Even ten times smaller container installation is possible with EcoPro crossflow VOC incinerators, in comparison with competitive VOC oxidizers. This is enabled by the innovative, Compact design with two reactors side by side, and by the use of precious metal catalyst technology with fast reactions.
Container installation allows offering a ready product, saving weeks or months of installation and commissioning effort.
Best Available Technology is offered to comply with the tightest emissions regulations, with permanent VOC destruction efficiency up to 99,8+%. This is guaranteed by the new mixer type catalyst structure, which is four to five times more efficient than traditional cell structures .
The most commonly used VOC oxidation technologies are Themal oxidation and Catalytic oxidation. EcoPro Crossflow VOC incinerators based on the utilization of the catalyric oxidation technology. The use of the catalytic oxidation technology creates several technical and economic benefits over competing thermal oxidation technology.
The benefits of EcoPro Crossflow VOC incinerators
Over 99 % VOC elimination + 10 x energy savings + Ready product; save over 2 months commissioning + 10 x smaller; inside a container + Easy to install, easy to run + Plug and play; inside, outside or roof = Smart VOC emissions control systems by EcoPro.
Typically a temperature of 300°C for catalytic oxidation and 800°C for thermal oxidation is required for VOC oxidation. Therefore only about one third of energy is needed to heat VOC containing gas to the oxidizing temperature.
This enables a lower Auto Thermal operations without additional energy inputs with very low VOC content, even with less than 0.5 g/Nm³. So in many cases with catalytic oxidation, the support energy is only required during start-up.
Thermal vs. catalytic oxidation
Thermal and catalytic oxidators are the most common methods to fulfill VOC emissions regulations with incineration. Catalytic oxidation offers several advantages in comparison to thermal oxidation, especially with low VOC contents. The most important are cost savings, high purification, a compact size allowing easy installation, and cleanliness of the process. The quality and durability of catalysts has been significantly improved with Platinum Group Metal (PGM) catalysts which offer life times of more than 15 years.
EcoPro's crossflow heat exchanger enables efficient energy reuse and can be built for a very high heat recovery efficiency up to 96%. Mixing channel structure (Crossflow structure) of the regenerative heat exchanger is made of corrugated steel foil and has very high surface area and capacity in a small size. Nusselt number (Nu), which describes relative heat transfer efficiency, is four times bigger than in a straight channel.
EcoPro's crossflow catalyst structure enables extremely efficient mass transfer of molecules from the bulk gas into the micro pores of catalyst surface for reaction. Sherwood number, which describes structure mass transfer efficiency, is 12 in comparison to 2,5-3 with traditional cell structures. This guarantees maximal performance and purification result in minimal size. Conversion rate of even 99,9% is reached.
The EcoPro's concept to install two reactors side by side has eliminated internal pipe connections. Together with metallic structure and platinum group catalyst it has been possible to essentially reduce the size of the VOC oxidizer to one-fifth of thermal burners.
On the catalyst surface the reactions happen very fast. Gas residence time is ca, 0,07 s. Catalytic reactions are about 20 times faster than in the case of thermal oxidation. Also short residence time enables small sizing.
Thanks to the small size it is possible to install VOC oxidizer in a standard container, up to capacity 30.000 Nm³/h.
Crossflow noble metal catalyst
New generation noble metal catalysts can tolerate high temperatures and catalyst poisons so that over 15 year life cycle has been reached.
In oxidation catalysts the commonly used active metals are Platinum (Pt) and Palladium (Pd) which are dispersed in very small particles all over the huge coating surface. Today’s sophisticated coatings layers include optimized carrier structure, stabilizers and promotors. PGM (Platinum Group Metals) catalyst has high Pt and Pd loading. The higher the PGM loading the more active and durable the catalyst is. The similar chemical composition of catalysts is used in millions of cars and trucks. Catalysts are valuable also after the life cycle, as PGM’s can be recycled.
Residual emission formation is negligible in catalytic incineration. The higher the temperature the more Nitrogen and Oxygen contained in the air start to react together forming NOx. Thanks to the low operation temperature no NOx is formed. As a result of short residence time, proper oxidation happens quickly in low temperature and no other emissions like CO are born either. Also the need of supporting energy is minimal, so additional CO₂ generation is very small.
There are several techniques to clean industrial VOC-emissions (hydrocarbons), such as thermal- and catalytic incineration, condensing, adsorption and bio-dissolvement. VOC emissions need to be treated because the cause serious health hazards and harm the nature. According to IPC they are in average 11 times more harmful greenhouse gases than CO2. Most commonly know of them are methane, which is 25 times and halogenated hydrocarbons, which are up to thousands of times more harmful than CO2. Therefore, the emission standards almost everywhere are tightening.
