Carbon Fiber Water Grass · Technical Reference & Specifications

Overview

Carbon fiber water grass is a hanging biological carrier: a suspension cord is threaded through tufts of carbon fiber filaments, so the finished strand looks like a long narrow brush. Hundreds of these strands are hung from a rope, a frame or a floating support, and the filaments stay spread out in the water instead of collapsing into a bundle.

In the trade the product is also sold as carbon fiber ecological grass or artificial water grass; the terms describe the same type of carrier. It is used where a biofilm has to be established on a surface that stays in the water for a long time — biological contact oxidation tanks, oxidation ditches, and in-situ treatment of rivers, lakes and other slightly polluted surface water.

Unlike a rigid fixed packing or a loose suspended ball, this carrier is a hanging unit. Nothing has to be built inside the tank to hold it: the strands are anchored above the water and simply hang in the flow, which makes the carrier suitable both for new installations and for retrofitting existing structures.

Structure & How It Works

Filament surface

Each strand exposes a dense, even mass of small-diameter filaments along its whole length. Biomass attaches to the filament surface, and because the filaments are thin and closely set, the strand carries a large attachment area in a small volume of delivered material. The brush form keeps the filaments separated, so the strand does not mat down flat in the water.

Contact with the flow

Hung strands move slightly with the water and air flow. That movement brings the bulk liquid into contact with the biofilm and helps carry away excess biomass, so the film stays active instead of building up until it blocks the waterway. In aerated tanks the filaments also break coarse bubbles into smaller ones as they pass through the strand.

Attachment and growth

Once the carrier is hung in an aerated or flowing tank, biofilm develops on the filament surface and thickens over the first weeks of operation. The strand then works as a submerged fixed-film zone: the water passing through it is treated by the attached biomass, while the suspended biomass in the tank continues to work in the usual way.

Material Notes — Carbon Fiber

Carbon fiber is made by carbonizing a precursor fiber (commonly polyacrylonitrile) at high temperature, so the finished filament is mostly elemental carbon. As a material it is light, strong in tension and chemically inert.

• Chemical stability: carbon fiber resists attack by acids, alkalis and the biological activity in wastewater, and it does not rot in water.
• No leaching: the filament does not dissolve or shed organic material into the treated water, so it adds no BOD or COD load of its own.
• Dimensional stability: the filament does not swell or soften in continuous immersion, so the strand keeps its shape and spacing.
• Conductivity: carbon fiber conducts electricity — a property that distinguishes it from most polymer filaments used for biofilm carriers.
• Mechanical care: carbon fiber is strong in tension but brittle when sharply bent, so the strand must not be kinked or dragged over sharp edges during handling and installation.

These are general properties of carbon fiber as a material. The filament grade and composite form used in this carrier are confirmed against the order.

Key Features

1. Brush-type strand. Filament tufts are fixed along the full length of the suspension cord at close, even spacing, so the strand carries attachment surface over its whole length.
2. Open filament structure. The filaments stay spread in the water rather than compacting, which keeps the carrier in contact with the flowing water.
3. Chemically stable in service. The filament does not rot or degrade in continuous immersion and does not shed organic debris into the tank.
4. Hangs in an existing structure. The strands are suspended from a rope, frame or floating support, so no structural work is needed inside the tank or watercourse.
5. Retrievable. Strands can be lifted out of the water for inspection, cleaning or replacement without emptying the tank.
6. Made to the project. Strand length, spacing and the number of strands per unit are set to the tank depth and the process design, so the carrier fits the volume that has to be filled.

Typical Applications

• In-situ remediation of rivers, canals and lakes with slightly polluted surface water
• Biological contact oxidation tanks and integrated biological units
• Oxidation ditches, aeration tanks and activated sludge plant retrofits
• Municipal sewage treatment plants where attached biomass has to be increased
• Industrial wastewater — dyeing and printing, papermaking, food and beverage, chemical
• Landscape water bodies and aquaculture water where biofilm support is required

Installation, Operation & Maintenance

1. Set the depth and spacing first. Strand length, hanging depth and the distance between strands are fixed by the process design; they are not standard values, so confirm them before the order and before installation.
2. Hang from a sound support. Anchor the suspension rope, frame or floating support so each strand hangs free of the tank floor and clear of mixers, diffusers and pipework. Keep the strands out of direct contact with sharp edges and hot surfaces.
3. Keep the cord under even tension. The filaments must not be forced to carry the weight of the strand; the cord or the frame takes the load.
4. Commission with the tank. Hang the strands before or during the start-up of the biological process so the biofilm develops on clean filaments.
5. Inspect periodically. Check the suspension cord and the anchor points, and look for accumulated debris or damage to the filament tufts. Follow the site's rules for work at height or over water.
6. Clean when fouled. Lift the strands and rinse or wash off excess solids as required by the site's maintenance schedule; do not use sharp tools or aggressive chemicals on the filaments.

Specifications

Item	Value
Product	Carbon Fiber Water Grass (hanging bio-carrier; carbon fiber ecological grass)
Type	Hanging (suspended) biological carrier for biofilm
Filament material	Carbon fiber composite filaments
Support	Suspension cord with filament tufts fixed along its length
Mounting	Hung from a rope, frame or floating support
Strand & unit size	On request — set to the tank depth, water depth and layout
Spacing between strands	On request — confirmed with the process design
Specific surface area	On request
Service life	On request
Export packing	On request — bundle or carton, confirmed per order
MOQ / price	On request — confirm strand size, quantity & destination

Data Status (please read)

No catalogued parameter sheet has been released for this product line, so every value that is not a fixed property of the product — strand length, spacing, specific surface area, service life — is quoted as On request rather than filled in with an assumed figure. Confirmed values are issued per order against the drawing.

To receive a full specification and price, send the tank or watercourse depth, the water quality data (COD, BOD, NH₃-N, SS), the treated volume and the required strand spacing. We will confirm the strand dimensions, the number of strands, the export packing and the price.

Compiled from the material properties of carbon fiber and standard practice for hanging biofilm carriers. It is a reference note, not a guaranteed specification; the confirmed values for a specific order take precedence.