Abstract: A method and apparatus for providing bubble-free liquid carbon dioxide to a user is disclosed. For cost-effective supply, gaseous CO2 is removed from a supply line, liquefied in a condenser and transported to the user.

Abstract: A method of and an apparatus for discharging containers of solubilized gas, e.g. acetylene, in which the gas is initially drawn as a preference stream from one container or group of containers (e.g. conventional acetylene bottles or tanks) and is fed to the consumer. When the pressure in the tank or tanks falls below a predetermined set point value, thereby indicating that the volume flow rate is less than the mean or average flow requirement, a second tank or group of tanks is connected to provide a complementary flow. The second tank or group of tanks supply the total requirement during replacement of the first tank or group and then forms the preference stream while the replacement tank or tanks of the first group provides the complementary stream.

Abstract: Low temperature embrittlement of materials which otherwise cannot be readily comminuted is carried out by treating the materials, g.g. scraps of synthetic resin containing components which might otherwise be released into the atmosphere, with a circulated cooling gas to cause the embrittlement of the materials. The latter are then conveyed through a mill, e.g. a pin-type attrition mill, in a carrier gas and are comminuted therein. The cooling gas is passed continuously around a closed circulation path so that any released components remain trapped in the circulated gas which, in turn, is cooled to a sufficiently low temperature by a separately displaced cooling fluid passed in indirect heat exchanging relationship with the cooling gas stream along the closed path of the latter.