DEC.CTO™

Catalytic Thermal Oxidizers

DEC IMPIANTI S.p.A. is a private corporation, focused on engineering and supply of turn key sustainable industrial VOC and HAP emission control systems for the flexible packaging, chemical, petrochemical and pharmaceutical industries. Backed with 75+ years of global experience, thanks to products of the highest quality, patented and/or innovative processes, with thousands of systems in operation, we are facing the global challenges, focusing on innovative sustainable technologies and research.

Whenever you have to face a non-recoverable stream of VOCs, a XTO™ • thermal oxidizer could be the solution. Sometimes the VOC stream composition may result too complex to be recovered or the quantity of solvents is not interesting to go for a SRU™ • solvent recovery units.

DEC.CTO™ • catalytic thermal oxidizers

DEC.CTO™ (Catalytic Thermal Oxidizers) refers to a specific configuration of a thermal oxidizer system (XTO™): in a CTO, we apply a combination of high temperatures and catalytic materials to achieve pollutant oxidation and conversion into less harmful byproducts. The catalyst is a material that speeds up the reaction without being consumed itself; common catalysts used in catalytic oxidizers include platinum, palladium, and rhodium.

The basic operation of a catalytic thermal oxidizer involves three main steps:

Preheating: The incoming polluted gas stream is preheated as it passes through a heat exchanger. The purpose of preheating is to reduce the energy consumption required to reach the desired oxidation temperature.

Catalytic Reaction: The preheated gas stream then enters the catalytic chamber, which contains a catalyst material. The catalyst is typically made of precious metals such as platinum, palladium, or rhodium, supported on a high-temperature stable material like ceramic or metal. The catalyst promotes the chemical reaction between the pollutants and oxygen at lower temperatures than in a non-catalytic thermal oxidizer. This lower temperature operation is one of the key advantages of catalytic thermal oxidizers.

Post-Treatment: After the catalytic reaction, the gas stream passes through a post-treatment system, which may include additional treatment units like heat recovery systems, scrubbers, or carbon filters. These units help remove the remaining pollutants, recover heat energy, or further clean the gas stream before it is released into the atmosphere.

DEC, DEC IMPIANTI, catalytic thermal oxidizer, catalytic oxidizer, catalytic incinerator, air pollution control, pollution abatement technology, VOC abatement, HAP treatment, industrial emission control, high-temperature catalyst, precious metal catalyst, energy-efficient oxidation, low-temperature oxidation, emission reduction solutions, pollution control equipment, environmental compliance, industrial process emissions, heat recovery systems, gas stream purification, airborne pollutant removal, oxidation equipment, GHG, CO2, NOx, CO, N2O, direct-fired thermal oxidizer, afterburner, industrial exhaust treatment, Volatile organic compounds, Hazardous air pollutants, Emission control system, Pollution abatement, Combustion chamber, Destruction efficiency, Heat recovery, Exhaust gas treatment, Energy efficiency, Furnaces, CTO, XTO, TOX, VOC, HAP, used Thermal Oxidizer, Thermal Oxidation, Thermal Oxidizer Service, Thermal Oxidizer Repair, Thermal Oxidizer Maintenance, oxidiser, MACT, BACT, RACT, EPA, Title V Permit, Destruction Efficiency, 99% Destruction Efficiency, Combustion, Combustion Controls, environmental services

DEC.CTO™ • oxidation reaction

The oxidation reaction is:

VOCs (C_xH_yO_z) + O₂ + thermal energy = CO₂ + H₂O + (HEAT)

The heat is usually recovered to pre-heat the SLA stream, in order to save on "thermal energy" (provided through gas CH₄ - methane); if producing extra heat through oxidation of solvents, an energy recovery system shall be foreseen (typical applications are ranging from heating up air for dryers, steam production, heat tranfer fluid heating, water heating - industrial or sanitary, etc.).

DEC.CTO™ • pros and cons

The advantages of catalytic thermal oxidizers include:

Lower Operating Temperatures: Catalytic oxidation allows for operation at lower temperatures (for VOCs, typically ≤450°C) compared to non-catalytic thermal oxidizers (e.g. DTO™ or RTO™). This reduces energy consumption and can be advantageous for heat-sensitive or low VOC concentration applications.

