Classifications

• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F9/00—Multistage treatment of water, waste water or sewage
  • C02F9/20—Portable or detachable small-scale multistage treatment devices, e.g. point of use or laboratory water purification systems

Definitions

• the invention relates to a filter for the retention of bacterial contamination and to a plant and method for treating wastewater comprising such a filter.
• a filter is proposed for purifying water of the type comprising:
• filtration means interposed between the inlet and the outlet, characterized in that the filtration means comprise
• distribution means associated with the distribution pipe network and intended to ensure the diffusion of the water to be treated to the filtering means.
• an all-water septic tank comprising an enclosure, a conduit for supplying waste water, a conduit for discharging clear water to a spreading system, decantation means.
• decantation means by depositing on the bottom of the enclosure the heaviest materials and by accumulation on the surface S of fats and light particles and liquefaction at less of these materials by anaerobic fermentation, means of protection of the spreading system to prevent clogging, integrated into the enclosure characterized by the fact that the means of decantation, liquefaction and protection are placed in a single compartment the enclosure;
• the supply duct forms an elbow, the downstream section of which is directed towards an inlet end wall of the enclosure and the outlet of which is open upwards; it comprises a first deflector placed transversely in the enclosure, at least substantially at the outlet, inclined on the vertical;
• the exhaust duct is associated with a vertical partition located partly above, partly below the free surface S at least substantially perpendicular to the lower edge of a second deflector comprising a lower inclined section
• standard P16-603 reference DTU 64.1 dated December 1992, published and distributed by the French Association for Standardization (AFNOR), entitled “Implementation of autonomous sanitation devices” specifies the rules for implementation work relating to autonomous sanitation works such as those for treating domestic wastewater in residential houses with one to ten main rooms.
• the provisions of this standard concerning the treatment channels consisting of an anaerobic pre-treatment system (all water tank) and a reconstituted in-ground spreading system or a sand filtration system.
• Said standard teaches, in particular, that the sand filters comprise a silica sand washed and stable in water having a particle size curve which fits into a certain particle size zone shown in FIG. 9.
• Said standard also teaches that sand filters must have a minimum dimension of the order of 5 m 2 / equivalent inhabitant.
• the invention aims to remedy these drawbacks.
• the invention relates to a filter for the retention of bacterial contamination of effluents, the filtration means of which comprise:
• distribution means associated with the distribution pipe network and intended to ensure the diffusion of the water to be treated to the filtering means.
• the filter is dimensioned between 0.2 and 0.9 m 2 / equivalent inhabitant.
• the network of distribution pipes is adjacent to a first surface of the granular filtering layer, in particular placed outside.
• the network of drainage pipes is adjacent to a second surface of the granular filtering layer, in particular placed in a draining layer located below the granular filtering layer, the filtering layer and the draining layer being separated by a weight geotextile of approximately 100 g. / m.
• the filter further comprises a protective layer in which the network of distribution pipes is located and which is adjacent to the granular filtering layer.
• the network of distribution pipes comprises at least one ply of several pipes spaced transversely with respect to each other and in communication with each other, particularly in the vicinity of the entrance.
• the perforations in the distribution pipe network are arranged substantially perpendicular to the thickness of the granular filter layer.
• the distribution pipes are provided with overflow holes distributed longitudinally, opposite the first surface of the granular filtering layer.
• the distribution pipes are respectively covered with a means of protection - such as an inverted gutter - intended to avoid obstruction of the perforations and / or overflow orifices without preventing the distribution of the effluents.
• a means of protection - such as an inverted gutter - intended to avoid obstruction of the perforations and / or overflow orifices without preventing the distribution of the effluents.
• the distribution means are in the form of an effluent absorption and diffusion ply interposed between the network of distribution pipes and the filtering means.
• the distribution means are in the form of water absorption and diffusion bands interposed between the network of distribution pipes and the filtering means. These bands appear in the direction of flow in the form of a draining layer and a fine filtering layer.
• the distribution pipes are placed in the middle part of said strips.
