Verfahren zur Verfestigung und Einkapselung von Sonderabfällen zum Zwecke der Ablagerung

Solidification and encapsulation of special wastes for disposal purposes . Apart from problems caused by special wastes due to their generally high content of harmful substances as well as other hazardous properties, difficulties in treatment and disposal of liquids, slurries and sludges are increased by their nonsolid state. Transformation of such special wastes into solid and largely non-reactive products could offer a possibility of avoiding the difficulties at conventional disposal facilities. Solidification processes are also of interest in as much as they might open a way to dispose of such special wastes not only at special-waste disposal facilities but also jointly with residential wastes at ordinary landfills. Recently solidification processes have been developed and are, in part, commercially applied in various countries. Utilisation or landfill disposal of the solidification products demand the definition of certain minimum requirements. Requirements with regard to water pollution prevention (e. g. leachability) are more difficult to formulate than other requirements unrelated to water protection (e. g. strength).     

Thermische Behandlung von Sonderabfällen

Thermal treatment of special wastes . The incineration of waste is a proven process with known ecological consequences and is economically viable especially for large scale plant. The original ambitious objectives of the pyrolytic process have been considerably revised after the developments in this area failed to live up to many expectations or were found to be economically non-viable. The combustion of chlorinated hydrocarbons on the high seas is ecologically safe. The processes discussed in this paper demonstrate that the development of thermal processes for the treatment of industrial wastes is by no means complete. This also applies to numerous other processes not discussed here.     

Pyrolytische Rohstoff-Rückgewinnung aus Sonderabfällen

Pyrolytic recovery of raw materials from special wastes . The pyrolytic techniques developed especially for producing smelting coke from coal and in petroleum refining can be applied to the thermal decomposition of waste materials having a high organic content. Fluidized bed reactors and rotary kilns are particularly suitable as universally applicable pyrolysis units for continuous operation. Highly aromatic pyrolysis oils for use as chemical raw material, heating gases for the autothermic operation of the pyrolysis unit, and carbon and solids containing nonferrous metals are obtained from plastics waste, used tires, old cable, shredder wastes, and acid resins at reactor temperatures of about 700°C. Largescale applicability and economics of the process have yet to be proved.     

Rohstoff-Recycling und Energie-Gewinnung von Kunststoffabfällen

Feedstock Recycling and Energy Recovery from Plastics Waste. The disposal concept of the plastics industry comprises the following four steps: prevention/reduction, recycling of material (mechanical recycling, feedstock recycling), energy recovery and dumping. Feedstock recycling or chemical recycling stands for the chemical conversion of polymer materials with reduction of macromolecular structure to low-molecular raw materials. The combustion of plastics waste uses the high calorific value of plastics for energy recovery. This paper describes some of the processes for feedstock recycling and for energy recovery from plastics waste.     

Beseitigung von Abfällen in einer Sonderabfall-Deponie

Disposal of waste material in hazardous waste-tips . In setting up and operating hazardous waste-tips the greatest of care is necessary, since the public reacts strongly, even to the slightest pollution of the environment in the neighbourhood of such tips. As an example, the waste-tip at Malsch south of Heidelberg is considered from all points of view, beginning with the geological prerequisite, the sealing measurements and control of the tip. The procedures in making applications to authorities, the equipment required and the method of running the tip are also dealt with. Until now, no serious incidents have occurred at the waste-tip at Malsch.     

Zukunftssichere und umweltneutrale Beseitigung von Industrieabfällen

Low environmental-impact disposal of solid, liquid and semisolid industrial residues . In many production plants, waste residues are formed which must be treated before their disposal so as to safeguard against environmental pollution. Industrial methods for the treatment and disposal of residues are so multifarious that each disposal problem requires careful consideration so as to ensure selection of the most suitable method, both from the ecological and economical point of view. Dumping grounds cannot accommodate all waste materials without endangering or disturbing the environment. For incineration, proven methods are available which can be modified to suit the particular waste problem at hand. After a suitable pretreatment every effort must be made to achieve a waste free from organic materials, an optimum utilization of heat and a flue gas purification without inadmissible loading of waste gases and waters. In recent years there has been a considerable increase in research and development activities in the area of thermal treatment of solid, liquid and semi-solid wastes. Worth mentioning are the high-temperature methods giving favourable emission values and methods for degasification and gasification directed at the recovery of important raw materials. Plants based on these principles are currently being operated on the pilot scale.     

Verbrennungsanlage mit Rauchgaswäsche für die Beseitigung von Chemie-Abfällen

Incineration plant with flue-gas scrubbers for disposal of chemical waste . Incineration plant No. II installed at the Bayer Facilities at Leverkusen/Germany has been in regular operation since November 1977 after a previous one-year period of testing. About 25 000 t of industrial waste per year can be burnt in this plant, simultaneously producing nearly 140 000 t of steam. The plant consists of a bunker building, a rotary kiln and secondary combustion chamber, including all the feeding equipment for solid, viscous, and liquid wastes, as well as a boiler, an electrostatic dust precipitator, and a wet gas cleaning unit. This latter unit consists of an injection cooler (quencher), two rotary scrubbers, and a jet scrubber. The cleaned flue gas is reheated in two heat exchangers and is discharged from a suction blower through a 100 m high chimney into the atmosphere. Around the chimney several measuring instruments are installed to check and continuously record the type and amount of emission. The scrubber water is sent to the company waste water treatment plant; the solid ashes and dust are dumped separately. The average incineration costs are DM 400 per ton of waste.     

Maschinentechnik beim Füllen von Anstrichmitteln

Machines for Filling Coating Materials To start with, the aerosol filling technique is reviewed. The filling of colours in aerosols is treated at a greater detail. Further, the requirements which are to be set on filling machines and their constructional materials are given. Finally, the filling systems and future marketing prospects are explained.