EP1888470A1

EP1888470A1 - A sewage treatment and recirculation unit

Info

Publication number: EP1888470A1
Application number: EP06704379A
Authority: EP
Inventors: Rafal Lusina
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-02-01
Filing date: 2006-01-26
Publication date: 2008-02-20
Also published as: WO2006083186A1

Abstract

The subject of the invention is a sewage treatment and recirculation unit, being applicable in treatment plants for single homes, housing estates and small industrial objects. It is characterised by the settling chamber (1) is connected by a discharge pipe (4) with the first overflow chamber (5), in which a pump (6) is mounted, connected by a hydraulic pipe (7) with the upper zone of the second overflow chamber (8), having a lower outlet with an (11) located above the upper level of the biofilter (2) of the settling chamber (1) and connected advantageously with the sprinkler (3) in the settling chamber (1), and the lower outlet connected with the discharge pipe (10).

Description

A sewage treatment and recirculation unit

The subject of the invention is a sewage treatment and recirculation unit, being applicable in treatment plants for single homes, housing estates and small industrial objects.

In order to keep the microorganisms in the biofilter it should be kept permanently moist. In previously known solutions the moisturizing of the biofilter is performed by diverting a part of the sewage stream passing through the plant and spraying it over the biofilter. For this, an additional hydraulic installation with an electric pump is used.

Such solutions use a part of electric energy to sustain the recirculation process and require the installation of additional hydraulic pipes.

The solution shown here eliminates those flaws and inconveniences.

The nature of the invention, being a sewage treatment and recirculation unit comprising a settling tank, a biodegradation chamber with filtering material and an overflow sump with a pump, consists of the biodegradation chamber settling tank being connected by a discharge pipe to the first overflow chamber, where a pump is mounted, connected with a hydraulic pipe to the upper zone of the second overflow chamber, which has a lower outlet with a discharge pipe located above the upper level of the filtering material in the biodegradation chamber, and connected advantageously with a sprinkler in the biodegradation chamber, and an upper outlet, connected by a discharge pipe with the sewage distribution system located in such a manner that the volume of the chamber between a level surface at the level of its lower generating line and a level surface at the level of the lower generating line of the pipe outlet is equal to or larger than the volume of the chamber between a level surface at the level of the lower generating line of the discharge pipe connecting the settling tank with the first overflow chamber and the minimum sewage level in the first overflow chamber.

It is advantageous when the overflow chamber is located directly above the biodegradation chamber body, and the discharge pipe has its outlet directly above the sprinkler.

It is also advantageous when the overflow chamber is monolithic with the biodegradation chamber body, or when it is an element placed on the biodegradation chamber.

It is also advantageous when the discharge pipe has an unclogger, being a lever arm mounted on an articulated joint to a part of the body or the overflow chamber, having on its free end a mandrel with its outer shape corresponding to the discharge pipe hole inner shape, or being a lever arm mounted on an articulated joint to a part of the body or the overflow chamber, having on its free end a mandrel with its outer shape corresponding to the discharge pipe hole inner shape, and the mandrel connected by a strand to a lever with an inlet pipe seal and a counterweight.

It is also advantageous when the biodegradation chamber has trickle trays under the sprinkler, below which a grid is mounted on which flaps of unwoven cloth are hung, and below the flaps of cloth a pump with pipes for recirculation of sewage is located, whereas the trickle trays, mounted parallel to the axes of grid arms are lengthwise elements with discharging openings, and the grid arms are angle bars with the edge where the external surfaces meet pointed downwards.

It is also advantageous when the sprinkler is a lengthwise, shaped element with side walls and an arcuate shape bottom, located rotatably on an axis perpendicular or parallel to the axes of grid arms, whereas the axis is placed outside of the symmetry plane of the part, and whereas the part has a counterweight and a rotation limiter mounted on the side of the axis. It is also advantageous when the sprinkler is a lengthwise, shaped element consisting of two containers with a cross-section similar to a triangle, with one common wall, with the rotational axis of the sprinkler placed in the plane of the common wall, above the meeting edge of all the walls and perpendicular to the axes of trickle trays, and the outlet of sewage intake pipe located above the sprinkler.

