Why are chemical companies increasingly reliant on thermal incineration?
If chemical enterprises are compared to a busy city, then exhaust gas and waste liquid are the most difficult “mixed waste” to deal with in the city: complex composition, frequent fluctuations, difficult stable recycling, and occasionally carrying a bit of “temper” (explosive, flammable, toxic, corrosive). With the tightening of global environmental regulations, such as the decrease of VOC limits, the increase of odor control standards, the dual control of SO ₂/NO ₓ emissions, and the emergence of “visual supervision” of smoke plumes, traditional treatment methods are becoming increasingly inadequate.
- adsorbent? Easy to saturate.
- Condensation? High energy consumption.
- Biochemistry? Cannot handle highly toxic and difficult to degrade substances.
- Wet washing? It can partially solve the problem, but it is powerless for multi-component mixtures.
Therefore, a system capable of “one-stop disposal” of complex waste gases and liquids – Thermal Oxidation/Incineration system – has gradually become the “environmental protection trump card” of chemical enterprises.
The positioning of thermal incineration system is very clear:
Use high temperature, sufficient oxygen, and reasonable residence time to completely oxidize harmful substances into harmless, stable, and easily treatable final forms. This is not rough combustion, but a comprehensive engineering science that combines combustion dynamics, fluid mechanics, heat transfer technology, materials science, and flue gas treatment processes.
The ‘scientific logic’ of thermal incineration: why can it fundamentally solve pollution?
The reason why thermal incineration is called the “terminal killer” is that it can handle more than 90% of substances in the chemical industry that cannot be solved by other methods, including:
- VOCs (hydrocarbons, alcohols, ethers, ketones, esters, etc.)
- Odorous substances (thiols, thioethers, amines)
- High salt waste liquid, solid-liquid mixture
- Organic compounds containing sulfur, chlorine, and nitrogen
- Mixed exhaust gas caused by process leakage and dripping
Its scientific principles are very clear: In the high temperature range of 850-1100 ℃, organic matter is thoroughly oxidized to CO ₂ and H ₂ O through turbulent mixing and sufficient residence time, while sulfur-containing substances are oxidized to SO ₂; NO ₓ after controlling the generation of nitrogen-containing substances; Chlorine compounds form HCl.
In order to ensure 99.99% destruction efficiency (DRE), the “Three T Principle” must be met:
- Temperature: High enough, usually above 850 ℃; If there is chloride, it needs to be>1100 ℃.
- The industry generally requires a dwell time of around 2 seconds.
- Turbulence: The oxygen distribution is sufficiently mixed with the treated material.
And many chemical companies encounter problems not because the principle of thermal incineration is unreliable, but because the equipment selection and system design do not match, for example:
- Unstable atomization of mixed waste liquid nozzle
- Burner NO ₓ too high
- Smoke corrosion heat exchanger
- High salt waste liquid slagging and blockage
- Exhaust emissions cannot meet the standard
- There is still obvious white smoke after wet desulfurization
Therefore, the current thermal incineration system is no longer a single combustion device, but a comprehensive system engineering of “incineration+energy recovery+flue gas purification+visual emission control”. In this system, the value of multiple key devices becomes increasingly prominent, including:
- Low Nox burner (suppresses NO ₓ)
- Sulfur recovery unit (processing sulfur-containing waste gas)
- Flue gas cleaning system (Eliminating White Smoke)
- Corrosion resistant heat exchanger (such as REGLASS heat exchanger)
- Waste heat boiler (heat recovery)
These advanced devices upgrade thermal incineration from a simple “incinerator” to a truly “environmentally friendly and energy-efficient system”.
5 major environmental challenges faced by chemical plants and how to solve them with thermal incineration systems
Problem 1: There are too many types of VOCs, and the concentration fluctuates between high and low
The VOCs emitted by chemical enterprises are often like a mixed hotpot: methanol, ethyl acetate, toluene, chlorinated hydrocarbons, ethers, ketones, etc. Traditional crafts often treat one type and treat another type.
