A diaphragm pump for fluidizing, pressurizing, and conveying products in the form of dust, such as coal dust, using inert gas having pressures of up to 7 MPa has a porous, arched aluminum loosening element and optionally a dual diaphragm. The diaphragm pump ensures that fluidizing gas is supplied and distributed uniformly in the dust pump lower region, and the contour of the dust chamber may be adapted to the deflection of the diaphragm and possibly to the guide rod of the diaphragm. Uniform and reversible deformation of the diaphragm with as little wear as possible is thereby achieved. After the discharge operation of the diaphragm pump has ended, largely planar contact of the diaphragm on the arched, half-shell-shaped loosening surface and a small dead volume can be achieved, leading to a minimal dust chamber volume together with a high delivery rate and a small high-pressure gas loss.