It is especially advantageous when the pump is located in the settling tank of the biodegradation chamber, in the overflow chamber connected with the biodegradation chamber, and is connected by a hydraulic pipe to the storage chamber, whereas the pipe outlet is located above the treated sewage discharge pipe level.

It is additionally advantageous when the storage chamber has a hydraulic pipe with an outlet in the last chamber of preliminary settling tank, with an outlet above the sprinkler, with an inlet in the tank wall, and with an inlet in the lower zone of the tank.

It is also advantageous when the storage chamber has the sewage discharge hole connected by a discharge pipe open at the top to an inlet in the bottom zone of the chamber.

The use of the invention's solution results in the following technical and usage effects:

- a single pump is used for the pumping of sewage for trickling and for recirculation,

- the uninterrupted process of biofilter sprinkling is guaranteed,

- a compact sewage flow installation is obtained,

- the biodegradation process is performed on the surface and within the entire volume of the unvowen fabric, since vital functions of biodegrading bacteria can persist there,

- the increase of the biological layer durability by keeping the unwoven cloth constantly moist,

- trickling of sewage precisely and on the entire width of the grid keeping the woven cloth up enables permanent moistening of the entire volume of the cloth, and thus maintains the biodegradation processes, - the ability to distribute the sewage on the entire width of the unwoven cloth flap, thanks to its flow in the channel of each of the grid arms,

- the ability to perform recycling of sewage flow, and thus increase the amounts of time sewage passes through layers of unwoven cloth,

- the ability to equalize the quality of sewage in case of uneven inflow,

- the use of the storage tank as a secondary settling tank,

- the use of the zone below the unvowen cloth for the denitrification of the sewage treatment process,

- the ability to cut off the recirculation process and direct the entire mass of the treated sewage to an external tank,

- small dimensions of the unit in comparison to its flow capacity,

- ease of removing of impurities,

- ease of exchange of the unit parts, especially the unwoven cloth grid

- low unit operating costs,

- low unit manufacturing costs,

- no servicing required.

An example subject of the invention is shown on diagrams on the drawing, where on the fig. 1 the vertical cross-section of the unit is shown, through the axes of both overflow chambers and the axis of the biodegradation chamber, in the first version of work, on the fig. 2 a cross-section of the unit is shown in the version with an overflow chamber above the body of the overflow chamber, and on the fig. 3 one version of the unclogger is shown and on fig. 4 the second version of the unclogger. Also on the fig. 5 a unit with one version of locating the flow pipes is shown, on the fig 6 a unit with another version of locating the flow pipes, on the fig. 7 the sprinkler in one version is shown and on fig. 8 in another version.

In the biodegradation chamber i the filtering material 2 is placed, being a biofilter, above which the sprinkler 3 is mounted, delivering sewage to the surface of the filtering material 2. Below the filtering material 2 a discharge pipe 4 is mounted, with an outlet in the first overflow chamber 5. In the first overflow chamber 5 a pump 6 is situated, pumping sewage through the pipe 7 to the second overflow chamber 8. The pump 6 has a limit switch 9, turning off the pump 6 at the minimum sewage level hmin in the first overflow chamber 5. The pipe outlet 7 in the second overflow chamber 8 is located above the axis of the discharge pipe K). The first overflow chamber 5_. and the second overflow chamber 8 have their bottom surfaces level. The second overflow chamber 8 has in its lower zone an opening for connecting to the sprinkler 3_. through the pipe 11. The opening is located so that the volume of the chamber 8 between a level surface at the level of the lower generating line of the discharge pipe K), and a parallel surface at the level of the lower generating line of the pipe JJ, is equal to or larger than the volume of chamber 5 between the minimum sewage level in the first overflow chamber 5, and a level surface at the level of the lower generating line of the discharge pipe 4. The cross-sectional surface of the pipe having the cut-off valve 31, is lower than the minimum cross-sectional surface of the pipe 7, as well as the discharge pipe K).