Higher Efficiency: The presence of a catalyst enables more efficient oxidation of pollutants, resulting in higher destruction efficiency and lower emissions.

Reduced Fuel Consumption: The lower operating temperatures of catalytic thermal oxidizers can lead to reduced fuel consumption, resulting in cost savings.

Wide Applicability: Catalytic thermal oxidizers can effectively treat a wide range of pollutants, including VOCs and HAPs, making them suitable for various industrial applications.

It is important to note that the catalyst material in a catalytic thermal oxidizer may require periodic maintenance or replacement due to catalyst deactivation or degradation. Catalysts can also be susceptible to poisoning: this occurs when a substance in the gas stream binds to the catalyst and prevents it from functioning properly.

When a catalyst is poisoned, it can lead to a number of problems, including:

Decreased performance: The poisoned catalyst will not be as effective at promoting the oxidation of pollutants, leading to increased emissions.

Increased operating costs: The poisoned catalyst will need to be replaced more frequently, leading to increased maintenance costs.

Safety hazards: Poisoned catalysts can generate heat, which can lead to fires or explosions.

The first step is to identify the source of the poisoning: this can be done by analyzing the gas stream for potential poisons and once the source of the poisoning has been identified, it can be eliminated. In some cases, it may be necessary to replace the poisoned catalyst, leading to costly repairs and downtime.

thermal oxidation | incinerators • GHG and by-products

An oxidizer is handling the transformation of the pollutant(s) into different products, with a reduced environmental impact. However, it is important to consider the resulting GHG emissions, when selecting a VOC oxidizer; the amount of GHGs generated by a thermal oxidizer depends on the type of VOCs being treated, its quantity, the needed quantity of fuel to be added for sustianing the oxidation reaction and the selected oxidizer process configuration.

VOCs (C_xH_yO_z) + O₂ + thermal energy = CO₂ + H₂O + (HEAT)

Any oxidizer will have to deal with all or most of the following issues:

VOCs emission (= non complete oxidation);

CO₂ emission (= GHG, possible taxation);

CO emission (= GHG, non complete oxidation);

NO_x emission (= nitrogen oxides, as a result of N₂ presence);

N₂O emission (= nitrous oxide);

Dioxin emission (as a result of possible chlorinated compounds );

High temperature emission (as a result of non complete thermal energy recovery).

These emissions contribute to climate change and should be taken into account when assessing the overall environmental impact of the system.

As mentioned earlier, oxidizers typically require a significant amount of energy to operate: if this energy comes from non-renewable or carbon-intensive sources, it will dramatically contribute to environmental degradation and offset any of the potential benefits of VOC emission reduction.

thermal oxidation | incinerators • greenwashing

Greenwashing will occur when a company promotes an oxidizer as an environmentally friendly or sustainable technology for VOC emissions control, while neglecting to address other significant negative aspects of its environmental impact, such as greenhouse gas (GHG) emissions and harmful by-products.

Greenwashing can happen when a company portrays an oxidizer as a comprehensive and eco-friendly solution to VOC emissions, creating the perception that it is a sustainable option without considering the complete environmental picture. While oxidizers can help reduce VOC emissions, they can have negative consequences that should not be overlooked.

To avoid greenwashing, companies shall provide transparent and comprehensive information about the environmental impact of their VOC emission control systems: this includes addressing greenhouse gas (GHG) emissions, harmful by-products, and the energy efficiency of the system. By doing so, companies can ensure that consumers have an accurate understanding of the technology's environmental implications and make informed decisions.

the concept of greenwashing comes into play when a company portrays an oxidizer as environmentally friendly or sustainable technology, even though it is not green and environmentally friendly as claimed: in the context of oxidizing VOCs, greenwashing can occur when the use of an oxidizer is advertised as a comprehensive and eco-friendly solution to VOC emissions, while ignoring other significant negative aspects of environmental impact, such as GHG and by-products.