Patent DE-102008006719-A1 (DE)
Title: Cleaning contaminated materials such as pollutant-contaminated soils from pourable and/or pasty consistency or drying pasty materials and sludge from chamber presses, comprises moving the materials in a closed system into a drying chamber
Inventor: CZETSCH ALEXANDER
IPC: A62D3/40
Filed: 2008-01-30
Abstract: The method comprises moving contaminated materials such as pollutant-contaminated soils from pourable and/or pasty consistency in a closed system into a batch-wise loaded drying chamber (1) lockable in the operation and connected with an assigned condenser unit by a circulating mixer (16a) in a dispensed manner and then heating by a heating device for the purpose of the drainage, and transferring the loaded material pretreated in the drying chamber into a decontamination chamber (2) lockable and connected with the assigned condenser unit (4a) after a predetermined time. The method comprises moving contaminated materials such as pollutant-contaminated soils from pourable and/or pasty consistency in a closed system into a batch-wise loaded drying chamber (1) lockable in the operation and connected with an assigned condenser unit by a circulating mixer (16a) in a dispensed manner and then heating by a heating device for the purpose of the drainage, transferring the loaded material pretreated in the drying chamber into a decontamination chamber (2) lockable and connected with the assigned condenser unit (4a) after a predetermined time and after reaching a determined drying grade under a protective gas atmosphere, and exposing a negative pressure in the decontamination chamber for further heating under circulation and/or for evaporating pollutants and subsequently supplying the material from the decontamination chamber to a discharge over the mixer with a water injector. Nitrogen atmosphere is created in the drying and decontamination chambers and/or in dropping pipes, which connect the drying and decontamination chambers and are provided between the decontamination chamber and the mixer, before transferring the material from the drying chamber into the decontamination chamber. Each dropping pipe connects respective pre-arranged chamber at a controllable bottom flap (28a) and has a separating slider. After filling the drying chamber with nitrogen, the bottom flap arranged to the drying chamber opens and fills the dropping pipe area up to the slider with nitrogen and after filling the decontamination chamber with nitrogen, the slider opens and the material transfer is carried out under the protective gas atmosphere. A hot steam occasionally standing under pressure is injected into the drying chamber on both sides in dependent of the consistency, the type of the pollutant of the materials and/or the dimension of the mixer-torque required for the material circulation. The injection of the hot steam is regulated as a function of the continuously detected driving-torque of the mixer. The hot steam generator is heated with energy from a heat exchanger arranged in the exhaust gas flow of the central heating device for heating the chamber. The waste air of the decontamination chamber is subjected to a high temperature post-combustion process and the post-combusted waste air is subsequently supplied to a burner for heating the chamber. The material discharged from the decontamination chamber is cooled off in the closed mixer by injecting water at earth-moist consistency and the water steam developed in the mixer is cleaned and condensed in a closed system. The material in the mixer is admixed to an auxiliary material for immobilizing and connecting heavy metals. Bacteria is supplied to the material in an area of the closed mixer having a temperature of 30-40[deg] C and intensively intermixed with the material. The two drying chambers are operated together with the decontamination chamber for increasing the capacity and/or with high moisture content of the material to be cleaned in a time-delayed and time-overlapped manner. An independent claim is included for a device for cleaning contaminated materials such as pollutant-contaminated soils from pourable and/or pasty consistency or for drying pasty materials and sludge from chamber presses.