Pilot plant

Citation

(2002), "Pilot plant", Pigment & Resin Technology, Vol. 31 No. 1. https://doi.org/10.1108/prt.2002.12931aad.001

Pilot plant

Pilot plant

Keywords: Rajamäki, Plant and machinery, Drying

Outsourcing selected stages of development and processing can often provide the key to launching a product which would otherwise be delayed by lack of expert time or specialist resources. The 500 ²pilot plant of the Materials Technology Unit of VTT Chemical Technology, (part of The Technical Research Centre of Finland) in Rajamäki now provides research, process development and optimisation, pilot production and scale-up services for many industries from polymers and specially chemicals to foodstuffs, paper chemicals, coatings and pharmaceuticals.

For synthesis, polymerisation and product modification, Rajamäki has 8 reactors with capacities from 1.5±1 to 1800±1, using either thermo-oil or steam-water heating systems, at temperatures from 50°C to +320°C and pressures from 10mbar to 250mbar. Typical processes include esterfication, etherfication, hydroxyl alkylation, condensation and radical polymerisation, and oxidation as well as chemical and enzymatic hydrolysis. The VTT Materials Technology team has special expertise in biomass fractionation and the modification of natural polymers like starch and other polysaccharides (Plate 1).

Plate 1 Pilot plant of materials technology unit of VTT chemical technology

Separation equipment at Rajamäki includes an Alfa-Laval decanter centrifuge, a Larox rotary vacuum filter, a Westfalia separator and a GFT pervaporator, which together offer a wide choice of separation, purification and drying technologies for efficient product recovery, as well as the facility to handle flammable solvents safely.

Conventional and vacuum distillation can be carried out by the multipurpose reactors. However, for small-scale distillations there is a vacuum fractional distillation unit with packed columns and an adjustable reflux ratio.

Evaporation can also be performed using VTT's Ex-classified failing film evaporator or vacuum contact dryers. The failing film evaporator, particularly suitable for concentrating heat-sensitive products, has a capacity of 30l/h–300l/h over a temperature range of 40°C - 90°C.

The importance of drying processes as the final step in a complex process should not be underestimated because they have a significant effect on the quality and characteristics of the final product. The choice of drying method may be made according to the specific properties of the processed product and the qualities required in the final product. In the chemical, food and pharmaceutical industries in particular, further processing and material handling operations rnay also impose strict demands on the drying process.

At Rajamäki, the choice of product drying equipment includes fixed-bed dryers, spray dryers, and vacuum contact dryers as well as oven and freeze dryers. The Niro spray dryer, for example, uses atmospheric air for the rapid continuous conversion of liquids, suspensions or particle scurries into powders. It has a capacity of 30kg/h–50kg/h, depending on the temperature (typically 70°C to 100°C) and the solids content of the feed material.

The Drais TurboDry contact dryer is used in addition to drying for reactions, evaporations, compacting and granulation, mixing, dispergation and coating. Drying time is short and at low temperature which makes it particularly suitable for drying heat-sensitive materials. The TurboDry also handles product phase-change from Oasty to crumbly consistency without problems. Larger agglomerates can be broken up with a fast rotating homogenizer.

VTT's Rajamäki plant, some 40km from Helsinki's Vantaa Airport, is part of a large industrial site where all utilities including waste water treatment facilities are continuously available.

Details available from: VTT Chemical Technology – Materials Technology, Tel: +358 9 133 1413; Fax: +358 9 133 1395; Website: www.vtt.fi