In cooperation with several companies different biomass waste such as wood waste, fibre sludge, cocoa shell and panel boards with a high content of phenol-formaldehyde resin have been decomposed by flash pyrolysis into small molecules. The thermal conversion of biomass was performed in a fluidised bed reactor (PDU-scale, throughput 5 kg biomass/h) using the modified and optimised "Hamburg Fluidized Bed Process" ("Hamburger Wirbelschichtverfahren"). The main product was a liquid (bio-oil) with a maximum yield of 50 to 65 wt.%. In addition, pyrolysis gases and solids {charcoal; inorganics) were formed. In many cases pyrolysis of different real biomass waste led to a good yield of bio oil. However, also difficulties with the fluid bed reactor were observed such as large variation in particle size. The oils could be used for production of power and heat, as chemical feedstock or in some cases recycled into the production processes (resin for panel boards).