Abstract: A heat exchanger may be manufactured using a number of different methods, each having their own benefits and deficiencies. A method of making a monolithic heat exchanger having a plurality of conduits passing through it is provided and comprises the steps of: providing a plurality of successive layers of a material to be remelted and energy beam remelting predetermined regions of each layer in accordance with a predetermined design. The energy beam remelting of each layer is performed prior to the addition of a successive layer. The regions of each layer which are subjected to energy beam remelting form solid structures within the layer, and the energy beam remelting of each layer fuses the remelted regions of each layer to the remelted regions of the preceding layer. This results in the manufacture of a three-dimensional monolithic unit. The heat exchanger is manufactured to have a surface area density of at least 5000 m2/m3 and a mean average porosity of at least 0.6.

Abstract: The invention provides a continuous charcoal manufacturing apparatus for turning particulate organic material into charcoal. The apparatus comprises a source of the particulate organic material, a retort and a heating device for heating gas in an external vessel interior space. The source of the particulate organic material comprises an outlet for discharging the particulate organic material from said source! The retort has an external vessel and an inner vessel within the external vessel, whereby the walls of the two vessels are spaced apart from each other so as to define the external vessel interior space between the walls. The external vessel ulterior space is coupled to the source of the particulate organic material so as to allow gases to pass from said space to the source and the inner vessel has an inlet coupled to the source through which the particulate organic material can pass and an outlet for allowing the charcoal to exit the inner vessel.

Abstract: The invention relates to a biochar-containing composition comprising biochar having organic matter therein and/or thereon, clay associated, optionally intercalated, with the organic matter, a non-clay mineral and optionally also a plant growth promoter.

Abstract: A heat exchanger is formed with tessellating conduits 4 passing therethrough. The tessellating conduits having transverse cross-sectional shapes which together substantially completely cover the transverse plane to the heat exchange 2. The tessellating conduits may be the outer conduits 18 within conduit pairs formed of an outer conduit 18 and an inner conduit 22. The outer conduits may have a cross-section that is a regular hexagon and the inner conduits may have a cross-section that is a circle. The heat exchanger can advantageously be formed by selective remelting of material with an energy beam.