embodiments as described herein achieve both soil heating and complete PFAS destruction with substantially the same energy input. This may be accomplished through the refractory-lined internal tube which maintains the high temperatures beneficial for PFAS mineralization while directing thermal energy through the heat exchange volume to efficiently heat the surrounding soil. According to some embodiments, the vapor collection and combustion system is structurally integrated with the heating elements. A vapor inlet compartment is provided adjacent to the heating element, comprising dedicated flanged connections for introducing vapor streams into the flame core of the burner. A separate air supply compartment, which is flange-connected, delivers combustion air to the burner, facilitating controlled oxygen supply and optimized flame dynamics. Preferably, the burner head is coupled to the air supply chamber via a standardized flange assembly, ensuring secure, leak-free operation under high-temperature conditions.

[0041] According to some embodiments, the heating elements may be assembled in a predefined sequence to ensure mechanical stability and gas-tightness. The internal tube is first inserted into the external tube, with careful alignment of the rectangular gas outlet openings. Subsequently, the vapor inlet chamber, burner tube, air supply chamber, and burner head are installed in succession using bolted flanges. All junctions are sealed, preferably with high-temperature-resistant teflon gaskets, to prevent gas leakage during operation. The orientation of the openings is advantageous to achieving optimal thermal distribution, and assembly protocols specify precise angular alignment relative to the container structure.

[0042] According to some embodiments, the thermal performance of the system has been validated through numerical simulations. Results demonstrate that, under standard operational conditions (propane combustion at approximately 0.44 kg / h per heating element and an air flow rate of 14 kg / h), the system is capable of elevating the soil temperature to between 350 °C and 450 °C within 20 operational days, even for soils containing up to 20 % water by weight. The gas velocity profile within the internal tubes confirms sufficient residence time, while temperature distribution analyses reveal homogenous heating across the treated volume.

[0043] Burners

[0044] The burners in the containerized thermal treatment system are an advantageous innovation designed to achieve efficient heating and near-total destruction of contaminants, including challenging compounds such as PFAS, dioxins, pesticides, PCB or similar long-chain organic contaminants. These burners combine primary combustion with an integrated reburn system, ensuring high temperatures, extended residence time, and optimized turbulence for complete thermal oxidation of contaminants. Primary Combustion Chamber: The burners are equipped with a combustion chamber (9) located within the heat exchange volume (32). This chamber generates the initial flame using either gaseous or liquid fuels, such as diesel, biodiesel, natural gas, biogas or other fuels which are preheated through a metal coil (19) to enhance combustion efficiency. The combustion chamber is thermally insulated with refractory cement (13) to ensure consistent high temperatures and minimize heat loss. Reburn System: The system incorporates a reburn flexible line (16) that redirects partially combusted gases and unburned contaminants back into the burner. This mechanism facilitates secondary combustion at temperatures exceeding l,400°C, further breaking down persistent organic pollutants into byproducts like CO2, H2O, NO2, NO3, HF, HCI, HBr and other harmless byproducts. The reburn process ensures thorough oxidation while minimizing secondary emissions. Extended Combustion Chamber: To achieve the required residence time of at least 1 second, preferably at least 2 seconds, the burners feature an extended combustion chamber design. This elongated chamber allows the contaminants in the vapor phase to remain exposed to high temperatures for a sufficient duration, ensuring complete thermal destruction. The chamber is equipped with precise airflow controls, including the air intake valve (12) and fan extractor (22), to maintain the ideal oxygen levels for combustion. Turbulence Generation: Within the extended combustion chamber, optimized turbulence is generated by a combination of airflow patterns and the chamber's geometry. The controlled turbulence ensures thorough mixing of the vaporized contaminants with oxygen, maximizing the efficiency of the oxidation process. This feature is advantageous for breaking down complex chemical structures like those of PFAS and other persistent organic pollutants. Monitoring and Control: Real-time monitoring of temperature, pressure, and gas composition is facilitated by the burner control box (31) and integrated sensors, including a flame detection probe or photoelectric sensor (27). These systems ensure precise control of combustion parameters, enabling consistent performance across varying soil and contaminant profiles. Environmental Efficiency: The burners eliminate the need for external vapor treatment units by integrating heating and vapor destruction into a single system. This design significantly reduces waste generation, energy consumption, and operational complexity, making the system both environmentally sustainable and cost-effective. In summary, the burners' advanced design, combining a primary combustion chamber, reburn system, extended chamber for residence time, and turbulence generation, ensures efficient contaminant destruction with minimal environmental impact. Their adaptability to various fuels and contaminant profiles further enhances their versatility and effectiveness in soil and solid waste remediation applications.

[0045] Preferred Embodiment with Enriched Oxygen for Enhanced Combustion Efficiency

[0046] In a preferred embodiment, the system is configured to operate with burners that utilize enriched oxygen instead of primary air. This configuration is achieved by integrating an oxygen concentrator into the system. The oxygen concentrator separates atmospheric oxygen from nitrogen and other gases, supplying high-purity oxygen directly to the burners.

[0047] By using enriched oxygen, the total flow rate of combustion gases is significantly reduced while maintaining the same energy input. This reduction in flow has several key advantages:

[0048] 1. Increased Residence Time: The lower total flow rate within the combustion chamber (9) results in a substantial increase in the residence time of the vapor-phase contaminants. This extended exposure to high- temperature conditions ensures more thorough oxidation of PFAS and similar contaminants' molecules.

[0049] 2. Higher Temperatures: The enhanced combustion environment created by enriched oxygen allows for the achievement of much higher temperatures within the combustion chamber, exceeding the levels attainable with primary air. These elevated temperatures contribute to the system's ability to break down even the most thermally stable molecules, achieving near-complete destruction efficiency.

[0050] 3. Improved Destruction Efficiency: The combination of longer residence times and higher temperatures significantly enhances the destruction rate efficiency (DRE) of organic contaminants and other persistent contaminants. This improvement ensures compliance with the most stringent environmental standards for pollutant destruction. 4. Energy Optimization: The use of enriched oxygen reduces the volume of combustion gases, thereby minimizing energy losses during heat transfer and further optimizing the system's overall thermal efficiency.

[0051] The oxygen concentrator can be installed within the technical area of the front panel (24), integrating seamlessly with the existing infrastructure. This modular addition ensures operational flexibility, enabling the system to switch between primary air and enriched oxygen modes based on specific site or regulatory requirements.

[0052] This embodiment demonstrates the system's adaptability and its capability to achieve superior performance metrics in PFAS remediation, particularly in scenarios where enhanced destruction efficiency is advantageous. The enriched oxygen configuration further underscores the system's innovative approach to addressing complex environmental challenges with advanced thermal technologies

[0053] Catalytic oxidation

[0054] The catalytic oxidizers integrated into the containerized thermal treatment system serve as a final polishing step for the combustion gases. Positioned at the exit of combustion gases (11), these units are designed to ensure that any residual pollutants or unburned hydrocarbons remaining after the primary and secondary combustion processes are fully oxidized into harmless byproducts, such as carbon dioxide (CO2), water vapor (H2O), and traces of other products such as HBr, HF, HCI, NO2, NO3, etc.