In the version shown on fig. 2, in the biodegradation chamber 1 a filtering element 2 is placed, being a biofilter or a grid with high-absorptivity unwoven cloth, above which a sprinkler 3 is located, delivering sewage above the surface of the filtering element 2. Below the filtering element 2 the pump 6 is placed, pumping sewage through the pipe 7 to the overflow chamber 8, located above the body of biodegradation chamber 1. The chamber 8 is formed monolithic with the biodegradation chamber body 1 or as a part to be placed on the chamber. The pump 6 has a limit switch 9, turning off the pump 6 at the minimum sewage level hmin and turning it on at the hmax level. The pipe outlet 7 in the overflow chamber 8 is located above the discharge pipe K) axis. The overflow chamber 8 has in its lower zone an opening for connecting to the zone of sprinkler 3 through the pipe H. The opening is located so that the volume of chamber 6 between the surface of the discharge pipe _.10 outlet, and the surface of the pipe 9 outlet is equal to or larger than the volume between the hmin pomp 6 cut-off level, and the hmax pomp 6 restarting level. The cross-sectional surface of the pipe H is lower than the cross-sectional surface of the discharge pipe K). The pipe 11 may have a flange or a valve, depending on the version, not shown on the drawing. Sewage for the biodegradation chamber 1 is delivered by the pipe 12,, with an outlet in the zone above sprinkler 3 or below sprinkler 3. The discharge pipe 9 of the chamber 6 has an unclogger 13_..

Depending on version the unclogger 13 consists of a lever arm 14, mounted on an articulated joint JJ_. to a part of the body or the overflow chamber 8, having on its free end a mandrel Jj5 with its outer shape corresponding to the discharge pipe JJ_. inner shape. In another version the unclogger _13_ consists of a lever arm 14, mounted on an articulated joint 15 to a part of the body or the overflow chamber_8, having on its free end a mandrel 16 with its outer shape corresponding to the discharge pipe H inner shape. To the mandrel 16 a strand j/7 is connected, joined with the lever 18_. having a seal 19 for the inlet pipe 7 and a counterweight.

In the subsequent versions shown on the fig. 5 and 6 the unit has a biodegradation chamber 1, connected by the pipe 2 with the last chamber of the preliminary settling tank 20. In the biodegradation chamber 1 a grid 21 is seated, with arms 22 having a shape of angle bars with the connecting edge of external surfaces pointing downwards. On each of the arms 22 of the grid 21 a flap 23 is hung made of unwoven cloth, especially of cloth with high inner absorptivity of liquids. Above the grid 21, on the axis 24, a swinging sprinkler 3_ is mounted. Sprinkler 3 is a container with shaped walls. Between the sprinkler 3 and the grid 21, perpendicular to the axis of grid 21, perpendicular to the axis of sprinkler 3_^ a unit of trickle trays 22 is seated, the trays being lengthwise elements with discharge openings 25. The width of the trickle trays unit 22 is approximately equal to the length of the sprinkler 3.

There are versions where the unit of trickle trays 22 may be replaced by a rectangular pan not shown on the drawing, with openings in the bottom, and a length and width approximately equal to the dimensions of the grid 21 when viewed from above.

In one of the versions, shown on the fig. 7, sprinkler 3 is a shaped element with an arcuate shape bottom, having a rotation axis 24 located some distance from the longitudinal symmetry axis and having a counterweight 26 and a rotation limiter 27 mounted on the side of the rotation axis.

In another version, shown on the fig. 8, sprinkler 3_ is a lengthwise, shaped element consisting of two containers with a cross-section similar to a triangle, with one common wall, with the rotational axis 24 of the sprinkler placed in the plane of the common wall.

Above the sprinkler 3 the outlet 28 of the pipe H is located.

Below the lower edges of the cloth 23 the sewage pump 6 is mounted. In one of the versions the pump 6 is mounted in the settling tank 29 of the biodegradation chamber L

In another version the pump 6 is mounted in the overflow chamber 29, connected hydraulically with the biodegradation chamber L

A hydraulic pipe 7 is connected to the pump 6, with an outlet in the storage tank 8, above the level of the opening of the discharge pipe JJ), delivering the sewage to the receiver, not shown on the drawing.

In one of the versions in the storage tank £ a hydraulic pipe 30 is placed, with an inlet in the lower zone of the tank 8, open from above and connected with the discharge pipe 10.

