Donaldson Membranes Helping The Environment

Donaldson Membranes and filter bag manufacturer Filterteks, have joined forces to provide a filtration solution at paper production plant, Oyka.

Boiler manufacturer, Mimsan Isi Teknolojileri A.S fitted a boiler to the plant to provide steam for power. The steam is created by burning sawdust, a waste bi-product of the paper production process, to generate heat and power, thus eliminating the use of non-renewable fossil fuels and decreasing the impact on the environment.

Donaldson Membranes and Filterteks became involved in the project when the conventional needlefelt being used in the baghouse became scorched and holed due to the presence of burning embers causing excessive particulate emissions to be released into the atmosphere and regular filter isolation for bag replacement.

Filterteks themselves recommended a number of modifications to reduce the oxygen content, such as closing all fresh air inlets and recycling the hot air in the exhaust system to reduce the oxygen level and risk of combustion.

Despite these modifications the second set of conventional PPS filterbags failed in much the same way. Filterteks contacted Donaldson Membranes who suggested using Tetratex® Ultra High Efficiency #6255 Woven Fibreglass this fabric being suitable for continuous service at temperatures of up to 260°C and more resistant to damage from hot sparks than PPS.

Tetratex membrane filter media can be employed in a wide variety of adverse conditions and applications, giving near-zero emissions against fine and aggressive particulate.

The key differentiation that Tetratex ePTFE membrane filter media provides over conventional non-membrane media is its non-reliance on a filter cake. Non-membrane media will often allow the passing of quantities of fine particulate not only into but also beyond the media. This is especially so on start-up when the media is new. Conventional media only truly start to filter efficiently when a suitably dense filter cake has formed on the filter surface. Whilst this can sometimes provide the necessary performance, the reliance on a filter cake and the readiness of fine particles to penetrate into the open surface structure of the media often limits the ability of non-membrane media to perform consistently over extended periods of operation. Additionally, capability to recover from process upsets can be limited.

Tetratex ePTFE media delivers exceptional particulate capture rates and excellent dust cake release providing outstanding durability. Increased filter element life and less frequent cleaning can be achieved due to the extreme anti-adhesive properties of the membrane, providing increased efficiency and reduced costs resulting in increased profitability.

The new Tetratex filterbags at Oyka have been working successfully to date for a number of months with great results and Oyka are very happy with the increased energy production levels and the guidance provided by Donaldson Membranes and Filterteks.

Gürol Aldanmaz, Plant Manager, commented: "The production of the steam has been made more successful since the implementation of the new Tetratex filterbags, we are now able to lower the amount of LPG fuel we use, therefore saving costs to the company and also the environment".

Technical Information:

Type of Filter: Pulse Jet Filter, containing 690 filter bags

Number of chambers: 8

Diameter of Filterbag: 160mm

Length of Filterbag: 3600mm

Total Filter Area: 1242 m2

Fan Volume: 120,000 Am3/hr

Filtration Velocity: 1.61 m/min

Operating Temperature: 165°C