[0055] 1. Purpose and Function: The catalytic oxidizers are advantageous for removing trace contaminants from the exhaust gases. Despite the high efficiency of the burners and reburn system, small amounts of volatile organic compounds (VOCs), semi-volatile organic compounds (SVOCs), and other byproducts may persist. The catalytic oxidizers chemically convert these compounds into benign substances through oxidation at lower temperatures than conventional thermal oxidation.

[0056] 2. Catalyst Composition: The catalytic oxidizers employ a matrix of high- surface-area materials coated with precious metal catalysts, such as platinum, palladium, or rhodium. These materials facilitate oxidation reactions by lowering the activation energy required for the process. This enables complete oxidation of residual pollutants at temperatures typically between 200°C and 700°C, preferably between 250°C and 600°C and most preferably between 300°C and 400°C significantly lower than those in the primary combustion chambers. In function of the type of contaminants, specific catalysts can be used, as the design allows for easy replacement of said catalysts.

[0057] 3. Process Description: o Gas Flow Control: Exhaust gases from the Heat Exchange volume (33) are routed through the catalytic oxidizers. The flow rate and temperature are carefully controlled to optimize contact time between the gases and the catalyst surface, ensuring effective treatment. o Oxidation Reactions: Residual VOCs and SVOCs are exposed to the catalyst, where they undergo chemical reactions with oxygen present in the exhaust stream. These reactions convert the pollutants into CO2 and H2O and trace elements, in compliance with emission limits. o Fluoride Management: In case of treatment of PFAS, trace levels of hydrogen fluoride (HF) produced during PFAS decomposition are also polished through sorption or reaction with specific coatings on the catalyst or downstream filtration.

[0058] 4. Efficiency: The catalytic oxidizers achieve near-complete destruction of remaining contaminants, with destruction efficiencies exceeding 99% for most target pollutants. This ensures that the system meets or exceeds stringent environmental emission standards.

[0059] 5. Integration and Design: The catalytic oxidizers are compact and integrated seamlessly into the system's exhaust line, minimizing additional space requirements. They are constructed with durable materials to withstand the elevated temperatures and corrosive conditions associated with combustion gases.

[0060] 6. Sustainability: By eliminating the need for external vapor treatment units and reducing energy requirements compared to conventional high- temperature thermal oxidation, the catalytic oxidizers enhance the overall environmental sustainability of the system. Their ability to operate at lower temperatures further reduces energy consumption, improving operational efficiency and lowering the carbon footprint.

[0061] In a preferred embodiment, said catalysts can be placed before the reburn pipe (16) as well or instead of on the gasses from the heat exchange volumes (33).

[0062] Combustion Chamber Design and Adaptability The combustion chamber (9) is a central component of the containerized thermal treatment system, engineered to achieve oxidizing conditions exceeding l,400°C with a residence time of at least one second. These parameters are advantageous for ensuring near-complete destruction of organic pollutants, including thermally stable compounds like PFAS. Its design incorporates several innovative features:

[0063] 1. Burner Integration: The chamber is equipped with a combustion head (41), which operates in conjunction with the fuel injector (20) to deliver a consistent flame. This flame intensity and position can be dynamically adjusted within the combustion chamber (9) to concentrate heat in the most areas areas of the container.

[0064] 2. Airflow Optimization: The system includes a fan extractor (22) and an air intake valve (12), which together regulate the airflow and maintain an oxygen-rich environment. This ensures efficient combustion and prevents incomplete oxidation of contaminants.

[0065] 3. Thermal Insulation and Durability: The chamber is lined with refractory cement (13) to retain heat, stabilize high-temperature conditions, and protect the structural integrity of the system. This insulation reduces energy losses and enhances operational efficiency.

[0066] 4. Energy Recovery: The front panel (40) incorporates heat exchangers that recover energy from the exhaust gases and preheat the primary combustion air entering the chamber. This design reduces fuel consumption while maintaining the high temperatures required for complete pollutant destruction.

[0067] 5. Reburn Integration: The system features a reburn flexible line (16) that routes partially combusted vapors back into the combustion chamber for secondary treatment. This process ensures the breakdown of residual contaminants while maximizing the efficiency of the heat generated.

[0068] These features work synergistically to achieve optimal combustion conditions, ensuring that all organic pollutants are destroyed effectively while minimizing secondary emissions. The modular and adaptable design of the combustion chamber enables precise energy delivery, improving the overall efficiency and sustainability of the remediation process.

[0069] Heat Transfer Efficiency The heat transfer system in the containerized thermal treatment system is meticulously designed to maximize the utilization of thermal energy generated by the combustion chamber (9). It ensures efficient and uniform heating of the heating elements (10), while minimizing energy losses and operational costs. This is achieved through several integrated features, as illustrated in the figures:

[0070] 1. Circulation of Hot Combustion Gases: The heat exchange volumes, including panels in the front area (24) and top insulated panel (5) are specifically engineered to circulate the hot combustion gases generated within the system after they have already passed through the main heating panels. These gases transfer heat directly to the contaminated soil (1) by flowing through the combustion chamber (9) and the surrounding space between heating panels (33), ensuring consistent and uniform heating throughout the soil matrix.

[0071] 2. Heat Exchangers for Energy Recovery: Embedded in the front area (40) are highly efficient heat exchangers (39), which recover thermal energy from the exiting combustion gases. This energy is used to preheat the primary combustion air entering through the air intake valve (12), significantly reducing the fuel required to maintain high temperatures in the combustion chamber.

[0072] 3. Thermal Insulation: To prevent heat loss, the entire system, including the combustion chamber (9) is lined with refractory cement (13). This ensures that the maximum amount of generated heat is directed towards high temperature and high destruction rate before being passed on to the materials in the container.

[0073] 4. Gas Flow Path Control: The system includes configurable plumbing in the front area (40), enabling operators to control the flow path of hot combustion gases and vapors. This design allows for two operational modes: o Reburn Mode: Vapors can be directed back into the combustion chamber via the reburn flexible line (16) for further treatment. o Bypass Mode: Vapors can be diverted directly to an external vapor treatment unit (VTU) when needed, providing operational flexibility. In said preferred embodiment, the reburn pipe (16) is not connected to the primary air input (12) but directly to an external separate Vapor Treatment Unit.

[0074] 5. Enhanced Insulation via Welded Roof Panel: The roof panel (5) is welded except for the last section (6), which can be lifted for loading purposes. This fixed structure minimizes thermal losses while maintaining accessibility for material handling.

[0075] 6. Direct Energy Transfer to Soil: The combustion chamber (9) is designed for maximum thermal conductivity, ensuring that the heat generated by the burners and circulated gases is efficiently transferred to the soil matrix. This eliminates the need for additional heating elements, simplifying the system while improving heat delivery.

[0076] These heat transfer features ensure that the energy generated is utilized efficiently, not only for destroying contaminants but also for heating the soil uniformly. This minimizes energy consumption, accelerates treatment times, and reduces operational costs, making the system both effective and sustainable.

[0077] Vapor Handling and Reburn Bypass

[0078] The vapor handling system in the containerized thermal treatment system is designed for flexibility, efficiency, and environmental compliance. It ensures that vaporized contaminants generated during the thermal treatment process are managed effectively, either through additional combustion or external treatment. Key features and their integration, as referenced in the figures, include:

[0079] 1. Reburn Integration: The system incorporates a reburn flexible line (16) that allows vaporized contaminants to be reintroduced into the combustion chamber (9) for secondary combustion. This ensures that residual contaminants undergo complete oxidation, achieving near-total destruction of organic pollutants.