In another of the versions there is a hydraulic pipe H in the storage tank 8 with an inlet in the lower zone of the tank 8, and an outlet in one of the versions above the sprinkler 3, and in another of the versions in the preliminary settling tank 20.

There are versions with a valve 3_1 on the pipe LL

In specific versions the hydraulic pipe JJ, is connected with an overflow opening in the side of the storage tank S.

When the sewage treatment plant in the version shown on fig. 1 is working sewage is delivered to the settling tank 1, and is sprinkled by the sprinkler 3 on the biofilter 2. After passing through the biofilter 2, the sewage flows through the discharge pipe 4 to the first overflow chamber 5. After reaching the hmin level the pump 6 turns on, pumping sewage through the pipe 7 to the second overflow chamber 8.

When the settling tank 1 is intensively supplied with sewage, the sewage level in the first overflow chamber 5 raises. The pump 6 passes sewage to the second overflow chamber 8. A part of the sewage volume passes again to the sprinkler 3 through the pipe LL Due to the low diameter of the pipe ϋ, and thus a small flow throughput the level of sewage in the second overflow chamber 8 raises, until it reaches the level of the discharge pipe 10, by which sewage reaches the trickle zone, not shown on the drawing. In the case the settling tank 1 is supplied with small amounts of sewage, after passing through the biofilter 2 the sewage will pass by a discharge pipe 4 to the first overflow chamber 5. There after reaching the minimum level hmin, the pump turns on 6 and the sewage will pass to the second overflow chamber 8, from which it will flow through the pipe H to the sprinkler 3 and will be distributed by it on the biofilter 2.

In case of total lack of supply of sewage to the chamber 1, the sewage contained in the system will circulate between the biofilter 2, and the overflow chambers 5 and 8, sustaining biological life in the biological layer 2.

The recirculation process in both just described cases is enabled by the volume of the chamber 8, contained between the indicated surfaces, being equal or larger than the volume of the chamber 5 between the indicated surfaces.

There is also a possibility of cutting off the recirculation flow with the valve 31_ and directing entire sewage to the trickle zone.

In one of the versions shown on 2, during the operation of sewage treatment plant sewage is delivered to the biodegradation chamber 1 and is sprinkled by the sprinkler 3 above the filtering material 2. After passing through the filtering material 2, and after reaching by the sewage of the hmax level the pump 6 turns on, and pumps the sewage through the pipe 7 to the overflow chamber 8_^ until the h_mj_n level is reached.

The sewage then returns through the pipe JJ,, the sprinkler 3_. and the filtering material 2 to the biodegradation chamber L Due to the fact that sewage recirculation is much faster than sewage supply, before another load of treated sewage flows in the previous one is treated.

In the version where the inlet Yl is below the sprinkler 3, the sewage storage in the biodegradation chamber I must be a few times higher than a single dose of incoming sewage.

When the biodegradation chamber l_ is supplied with sewage, the new sewage is mixed with treated sewage, and the level of sewage rises. The pump 6 passes sewage to the overflow chamber S. A part of the sewage volume will pass again through the pipe JJ, to the sprinkler 3. Due to the low diameter of the pipe 11, or the flange on its end, and thus a small flow throughput the level of sewage in the second overflow chamber 8 raises, until it reaches the level of the discharge pipe K), by which sewage reaches the trickle zone, not shown on the drawing.

In order to protect the inlet of the pipe H from clogging versions with unclogger 13 are used.

In one version the uclogger 13 has a lever 14 with a mass that results in closing of the pipe H inlet in case of a low pressure of sewage in the chamber 8. When the level of sewage in the chamber 6 rises and pressure increases, the mandrel 16 will be pushed out of the hole, unblocking the flow.

In another version, in case sewage is not supplied by the pipe 5 to the chamber 8, the seal 19 will close the inlet of the pipe H, and the mandrel 16 will open the outlet of the pipe H. When sewage flows into the chamber 8 under the pressure of sewage the seal 19 will open the flow of sewage, and the mandrel 16 will close the outlet of the pipe H. This cyclic movement of the mandrel 16 in the hole of the pipe H causes the unclogging of the pipe H.

