Abstract: In a process for the treatment of water with ozone a partial current of treated water is contacted under pressure in a packed column with an oxygen-ozone mixture from an ozonizer to oxidize water contaminants and to improve their flocculation. The portion of oxygen which has not dissolved in the water in the packed column is recycled into the ozonizer and the treated partial water current is mixed again with water to be treated. The pressure in the column is adjusted in dependence on the nitrogen content of the water to be treated. By this measure is ensured that the quantity of nitrogen escaping from the water and contained in the cycle oxygen permits an optimum operation of the ozonizer. The nitrogen content in the cycle oxygen is preferably kept below 10% by volume.

Abstract: The ozone content of ozone-containing gas mixtures is determined in a process wherein the ozone is converted to oxygen and which includes channeling a gas mixture containing nitrogen oxides and possibly water vapor through an adsorbent of aluminosilicate which contains 2 to 20% by weight of aluminum oxide and the aluminosilicate is of spherical shape with a particle diameter of 2 to 5 mm and a specific area of 200 to 650 m.sup.2 /g and an average pore diameter of 5 to 10 nm.

Abstract: The device for introducing a gas into a liquid by supplying gas to a gas introducing means located on the bottom of a tank in which the liquid is being held, and collecting the gas above the liquid after it passes through the liquid. A closure for the tank acts to collect the gaseous substances which pass upwardly out of the liquid by adjusting the volume of enclosed space above the liquid level. A means is also provided for removing at least some of the gaseous substances which have accumulated in the enclosed space above the liquid and reintroducing them into the supply being introduced into the liquid at the bottom of the tank.

Abstract: A fluidized bed furnace, particularly for burning partly dehydrated sludge, comprises a furnace housing which has a bottom for supporting a fluidized bed and it includes a plurality of nozzles directed to discharge upwardly through the bottom wall into the bed for supplying heating gases including combustion air. The furnace has side walls which extend upwardly from the bottom above the bed and define a combustion chamber above the bed. The combustion chamber is closed at its top by a substantially horizontal furnace roof. At least one sludge charging opening is provided in the furnace roof for charging the sludge downwardly into the combustion chamber. A post combustion chamber is connected downwardly through the roof to the combustion chamber and it is made of a cross-section which is substantially smaller than the combustion chamber. Means are provided for supplying secondary combustion air to the post combustion chamber.

Abstract: A fluidized bed-furnace for burning partly dehydrated sludge comprises a furnace housing having a bottom forming a surface for a fluidized bed. Side walls extend upwardly from the bottom and above the fluidized bed in defining combustion chamber above the bed. An inlet for sludge on one side of the housing extends into the side walls and a discharge for the sludge on the opposite side of the housing extends outwardly from the side walls. The bottom is made of a plurality of steps arranged at distinct elevations in descending order from the inlet to the outlet or discharge. Each step portion includes a grate having a wind box associated therewith through which heating gases and including combustion air is directed upwardly through nozzle elements which extend in openings of the grate. The entire bottom with all of the step portions are advantageously supported on a support structure which is suspended at the bottom of the furnace and it is advantageously removable from the bottom.