[0080] 2. Bypass Option: Plumbing in the front area (40) is configured to enable a bypass option. When activated, vaporized contaminants are routed directly to an external vapor treatment unit (VTU) for additional processing. This flexibility allows the system to adapt to site-specific requirements or regulatory constraints.

[0081] 3. Compressor for Cleaning: A compressor located at the front of the container facilitates automated cleaning of the vapor handling system between treatment batches. This feature ensures that the system remains free of clogs and maintains optimal performance over extended periods of operation.

[0082] 4. Catalytic Oxidizer for Polishing: At the exit of the combustion gases (11), a catalytic oxidizer serves as a final polishing step, ensuring that any residual contaminants or degradation byproducts are fully converted into harmless compounds such as CO2 and H2O. The catalytic oxidizer also acts as a passive backup system, continuing to provide emission control during short-term burner shutdowns.

[0083] 5. Vacuum Application Capability: The system is capable of applying a controlled vacuum within the treatment area, with operating pressures ranging from 100-500 mbar (preferably 200-350 mbar, and ideally 250- 300 mbar). This vacuum reduces the boiling point of contaminants, allowing for their vaporization at lower temperatures. This not only protects materials such as steel from excessive heat but also improves energy efficiency.

[0084] 6. Minimized Air Ingress: The container's design, including the welded roof panel and insulated top panel (5), prevents the ingress of cold outside air during vacuum operation. This ensures stable thermal conditions within the system, maintaining efficient contaminant volatilization without energy loss.

[0085] 7. Vapor Collection System: Vaporized contaminants are directed to the vapor extraction tube (35), which ensures controlled and efficient removal of gaseous byproducts from the soil. This tube is strategically integrated with the heat exchange volume (33) and protected by surrounding thermal insulation (14) to maintain vapor temperature and flow.

[0086] 8. Liquid Management: The vapor collection system is positioned so that there are no liquids in the system and that all vapors pass through the combustion chamber (9). However, should liquids be present at the bottom of the container they are collected via the slots for liquid collection (7), and are separated before they can be vaporized unnecessarily. This reduces the burden on the vapor handling system, conserves energy, and accelerates the treatment process.

[0087] These features collectively provide a robust vapor handling system that not only maximizes the efficiency of contaminant destruction but also ensures compliance with stringent environmental standards. The flexibility to alternate between reburn mode and bypass mode, coupled with the polishing capabilities of the catalytic oxidizer, makes the system adaptable, reliable, and environmentally sustainable.

[0088] Automatic Cleaning and Liquid Collection

[0089] The cleaning system in the containerized thermal treatment setup is a key innovation designed to maintain operational efficiency, reduce downtime, and ensure consistent performance over prolonged usage. Its integration with other system components enhances automation and minimizes manual intervention. Key features, as referenced in the figures, include:

[0090] 1. Compressor for Automatic Cleaning: A compressor (38) located in the front area (40) facilitates automated cleaning processes between treatment batches. This system generates high-pressure air to dislodge residues and particulates from critical components, such as the heat exchange volume (33), vapor extraction tube (35), heat exchangers (39) and combustion chamber (9), ensuring unrestricted airflow and consistent combustion efficiency.

[0091] 2. Cleaning of Vapor Handling System: The vapor extraction tube (35) and associated plumbing benefit from the compressor-assisted cleaning, which removes residual contaminants or condensation that could accumulate during operation. This feature ensures that vapor flow remains unimpeded, maintaining the system's efficiency and reliability.

[0092] 3. Automated Cycle Integration: The cleaning system is integrated into the operational cycles of the container. Between treatment batches, cleaning can be initiated automatically without requiring manual access, reducing downtime and labor costs while ensuring that the system is ready for the next operation.

[0093] 4. Preservation of Heat Transfer Efficiency: Residue build-up on the heating elements (10) or thermal insulation (14) can reduce heat transfer efficiency over time. The automated cleaning system mitigates this risk by periodically clearing these surfaces, preserving optimal thermal performance.

[0094] 5. Liquid Recovery Support: The slots for liquid collection (7) and the bottom plate are also cleaned using the compressor system to ensure that accumulated liquids or debris are removed. This prevents blockages and enhances the efficiency of the liquid recovery system, accelerating the treatment process.

[0095] 6. Ease of Maintenance: By automating the cleaning process, the system minimizes the need for manual intervention in hard-to-reach areas, such as the reburn flexible line (16) or the internal sections of the combustion chamber (9). This reduces the risk of operational errors and prolongs the lifespan of critical components.

[0096] 7. Design for Minimal Downtime: The compressor's placement at the front of the container ensures accessibility and ease of servicing, allowing maintenance teams to quickly address any issues without disrupting the overall operation of the system.

[0097] 8. Environmental Considerations: The cleaning process is designed to capture dislodged particulates and contaminants, preventing them from being released into the environment. This aligns with the system's broader sustainability goals and compliance with environmental regulations.

[0098] The cleaning system, with its compressor-driven automation and integration with operational cycles, significantly improves the system's uptime and reliability. By maintaining the cleanliness and efficiency of key components, it reduces treatment costs, enhances performance, and ensures uninterrupted operation for extended periods.

[0099] Material Handling Innovations

[0100] The material handling system in the containerized thermal treatment solution is designed to maximize operational efficiency, streamline loading and unloading processes, and minimize downtime. By eliminating traditional complexities, it introduces a highly efficient and user-friendly method for managing contaminated soil during treatment. Key features, as referenced in the figures, include:

[0101] 1. Elimination of Heating Tubes: Unlike conventional systems that rely on internal heating tubes, this design removes the need for such components. This innovation simplifies the loading and unloading of soil within the container, significantly reducing preparation time and operational complexity.

[0102] 2. Top Loading with Liftable Roof Panel: The roof panel is welded for optimal insulation but includes a liftable section at the last 2 meters. This section allows for soil to be loaded from above, rather than through side or end openings. This configuration not only simplifies loading but also enhances the insulation of the container during operation by minimizing moving parts.

[0103] 3. Expandable Container Design: The system can be extended by attaching a second container to the base container. This second container lacks the technical equipment housed in the front area (40), allowing for a significant increase in soil treatment capacity— more than doubling the volume— with minimal additional cost. This modular setup improves scalability for larger remediation projects.

[0104] 4. Quick Turnaround Times: The removal of internal heating tubes and the streamlined design of the container enable rapid soil unloading after treatment. Treated soil can be easily removed via the doors at the back of the container (26), and the container is ready for reloading almost immediately. This reduces downtime between batches and increases the overall throughput of the system.

[0105] 5. Integrated Liquid Collection: The slots for liquid collection (7) in the bottom plate allow for the separation and recovery of free liquids during treatment. By isolating liquids from the soil before heating, the system reduces unnecessary vaporization, accelerates treatment, and conserves energy. This feature also simplifies cleanup after treatment, further enhancing material handling efficiency.

[0106] 6. Improved Uptime and Cost Efficiency: By optimizing the loading, unloading, and cleaning processes, the system maximizes equipment uptime, reducing the overall cost of treatment. Operators can handle larger volumes of soil with fewer delays, making the process more economical and scalable.