• the network of drainage pipes comprises at least one ply of several pipes spaced transversely with respect to each other and in communication with each other, particularly in the vicinity of the outlet of the filter.
• the filter also comprises an external casing in which the two networks of distribution and drainage pipes are housed, the filter means interposed between the two networks and the distribution means associated with the distribution network, this casing having an inlet and an outlet.
• the casing has a U-shape, in particular the opening of which is closed.
• Such a filter may further comprise a device for sequential injection of the effluent such as an electric pump, a tilting trough or a siphon which can be primed by a pressure bell.
• a device for sequential injection of the effluent such as an electric pump, a tilting trough or a siphon which can be primed by a pressure bell.
• the invention relates to a domestic wastewater treatment installation comprising from upstream to downstream:
• a first filter comprising filtering means in the form of at least one granular filtering layer with a porosity of between 0.2 and 5 mm approximately, capable of ensuring the retention of a substantial part of the organic materials of the effluents;
• the first and second filters have a similar or analogous general structure.
• the first filter is sized between 0.2 and 0.9 m 2 / inhabitant equivalent.
• the all-water septic tank is sized between 0.2 and 1 m / equivalent per inhabitant.
• the septic tank includes an enclosure, a conduit for supplying waste water, a conduit for discharging clear water to the first filter and decantation means.
• the decantation, liquefaction and protection means are placed in a single compartment of the enclosure.
• the supply duct forms a bend, the downstream section of which is directed towards the inlet end wall of the enclosure and the outlet of which is open upwards.
• the septic tank comprises a first deflector placed transversely in the enclosure, at least substantially at the outlet, extending over all or at least a substantial part of the width of the enclosure, inclined in particular from 35 to 45 degrees over the vertical from the bottom to the cover and from the inlet end walls to the outlet end walls, the first deflector having the function of improving the settling and limiting the progression of turbulence towards the bottom of the enclosure .
• the exhaust duct is associated on the one hand with a vertical partition situated partly above, partly below the free surface at least substantially perpendicular to the lower edge of the second deflector which comprises a lower inclined section of the bottom towards the cover and from the inlet end walls to the outlet end walls.
• the vertical partition, the second deflector and side partitions define a passage for clear water comprising an at least substantially vertical inlet opening, a bend and an outlet opening in communication with the discharge conduit.
• the upstream section of the septic tank supply duct is located at a level higher than that of the evacuation duct.
• the enclosure of the septic tank comprises two parts which are identical or substantially similar to one another: a lower shell and an upper shell, each of them having a trapezoidal cross-section and longitudinal cross section, the two shells being connected l to each other by their large common base.
• the supply duct, the exhaust duct as well as the vertical partition and the second deflector are entirely located in the upper shell which has on its cover two manholes while the first deflector is located at least partially in the shell upper and near the base.
• the first deflector, the second deflector and the vertical partition are of a space allowing their passage by a look.
• the lower edge of the first deflector determines the upper admissible level for the sludge accumulated on the bottom of the enclosure.
• the exchange surface between the sludge accumulated on the bottom of the enclosure and the supernatant is substantially equal to the entire surface of the horizontal section of the enclosure at the lower edge of the first deflector or the upper surface sludge.
• the first deflector, the second deflector and the vertical partition are, in addition to the supply and evacuation conduits, the only organs placed inside the enclosure of the septic tank.
• the enclosure forms a single compartment not separated into two separate compartments by a transverse partition.
• the invention relates to a method of treating domestic wastewater in which, successively:
• the water leaving the second filter has:
• FIG. 1 is a schematic view illustrating both the components of an installation and the steps consisting of a method of treating domestic wastewater according to the invention
• FIG. 2 is a schematic view in vertical and longitudinal section of a septic tank of the installation and the method according to the invention
• Figure 3 is a schematic view in transverse and vertical section along line 33 of Figure 2;
• FIG. 4 is a top view of a filter for the retention of bacterial contamination of effluent according to the invention or for the retention of organic materials from effluents; this or these filters forming part of the installation of FIG. 1 or being used in the corresponding method;
