Pressurised container, system and method for removing impurities from a biogas assembly

摘要

Vacuum container (10) for connecting on a biogas plant, which generates biogas via anaerobic digestion of a biomass, comprises: an inlet (3) for connecting to a suction line extending into the biogas plant, and for filling the vacuum container with a mixture containing impurities including sand, and a system liquid, preferably water; a first outlet for discharging impurities; a second outlet for discharging the system liquid and connecting to a recirculation line in the biogas plant; and a ventilation opening through which a vacuum is generated in the vacuum container. Independent claims are also included for: (1) a system for removing impurities from the biogas plant, comprising the vacuum container with the outlet for discharging the mixture containing impurities and the system liquid, preferably water, and a device following the outlet for separating water insoluble solid components of the mixture and the liquid, where the separating device is a glass screw, and/or comprises a discharge with a discharging valve, through which the separated liquid is re-circulated along a discharge line into the biogas plant; and (2) operating the biogas plant, comprising (a) connecting the biogas plant to the vacuum container, (b) discharging the mixture from the biogas plant under the influence of a vacuum in the container, and introducing into the container, (c) opening the outlet in the vacuum container to supply back the liquid discharge from the vacuum container, preferably biogas plant, and (d) extending a withdrawal period by at least 10 seconds before performing the step (c), where the impurities of the liquid mixture, preferably system liquid get deposited.