[0107] 7. Closed-System Design for Vacuum Application: The welded roof panel and insulated structure allow the container to operate as a nearly sealed system. This enables the application of controlled vacuum conditions (100- 500 mbar, preferably 250-300 mbar) without drawing in outside air, which could complicate material handling and disrupt thermal profiles.

[0108] 8. Compatibility with Multiple Soil Types: The absence of rigid internal components allows the system to handle a wide range of soil compositions and contaminant levels, enhancing its versatility across different project requirements. It is highly suitable for sludges and high moisture solids.

[0109] The advanced material handling system is a significant improvement over traditional methods, offering faster, simpler, and more cost-effective operations. By focusing on ease of loading and unloading, modular scalability, and integration with other system features, it ensures high throughput and reduced downtime, making it an advantageous component of the overall thermal treatment process.

[0110] Roof Panel and Loading Efficiency

[0111] The roof panel in the containerized thermal treatment system is an advantageous design element that enhances both thermal insulation and operational efficiency. The panel is predominantly welded, except for the final section, which can be lifted to facilitate loading. This configuration, as detailed in the figures, offers several key benefits: 1. Maximized Insulation: The welded portion of the roof panel ensures exceptional thermal insulation, significantly reducing heat loss during operation. This design minimizes energy consumption by concentrating thermal energy within the container, allowing for more efficient soil heating and contaminant treatment.

[0112] 2. Liftable Loading Section: The final section of the roof is designed to be lifted, creating a convenient loading opening. This feature allows contaminated soil to be loaded directly from above, bypassing the need for operators to manoeuvre within the container. This simplifies the loading process and reduces the time required to prepare the container for treatment.

[0113] 3. Energy Efficiency: By combining a welded design for most of the roof with a liftable section only where necessary, the system maintains a high level of insulation without compromising functionality. The reduced thermal losses translate to lower energy requirements, improving the cost-effectiveness of the treatment process.

[0114] 4. Seamless Integration with Material Handling: The liftable roof section aligns with the material handling system, enabling quick and easy soil loading while maintaining the container's overall structural integrity. This configuration supports the streamlined loading and unloading processes, maximizing equipment uptime.

[0115] 5. Enhanced Durability: The welded design of the majority of the roof ensures structural durability and resistance to wear over extended operations. The movable section is constructed with robust materials to withstand repeated use without compromising the container's overall performance.

[0116] 6. Vacuum Compatibility: The welded design complements the system's ability to operate under controlled vacuum conditions (100-500 mbar, preferably 250-300 mbar), ensuring that the treatment area remains sealed and insulated during the process. This prevents the ingress of cold air, which could disrupt thermal efficiency and pressure stability.

[0117] 7. Operational Flexibility: The liftable roof panel allows operators to adapt the system to various project requirements, including different soil volumes and loading equipment. The design supports efficient operation in a wide range of site conditions.

[0118] By combining high thermal efficiency, ease of use, and structural durability, the roof panel design contributes significantly to the system's overall performance. It streamlines the loading process while maintaining optimal energy efficiency, making it a vital component of the containerized thermal treatment solution. Vacuum Application and Pressure Control

[0119] The vacuum application and pressure control system in the containerized thermal treatment system enhances operational efficiency and energy conservation by optimizing the conditions for contaminant vaporization. This feature is seamlessly integrated into the system's design and provides several key benefits:

[0120] 1. Lower Vaporization Temperatures: By reducing the internal pressure to 100-500 mbar (preferably 250-300 mbar), the system lowers the boiling points of contaminants. This allows volatile and semi-volatile compounds to vaporize at reduced temperatures, protecting the structural integrity of components like heat exchanger volumes (33) and heater elements (10) and minimizing energy consumption.

[0121] 2. Closed-System Design: The welded roof panel and insulated top panel (5) create a nearly airtight structure, preventing the ingress of cold outside air. This ensures stable thermal conditions, maintaining the efficiency of the vacuum and avoiding temperature disruptions.

[0122] 3. Enhanced Energy Efficiency: Lower operational temperatures under vacuum conditions reduce the thermal load on the combustion chamber (9), extending the lifespan of critical components and lowering fuel costs.

[0123] 4. Improved Contaminant Mobilization: Applying a vacuum facilitates the efficient extraction of contaminants via the vapor extraction tube (35), accelerating treatment cycles while ensuring thorough remediation.

[0124] 5. Integrated Control: The system's vacuum capabilities are precisely managed through integrated sensors and controls, ensuring consistent performance tailored to the specific requirements of the soil being treated.

[0125] By reducing the pressure and maintaining a sealed environment, the vacuum application and pressure control system enhances both the performance and sustainability of the thermal treatment process, providing superior contaminant removal with reduced operational costs.

[0126] Environmental and Economic Benefits

[0127] This invention offers significant environmental and economic advantages:

[0128] 1. Energy Efficiency: Integrated heat recovery systems and improved insulation minimize fuel consumption and operational costs. 2. Sustainability: The elimination of secondary waste streams and the use of catalytic polishing reduce the overall environmental impact.

[0129] 3. Scalability and Flexibility: Modular extensions and dual-path vapor management adapt the system to a wide range of project sizes and site conditions.

[0130] In a preferred embodiment, the containerized thermal remediation system further comprises a secondary vapor treatment unit positioned downstream of the integrated combustion chamber. This vapor treatment unit includes at least one granular activated carbon (GAC) filter, preferably at least two granular activated carbon (GAC) filters arranged in series, configured to capture any residual contaminants or byproducts that may pass unoxidized through the primary combustion system. The GAC filters are dimensioned to provide a vapor residence time of at least three seconds, ensuring high capture efficiency. This configuration allows for continued environmental compliance in the event of incomplete oxidation of contaminants, particularly during startup, shutdown, maintenance, or system perturbations.

[0131] In a further embodiment, the system includes a real-time gas analysis module configured to monitor the concentration of hydrogen fluoride (HF) in the exhaust gases. Preferably, a photoacoustic gas analyzer, such as a Gasera HF One or equivalent device, is employed, capable of detecting HF concentrations below 0.5 parts per billion (ppb). This monitoring system enables continuous verification that fluorinated contaminants, particularly PFAS-derived compounds, are being fully mineralized into benign products during the oxidation process. The HF detection system may be connected to the system's control unit for real-time alerts in case of abnormal fluorine emissions.

[0132] In yet another preferred embodiment, the containerized system is equipped with an auxiliary emergency power supply, such as a generator, configured to maintain operation of the vapor extraction fans and safety-critical components during power failures. The emergency system ensures that the container remains under controlled sub-atmospheric pressure at all times, preventing the uncontrolled release of vapors and preserving the integrity of the thermal treatment cycle. The emergency generator is automatically activated upon loss of external electrical power and supplies sufficient energy to operate advantageous ventilation and monitoring equipment for a period exceeding 12 hours. In a further aspect, the thermal design of the system has been validated through numerical simulation, using computational fluid dynamics modeling software such as ANSYS Fluent. Simulations demonstrate that the system is capable of achieving uniform heating of contaminated soil volumes up to 15 cubic meters, reaching center temperatures of at least 320 °C within 20 operational days, even in soils containing up to 20% water by weight. Furthermore, simulations confirm that combustion gases remain within the internal heating tubes for a residence time exceeding 1.5 seconds at temperatures above 1400 °C, ensuring efficient thermal oxidation of vaporized contaminants. These simulation results corroborate the efficacy of the system's integrated heating and destruction architecture.

