Sintered Activated Carbon Block Filter Ф51×127 for Water Purifiers

This is a sintered activated carbon block filter, supplied as a finished cartridge in the Ф51×127 mm format, made by Oltaven from high-iodine-value coconut shell carbon with food-grade ion exchange resin built in. It filters drinking water at the point of use: chlorine and its bleaching-powder taste and odour, colour, organic pollutants such as VOCs, and heavy metals including lead and mercury, while the resin helps soften the water and limit scale. It is made for appliance and water-treatment OEMs and brands that fit CTO or T33-style cartridges into reverse-osmosis purifiers, water dispensers, refrigerator water systems and commercial coffee machines.

From Media to Finished Filter

A carbon block is often described by its raw material, but the powder is only the starting point. What a user experiences at the tap — how fast water flows, how long the taste stays clean, whether fine black particles appear in the glass — is decided by how that powder is formed into a solid cartridge. Oltaven sells the finished filter, not the media, so the forming steps are where the product is actually made.

Sintering binds coconut shell carbon particles together into a rigid, porous block without a loose granular fill. The block holds a uniform microporous structure, so water is forced through the carbon wall rather than channelling around it. That structure gives a high initial flow and a defined filtration rating, and it keeps the carbon from migrating downstream — the reason a well-formed block does not shed black powder into the water.

Pleating and framing, where a pleated design is used, set the surface area that meets the water and the geometry that fits the housing. Sealing and end-cap construction close the block to the housing so water cannot bypass the carbon. Each of these decisions trades off against the others, and the finished cartridge is the balance the application needs.

What Decides Finished Performance

Media choice

High-iodine-value coconut shell carbon offers a large adsorption capacity for chlorine, taste and odour, and organic compounds. Adding food-grade ion exchange resin inside the same cartridge extends the job to softening and heavy-metal reduction, so one cartridge handles taste and scale together. Media grade and the carbon-to-resin ratio shift capacity and service life.

Forming and structure

The sintered block's wall thickness and pore structure set the resistance water meets and the contact time it gets with the carbon. A denser, finer structure can raise filtration precision but also raises pressure drop; a more open structure protects flow but shortens the adsorption path. Because the block is formed as one piece, the microporous structure stays even along its length, which supports a high initial flow and a long service life.

Dimensions and sealing

Outer diameter, inner diameter and length decide how the cartridge seats in its housing, and end-cap welding or sealing closes the flow path. A cartridge that is dimensionally right but poorly sealed lets water slip past the media, and measured efficiency falls even though the carbon is good. Oltaven supports custom end caps and sealing arrangements, so the finished part matches the device rather than being adapted to it.

Applications

• Household reverse-osmosis purifiers: as the pre-carbon CTO stage protecting the membrane, or as the post-carbon T33 stage for final taste polishing.
• Direct-drinking water dispensers: point-of-use taste, odour and chlorine reduction.
• French-door refrigerators: built-in water filter cartridges where a compact block fits the internal housing.
• Commercial coffee machines: water conditioning ahead of brewing, where chlorine and scale affect taste and equipment life.

In each case the same principle applies: the cartridge is selected for the housing it fits and the water it will treat, not for the carbon alone.

Technical Specifications

The Oltaven Factory and Certifications

Oltaven's OEM/ODM capability is the foundation of this product. Over more than 20 years we have developed more than 1,000 filtration solutions for customers, and custom work on this carbon block — dimensions, end caps, media grade, logo and packaging — follows that same development route rather than starting from scratch.

Production runs in a 50,000 m² plant in Zhongshan, Guangdong, China. Six cleanrooms totalling 20,000 m² keep cartridges free of secondary contamination during production and assembly, and automated lines support output of millions of pieces per month.

Quality is controlled through IQC, IPQC and OQC stages, backed by a CNAS-accredited laboratory that can issue reports on filtration efficiency, dust-holding capacity and resistance. The plant holds ISO 9001, ISO 14001 and ISO 45001 certification and gained IATF 16949 in 2024. Products meet REACH and RoHS requirements, with compliance documents available on request.

OEM/ODM Workflow

1. Share the requirement. Send the device model, the housing dimensions or a drawing, the target flow, the water quality and the order quantity.
2. Define the cartridge. We agree on outer and inner diameter, length, media grade and resin content, end-cap structure and packaging.
3. Sample and evaluate. Samples are produced for your bench or field testing before tooling and volume commitments are fixed.
4. Confirm and tool. Specifications, artwork and acceptance criteria are locked, and moulds or end-cap tooling are prepared where needed.
5. Mass production. Cartridges are produced under IQC, IPQC and OQC control, with batch documentation.
6. Ship and support. Orders are packed to your branding and shipped; technical support continues after delivery.

Start a Custom Project

To quote accurately, tell us the device or vehicle model the cartridge fits, the size or a drawing, the required airflow or water flow, the operating conditions (inlet water quality, pressure, temperature) and your estimated quantity. With those details we can propose a specification, sample plan and production schedule. Contact Oltaven to begin.