• FIG. 5 is a bottom view of the filter shown in Figure 4;
• Figure 6 is a sectional view of the filter along line AA 'of Figures 4 and 5;
• - Figure 7 is a perspective representation of a distribution pipe of the distribution pipe network of a filter according to the invention;
• FIG. 8 is a partial sectional view of a distribution pipe provided with a protective means and with which are associated distribution means;
• FIG. 9 is a representation of the granulometric zone of the filtering sand intended to fill the sand filters, according to standard P16-603 references DTU 64.1 of December 1992, edited and published by the French Association for Standardization (AFNOR).
• a domestic wastewater treatment installation according to the invention comprises from upstream to downstream:
• a pre-filter 2 filled with pozzolan or equivalent material; a first filter 3 comprising filtering means in the form of at least one granular filtering layer with a porosity of between 0.2 and 5 mm approximately, capable of ensuring the retention of a substantial part of the organic materials of the effluents; and a second filter 4 for retaining the bacterial contamination of the effluents.
• the installation also includes:
• the filter 4 has an inlet 10 for the water to be treated corresponding to the duct 8, an outlet il for the treated water corresponding to the duct 9 and filtration means interposed between the inlet 10 and the outlet 11.
• the filter 4 is supplied with water to be treated, at its inlet 10, via - in the embodiment shown - a siphon 12 which can be started by a pressure bell situated in a supply tank 12a.
• the siphon 12 receives the water to be treated from the first filter 3.
• the filter 4 can however be distinct from the siphon 12.
• the inlet of the filter therefore corresponds here at the inlet 10a of the siphon 12 located in the feed tank 12a. This siphon 12 then feeding the input 10 of the filter 4.
• This siphon 12 which can be primed causes a supply of filter water 4 to pack.
• the priming of the siphon 12 can be adjusted so that the filter 4 receives a packet of water to be treated only when the previous one has been successfully. This allows a better distribution of water in the filter as well as better purification.
• the filter 4 is placed substantially horizontally and on the ground surface. It can however be partially or totally buried.
• the filtration means of the filter 4 include:
• distribution means 17 associated with the distribution pipe network 13 and intended to ensure diffusion of the water to be treated towards the filtering means 16.
• the filter means 16 are in the form of a granular filter layer.
• This granular filtering layer 16 is or comprises at least one layer of washed silica sand, stable in water.
• This sand has a particle size curve which fits into the spindle shown in Figure 9 to which we refer, expressly for this purpose.
• the thickness of the layer is between 0.5 and 1 m. It is preferably equal to or about 60 cm.
• the network of distribution pipes 13 is adjacent to a first surface 16a of the granular filtering layer 16. It can be located outside or inside this granular filtering layer 16.
• the network of distribution pipes 13 is placed outside the granular filtering layer 16.
• this network of distribution pipes 13 is provided with chimneys allowing its ventilation.
• the network of drainage pipes 14 is adjacent to a second surface 16b of the filtering granular layer 16. It can also be located outside or in the filtering granular layer 16. In the embodiment considered on the FIG. 6, the network of drainage pipes 14 is placed in a draining layer 17b situated below the filtering granular layer 16, the filtering layer and the draining layer being separated by a geotextile of grammage approximately 100 g / m 2 .
• the distribution pipe network 13 comprises at least one ply of several distribution pipes 13a spaced transversely with respect to each other and in communication with each other, particularly in the vicinity of the inlet 10 of the filter 4.
• the distribution pipes 13a are in communication with each other via communication pipes 13b placed transversely to the longitudinal axis 13c of the distribution pipes 13a at their ends 13d, 13e.
• the distribution pipes 13a are preferably made of PVC and have a diameter of approximately 40 mm.
• the distance d which separates the longitudinal axes 13c from distribution pipes 13a is preferably about 1 m.
• the network of drainage pipes 14 comprises at least one ply of several drainage pipes 14a spaced transversely with respect to each other and in communication with each other in the vicinity of the outlet il of the filter 4.
• the network of drainage pipes 14 has the same configuration as the networks of distribution pipes 13.
• the drainage pipes 14a are therefore in communication with each other via communication pipes 14b placed at the ends 14d, 14e of drainage pipes 14a transversely to the longitudinal axis 14c of the drainage pipes 14a.