[0133] In a further or another embodiment, the system is configured to operate in batch processing cycles. A first batch of contaminated material may be treated under standard parameters, while subsequent batches are adapted based on real-time analysis of the treatment effectiveness, soil characteristics, and vapor-phase emissions. Adjustments may include variations in heating time, burner energy input, soil moisture conditioning, or the introduction of supplemental contaminant loads to optimize system performance and resource utilization.

[0134] Advanced Automation and Process Control

[0135] According to a further or another embodiment, the containerized thermal treatment system incorporates comprehensive automation features that transform it into a fully autonomous soil remediation unit. The autonomous soil remediation unit may thus integrate one or more sensors, preferably strategically positioned throughout the container, chosen from the group of temperature sensors, pressure sensors, oxygen sensors, gas analyzers, or combinations thereof. These sensors may continuously transmit real-time data to an advanced control system that dynamically adjusts operational parameters without human intervention. Said temperature sensors are preferably positioned at multiple depths within the soil matrix. Said pressure sensors are preferably positioned in the vapor handling system. Said oxygen sensors are preferably position in the combustion chamber. Said gas analyzers are preferably positioned in the exhaust stream.

[0136] The autonomous soil remediation unit may utilize adaptive algorithms to optimize the power input based on the real-time heating profile of the soil, automatically modulating burner output to maintain ideal heating rates and target temperatures while minimizing energy consumption. The autonomous soil remediation unit may continuously monitor residence times within the inner pipe, adjusting gas flow rates and combustion parameters to ensure complete destruction of contaminants under varying soil conditions and moisture content.

[0137] According to a further or another embodiment, the autonomous soil remediation unit may comprise a user interface that provides visual feedback on treatment progress, system status, and / or estimated completion time. When the soil reaches the target treatment parameters and contaminant levels are verified to be below threshold values, the system may automatically alert operators with visual and / or audible signals indicating that the remediation cycle is complete and the soil is ready for replacement. This notification may appear on a screen, for example a high-resolution touchscreen display, that may also provide detailed treatment logs, energy consumption metrics, and destruction efficiency data for regulatory documentation.

[0138] According to a further or another embodiment, the autonomous soil remediation unit may incorporate predictive maintenance algorithms that monitor component performance and alert operators to potential issues before they impact operation. As such, system uptime and treatment efficiency may be further improved.

[0139] The several embodiments as described herein may significantly reduce labor requirements, eliminate human error, standardize treatment outcomes, and enable 24 / 7 operation with minimal supervision, substantially improving both the economics and reliability of the remediation process.

[0140] In a specific embodiment, the invention provides a containerized method for the thermal treatment of contaminated solids and pasteous materials and waste, comprising:

[0141] • at least one thermally insulated container, designed with structure for minimizing heat loss, configured for soil loading from one side or from a top liftable panel and providing heating of the materials;

[0142] • at least one heat production unit comprising: o a burner control box for regulating the combustion process, o a combustion chamber capable of reaching oxidizing conditions for total destruction of said contaminants, o a combustion head, positioned within the combustion chamber and adaptable to varying depths to target thermal energy based on soil conditions, said combustion chamber located between thermally conductive heating panels that ensure efficient energy transfer to the contaminated materials; • at least one burner capable of simultaneous heating of contaminated materials and vapor-phase contaminant destruction through primary and reburn mechanisms;

[0143] • an autonomous ventilation system for controlled circulation of combustion gases between the inner heating tubes and heating panels, ensuring uniform thermal distribution;

[0144] • flexible gas and / or liquid fuel lines and steel extension tubes, connected to the combustion head and preheated to optimize fuel efficiency, configured for the continuous supply of gaseous or liquid fuel;

[0145] • a monitoring and control system incorporating sensors for real-time adjustment and regulation of temperature, pressure, combustion parameters, and destruction efficiency to ensure optimal operational performance.

[0146] In a further embodiment, the burners operate at temperatures exceeding l,400°C and provide a residence time of at least 1 second to ensure near-complete destruction of contaminants. In another further embodiment, wherein the burners operate at temperatures exceeding l,200°C and provide a residence time of at least 2 seconds to ensure near-complete destruction of contaminants.

[0147] In a further or another embodiment, the contaminants treated include volatile and semi-volatile organic compounds such as PFAS, dioxins, pesticides, PCBs, or chlorinated solvents.

[0148] In a further or another embodiment, the containerized design allows for portability and modular deployment, facilitating on-site remediation at remote locations.

[0149] In a further or another embodiment, the contaminants can be directed to undergo an additional catalytic oxidation step.

[0150] In a further or another embodiment, an automatic compressed air system allows for cleaning up the container and all its piping after having been emptied.

[0151] In a further or another embodiment, combustion gasses are directed to a separate air treatment unit, separate from the containers.

[0152] In a further or another embodiment, an oxygen concentrator is integrated into the system to supply enriched oxygen to the burners. In a specific embodiment, the invention provides a containerized device for the thermal treatment of contaminated solids and pasteous materials and waste, comprising:

[0153] • at least one thermally insulated container, designed with structure for minimizing heat loss, configured for soil loading from one side or from a top liftable panel and providing heating of the materials;

[0154] • at least one heat production unit comprising: o a burner control box for regulating the combustion process, o a combustion chamber capable of reaching oxidizing conditions for total destruction of said contaminants, o a combustion head, positioned within the combustion chamber and adaptable to varying depths to target thermal energy based on soil conditions, said combustion chamber located between thermally conductive heating panels that ensure efficient energy transfer to the contaminated materials;

[0155] • at least one burner capable of simultaneous heating of contaminated materials and vapor-phase contaminant destruction through primary and reburn mechanisms;

[0156] • an autonomous ventilation system for controlled circulation of combustion gases between the inner heating tubes and heating panels, ensuring uniform thermal distribution;

[0157] • flexible gas and / or liquid fuel lines and steel extension tubes, connected to the combustion head and preheated to optimize fuel efficiency, configured for the continuous supply of gaseous or liquid fuel;

[0158] • a monitoring and control system incorporating sensors for real-time adjustment and regulation of temperature, pressure, combustion parameters, and destruction efficiency to ensure optimal operational performance.

[0159] In a further embodiment, the burners operate at temperatures exceeding l,400°C and provide a residence time of at least 1 second to ensure near-complete destruction of contaminants. In a further embodiment, the burners operate at temperatures exceeding l,200°C and provide a residence time of at least 2 seconds to ensure near-complete destruction of contaminants. In a further or another embodiment, the contaminants treated include volatile and semi-volatile organic compounds such as PFAS, dioxins, PCBs, and chlorinated solvents.

[0160] In a further or another embodiment, the containerized design allows for portability and modular deployment, facilitating on-site remediation at remote locations.

[0161] In a further or another embodiment, the contaminants can be directed to undergo a catalytic oxidation step.

[0162] In a further or another embodiment, an automatic compressed air system allows for cleaning up the container after having been emptied

[0163] In a further or another embodiment, combustion gasses are directed to a separate air treatment unit, separate from the containers.