In case of total lack of supply of sewage to the chamber 1, the sewage contained in the system will circulate between the filtering element 2, and the overflow chamber 8, sustaining biological life in the filtering element 2, and thus will be treated above the required treatment level.

The recirculation process in both just described cases is enabled by the volume of the chamber 8, contained between outlets of pipes K) and H, being equal or larger than the volume between indicated h_max and h_mj_n levels.

In another version shown on fig. 5, fig. 6, fig. 7 and fig.8, the sewage collected in the preliminary settling tank 20, after raising above certain level or because of the sewage transporting pump not shown on the drawing flow through the pipe 28 above the sprinkler 3. In the sprinkler 3 they fill the volume of the chamber.

In one version the sewage collected in the sprinkler 3_, in an amount with a total mass higher than the turning moment of the counterweight 26 will cause the tipping of the sprinkler 3_ and pouring - distribution of sewage on the entire width of the trickle trays 22. From the trickle trays 22 the sewage is distributed through the openings 25 on the entire width of the grid 21, ensuring a thorough distributing of sewage through the entire width of the grid 21. After pouring of the sewage the counterweight causes the sprinkler 3_. to return to the filling position and the cycle begins anew.

In the second version sewage flows to one of the chambers of the sprinkler 3. The centre of gravity of the sewage filling the chamber on the arm in relation to the axis 24 will cause the tipping of the sprinkler 3 and pouring of its contents on the trickle trays 22, and from them through openings 20 on the grid 4 with the unwoven cloth 6. The chamber lies on trickle trays 22, and below the outlet 28 of the pipe JJ,, a second chamber of the sprinkler 3 is placed. The filling cycle begins anew. In this version it is possible to dose the sewage to both sides of the trickle trays 22.

Sewage sprinkles on the flaps of unwoven cloth 23, in which biodegradation bacteria live, and the process of sewage biodegradation starts. Sewage passes under the cloth 23, where it is distributed in a tray made from an angle bar throughout the entire length of arms 22 of the grid 21, increasing the effect of sprinkling of flaps of unwoven cloth 23. After passing through the flaps of cloth 23 sewage after biodegradation process falls gravitationally to the bottom of the biodegradation chamber I.

In the version with the pump 6 situated in the overflow chamber 29, under the flaps of unwoven cloth 23, thanks to the mixing of treated, oxygenated sewage with oxygen-free ones the process of sewage denitrifϊcation occurs. This volume of the biodegeneration chamber J, may be filled fit spacing elements that increase the effectiveness of the process.

The pump 6 with the limit switch 9 pumps sewage through the hydraulic pipe H to the storage tank 8_., filling it above the level of the outlet of the pipe 11. Through this pipe sewage flows either back to the preliminary settling tank 20, or flow above the sprinkler 3. In both cases sewage flows again through the unwoven cloth 23 and the sewage biodegradation process repeats itself.

Depending on version, sewage may either flow from the storage tank 8 from the sewage level at the opening of the hydraulic pipe JJ,, or be taken from the bottom of the tank 8.

In the case where recirculation is too high, it is possible to throttle the valve 3J, and lower the recirculation. When the valve 3J, is closed completely, recirculation stops and after sewage passes once through the unwoven cloth 23 the pump 6 pumps the entire sewage volume through the storage tank 8 of the sewage receiver.

In case of total lack of supply of sewage, the recirculation of flow in closed circuit enables the sustaining of biodegrading bacterial life.

Claims

1. A sewage treatment and recirculation unit comprising a settling tank, biodegradation chamber with filtering material and an overflow sump with a pump, characteristic in that the biodegradation chamber settling tank (V) is connected by a discharge pipe (4) to the first overflow chamber (5), where a pump is mounted (6), connected with a hydraulic pipe (7) to the upper zone of the second overflow chamber (8), which has a lower outlet with a discharge pipe (J_l) located above the upper level of the filtering material (X) in the biodegradation chamber (I), and connected advantageously with a sprinkler (3) in the biodegradation chamber (V), and an upper outlet, connected by a discharge pipe (H)) with the sewage distribution system located in such a manner that the volume of the chamber (8) between a level surface at the level of its lower generating line and a level surface at the level of the lower generating line of the pipe (11) outlet is equal to or larger than the volume of the chamber (5) between a level surface at the level of the lower generating line of the discharge pipe (4) connecting the settling tank (I) with the first overflow chamber (5) and the minimum sewage level in the first overflow chamber (5).

