Microtherm® in Fuel Cells

2011
Japan -

High Temperature Insulation

Japan

As a commercially viable “sustainable green energy source”, there is increasing global use of fuel cells at all levels of energy production including mains grid supply. Fuel cells can operate virtually continuously as long as the necessary fl ows are maintained. They are one of the cleanest energy sources available, using hydrogen (producible from renewable sources) as the fuel and releasing only water vapour as waste.

Microtherm® high temperature insulation products provide compact insulation protection at continuous exposure temperatures up to 1000°C. Because of this,Microtherm® is the best-selling insulation worldwide for use in hot fuel cells.

A fuel cell system can include the cell itself, a reformer to produce the operating hydrogen and the balance of plant (B.O.P)for all the associated pumps and other equipment necessary to maintain the process fl ows.

Solid Oxide Fuel Cells (SOFCs) operate at 800°C+, Molten Carbonate Fuel Cells (MCFCs) operate at around 600°C, while fuel reformers need 800°C to work efficiently.

Solid or slatted panels are often used for larger FC units whereas machined components may be more suitable for smaller units such as those used for APUs.

As silica is perceived as a contaminant material in some stack designs, Microtherm® Super A is an alternative insulation based on alumina. It has the additional advantage of an upper working limit of 1200°C.

Reformers are also often insulated with Microtherm® Quilted Panel. Proton Exchange Membrane Fuel Cells (PEMFCs) operate at temperatures of only 100°C or less and are much smaller units, making them suitable for road transport and domestic appliances. Diffi cult shapes in small reformers can be insulated with Microtherm® FreeFlow.

This microporous granular product is simply poured into place and the whole process can be automated for volume production. This product is used widely in Japan.

The balance of plant (B.O.P) equipment has a critical effect on overall unit efficiency. Piping systems are insulated with either Microtherm® Moulded Pipe Sections or Microtherm® Flexible Panel.

Microtherm® offers many benefi ts to fuel cell designers. It has the lowest thermal conductivity of all commercially available insulations and ensures the thinnest and lightest insulation system for the most compact product designs. Alternatively, it can provide the biggest internal capacity within a given outer dimension while maintaining thermal performance. It is also the best solution for optimising operational efficiency by keeping energy losses to an absolute minimum.

Microtherm® is clean to use and will not suffer any dimensional or other degradation during prolonged use.

PRODUCTS

Microtherm® Moulded Pipe Section
Microtherm® Free Flow