LAUDA Puridest PD 4 D Double-Distillation Unit, 4 L/h, Conductivity 1.6 µS/cm, L003021

For applications where a simple single-stage distillate is not pure enough, such as in the preparation of cell or tissue cultures, the Puridest PD 4 D distils the water in two stages. The bi-distillation unit reduces the conductivity of the final product from 2.2 µS/cm after the first stage to 1.6 µS/cm after the second stage and delivers up to 4 litres of bi-distillate per hour. The first stage is made of stainless steel, whilst the second stage is made of Duran borosilicate glass 3.3.

Two distillation stages for lower conductivity

In the PD 4 D, the first distillation stage is followed by a second distillation stage, which further reduces the conductivity. A main switch with indicator lights shows the status of both stages. The mono-distillate can be collected separately via a borosilicate glass stopcock fitted with a PTFE plug; the finished bi-distillate drains freely through a borosilicate glass dust-proof bell, no storage tank is provided for this purpose. An electronic contamination monitoring system for the distillation flask stops the distillation if necessary and displays a visual cleaning prompt; an electronic level monitoring system operates throughout the entire process.

Material combination and safety

The tubular heating elements and the first-stage distillation flask are made of stainless steel; the second-stage condenser is made of Duran borosilicate glass 3.3, including a splash guard. A dual low-water protection system comprising a float switch and a thermostatic over-temperature protection switch provides additional safety for the unit. The double-walled housing, made of galvanised, powder-coated sheet steel, accommodates the connections for three-phase power and cooling water: 400 volts, 3/N/PE at 50 or 60 hertz, 2 litres of cooling water per minute at a pressure differential of at least 3 and at most 7 bar.

Typical applications

• Bacteriological and medical sample preparation
• Preparation of cell and tissue cultures with high purity requirements
• Cleaning and sterilisation processes in the laboratory
• Preparation of buffer solutions in quality assurance, development and research

Series overview

The bi-distillation units in the Puridest range comprise the PD 4 D, the PD 4 DG and the PD 8 D, with capacities ranging from 4 to 8 litres per hour. For those who, within the same performance class, prefer both stages to be made of glass rather than a combination of stainless steel and glass, this is available in the Puridest PD 4 DG. For a higher throughput at the same conductivity, the Puridest PD 8 D is available with a capacity of 8 litres per hour. If a simple single-stage distillate is sufficient, the Puridest PD 4 G covers the same performance class without a second distillation stage, whilst the Puridest PD 4 R offers the same single-stage performance in a stainless steel version.

Technical details

Scope of delivery

• LAUDA Puridest PD 4 D, base unit (order number L003021)
• Mains cable with CEE plug (IEC 60309, 5-pin, 16 A)

Accessories required for operation, such as connection hoses for the cooling water supply or collection vessels for the bi-distillate, are not included in the Scope of delivery.

Regulatory information

This unit is an electrical appliance within the meaning of the German Electrical and Electronic Equipment Act (ElektroG). The WEEE registration number of the manufacturer, LAUDA DR. R. WOBSER GMBH & CO. KG, is DE 66424057. Information on the return of old appliances can be found on our Environment and Disposal page.

Warranty and procurement service

LAUDA provides a standard 12-month manufacturer’s warranty on this device from the date of purchase. Your statutory warranty rights remain unaffected.

As the bi-distillate from the PD 4 D drains freely and does not have its own storage tank, it is worth ordering a suitable collection vessel at the same time. Our procurement service can, on request, compile a list of suitable accessories and spare parts for the Puridest series and also advise on whether, in a specific case, the all-glass PD 4 DG or the PD 4 G mono model is the more suitable option.