[0164] In specific aspect, the invention provides a heat production unit for use in a thermal remediation system for treating contaminated solids or waste, comprising

[0165] • a combustion head

[0166] • a combustion chamber and

[0167] • a reburn inlet.

[0168] In a specific embodiment the heat production unit comprises:

[0169] • a combustion head configured to mix a primary fuel with an oxidizer to produce a primary flame,

[0170] • a combustion chamber extending from the combustion head and positioned such that a substantial portion of the flame is located within or adjacent to the contaminated solids or waste, and

[0171] • a reburn inlet arranged to introduce vaporized contaminants into the flame tube.

[0172] This arrangement enables direct in-situ heating and oxidation of contaminants, minimizing heat losses and promoting effective thermal destruction. The advantage is that heat losses are minimized and thermal efficiency for contaminant destruction is maximized.

[0173] In a further embodiment, the integrated combustion chamber operates at a temperature between 1400°C and 1600°C and provides a residence time of at least one second for vaporized contaminants. This allows a near-complete thermal destruction of persistent organic contaminants such as PFAS.

[0174] In another further embodiment, the integrated combustion chamber operates at a temperature between 1200 and 1400°C and provides a residence time of at least two seconds for vaporized contaminants. In another or further embodiment, the combustion chamber is elongated to maintain vaporized contaminants for a residence time of at least one to two seconds at temperatures exceeding 1400°C.

[0175] In another or further embodiment, the reburn inlet is configured to introduce vaporized contaminants tangentially into the combustion chamber. This enhances turbulence inside the combustion chamber, promoting better mixing and more complete oxidation of contaminants.

[0176] In another or further embodiment, the combustion chamber is lined with a refractory material preferably capable of withstanding internal temperatures up to l,800°C. In this way, the chamber maintains high thermal stability and durability even under continuous high-temperature operation.

[0177] In another or further embodiment, the combustion head comprises a fuel nozzle, an oxidizer inlet, and an igniter.

[0178] In another or further embodiment, the combustion head is mounted in an adjustable manner within the combustion chamber, allowing the position of the flame to be varied. The advantage is that heat delivery can be focused towards zones with the highest contaminant loads, improving treatment efficiency.

[0179] In another or further embodiment, the oxidizer is provided by an oxygen-enriched gas stream supplied from an oxygen concentrator or a liquid oxygen source, with an oxygen concentration in the range of 30% to 100%. The combustion temperature and oxidation efficiency are increased, ensuring better destruction rates of persistent contaminants.

[0180] In another or further embodiment, the combustion chamber comprises turbulenceinducing elements, preferably swirl baffles or vanes. The advantage is that vaporized contaminants and combustion gases are thoroughly mixed, maximizing the chemical breakdown of pollutants. In another or further embodiment, a control system is provided that monitors the flame temperature, oxygen concentration, and vapor flow, and dynamically adjusts fuel and oxidizer input to maintain a flame temperature between l,400°C and l,600°C. Stable high-efficiency combustion is maintained even when the contaminant load fluctuates.

[0181] In another or further embodiment, the burner further includes integrated sensors for real-time measurement of combustion parameters including temperature, pressure, and gas composition to achieve precise operational control, improving safety and efficiency.

[0182] In another or further embodiment, the vaporized contaminants are extracted from the contaminated material by a vapor collection system and introduced into the combustion chamber via the reburn inlet. This makes sure volatilized contaminants are destroyed immediately, minimizing emissions and waste.

[0183] In another or further embodiment, the heat production unit is capable of simultaneously heating the contaminated material and oxidizing vaporized contaminants within the same structure. This is advantageous because soil treatment and vapor treatment are combined, improving overall energy efficiency.

[0184] In another or further embodiment, the combustion head is adapted to use fuels selected from diesel, biodiesel, natural gas, biogas, or combinations thereof. Fuel flexibility is achieved, allowing use of the most economical or available energy source at the site.

[0185] In another or further embodiment, a containerized device is provided comprising at least one thermally insulated container and at least one heat production unit as described above, arranged to place the combustion chamber in thermal contact with the contaminated solids or waste.

[0186] In another or further embodiment, the container is an ISO shipping container. By preference, the container is a modified ISO shipping container. The container can as such be transported globally using existing logistic networks without special adaptations. By more preference, said ISO shipping container has dimensions corresponding to a standard 20-foot or 40-foot shipping container. By most preference, said container is a modified 20-foot shipping container. In another or further embodiment, the containerized system further comprises an automated cleaning subsystem to clean the vapor handling system between treatment batches. In this way operational downtime and manual maintenance may be minimized.

[0187] In another or further embodiment, the containerized system is modular and designed for scalability by operating multiple units concurrently.

[0188] In another or further embodiment, a vacuum pump is integrated into the containerized system to maintain internal pressures between 100 mbar and 500 mbar. This ensures that contaminants may be volatilized at lower temperatures, reducing thermal stress and energy consumption.

[0189] In another or further embodiment, the roof and side panels of the container are welded and insulated to minimize external air ingress during vacuum operation ensuring that thermal stability is improved during treatment cycles.

[0190] In another or further embodiment, hot combustion gases are circulated through heat exchange volumes around the contaminated material after primary heating. Energy recovery is maximized, improving the overall thermal efficiency of the system.

[0191] In another or further embodiment, heat exchangers are embedded within the front panel of the container to recover waste heat from the exhaust gases and preheat incoming combustion air. The advantage is that the system consumes less fuel and operates more sustainably.

[0192] In another or further embodiment, the vapor handling system includes configurable plumbing allowing operators to switch between reburn mode and bypass mode to an external vapor treatment unit. The advantage is that operational flexibility is maintained to meet site-specific environmental requirements.

[0193] In another or further embodiment, a catalytic oxidizer is positioned downstream of the combustion system to polish residual gases. The effect is that final emissions are extremely low in volatile organic compounds and acid gases, improving compliance with stringent air quality standards.

[0194] In another or further embodiment, the system comprises a compressor that automatically cleans vapor lines and handling components between treatment batches. The advantage is that clogging is prevented and system reliability is increased.

[0195] In another or further embodiment, vaporized contaminants are extracted via insulated vapor tubes protected by surrounding thermal insulation. The effect is that vapor temperatures are maintained and condensation losses are minimized.

[0196] In another or further embodiment, free liquids collected from the contaminated material are separated through slots before vaporization. The advantage is that unnecessary evaporation energy is avoided, accelerating treatment cycles and reducing fuel use.

[0197] In another or further embodiment, the combustion chamber and associated heat transfer elements are designed to transfer heat conductively into the contaminated matrix without the need for additional separate heating systems. The effect is that the system remains compact, simple, and highly energy efficient.

[0198] The burner is preferably configured in a remote flame arrangement, wherein the combustion chamber and the flame itself are positioned inside the heating tube, embedded directly within the soil matrix. The term remote flame as used herein refers to a configuration in which the flame is generated at a distance from the burner head and propagated through a confined combustion zone into the treatment volume. This ensures that the generated thermal energy is delivered directly into the soil, without losses to the surrounding structure. The effect is a substantial improvement in heat transfer efficiency and a reduction in fuel consumption.

[0199] The burner can be adapted to receive and destroy vaporized contaminants that are extracted from the soil during heating. These vapors are introduced directly into the flame zone, where they are exposed to oxidizing conditions. The effect is that thermally mobilized compounds such as PFAS are oxidized immediately upon volatilization, avoiding the need for separate treatment units and reducing the risk of generating persistent by-products.

