Carbon dioxide for polyurethane foaming is a viable cost-efficient and environmentally friendly alternative in continuous and discontinuous foaming processes. High-pressure supply systems and metering devices developed by Linde in close co-operation with industrial partners are very efficient and fulfil new technological requirements. The choice of the system will depend on the carbon dioxide flow rate and the pressure used in the foaming process.
In addition to environmental aspects, the carbon dioxide technology brings economical advantages of which the main are optimum raw material consumption and reduction of foam scrap. Besides that, the low density foams produced with carbon dioxide as a blowing agent, possess very good quality and a homogenous cellular structure.
DSD 500 inert gas metering device
In physical foaming of polymers, i.e. extrusion, injection moulding or polyurethane foaming, the use of inert gases such as carbon dioxide or nitrogen as blowing agents is becoming more common. The reason is that inert gases are an efficient, unexpensive alternative to conventional foaming agents because of their high foaming capacity and low consumption. Moreover, inert gases are eco-friendly, non-toxic, and non-flammable, meeting strict environmental laws.
The patented Linde DSD 500 is designed to meter liquid carbon dioxide, but can also be used for gaseous nitrogen. It consists mainly of one or two high-performance compressors adapted to the use of carbon dioxide, a suitable mass-flow meter, and a special control valve (3/3-way proportional). The DSD 500 is easy to install, without having to precool the carbon dioxide, and allows an extremely accurate gas flow control: independent of pressure, temperature or type of gas. It is suitable for continuous as well as discontinuous operation.
Liquid carbon dioxide pump systems
We can offer a wide range of efficient, low-pressure pumping systems for liquid carbon dioxide in your foaming processes. These systems with up to 80 bar can be used to supply any kind of metering pumps with bubble-free liquid carbon dioxide. The carbon dioxide pressure can be regulated according to your demand.