Smashing the costs of removing gaseous emissions and dust

June 22, 2015 KARSTEN POULSEN

A game-changing filter bag based on catalytic technology provides significant CAPEX and OPEX reductions.


FLSmidth and Haldor Topsoe representatives gathered at Haldor Topsoe Head quarter in Lyngby, Denmark during the signing ceremony, January 2015

FLSmidth has teamed up with the Danish catalyst specialist Haldor Topsoe to release a new type of filter bag. Called CataFlex™, it is capable of removing ammonia, nitrogen oxides, volatile organic compounds and dust in one integrated and cost-effective process. It has been designed for use at cement plants, but it can just as easily be used in power production, biomass, waste incineration, glass and metal production, and similar.

The key differentiating factor about the patent-pending catalytic filter bag lies in its three layers of filter fabric. Each layer contains a tailored catalyst optimised for the removal of specific kinds of compounds from the off-gas that passes through it. 

Fabric filters are used across a variety of different industries as they are very efficient in securing emissions at extreme low dust levels. In many applications, they are used as a final purification step to remove particulate matter from the flue gas. FLSmidth is a market leader in this field with extensive experience and in-house knowledge on how to design, manufacture and operate fabric filters. 

Read more about catalytic solutions here>>

Reduced CAPEX and OPEX
Capable of removing ammonia, nitrogen oxides, volatile organic compounds and dust in one cost-effective process, CataFlex provides compelling opportunities for CAPEX savings (initial investment needed) and OPEX savings (ongoing operating cost). Since the filter bag requires less space than alternative solutions, it also provides opportunities to reduce the physical footprint.

 “We believe the catalytic filter bag will be a game-changer because it enables cement plant owners to clean industrial off-gases and meet stricter legislation at a fraction of the cost compared with best available technologies today.” - Ole Bøegh, CEO, FLSmidth Air Pollution Control

Ole Bøegh explains the bag’s uniqueness: “It doesn’t just provide us with the flexibility to tailor different catalytic combinations for different industries; it also makes it possible to handle the removal of several critical compounds in one integrated process. This can significantly reduce the cost of off-gas cleaning. Remember that today’s standard is to use separate stand-alone systems to remove specific compounds.” 

Fast-tracking innovation potential 
Denmark-based Haldor Topsoe is a highly successfully manufacturer and researcher within catalysis and surface science. Over the past four years, FLSmidth and Haldor Topsoe have worked closely together on developing the patent-pending CataFlex™ technology. The product has been thoroughly tested and proven efficient for several industrial applications.

Key to the development of this unique product is the combination of FLSmidth's expertise and market leadership in filters for industrial processes as well as process integration and Haldor Topsoe’s leadership in catalysis.  

“Developing this product has been a combination of the very best that Topsoe and FLSmidth have to offer from an R&D perspective. By combining FLSmidth's expertise in filtration in industrial processes with Topsoe’s leadership in catalysis, we have created a unique product that will allow customers to meet increasingly stringent environmental legislation” says Bjerne S. Clausen, CEO at Haldor Topsoe.

Thomas Schulz, CEO of FLSmidth says, “It is an imperative for FLSmidth to retain technology leadership with innovative new solutions increasing energy efficiency and lowering cement plants’ environmental impact at a competitive lifecycle cost.”

He adds, “The CataFlex™ catalytic filter bags will enable cement plants to upgrade their environmental equipment to fulfill tightened legislation at low cost and with minimum influence on existing production equipment.” 

Efficient removal of gaseous emissions and particulate matter
Whereas a normal filter bag is a one-layer filter of textile, CataFlex has a three-layer porous woven structure with various catalyst formulas customised for each layer through which gases are sent, leaving the dust on the outer surface and removing the gaseous pollutants when passing through the layers. Typically, the filter bags are six to ten meters long and have a diameter of 127 mm.


​Embedded catalyst in woven fiber glass bag

It will easily remove dust below 5mg/Nm3. At the same time, it converts nitrogen oxides (NOx) and ammonia (NH3) into harmless nitrogen (N2) and water (H2O). Organic hazardous air pollutants (O-HAP), including toluene, benzene and formaldehyde, are converted into carbon dioxide (CO2) and water (H2O). Dioxin, furans and CO are also removed if it is present in the flue gas.

Read more about Full-Scope reduction of NOx and SO2 here>>

Immediate opportunities in the US
“Initially we believe the US market will benefit from the product, because cement producers here are faced with immediate challenge in order to meet new regulatory requirements that have been issued by the US Environmental Protection Agency and will take effect 1 September 2015,” says Thomas Schulz, CEO at FLSmidth. 

He points out that, in the longer term, China may hold an even greater market potential as the country is also imposing stricter emission legislation. 

As part of the agreement between FLSmidth and Topsoe, the new product will be manufactured at FLSmidth’s bag production facilities in Georgia, USA. The high quality filter bags will then be embedded with catalyst and assembled at Topsoe’s catalyst production site in Houston, Texas.

Read more about FLSmidth and particulate emission control>>

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