Tri-Mer Corp., a developer of advanced technologies for the control of volatile organic compounds (VOCs), fine particulate and industrial gases, has introduced UltraTemp Filtration, a hot gas filtration system that filters fine particulate to extremely low levels. The heart of the system is a new generation of ceramic filters.

Previous ceramic filters (sometimes called "candle" filters) were manufactured from high-density granular powders similar to common ceramic products. While effective, they were brittle and had low thermal shock resistance, so they were prone to cracking and breakage from thermal shock. As a further drawback, these older ceramic filters were sometimes hard to keep clean under continuous operation.

Fiber Benefits

Now, with advances in fiber and ceramic technology, these issues have been overcome. The filters used in the UltraTemp Filtration system are manufactured from a new generation of low-density ceramic fibers that provide high resistance to thermal shock. This makes the filters very ductile and resistant to crack formation.

The unique composition of the ceramic fibers give the UltraTemp filters an exceptional ability to capture fine particulates at the fiber surface, without blinding. They are thus easy to clean using standard pulse-jet techniques. Being fibrous, rather than granular, the filter elements are also lightweight and very robust for installation and handling. They have high porosity with low resistance to flow, which minimizes the number of elements required for a given application.

The UltraTemp Filtration system provides optimal filtration for gases between 400°F and 1000°F and, in most cases, can be applied to hot gas streams up to a maximum operating temperature of 1650°F. Typical filtration results are 0.001 grain/dscf (2 mg/Nm³); many results are a fraction of this typical value.

UltraTemp Filtration is compatible with heavy inlet loadings, often above 1 grain/dscf (2300 mg/Nm³). Certain applications involving three or four times this inlet loading still achieve outlet levels of less the 0.001 grains/dscf. The ceramic filters are almost completely chemically inert and highly corrosion-resistant.

Potential Applications

Enlarge this picture Figure 1. UltraTemp filtration system for control of particulate, SO2 and NOX.

Applications of the UltraTemp Filtration system include syngas cleaning, glass production, waste incineration and biomass pyrolysis. Other applications include metal smelting, mineral processing and chemical production. UltraTemp Filtration is also suited for ICI boiler MACT compliance for coal, biomass and wood.

The UltraTemp Filtration system features an option for the dry injection of calcium- or sodium-based sorbents for the capture of acid gases. Injected in the duct upstream of the filter modules, the additional sorbent particulate is easily captured along with its pollutant gas. For these applications, SO₂ removal is typically 80% or better, with removal efficiencies as high as 97%. HCL removal is typically 95% and often as high as 99%.

If the need is NO_x, VOC or dioxin removal, UltraTemp filters are available with embedded catalysts. Urea is then injected upstream of the filters. NO_x removal in these systems is typically above 90%, and VOC oxidation and dioxin removal are also both exceptionally high. UltraTemp Filtration can incorporate both sorbent injection and catalyst reduction in a single system. Acid gases, such as SO₂, and NO_x can be simultaneously removed in the same system (see Figure 1).

The UltraTemp system uses a baghouse configuration with a reverse pulse-jet cleaning action. The filters are back-flushed with air, inert gas, syngas or other appropriate gases. The system has a reliable sealing mechanism that is easy to access, and the design has been engineered for easy installation and maintenance. Filter elements are manufactured in various sizes, the largest of which is 10 ft long and 6 in. in diameter, including an integral mounting flange.

The UltraTemp Filtration system is an efficient, proven approach for hot gas filtration. With over 400 applications worldwide, it is now commercially available throughout the U.S. with full technical and start-up support. 

For more information, contact Tri-Mer Corp. at (801) 294-5422, e-mail kevin.moss@tri-mer.com or visit www.tri-mer.com.