The present invention relates to a method for treatment of a slurry comprising a liquid and particles suspended in the liquid. The method comprising the steps of providing a slurry to be treated; subjecting the slurry to a separating stage in which the particles of the slurry are divided into at least two subsets, a first subset being generally less difficult to dewater than a second subset; feeding a pressure filter with a flow of the first and second subsets, wherein in a first feeding step, a major part of the flow is defined by the first subset and in a subsequent second feeding step, a major part of the flow is defined by the second subset.

A filtration system for a fuel cell hybrid propulsion system includes a first stage filter, a second stage filter positioned downstream of the first stage filter, and a third stage filter positioned downstream of the second stage filter and configured to be positioned upstream of a fuel cell system. The first stage filter has first pores with a first mean pore size. The second stage filter has second pores with a second mean pore size. The third stage filter has third pores with a third mean pore size. The second mean pore size is less than the first mean pore size. The third mean pore size is less than or equal to the second mean pore size. The first, second, and third stage filter are structured to filter an airflow prior to being received by the fuel cell system.

A filtration system for a fuel cell hybrid propulsion system includes a first stage filter, a second stage filter positioned downstream of the first stage filter, and a third stage filter positioned downstream of the second stage filter and configured to be positioned upstream of a fuel cell system. The first stage filter has first pores with a first mean pore size. The second stage filter has second pores with a second mean pore size. The third stage filter has third pores with a third mean pore size. The second mean pore size is less than the first mean pore size. The third mean pore size is less than or equal to the second mean pore size. The first, second, and third stage filter are structured to filter an airflow prior to being received by the fuel cell system.

To provide a highly convenient filter-plate-type filtration device capable of more effectively preventing leakage of a raw liquid to be filtrated and filtrate through a filter material. The filter-plate-type filtration device includes: a plurality of filter plates arranged with a filter material sandwiched therebetween; a filtration chamber formed between the plurality of filter plates; a raw liquid introduction path configured to introduce a raw liquid to be filtrated into the filtration chamber; a pressure sealing unit configured to apply a sealing pressure to the filter material such that leakage of the raw liquid to be filtrated and the filtrate from inside of the filtration chamber to outside of the filtration chamber is prevented; and a control unit configured to automatically control the sealing pressure in response to fluctuations in a pressure in the filtration chamber.

A system includes a non-transitory computer-readable medium having instructions stored thereon. The instructions, when executed by one or more processors, cause the one or more processors to acquire air quality data regarding an air quality of air upcoming, proximate, or entering an air inlet of a filtration assembly, close or restrict the air inlet in response to the air quality data indicating that the air upcoming, proximate, or entering the air inlet is of a quality lower than a quality threshold to substantially prevent dirty ambient air from entering the filtration assembly, and activate air storage to provide an air supply to the filtration assembly when the air inlet is closed or restricted.