[0200] The combustion chamber can be designed to provide temperatures exceeding l,400°C and a gas residence time of at least 1 second under turbulent flow conditions. This ensures complete thermal oxidation of stable organic molecules such as perfluoroalkyl compounds. According to the inventor's findings and combustion modeling, such parameters are sufficient to achieve destruction efficiencies greater than 99.999%.

[0201] The geometry of the burner and heating tube can be configured to promote turbulence in the flame region. This is achieved by introducing the vaporized contaminants tangentially into the combustion chamber or by integrating turbulence-inducing inserts such as swirl baffles. The advantage is that improved mixing of oxygen and contaminants is achieved, resulting in more efficient oxidation and reduced variability in emissions.

[0202] To monitor and ensure complete destruction of contaminants, a hydrogen fluoride detector can be placed downstream of the burner. The presence of HF in the flue gas is considered a reliable indicator of PFAS mineralization. By correlating HF levels with fuel and vapor input, a fluorine mass balance can be estimated to support regulatory compliance.

[0203] The burner can be operated using propane gas or other suitable fuels such as natural gas or diesel. In a preferred embodiment, propane is used to generate a high- temperature flame with consistent combustion properties. The fuel supply can be coupled with a sensor system that monitors tank levels and sends refill notifications automatically. This ensures uninterrupted operation and stable thermal output.

[0204] A control system may be integrated with the burner to regulate combustion parameters in real time. Such parameters include flame temperature, air-to-fuel ratio, and oxygen concentration. Sensors can be used to provide continuous data to the control system, which adjusts inputs dynamically. The effect is consistent operation even under variable soil and vapor conditions.

[0205] The combustion system can optionally include a backup catalytic oxidation stage for treating residual carbon monoxide or unreacted hydrocarbons at the outlet of the heating pipe. This system, operating at 350-500°C, ensures that any incomplete combustion is corrected before emission, adding a safety layer in case of high contaminant load.

[0206] The several embodiments as described herein provide a significant advantage by enabling a two-stage combustion process that enhances both treatment efficiency and environmental sustainability. The burner arrangement, comprising a combustion head that produces a primary flame within or adjacent to the contaminated solids and a reburn inlet that introduces vaporized contaminants into the flame tube, facilitates simultaneous soil heating and contaminant destruction in a single unified system. This configuration ensures that thermally mobilized compounds such as PFAS are exposed to oxidizing conditions, resulting in near-complete thermal oxidation without requiring separate vapor treatment units.

[0207] The integration of primary combustion with an in-situ reburn system substantially improves the overall thermal efficiency of the remediation process while reducing operational complexity and waste generation. By positioning the combustion chamber and flame directly within the soil matrix in a remote flame arrangement, thermal energy is delivered efficiently to the contaminated materials, minimizing heat losses to surrounding structures. Furthermore, the arrangement allows vaporized contaminants to be oxidized immediately upon volatilization, thereby converting persistent organic pollutants into benign byproducts and / or harmless compounds without generating secondary waste streams that would require additional treatment or disposal.

[0208] The present invention, while primarily described with reference to the remediation of soil contaminated with per- and polyfluoroalkyl substances (PFAS), is not limited to this application. The method and system disclosed herein are equally applicable to the treatment of a wide range of contaminated solids, including but not limited to activated carbon, ion-exchange resins, sludges, filter materials, and other solid matrices bearing persistent organic pollutants. This versatility allows the system to treat diverse waste streams containing contaminants such as PFAS, polychlorinated biphenyls (PCBs), dioxins, pesticides, solvents, hydrocarbons, and explosives.

[0209] The invention may be particularly advantageous in integrated treatment trains for complex environmental remediation projects. In such treatment trains, PFAS- contaminated soil, which constitutes the primary pollution source, can be excavated and treated directly in the containerized thermal remediation units described herein. Simultaneously, associated PFAS-contaminated groundwater can be subjected to complementary treatments, such as adsorption onto activated carbon, foam fractionation, or ion-exchange resin techniques. Concentrated PFAS waste streams resulting from groundwater treatment can be treated directly in the containerized system if appropriate, or alternatively, combined with soil or other solids to be thermally treated to ensure full destruction of PFAS compounds. The flexibility of the containerized system to accept mixtures of soil, adsorbents, sludges, and concentrates allows for complete management of both solid and concentrated liquid waste phases within the same technological framework. This significantly simplifies logistics, reduces the need for separate destruction facilities, and enhances overall treatment efficiency.

[0210] Moreover, because the system is modular, scalable, and capable of rapid onsite deployment, it is particularly well-suited for staged remediation projects, where diverse contamination sources must be addressed concurrently or sequentially. The ability to flexibly adjust to the treatment of various solids contaminated with different classes of organic pollutants provides a substantial operational advantage in meeting stringent environmental regulations and sustainability goals.

[0211] DESCRIPTION OF FIGURES

[0212] The following description of the figures of specific embodiments of the invention is merely exemplary in nature and is not intended to limit the present teachings, their application or uses. Throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.

[0213] 1 Contaminated Material

[0214] 2 Right Insulation Panel

[0215] 3 Left Insulation Panel

[0216] 4 Insulated Doors

[0217] 5 Insulated Top Panel

[0218] 6 Insulated Opening Panel

[0219] 7 Slots for Liquid Collection

[0220] 8 Slots for Vapor Collection

[0221] 9 Combustion Chamber

[0222] 10 Heating Elements (Plates)

[0223] 11 Exit of Combustion Gases

[0224] 12 Input of Primary Air and Reburn Vapors

[0225] 13 Refractory Cement

[0226] 14 Thermal Insulation

[0227] 15 Threads for Internal Heating Tube

[0228] 16 Reburn pipe 17 Sleeve for Assembling Heating Tubes

[0229] 18 Fixed-Length Elements of the Internal Tube

[0230] 19 Metal Coil for Liquid Fuel Preheating

[0231] 20 Fuel Injector

[0232] 21 Outlet of Heating Tube

[0233] 22 Fan Extractor

[0234] 23 Container frame structure

[0235] 24 Heat exchange volume within the front Panel of Container

[0236] 25 Container Extension

[0237] 26 Doors at Back of Container

[0238] 27 Flame Detection Probe or Photoelectric Sensor

[0239] 28 Electric Igniter or Resistor Igniter

[0240] 29 Flexible Gas and / or Liquid Fuel Lines

[0241] 30 Steel Extension Tube for Heating System

[0242] 31 Burner Control Box

[0243] 32 Ground insulation panel

[0244] 33 Heat exchanger volume

[0245] 34 Gravel for Drainage

[0246] 35 Vapor Extraction Tube

[0247] 36 High-Temperature Resistant Cables

[0248] 37 Catalytic oxydizer

[0249] 38 Compressor

[0250] 39 Plate heat-exchanger

[0251] 40 Front area of container

[0252] 41 Combustion head

[0253] 42 Flame

[0254] 43 Internal tube

[0255] 44 External tube

[0256] 45 Heating Element (tube)

[0257] Figure 1 shows a cross section of a additional module of a container.

