Patent SE-1830305-A1 (SE)
Title: Device for filtering storm water using plasma technology, nano fiber and airbag system
Inventor: DANNRUP NIELS
IPC: E03F5/04
Filed: 2018-10-23
Abstract: Summary of the inventionlt is an object of the present invention to provide an improvement of the above techniques and prior art. A particular object is to provide device for filtering storm water inside a storm drain. Thisand other objects as well as advantages that will be apparent from the followingdescription of the present invention are achieved by a device for filtering storm waterinside a storm drain according to the independent claim. Preferred embodiments aredefined in the dependent claims. Hence a device for filtering storm water inside a storm drain is provided, wherein thedevice comprises a filter unit, a metal capturing ballast unit, and a floating carrier forcarrying the filter unit and the metal capturing ballast unit, whereby, in use, the device isarranged in a floating condition in the storm water of the storm drain, the filter unit is atleast partially arranged above a surface of the storm water, and the metal capturing ballastunit is arranged below the surface of the storm water, wherein the metal capturing ballastunit comprises a solid material for capturing metal and providing ballast. By means of the present invention it is possible to provide an improved device for filteringstorm water inside a storm drain by providing a metal capturing ballast unit in the device.The use of a metal capturing ballast unit brings about that the device experiences anincreased stability as the ballast unit counteracts any tilting momentum exerted to thedevice from e.g. large flows of storm water reaching the device during heavy rainfall orfrom objects impinging on or building up on the device. Moreover, the use of a metalcapturing ballast brings about that the storm water present in the storm drain will contactthe metal capturing ballast when the device is floating in the storm drain. This brings aboutthat metals present in the storm water of the storm drain may come into contact with themetal capturing ballast and hence be captured, resulting in that the metal is removed fromthe storm water of the storm drain. Hence, the present invention is based on the realisation that the use of a metal capturingballast unit may improve the stability of the device and at the same time remove metalform the storm water in which the device is floating during use. The solid material of the metal capturing ballast unit may comprise slag from production ofraw iron by means of a blast furnace. The use of slag from production of raw iron bringsabout that an efficient metal capturing is provided and at the same time ballasting of thedevice is provided. Moreover, the use of slag implies that the availability of the material isgood and the price is favourable. The solid material of the metal capturing ballast unit may be produced by cooling the slagby means of fresh water, which is advantageous in that a porous material having anincreased contact surface may be provided, resulting in that the efficiency of capturingmetal is improved. The solid material of the metal capturing ballast unit may be a solid granular material,which is advantageous in that the handling of the material is simplified as the material mayeasily be loaded in the device. The solid material may be mixed with nano/micro-fibres and plasma treated stainless steelmesh having more powerful and selective metal capture properties compare to actualmetal removal technologies. Nano/micro-fibres extremely high metal capture speed,selectivity, capacity and a decreased regeneration demand frequency which, is to a greatextent, a function of their extremely large surface areas. Filter unit of the device maycomprise a material selected from the group consisting of porous polypropylene, nano/micro-fibres, plasma treated stainless steel mesh and slag from production of raw iron, andactivated carbon, which is advantageous in that an efficient filter unit may be provided.The metal capturing ballast unit's of the device may further comprise activated carbon,which is advantageous in that further pollutants or contaminants may be removed from thestorm water of the storm drain. The metal being captured may be selected from the group consisting of atomic metal, ionicmetal, or compounds comprising metal, which is advantageous in that metal may becaptured in various forms. The metal being captured may be a heavy metal, which is advantageous in that toxicmetals may be captured. The device may further comprise a sheet of porous polypropylene or nano/micro-fibresand plasma treated stainless steel mesh extending radially outside the device and being atleast partially arranged at the surface of the storm water, which is advantageous in thatpollutants and contaminants, such as oil, present on at the surface of the storm water inthe storm drain may be removed or captured. The device may further comprise a compartment arranged below the surface of the stormwater, wherein the compartment may be provided with porous polypropylene, nano/micro-fibres, plasma treated stainless steel mesh which is advantageous in that further pollutantsor contaminants may be captured or removed from the storm water of the storm drain. As indicated above, the solid material of the metal capturing ballast unit may comprise slagfrom production of raw iron by means of a blast furnace. The filter device eerepršeee e natural materiel es weecl, eetten, bet eeešd else be stainlesseteel mesh ler euppertleg eeid eynthetšc few frlctlen surface leyer The airbag system consists of a flexible fabric envelope, designed to inflate rapidly at sucha situation when the flow of impurities on to a stormwater dwell reaches a critical level tobe set through sensor driven calculation of impurities. lt's purpose is that the cushion(ballon) during a situation where the flow of impurities flow in to the storm drains ( catchbasin ) and the impurities rices above a calculated level, the air bag (ballon) will provideprotection, that the flow of impurities will not reach further on into the stormwater pipelinesystem and reach open water. The stormwater filter air bag "ballon" system is an inflatablecushion designed to protect the storm drain from impurities to flow further on in to the pipesystem and reach open water. The Stormwater filter air bag ”ballon” system is part of aninflatable restraint system, Atypical air bag system consists of an air bag module(containing an inflator or gas generator and an air bag), sensor system indicating the flowand impurities. The sensor system will send out a signal and the Stormwater filter air bag”ballon” system hold a reserve charge after the ignition has been turned off. The backuppower supply lasts between one second and ten minutes. The sensors are designed to prevent the air bag from inflating unless the flow of impuritiesflow in to the storm drain and the impurities rices above a calculated level. The inflator fitsinto the bottom part of the Stormwater filter as a Stormwater filter air bag "ballon" moduleconsisting of a woven nylon bag and a break-away plastic horn pad cover. ln a situation where the flow of impurities flow in to the storm drain and the impurities ricesabove a calculated level, the sensors located in the airbag module will send an electricalsignal activating an initiator. Like a light bulb, an initiator contains a thin wire that heats upand penetrates the propellant chamber. This causes the solid chemical propellant,principally sodium azide, sealed inside the inflator to undergo a rapid chemical reaction(commonly referred to as a pyrotechnic chain). This controlled reaction produces harmlessnitrogen gas that fills the air bag. During deployment the expanding nitrogen gasundergoes a process that reduces the temperature and removes most of the combustionresidue or ash. The expanding nitrogen gas inflates the nylon bag in less than one-twentieth (1/20) of a second, splitting open its plastic module cover and inflating in thestormwater dwell and stopping the flow in to the stormwater dwell and further on in to thestormwater pipes.