Herding GmbH Filtertechnik

The Herding® ALPHA filter is a dry filter system designed for a maximum operating temperature of 450° C. The filter unit is a round filter with a welded design, suitable for an operating pressure of +/- 250 mbar.

The filter housing can be designed as gas-tight version or as pressure vessel. The materials used depend on the application.

The ALPHA filter (cluster) used is a high temperature resistant barrier filter on the basis of a mineral matrix. The material has excellent chemical resistance even with at higher temperatures. In addition to their excellent fire-proof properties the filters have also a high temperatures shock resistance. The ALPHA filter clusters are installed vertically or horizontally in the filter housing from the clean gas side. This allows a compact, space-saving design and greatly simplifies the installation.

The filter elements which are arranged in groups are sequentially cleaned online by using a jet-pulse system.

Benefits:

- Stable filtration performance at low pressure drops

- Permanently temperature-resistant up to 450° C

- Excellent filtration efficiency

- Compact design, high ratio of filter surface per volume

- Non-combustible, chemically stable

Specifics:

The Herding® ALPHA filter system is especially suitable for incineration, combustion and drying processes and pyrolysis of biomass.

Herding Filtertechnik, the specialist for innovative filter systems, has managed to create an ultra-compact filter system for the efficient extraction of dust at all stages in a very wide range of processing lines – the Herding FLEX.

This means that all the filter units in a production line can be operated and maintained easily and at low cost. A safe disposal system for all the different types of dust via a central system can be integrated without any problems.

The core feature of the Herding FLEX generation of filters is the inherently rigid sinter-plate filter – a patented in-house development. Pure surface filtration ensures that even ultra-fine dust particles are reliably retained. The sintered rigid body is extremely hard-wearing against abrasive solids and also against mechanical and chemical loads. In terms of durability the sinter-plate filter lasts well over 10 years, depending on the specific process. Adhesive solids are effectively prevented from sticking to the filter surface by automatic precoating. For explosive atmospheres a range of structural and preventive explosion protected versions are also available.

The Herding FLEX series enables extremely efficient dust extraction for volumetric flows of up to 400,000 m³/h. The sinter-plate filter offers outstanding cleaning properties and constant pressure loss for stable extraction performance of the highest standard. The dust discharge can be configured to meet all safety-relevant requirements.

Herding MAXX filter units with the Herding sinter-plate filters are generally suitable for the filtration and product recovery of fine, abrasive and adhesive dusts or for dusts with agglomerating tendencies. The Herding MAXX series is perfectly conceived for large product quantities with flow rates up to 1.000.000 Am³/h and more.

The Herding MAXX series offers all the proven benefits of pure surface filtration with Herding sinter-plate filters for use in large volume flows.

The actual dust particle separation is achieved via the patented Herding sinter-plate filters by pure surface filtration on a rigid-body basis.

The modular concept allows the most effective use of space during transport and delivery, as well as high flexibility in plant construction. Depending on the existing site conditions, the bolted construction concept offers several alternatives from basic components to large, pre-installed assemblies.

Application areas are the steel manufacturing, sand mining and processing, ore extraction, processing and transport as well as recycling and treatment technology. Other application areas of the Herding MAXX series can be found in the glass, chemicals, metallurgy, food, and e.g. the plastics industry.

The Herding PHARMEX dust extraction system is the DEKRA-EXAM-approved alternative to regenerate submicron particulate filters.

The Herding PHARMEX is designed to be resistant to pressure surges so that organic dust with a maximum explosion pressure of 10 bar and a KSt value of 250 bar m/s can be separated without any expensive tertiary explosion protection measures.

The filter housing consists of a welded construction with a smooth surface. At bottom right are the raw gas compartment with Herding sinter-plate filters and the dust discharge hopper to which an assortment of discharge devices can be attached. The clean gas compartment as expansion compartment lies mainly in the left half, with the control unit in the front wall. A submicron particulate filter can be provided as a secondary filter in the lower area of the clean gas compartment.

Benefits:

• Safe system concept with no tertiary measures

• The plant can be installed at any point in the production or engineering area

• Low clean gas concentration < 0.2 mg/m³ after just the first filter stage (depending on the dust)

Specifics:

Design measures make a rupture disk or explosion suppression superfluous.

Contamination is possible when the dust is emptied, but also in the first and second filter stage whenever the filter is occasionally changed. Permissible dust levels at the workplace vary according to the active ingredients contained in the dust. The specific measures required in each individual case can be derived from, for example, the OEL or OEB values, as contained in Guideline M057 issued by BG Chemie (the German trade association for the chemicals industry). In an extended matrix, Herding has assigned suitable solutions in terms of dust disposal and filter change to all potential hazards.

A step in this direction is the sinter-plate filter with service life expectancies of more than 10 years. A central dust disposal system also reduces risk, whereby Herding as a system supplier also offers retroactive conversion as well.

Herding RESIST stands for the round construction of our successful and well-established Herding filter units.

This construction especially suits processes with high demands on pressure and temperature resistance of the filter unit.

They are in use with various products and solid load rates. Products as for example Super Absorbent Polymers, Pigments or Toner are successfully recovered with the sinter plate filter technology.

Filter unit design:

The design of pressure-resistant units corresponds to the pressure equipment directive 2014/68/EU.

Pressure shock resistant units fulfill the ATEX directives 2014/34/EU.

Operating pressures from -1bar up to +11 bar excess pressure and temperatures up to 450°C have already been realized as well as maximum pressure amplitudes of up to 15 bar.

The material of construction of all components can be carbon steel as well as stainless steel, also a combination of both is available. A special surface treatment or e.g. rubber coating of the product effected parts is also available.

Design, production and testing are exclusively realized in our headquarters in Amberg, Germany.

The technical guideline, used by Herding GmbH Filtertechnik, is EN 13445.

Herding Filtertechnik GmbH is certified according to Module A2, Pressure Equipment Directive 2014/68 / EU. Therefore required tests can be carried out and documented on own responsibility.

The filter units can also be used without hopper as bin vent filters or without raw gas housing as silo insert filters. In this way, any kind of arrangement in the customer's  system is possible.

The filter elements are installed from the clean gas side. The element headers are fastened by clamping profiles over the whole length and are also laterally guided by the spacer bushings. This ensures absolute leak tightness and reliability even under extreme high loads. The jet pulse system can be operated with compressed air or inert gas (e.g. N2).

The filter housing has a gas tight design. There are no internal bracings or dead spaces. The gas tightness will be specified individually according to the customer's requirements. The compressed gas reservoir of the jet pulse system is mounted externally. The solenoid  valves are flanged directly on the compressed gas reservoir  and they are available in protection categories IP 65, ATEX- conform, EEx or NEMA/FM approved.

The control voltage can be 24V DC, 24V AC, 230V AC and 120 V AC. As an alternative, pneumatic controlled valves are available.

On demand antistatic filter elements and grounding of all components is available, all flange connections will be equipped with earthing points.

Herding Filtertechnik supplies a variety of programmable filter controller units, they can be adapted on every customer's requirement.

Also operation with a customer's control system is possible.