[0258] Figure 2 shows a cross section in the length of a base container, showing the combustion chambers, the heat exchange volumes and the vapor recovery Figure 3 shows a cross section from the base module container Figure 4 shows a horizontal cross section at the bottom of a container, showing liquid recovery slots

[0259] Figure 5 shows the back to a container or an extension, showing the insulated opening panel for loading

[0260] Figure 6 shows an example of configuration with 3 containers and extensions

[0261] Figure 7 shows a vertical cross section of a container showing the extent of the insulated opening panel

[0262] Figure 8 shows the front area of the container, where the piping and monitoring equipment is located

[0263] Figure 9 shows the detail of the burner inside the combustion chamber as well as the combustion chamber

[0264] Figure 10 shows a cross section of the front area of the container with the inlet and outlets coming from the container

[0265] Figure 11 shows the front area with supporting ventilator, compressor and other equipment the mobilization of contaminants for efficient recovery for example by pumping.

[0266] Figure 12 shows an embodiment of the heating element.

[0267] EXAMPLES

[0268] To further illustrate the effectiveness and robustness of the invention, several practical experiments were conducted employing the containerized thermal treatment system with integrated vapor-phase oxidation. These pilot-scale applications confirm that the system is capable of achieving near-complete decontamination of PFAS-contaminated soils, in alignment with the technical objectives and inventive features described herein. The following examples provide evidence of operational success under real-world conditions, supporting the claimed destruction efficiency, system integration, and environmental sustainability.

[0269] Example 1. Thermal remediation of PFAS-contaminated soil.

[0270] A pilot test was conducted to demonstrate the efficacy of a containerized Thermal Conductive Heating (TCH) system with integrated vapor-phase PFAS destruction. Approximately 15,5 m3of PFAS-contaminated soil was treated in a fully insulated 20-foot container. Heating method: A remote flame burner fueled by propane gas elevated soil temperatures to a target of 350 °C, with burner surface temperatures reaching approximately 450 °C to ensure sufficient thermal conduction. PFAS vapor destruction: Vaporized PFAS compounds were routed directly into the flame of the remote flame burner, operating at 1400 °C, ensuring destruction during the reburn process.

[0271] Secondary safety measures: a vapor treatment unit (VTU) with two granular activated carbon filters (EcoSorb CS) was installed as a contingency, although modeling and preliminary measurements indicated near-complete combustion of PFAS vapors.

[0272] Results: Post-treatment soil samples confirmed a PFAS concentration reduction of more than 99,9%, achieving levels below the detection limit of 10 pg / kg for PFAS 4 (sum of PFOS, PFOA, PFHxS, and PFNA). No detectable PFAS or toxic degradation products were observed in emissions through non-target analyses.

Claims

38CLAIMS1. A heat production unit for use in a thermal remediation system for treating contaminated solids or waste, comprising a. a combustion head configured to mix a primary fuel with an oxidizer to produce a primary flame, wherein the oxidizer comprises an oxygen-enriched gas and the combustion chamber is operable at a temperature of at least 1200°C; b. a combustion chamber extending from the combustion head and positioned such that a substantial portion of the flame is located within or adjacent to said contaminated solids or waste; and c. a reburn inlet arranged to introduce vaporized contaminants into the flame tube.

2. The heat production unit of claim 1, wherein the integrated combustion chamber operates at a temperature of between 1400 °C and 1600 °C, and provides a residence time of at least one second for vaporized contaminants.

3. The heat production unit of claim 1, wherein the integrated combustion chamber operates at a temperature of between 1200 °C and 1400 °C, and provides a residence time of at least two seconds for vaporized contaminants.

4. The heat production unit of any one of the previous claims, wherein the reburn inlet is configured to introduce vaporized contaminants tangentially into the combustion chamber.

5. The heat production unit of any one of the previous claims, wherein the combustion chamber is lined with a refractory material.

6. The heat production unit of any one of the previous claims, wherein the combustion head comprises a fuel nozzle, an oxidizer inlet, and an igniter.

7. The heat production unit of any one of claims, wherein the oxidizer is provided by an oxygen-enriched gas stream supplied from an oxygen concentrator or liquid oxygen source, the oxygen concentration being in the range of 30% to 100%.

8. The heat production unit of any one of the previous claims, wherein the combustion chamber comprises turbulence-inducing elements, preferably swirl baffles or vanes.

9. The heat production unit of any one of the previous claims, wherein the combustion head is mounted in an adjustable manner within the combustion chamber, allowing control of the flame position relative to the contaminated material.

10. The heat production unit of any one of the previous claims, further comprising a control system that monitors the flame temperature, oxygen concentration,39 and the flow rate of vaporized contaminants, and automatically adjusts the fuel and oxidizer flow to maintain the flame temperature within a target range of l,400°C to l,600°C.

11. The heat production unit of any one of the previous claims, wherein the reburn inlet is connected to a vapor collection system configured to extract vaporized contaminants from the contaminated material and direct them into the combustion chamber.

12. A containerized device for the thermal treatment of contaminated solids and waste, comprising: a. at least one thermally insulated container; and b. at least one heat production unit according to any one of the previous claims, arranged within the container such that the combustion chamber is in thermal contact with the contaminated solids or waste.

13. The containerized device of claim 12, wherein the container is a modified ISO shipping container.

14. The containerized device of claim 12 or 13, wherein the containerized system further comprises an automated cleaning subsystem.

15. The containerized device of any one of claims 12 to 14 wherein the system is modular and designed for scalability through the deployment of multiple containerized units operating concurrently.

16. The containerized device of any one of claims 12 to 15, further comprising a vacuum pump configured to maintain an internal container pressure of between 100 mbar and 500 mbar.

17. A method of oxidizing contaminants in a thermal remediation process, comprising the steps of: a. initiating combustion of a primary fuel and an oxygen-enriched gas in a combustion head to produce a primary flame; b. directing the primary flame into a combustion chamber positioned within or adjacent to contaminated solids or waste; c. volatilizing at least a portion of the contaminants from the contaminated solids or waste; d. introducing the vaporized contaminants into the combustion chamber via a reburn inlet; and e. maintaining a temperature of at least l,200°C and a residence time of at least one second in the combustion chamber, thereby achieving near-complete oxidation of the contaminants.

18. The method according to claim 17, wherein the vaporized contaminants comprise per- and polyfluoroalkyl substances (PFAS), and wherein hydrogen40 derived from water vapor present in the contaminated material and from combustion promotes the mineralization of PFAS into hydrogen fluoride (HF), thereby reducing the formation of lighter fluorinated by-products.

19. The method according to claim 17 or 18, further comprising operating the thermal remediation process under sub-atmospheric pressure conditions to reduce the boiling point of the contaminants and enhance volatilization.

20. The method according to any one of claims 17 to 19, wherein the fuel-to- oxidizer ratio supplied to the combustion head is dynamically adjusted by a control system in response to real-time measurements of temperature and oxygen concentration to maintain the flame temperature within a target range.

21. The method according to any one of claims 17 to 20, wherein the combustion chamber is used concurrently to heat the contaminated solids or waste and to oxidize the vaporized contaminants, thereby improving energy efficiency and system integration.

22. The method according to any one of preceding claims 17 to 21, wherein all drained liquids can be reinjected at low flow rate into the combustion chamber to degrade the pollutants (PFAS) present in the liquids and operate without waste.

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