Paper industry treatment of wood and road in the process

The bark step produces a residual product called bark press filtrate. This is very acidic and therefore corrosive but also abrasive. Here we are happy to offer a displacement pump, in the form of hose pump, membrane pump or a piston diaphragm pump.

The chips go on a conveyor to a screening house, where the chips are sorted/grated. From the screening house, the chips are blown to the coking plant. This transport is very labour intensive and therefore ceramic hoses and ceramic tubesespecially bends, good to use.

After boiling, white liquor is added to boil out the lignin. White liquor/Sodium liquor (NaOH) has a high low pH and plastics are normally not an option.

If the goal is a white mass, a bleaching step follows the boiling process. Different oxygen steps are used here, hydrogen peroxide and chlorine dioxide. Hydrogen peroxide and chlorine dioxide are corrosive and we therefore have a wide range of products that can handle this. Above all, we have good linear control valves, on/off valves. For particle-free media, we can use magnetic drive pumps.

The chlorine dioxide that may be used is produced from chlorates that are coated with a lot of particles. Here we can offer in particular a ceramic pump to pump this flow. Chlorine dioxide is usually produced at the mills in a separate process at the mill.

If hydrogen peroxide is used in the process, it should be circulated to prevent it from decomposing and reverting to hydrogen. Here we use acid-resistant centrifugal pumps.

The paper pulp is then pumped on to the paper web and then the pH may need to be lowered and then, for example, sulphuric acid (H2SO4) is used for the adjustment. Here is needed pumping, plastic tubes, plastic valves and tanks. Now a dewatering process of the mass begins.

When treating the paper, different media are used to coat the pulp. For example, for the coating adhesive, we can use a linear diaphragm pump. Depending on what is to be produced, different coating materials are used with varying needs, but often more highly viscous substances are used. Therefore, again, there are different forms of displacement pumps that are relevant.

Process water in the mill

Usually we take fresh water from a lake or river which is used for much of the process. The sand trap takes the coarser particles and humus, and in water treatment we want to remove the living organisms and therefore add hydrochloric acid (HCl). Here we offer pipes, tanks and valves.

Coke oven

When using pine in the process, you want to split the soap from the wood, this is done in the pine oil boiler. Sulphuric acid is used in this process. This process is very hot and lined steel products such as valves and pipes are very useful here. The residual acid is up to 100 degrees hot. Static mixer can be used for the mixing of H2SO4.

Black liquor and soda pan

To convert the residues from the coking plant into white liquor again, we need to make the black liquor, which is the used liquor, in a combustion process. This takes place in the soda boiler. The result is the white liquor that goes back into the process. In the soda boiler process we use lime and milk of lime and therefore we use ceramic hoses, tube and centrifugal pumps.