European emission directive 1999 EY/13 originally disposed emission limits according to target areas. Originally the tightest limit was 50 mg/Nm3. However, directive allows local authorities to set tighter limits. Nowadays in EU, the most common limit is 20 mg/Nm3 but in some countries and cases it can be even 5 mg/Nm3.
Most commonly used techniques used are thermal and catalytic incineration, thermal incineration being the most popular.
Catalytic VOC-incinerator vs. thermal incineration
Since VOC-concentrations are generally quite low, the incineration requires an effective heat exchanger and often also support energy. Regenerative heat exchanger is the most effective solution for this. They have two heat reserves, of which in turns one is heating the incoming gas and the other is collecting heat. Thermal incineration requires about 800 °C temperature and catalytic about 500 °C lower. This is the reason for catalytic incineration becoming more popular.
EcoPro catalytic Crossflow VOC-incinerator vs. thermal incinerators
EcoPro catalytic product family is called with name Crossflow. EcoPro Crossflow VOC-incinerator family consists of six standard products, which cover capacities from 1300 Nm3/h to 30.000 Nm3/h. This product family cover about 80% of the demand. Bigger products are engineered and manufactured tailormade for each case. Standard products are designed so, that they fit in one 20’ sea container and they can be transported as economical container freight. These incinerators are ready for plug and play and they have clear installation- and user manuals. Also, installation and commission guidance is available when necessary.
All regenerative thermal incinerators are, minimum five times bigger than EcoPro Crossflow VOC-incinerator. Thermal incinerators have to be transported to installation site in pieces and assemble on site. The reasons for much larger size are higher running temperature which leads to need for larger heat exchanger and require, about 15 times longer burning time. In thermal incineration burning time is about 1 second and in catalytic incineration it is 0,07 second respectively. Additionally, the size difference is affected also by using ceramic heat exchanger material in thermal incineration. Due to bigger size the emissions released during direction change are bigger. This limits the efficiency of two exchanger (twin bed) incinerators to approx. 96 – 98 %. For tighter emission limits thermal incinerators require so called third bed, which will rise the costs significantly.
EcoPro catalytic Crossflow VOC-incinerator can reach, when necessary, even over 99 % efficiency in VOC destruction. High conversion rate and heat exchanger efficiency are guaranteed by mixing structure (=crossflow) in both heat exchangers and noble metal catalysts. The whole reactor is made of stainless steel.
About EcoPro Crossflow catalysators
In EcoPro VOC-incinerators proven noble metal activated catalysts are used. Oldest of these have been installed to VOC-incinerators over 20 years ago and are still functioning well. Decades of experience of these catalysators has been obtained in cars. The noble metals used, platinum (Pt) and palladium (Pd) are very durable against many toxic substances. Nevertheless, there are some limitations to VOC-emissions. These are heavy metals and silicone substances. These catalyst poisons do not react with noble metals but cover them.
Valuable noble metals can relatively easily be recycled. Most of the impurities deactivating the catalyst can also be removed by acid / alkali washing. Both catalyst and heat exchanger structures are modular, which enable them to be checked and maintained.
About autothermal point (ATP)
Thanks to lower running temperature and Crossflow heat exchanger, EcoPro Crossflow VOC-incinerators can function in lower VOC-concentrations without support energy, which means that their autothermal point (ATP) is low. The following calculation example concretizes the importance of the ATP. If VOC-concentration is below 0,6g/Nm3, the 30.000 Nm3/h thermal incinerator requires 33 – 48 kg/h more support fuel. In 3 shift operation this means 26,4 – 38,4 tons per year.
About the size of the acquired unit
When acquiring a unit belonging to standard product series, the unit is almost always bigger than the actual need at the time. The bigger unit then offers as benefit, lower pressure loss, electrical consumption and lower auto thermal point. 25% overcapacity lowers the auto thermal point approximately 17 % and 50 % overcapacity approximately 29 % meaning that ATP can be as low as 0,45 g/Nm3.
As a guiding line, in the design of EcoPro Crossflow VOC-incinerators, has been to create possibility for multipolar VOC-emission elimination. In such case expensive piping network construction can be avoided. Each unit is only functioning when needed. Also if there is requirement to re-arrange production, multipolar system is flexible.
Gas flow inside EcoPro Crossflow VOC incinerators:
Gas flow inside EcoPro Crossflow TB VOC incinerators
Gas flow inside EcoPro Crossflow LV VOC incinerators