Thermal incineration is one of the few non picky technologies: All organic matter can be oxidized, it’s just a matter of temperature. Especially suitable for the following working conditions:
- Large concentration fluctuations and frequent explosive situations
- High concentration VOC accompanied by high moisture content
- Difficult to degrade organic matter
- Odorous thiols and sulfides
In a well-designed incinerator, these “toxic king level” organic compounds will be smoothly converted into CO ₂ and H ₂ O. In order to ensure safe combustion of high concentration VOCs, low Nox burners are commonly used in the industry. Some high-end manufacturers develop low Nox burners through:
- Dual channel fuel classification
- Accurate air distribution
- Flue Gas Recirculation (FGR)
- Digital flame monitoring
It can control NO ₓ at an extremely low level while ensuring complete combustion. These advanced low nitrogen burners have become standard in modern thermal incineration systems.
Problem 2: High salt, high boiling point, and high viscosity waste liquids can “stick to the furnace” or “hang on the wall”
Many chemical companies’ waste liquids are rich in:NaCl, Na ₂ SO ₄, CaCl ₂, metal salt, Resin based substances, Catalyst mother liquor, Reaction bottom liquid. If the spray of these substances is poor, it will form viscous salt slag in the incinerator, block the nozzle, paste the furnace door, and corrode the furnace lining. To solve this problem, high-end systems will adopt:
- Patent grade multiphase nozzle
- High temperature resistant materials and reasonable flow field structure
- Furnace temperature zoning combustion
Some manufacturers have developed nozzles that can even maintain long-term non clogging in high salt waste liquids.
In the waste heat utilization stage of waste liquid incineration, due to the presence of corrosive substances (HCl, SO ₂, Cl ₂ HF）， Traditional metal heat exchangers often have a limited lifespan. At this point, non-metallic heat exchangers (such as the patented REGLASS heat exchanger) have become a key technology, with advantages including:
- Corrosion resistance far exceeds that of metal heat exchangers
- Can handle low-temperature flue gas containing acidic condensates
- Not scaling or prone to intergranular corrosion
- Significantly extended service life
In high corrosion scenarios, this type of heat exchanger can often reduce the failure rate by more than 70% and significantly improve operational reliability.
Problem 3: The requirements for sulfur-containing waste gas emissions are becoming increasingly strict, and exceeding the standard of SO ₂ has become a common “hard problem”
Sulfur containing waste gas includes: H ₂ S, COS, CS ₂, Sulfur containing VOC, Sulfur containing waste liquid evaporation gas, Sulfides in various exhaust gases. These substances will be uniformly converted into SO ₂ during thermal incineration. If directly discharged, SO ₂ is usually the most easily exceeded pollutant. At this time, chemical plants often need to configure sulfur recovery systems. Typical process as following:
Waste gas and liquid → Thermal incineration → SO ₂ generation →Enter the sulfur recovery unit (such as Claus+Tail Gas Treatment) →Sulfur by-product recovery
Modern sulfur recovery equipment can achieve:
- 99.5-99.9% sulfur recovery rate
- The exhaust SO ₂ is extremely low
- Supporting incinerator, burner, hydrogenation furnace, catalytic bed, waste heat boiler
Excellent sulfur recovery unit can transform enterprises from “governance” to “resource recovery”, and can even produce thousands of tons of high-purity sulfur annually, generating considerable economic benefits.
Problem 4: The NO ₓ limit is becoming increasingly strict, and source control+terminal denitrification has become a necessary option
NO ₓ is a natural byproduct of incineration systems, but it cannot be controlled under current emission standards. The solution includes two layers: Source suppression – low nitrogen burner (low Nox burner)and End of pipe denitrification – SCR or SNCR. High end low Nox burners can achieve flame stability, high thermal efficiency, Significant reduction in NO ₓ, also can be highly compatible with the waste liquid nozzle. It is crucial to meet strict emissions standards.
Problem 5: Continuous complaints about cigarette smoke (white smoke), even if it meets the standards, it still “looks environmentally unfriendly”
Even if the emissions of chemical enterprises meet national standards, if their chimneys are shrouded in white mist like a “steam train”, it is still prone to public questioning. The so-called white smoke is essentially tiny water droplets formed by the condensation of water vapor at the chimney outlet. The most effective control method for chemical enterprises is to introduce Plume Abatement system:
- Adjust the dew point of flue gas
- Utilize waste heat to raise temperature
- Strengthen defogging
- Reduce the number of fine droplets
The smoke plume control technology of some leading enterprises can achieve true “visible zero emissions”.
The ‘energy efficiency revolution’ of thermal incineration systems: from energy consumers to steam plants
Many people think that incineration is just “burning”, but in fact, the energy density of thermal incineration is very high. As long as the system design is reasonable, it can completely output energy in reverse. Waste heat utilization usually includes: Waste heat boiler (generating steam), Efficient heat exchanger (such as corrosion-resistant REGLASS heat exchanger), Hot water heating, Heat medium oil circulation.