2. A unit according to claim 2, characteristic in that the overflow chamber (8) is located directly above the biodegradation chamber body (V), and the discharge pipe (VV) has its outlet directly above the sprinkler (3).

3. A unit according to claim 2, characteristic in that the overflow chamber (8) is monolithic with the biodegradation chamber body (1).

4. A unit according to claim 2, characteristic in that the overflow chamber (6) is an element placed on the biodegradation chamber (1).

5. A unit according to claim 2, characteristic in that the discharge pipe (11) has an unclogger (13).

6. A unit according to claims 1 or 5, characteristic in that the unclogger (13_) is a lever arm (14) mounted on an articulated joint (15) to a part of the body or the overflow chamber (8), having on its free end a mandrel (16) with its outer shape corresponding to the discharge pipe (JU) hole inner shape.

7. A unit according to claim 1 or 5, characteristic in that the unclogger (13) is a lever arm (14) mounted on an articulated joint (15) to a part of the body or the overflow chamber (8), having on its free end a mandrel Q6) o with its outer shape corresponding to the discharge pipe (H) hole inner shape, whereas the mandrel (16) is connected by a strand (17) to a lever (18), with an inlet pipe (7) seal (19) and a counterweight.

8. A unit according to claim 1, characteristic in that the biodegradation chamber (1) has trickle trays (22) under the sprinkler (3), below which a grid (21) is mounted on the arms of which, being trays (22) flaps of unwoven cloth (23) are hung, and below the flaps of cloth (23) a pump (6) with pipes (H, 13) for recirculation of sewage is located.

9. A unit according to claim 8, characteristic in that the trickle trays (22), mounted parallel to the axes of grid arms (2T) are lengthwise elements with discharging openings (20).

10. A unit according to claim 8, characteristic in that the grid (2JJ arms (22) are angle bars with the edge where the external surfaces meet pointed downwards.

l l.A unit according to claim 1, characteristic in that the sprinkler (3) is a lengthwise, shaped element with side walls and an arcuate shape bottom, located rotatably on an axis (24) perpendicular or parallel to the axes of grid (21) arms (22), whereas the axis (24) is placed outside of the symmetry plane of the part, and whereas the part has a counterweight (26) and a rotation limiter (27) mounted on the side of the axis (24).

12.A unit according to claim 1, characteristic in that the sprinkler (3) is a lengthwise, shaped element consisting of two containers with a cross- section similar to a triangle, with one common wall, with the rotational axis (24) of the sprinkler (3) placed in the plane of the common wall, above the meeting edge of all the walls and perpendicular to the axes of trickle trays(22).

13.A unit according to claim 1, characteristic in that the pipe outlet (H, 28) of the sewage intake is located above the sprinkler (3).

14.A unit as per the claim no 1, characteristic in that the pump (6) is located in the settling tank (29) of the biodegradation chamber (!).

15.A unit according to claim 1, characteristic in that the pump (6) is located in the overflow chamber (29), connected with the biodegradation chamber

(I)-

16.A unit according to claim 1, characteristic in that the pump (6) is connected by a hydraulic pipe (13) to the storage chamber (8), whereas the pipe outlet Q3_) is located above the treated sewage discharge pipe (10) level.

17.A unit according to claim 16, characteristic in that the storage tank (8) has a hydraulic pipe (U) with an outlet in the last chamber of preliminary settling tank (20).

18.A unit according to claim 16, characteristic in that the storage tank (8) has a hydraulic pipe (ϋ) with an outlet above the sprinkler (3).

19.A unit according to claim 16, characteristic in that the storage tank (8) has a hydraulic pipe (JJ,) with an inlet in the tank wall (8).

20. A unit according to claim 16, characteristic in that the storage tank (8) has a hydraulic pipe (JJ,) with an inlet in the lower zone of the tank (8).

2 LA unit according to claim 9, characteristic in that the storage tank (8) has the sewage discharge hole (K)) connected by a discharge pipe open at the top (32) to an inlet in the bottom zone of the chamber