SOLVENT RECOVERY UNITS

Donau Carbon Technologies SRL realizes solvent recovery plants with activated carbon adsorption in most different industrial sectors, employing, according to any process peculiarity, regeneration with steam, nitrogen or nitrogen plus vacuum.
A distillation section, batch or multicolumn, working in pressure or vacuum, equipped with double effect heat recovery systems, and, in case, a dehydration section with molecular sieves usually completes the plant.

CARBON ADSORPTION & NITROGEN or NITROGEN PLUS VACUUM REGENERATION UNITS (SRN)

This process is employed in presence of water soluble solvent (e.g. Ethyl Acetate, Alcohol, MEK) and mainly in flexible packaging, petrochemical, pharmaceutical industries.

The solvent laden air is sucked from production by means of a fan, and after filtering and cooling, is sent to the adsoption section composed by adsorbers connected in parallel or in series.

When the carbon is saturated the regeneration with nitrogen takes place through the following steps:

Oxygen elimination from the adsorber by fluxing with nitrogen
Activated carbon heating with nitrogen in closed circuit and condensation of solvent released by carbon
Activated carbon cooling for the new adsorption phase
The raw solvent recovered is purified by means of distillation and/or dehydration.

R&D department developed in 2018 a new regeneration method with nitrogen combined with vacuum extraction.

European Patent Office released a Unitary Patent for the Method of carbon regeneration.

Reduction of Energy Consumption
Reduction of Utilities Consumption
Heat Recovery
Carbon Free solutions

CARBON ADSORPTION & STEAM REGENERATION UNITS (SRS)

This process is employed in presence of water low soluble solvents (e.g. Toluene, Hexane) and mainly in rotogravure printing, adhesive tapes, rubber production, extrusion and coating industries.
The solvent laden air is sucked from production by means of a fan, and after filtering and cooling, is sent to the adsoption section composed by adsorbers connected in parallel or in series.
When the carbon is saturated, the regeneration with steam takes place.
Hereafter mixture of water and solvent vapors produced is condensed and cooled.
The solvents not soluble in water (like toluene, hexane, chlorinated hydrocarbon) are separated from water by means of a decanter, while the organic fraction dissolved in water is removed through stripping with air or steam.
For further depuration of solvent, a distillation section can be installed.
The regenerated carbon is cooled and dried with air in closed circuit (Donau Carbon/Lurgi Aktivkhole patent).

WATER ADSORPTION UNITS (SRW)

This process uses water to recover high-boiling, totally soluble, solvents (e.g. DMF).

Mainly it is employed in the synthetic leather, textile and elastic fabrics, on polyurethane basis, production fields.
A water solution is fed at the top of a washing column, which inside is equipped with plates and/or with packing structured in counter flow with the solvent laden air stream.
Water solution with solvent is recovered on the column bottom and, after concentration, check up is fed to a storage tank to be distilled in the same factory or in other plants.
As already said for the solvent recovery plants with activated carbon, Donau Carbon Technologies SRL can supply both the recovery system and the distillery.

XCSR Flexible Compact Solvent Recovery

The modular design of DCT's innovative plant, X-CSR, allows to satisfy the recovery needs of both small and big printing realities.

Strength points of XCSR solution are:

Circular economy
Reduction of raw material
Environmental friendly
CO2 emission savings
Suitable also for small printing industries ~300 tons/y of solvents
Payback time < 2-3 years
Compact, easy maintenance, plug & play design
High residual value
BAT compliant

CSR Compact Solvent Recovery

Due to our yearlong experience we developed, besides “standard” solvent recovery plants, also solutions on skid in compact and modular type

The picture shows a closed realisation, with curtain claddings, container style. The civil works are reduced to a platform. In case of need, it can be easily moved away and transferred to other locations. The erection times are minimal, because the plant is supplied fully preassembled.

MSR Modular Solvent Recovery

For big size plants, the recovery plant is modular! Assembly of prefixed modules, fully filled up in factory, composed to comply with the different layout, recovery capacity, quality and solvent charge.

For further information please contact us!