• the communication pipes 14b situated at the end 14e of the drainage pipes 14b situated at the end 14e of the drainage pipes 14a are in communication with the outlet 11 of the filter 4.
• the drainage pipes 14a are also preferably made of PVC and have a diameter of approximately 100 mm.
• the distance d which separates the axes 14b from the drainage pipes 14a is here the same as in the case of the network of distribution pipes 13.
• the distribution means 17 associated with the network of distribution pipes 13 are in the form of a water absorption and diffusion sheet interposed between the network of distribution pipes 13 and the filtering means 16, namely the granular filter layer. 16.
• the distribution means 17 are in the form of bands 17a for absorbing and diffusing water, preferably about 50 cm in width, these bands 17a being interposed between the network distribution pipes 13 and the filtering means 16.
• This tablecloth or these absorption and diffusion bands 17a comprise a geotextile with a grammage of approximately 750 g / m2 and can be in the direction of diffusion of the water, in the form of a draining layer 17b and a fine filter layer 17c preferably made of polypropylene.
• the distribution pipes 13a are placed in the middle part of the absorption and diffusion bands 17a.
• the distribution pipes 13a are provided with perforations 15 distributed longitudinally in their transverse walls and arranged substantially perpendicular to the thickness 16c of the granular filtering layer 16.
• the perforations 15 are cylindrical in shape and have a diameter of at least about 3 mm so as not to risk being blocked.
• These perforations 15 are distributed longitudinally with an interval of approximately 30 cm which allows good distribution of the water by using all of the perforations 15 present in the distribution pipes 13a.
• the distribution pipes 13a are also provided with overflow orifices 18 also distributed longitudinally but opposite the first surface 16a of the filtering granular layer 16.
• These orifices overflow 18 preferably have a diameter of about 10 mm and are placed alternately with the perforations 15.
• the distribution pipes 13a are covered respectively with a protective means 19 intended to prevent the obstruction of the perforations 15 or the overflow orifices 18
• This protection means 19 is in the form of a gutter lo
• the inverted gutters 19 have a diameter of about 100 mm.
• a protective layer 20 can be provided in which the distribution pipe network 13 is located.
• This protective layer 20 is adjacent to the filtering granular layer 16 at its first surface 16a and is preferably a layer of washed gravel, about 5 to 10 cm thick.
• the filter 4 comprises an outer casing 21 in which are housed the two networks of distribution pipes 13 and drainage respectively 14, the filter means 16 interposed between the two networks 13 and 14 and the distribution means 17 associated with the network of distribution pipe 13, this casing comprising the inlet 10 and the outlet 11.
• the casing 21 has a U shape but it can also have a U shape, the opening of which is closed.
• this casing 21 can be replaced by a concrete tank with sealed walls produced on site.
• the second filter 4 which has just been described is compact, that is to say that its dimensioning is smaller than those recommended in practice.
• the second filter 4 is dimensioned between 0.2 and 0.9 m 2 / inhabitant equivalent and in particular around 0.6 m / inhabitant equivalent.
• the first filter 3 can have a general structure similar or analogous to that of the second filter 4.
• the first filter 3 comprises, in the embodiment considered here, zeolite aggregates, having a particle size between 0 , 1 and 10 mm approximately.
• This layer comprises for example either entirely aggregates between 2 and 5 mm, or two sub-layers, an upper of 2 to 5 mm and a lower of 0.2 to 2 mm.
• the zeolite aggregates allow, thanks to the presence of intergranular interstices, excellent air circulation and therefore good growth of the purifying microorganisms.
• the zeolite fixes the purifying biomass well and thus allows a good removal efficiency of the carbonaceous polluting load of the effluents.
• the zeolite consists of microporous grains which allow water to flow gravity between the grains in the event of high flow, and by capillarity from one grain to the other in the event of low flow.
• the zeolite has interesting properties for eliminating nitrogen pollution.
• the strip geotextile gradually loses part of its permeability and diffuses the water to be treated gradually towards the filtering granular layer 16, resulting in an improvement in the distribution of the surface water.
• the septic tank 1 comprises a rigid enclosure 22; a waste water supply pipe 5; an exhaust duct 6 to the pre-filter 2.
• the septic tank 1 also comprises means 23 for settling by depositing in the bottom 24 of the enclosure 22 the heaviest materials or sludge B and by accumulation on the free surface S of the fats of light particles G; and at least partial liquefaction of these materials B, G by anaerobic fermentation.
• the septic tank 1 finally comprises means 19 for protecting the part of the installation placed downstream (pre-filter 2, filters 3 and 4) in order to prevent its clogging, integrated into the enclosure 1.