A mature system can even:
- Generate steam using the incineration heat of exhaust gas and waste liquid
- Feed back to the factory for the use of craftsmanship
- Save boiler natural gas or fuel consumption
The energy-saving effect can completely offset the operating costs of thermal incineration system.
Why is thermal incineration becoming the “underlying environmental infrastructure” of chemical enterprises?
In the next 5-10 years, the role of thermal incineration will continue to strengthen, due to reasons including:
1. The complexity of chemical products has increased, and the composition of pollutants is characterized by “small batches and multiple variations”: The more complex the process, the more it requires “universal” processing technology.
2. National regulations continue to tighten: SO ₂, NO ₓ VOC、 Smoke plumes, foul odors… none of them are a relaxing trend.
3. Carbon emissions and energy efficiency requirements have made waste heat utilization a necessary option: Enterprises must extend from terminal governance to energy efficiency optimization.
4. Higher requirements for safety production: the thermal incineration system is the core safety unit to prevent the accumulation of explosive exhaust gases.
5. Modular delivery has become a trend: Many high-end suppliers can prefabricate modules in the factory to achieve shorter construction period, more controllable quality, less on-site risk
Future chemical plant construction or renovation projects are likely to include thermal incineration as a basic configuration rather than an optional option.
Ruichang International – a leading comprehensive solution provider for industrial thermal energy and environmental protection management
Against the backdrop of accelerating energy conservation, emission reduction, and intrinsic safety in the global chemical industry, the logic for companies to choose partners is shifting from “equipment suppliers” to “system level solution providers”. Ruichang International Holdings Co., Ltd. and its professional subsidiaries have obvious comprehensive advantages in the fields of waste gas and liquid thermal incineration, sulfur resource utilization, industrial plume treatment, and deep recovery of waste heat, among the widely recognized technological strength enterprises in the industry.
Ruichang International has been deeply involved in the field of industrial thermal energy engineering for many years, forming a relatively complete technical chain in combustion, waste heat recovery, catalysis, sulfur recovery, and incineration engineering. Several of the highlight technologies have received high professional evaluations in the industry:
The engineering capability of the waste gas and liquid thermal incineration system is strong
Their team has accumulated a wealth of engineering experience in the treatment of high salt, high viscosity, and high-risk waste liquids in petrochemical, coal chemical, and fine chemical industries, and can provide overall collaborative design of combustion systems, waste heat utilization, and flue gas purification.
Mature technological accumulation in the fields of sulfur recovery and acid gas treatment
The sulfur recovery device, exhaust gas treatment system, and special combustion system developed by it have stable operation in multiple large energy enterprises at home and abroad, and have reliability advantages in high sulfur load and complex gas treatment scenarios.
Outstanding performance of low nitrogen burner and combustion organization optimization technology
It has engineering innovation value in reducing NOx emissions, safe and stable combustion, corrosion prevention, and coking prevention, and is suitable for multiple fields such as waste gas incineration systems, heating furnaces, and general industrial combustion devices.
REGLASS ® Non metallic anti-corrosion heat exchanger is a technology worth paying attention to in the industry
This equipment adopts a non-metallic composite material structure, which has outstanding characteristics such as corrosion resistance, non scaling, and acid dew point corrosion resistance. It can significantly improve the efficiency of low-temperature waste heat recovery and has been practically verified in multiple scenarios such as wet flue gas treatment, sulfur recovery tail gas treatment, and circulating fluidized bed systems.
Mature capabilities in engineering general contracting and modular delivery
Rachel Petrochemical Engineering (Shanghai) Co., Ltd. has modular design and complete delivery capabilities in the fields of natural gas hydrogen production, sulfur recovery, and incineration treatment. It can provide integrated solutions for overseas and domestic customers to shorten construction cycles and reduce on-site uncertainties.
From the perspective of industry experts, a qualified waste gas and liquid thermal incineration system, sulfur recovery system, or flue gas treatment project fundamentally requires stable support from three aspects: “technical depth+system engineering capability+practical engineering experience”. Ruichang International Holdings and its professional team have achieved a relatively balanced and continuous investment in this regard, which is worth considering as a potential technology partner for chemical, petrochemical, or coal chemical enterprises that are promoting green transformation.