• the means 23 for settling and liquefaction and the means 19 for protection are placed in a single department of the enclosure 22.
• the enclosure 22 comprises two identical or substantially similar parts from each other, namely a lower shell 25a and an upper shell 25b.
• Each of the shells 25a, 25b has in longitudinal cross section and in transverse cross section, a generally isosceles trapezoidal shape.
• the two shells 25a, 25b are joined to each other by their large open common base 26.
• the lower shell 25a comprises, in addition to the bottom 24 forming a small base, two inlet end walls 27a and outlet 28a and two side walls 29a, 30a all inclined relative to the vertical by an angle of approximately 30 °.
• the upper shell 25b has an upper cover 31 forming a small, flat and horizontal base, two inlet end walls 27b and outlet 28b and two side walls 29b, 30b.
• the end walls 27b, 28b and side 29b, 30b are inclined to the vertical in the same manner as the end walls 27a, 28a and side 29a, 30a.
• the walls 27b, 28b, 29b, 30b of the shell 25b are connected to the walls 27a, 28a, 29a, 30a and the shell 25a in the base 26.
• the base 26 is therefore located halfway between the bottom 24 and the cover 31.
• the supply duct 5 forms a double bend folded back on itself comprising a horizontal upstream section 34, a vertical intermediate section 35 and a also horizontal downstream section 36.
• the upstream section 34 crosses the inlet end wall 27b in the vicinity of the cover 31.
• the downstream section 36 is directed as a whole towards the end wall 27a, 27b of the enclosure 22 so that the effluents coming from the conduit d 'lead 5 are directed towards this wall.
• the outlet 37 of the downstream section 36 is cut in the form of a gutter in order to be open upwards so that the effluents are also directed upwards and this in the direction of the arrows FI (FIG. 2).
• the septic tank 1 also comprises a first deflector 38 placed in the enclosure 22 transversely, at least substantially at the outlet 37 constituting at least in part the means 23.
• the first deflector 38 extends over all or at least a part substantial the width of the enclosure 22, that is to say between the side walls 29a, 29b on the one hand and 30a, 30b on the other hand.
• the first deflector 38 has the function of improving the settling and of limiting the progression of the turbulence towards the bottom 24 of the enclosure 22. There follows a circulation of water according to the arrows F2 (FIG. 2).
• the first deflector 38 is inclined in particular from 35 ° to 55 ° on the vertical and in particular by approximately 45 °, from the bottom 24 towards the cover 31 and from the inlet end walls 27a, 27b towards the walls ends exit 28a, 28b. If we call H the height of the water in the enclosure, height defined by the position of the discharge duct 6 as will be seen later, the center of the first deflector 38 is located between 0.65 H and 0.75 H and in particular about 0.70 H and this from the bottom 24.
• the lower edge 39 of the first deflector 38 is located between 0.5 H and 0.60 H and in particular approximately 0.55 H from the bottom 24.
• the upper edge 40 of the first deflector 38 is located between 0.75 H and 0.85 H and in particular approximately 0.80 H from the bottom 24.
• the first deflector 38 is located about one third of the length of the enclosure, 22 (i.e. between the end walls 27a, 27b and 28a, 28b ) from the inlet end walls 27a, 27b. More generally and to take into account a possible total volume of the upper septic tank, it is preferable that the first deflector 38 is not too far from the end walls 27a, 27b. For this reason, the first deflector 38 is generally located at a distance from the junction of the two walls 27a, 27b equal to or on the order of 5.5 to 7.7 times and preferably on the order of 6 to 7 times the diameter of the supply duct 5. Or, as a variant, this distance is equal to or of the order of 0.6 H.
• the first deflector 38 thus defined leaves on the one hand between its lower edge 39 and the bottom 24 a large lower passage 41 and on the other hand between its upper edge 40 and the free surface S a smaller upper passage 42.
• the lower passage 41 allows the passage of heavy materials or sludge B while the upper passage 42 allows that of grease and light particles G.
• the first deflector 38 can be fixed at its two lateral ends to the lateral walls 29a, 29b, 30a, 30b of the enclosure 22.
• the discharge pipe 6 placed horizontally defines the level of the free surface S.
• the horizontal upstream section 34 of the supply pipe 5 is located above the free surface S and this to avoid any effluent backflow through the pipe d brought 5.
• the free surface S is, for its part, located at a distance H from the bottom 24 which is of the order of 0.7 K to 0.9 K and preferably equal to or close to 0.8 K, K being the distance between the bottom 24 and the cover 31.
• a vertical partition 43 located partly above and partly below the free surface S.
• the lower edge 44 of the vertical partition 43 located between 0.10 H and 0 , 20 H and in particular is equal to or close to 0.15 H approximately from the free surface S.
• the free surface S is itself located substantially halfway up the partition 43.
• the discharge duct 6 is also associated with a second deflector 45 comprising a lower section 45a inclined from the bottom 24 towards the cover 31 and from the end walls 27a, 27b to the end walls 28a, 28b.
• the vertical partition 43 is located at least substantially perpendicular to the lower edge 46 of the second deflector 45.
• the vertical partition 43 and the second deflector 45 define a passage 47 for clear waters.
• This passage 47 has an at least substantially vertical inlet opening limited by the lower edges 44, 46 of the partition 43 and of the second deflector 45, then an elbow limited by the lower section 45a to prevent the passage of floating materials, then a outlet opening in a vertical section in communication with the evacuation duct 6.
• End side partitions 48 (FIG.
• a grid 49 is placed horizontally in the passage 47 towards the outlet below the free surface S. Its position is such that it is easily accessible by the sight 32 placed vertically. It is removably mounted.
• Another vertical grid 50 is placed in the passage 47 at the entrance, extending the partition 43 down to the edge 46.
• the waste stopped by the grid 50 can settle or float freely as soon as it stops the current in the septic tank.
• the vertical partition 43 and the second deflector 45 have an identical or similar width which can be limited to approximately 2.5 times to 6 times and in particular to approximately 4 times the diameter of the evacuation duct 6 (FIG. 3).
• the spacing between the lower free edges 44, 46 of the partition 43 and of the second deflector 45, that is to say the height of the inlet opening of the passage 47 can be between 0.9 P and 1, 1 P and in particular equal to or close to P, P being the submerged depth of the vertical partition 43.
• This spacing can also be between 0.10 H and 0.20 H approximately and in particular be equal or close to 0.15 H.
• the lower free edge 44 of the partition 43 is situated substantially at the same level as a stop 45b separating the lower section 45a of the second deflector 45 from an upper section 45c at least substantially vertical and connected to the discharge duct 6 and even projecting above it in a section 45d.
• the spacing between the upper section 45c and the vertical partition 43 can be of the same order of magnitude as the height of the entry opening of the passage 47, in particular between 1 and 1.5 P approximately or equal or 0.2 H order
• the supply duct 5, the discharge duct 6 as well as the vertical partition 43 and the second deflector 45 are entirely located in the upper shell 25b and the first deflector 38 located at least partially in the upper shell 25b and in the vicinity from base 26.
• the first deflector 38, the second deflector 45, the partition 43 are of limited size allowing their passage through the manhole 32.
• the lower edge 39 of the first deflector 38 determines the upper admissible level for the sludge accumulated on the bottom 24 of the enclosure 22.
• the exchange surface between the sludge B accumulated on the bottom 24 of the enclosure 22 and the supernatant liquid E is substantially equal to the entire surface of the horizontal section of the enclosure 22 at the lower edge 39 of the first deflector 38 or at the level of the upper surface of the sludge B.
• An opening 51 pierced in the upper part of the supply conduit 5 allows the realization of a free, continuous and permanent communication for the passage of the air necessary for the operation of the septic tank all waters, from the evacuation conduit 6 which does not immerse in the liquid contained in the pit and the supply pipe 5.
• the first deflector 38, the second deflector 45 and the vertical partition 43 are, in addition to the supply and evacuation conduits 5, 6, the only members placed inside the enclosure 22.
• the enclosure 22 therefore forms a compartment single, not separated into two completely separate compartments by a vertical partition 43.

Landscapes

• Health & Medical Sciences (AREA)
• Clinical Laboratory Science (AREA)
• Life Sciences & Earth Sciences (AREA)
• Hydrology & Water Resources (AREA)
• Engineering & Computer Science (AREA)
• Environmental & Geological Engineering (AREA)
• Water Supply & Treatment (AREA)
• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Treatment Of Biological Wastes In General (AREA)
• Filtering Materials (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=9489522

Family Applications (1)

Country Status (6)

Families Citing this family (6)

Family Cites Families (7)

• 1996
  • 1996-02-23 FR FR9602276A patent/FR2745195B1/fr not_active Expired - Fee Related
• 1997
  • 1997-02-21 US US09/125,739 patent/US6440307B1/en not_active Expired - Fee Related
  • 1997-02-21 BR BR9715046-0A patent/BR9715046A/pt not_active Application Discontinuation
  • 1997-02-21 CA CA002247519A patent/CA2247519A1/fr not_active Abandoned
  • 1997-02-21 EP EP97906243A patent/EP0885041A1/de not_active Withdrawn
  • 1997-02-21 WO PCT/FR1997/000326 patent/WO1997030770A1/fr not_active Application Discontinuation

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events