FILM-FLOW PACKING FOR BIOLOGICAL TREATMENT OF FLUIDS

Abstract: The invention relates to plastic packing for biological treatment of fluids, comprising a series of plates packed without the use of adhesive, provided with convex and concave ribs (8), wherein inclined channels with corrugated side-walls are arranged between the adjacent sheets (1). The sheets (1) are formed by M-profiles (2), the jointing lines (5) and centrelines (7) of M-profiles (2) are broken along the full height of the packing and are at a maximum of 30° to the vertical; the corrugated parts are ribbed surfaces (8) formed only on the shanks (3) of the M-profiles (2), so that there is a flat strip without ribs on both sides of the jointing lines (5) of the profiles. According to one embodiment (Figure 6) the plastic sheets are jointed oppositely to (facing) each other so that the shanks (3) of M-profiles (2) end in a point of junction. According to another embodiment (Figure 7), the sheets (1) are turned in the same direction, jointed and spaced at a distance of 1/2 of an M-profile (2), so that the shanks of M-profiles of one sheet lie in a trough (4) on the upper part of M-profiles (2) on the adjacent sheet.

Description: The invention relates to film-flow packing treat­ ment of fluids, comprising a series of plates provided with conca e and convex ribs, wherein inclined channels with corrugated sides are formed at an angle between the adjacent plates packed together. As is known, the quality of water depends on its physical, chemical and biological properties. Preser­ vation of the water's quality, adequate purification of the sewage waters have become a central problem for the environment protection in recent years. The various technologies of the water and sewage purification include physical, chemical and biological processes. In a version of the biological processes the so-called drip bodies are used as the primary pu­ rification phase of mainly multiphase sewage water pu­ rification technologies. Their application enables one to carry out active sludge biological purification technology at higher efficiency. The packing of the biological drip bodies contains various materials, in the wake of the development near­ ly exclusively plastic packings are used today. The packing arranged on top of each other, built up as tower form the drip bodies with a water distributor on top of the tower. According to the principle of operation of the biological drip bodies the waste or sewage water flows down intermittently or continuously on the biological film developing on the surface of packings. This brings about coagulation and absorption of the pollutant, in the course of which the microorganic culture forming the biological film dissolves the solute of water to be utilized for gaining energy and cell synthesis. The overmultiplied biological film fractions agglomerate in a sedimentator, on through the cell-free enzyme activity of the microorganisms are decomposed to a material which diffuses through the cell wall and thus parti­ cipates in the metabolism process. The oxygen required for biochemical oxidation is supplied by the air passing through the packing. Flowing down in the drip body the BOI₅ value of the waste waters diminishes exponentially. Thus the packing used in the biological drip bodies must meet several requirements: Surface related to unit volume of the packings covered by the biological film has to be as large as possible. At the same time the voids volume too has to be large in the packing to have sufficient free cross section for the filmy downflow of the waste water and adequate oxygen supply should be available. Apart from this, packings have to be resistant against chemical, biological and physical effects and they must possess adequate statical strength in order that the biological film should be able to carry the weight of water and several packing units arranged on each other. Further obvious requirements are the easy, simple and fast production of the packings, as well as their fast and simple incorporation, operation and maintenance. In the spirit of the above efforts several known so­ lutions were born. One of the most familiar versions is described in the GB-PS 1 065 612 and 1 080 991. The elements are plastic sheets with straight or curved generatrix and accordion-like corrugated surface. These are generally arranged alternately with flat sheets so that the elements are turned opposite each other. The fundamental shortcoming of the construction is that as a result of using flat sheets to increase the mechanical strength, the specific surface is re­ latively small, 85 m²/m³, which results in poor effici­ ency. A solution is also used, where the packing consists of sheets corrugated in strips, and the sheets are provided with reticular reinforcing elements on the top and bottom. There is no closed channel system and though its specific surface is larger than that of the earlier mentioned solutions, the mechanical loadability of the packing is low. In the DE-PS 1 299 665 a packing is described which consists similarly of sheets folded as an accordion. Corrugations of the adjacent sheets intersect each other and the sheets are made of moisture absorbing material. The specific surface of the elements is relatively small, the mechanical strength is low, they are unsuitable for use in biological drip bodies. A solution is also known /see DD-PS 58 104/ which consists of trapezoid corrugated sheets. Flat sheets are arranged between corrugated sheets with ob­ long slots on the corrugated sheets. The specific sur­ face is small, mechanical strength is poor, field of application is mainly contact of liquid and gas. The plastic packing described in the HU-PS 172 169 represents definite progress compared to the earlier men­ tioned solutions. This is provided with corrugated through channels separated from each other, where the channels are regular hexagonal cross sections, in any ho­ rizontal section of at least one part of the packing. The longitudinal axes of the channels in the vertical plane consist of opposite sections following each other at least in part, and preferably two adjacent sides of each channel are provided with corrugations in cross direction to the longitudinal axis. This construction enables an increase in the spe­ cific surface to 135 m²/m³ and yields very good results. However it has two fundamental drawbacks: the sheets forming the packing are assembled with the use of adhesive. This is expensive, for it requires filler material and further aids, the gluing technology entails the risk of accident, since the applied solvents are poisonous and represent gas and explosion hazard. Further drawback is that the longitudinal axes of the channels are at a relatively wide angle to the vertical /30-50°/. Thus - as a result of gravitation - the water flows on the lower part of the channels during operation. This means that mainly in case of heavy surface load the surface participating in intensive purification may be reduced to 50 % of the total surface. Hence operation of these packing units is flexible against change of load only in a relatively narrow range. Clogging, inundation or other failures of the packing requiring repair, maintenance frequently occur even during the most careful operation of the biologic­ al drip bodies. Jointing the sheets with adhesive is un­ favourable in this respect too, for the sheets cannot be separately replaced, and cleaning, maintenance are difficult. An aim of the present invention is a reduction of the described deficiencies and providing a plastic packing exposable to heavy load particularly for biologic­ al drip bodies, the production, assembly, repair and maintenance of which are inexpensive, fast and simple, and as a result of large specific surface the operation will be more efficient and economical. Therefore, the sheets of the packing according to the present invention are formed with M-profiles provid­ ed with regularly repetitive convex and concave sheets jointed to each other without the use of adhesive, where channels with corrugated side-wall are arranged at an angle, the jointing lines and centrelines of the M-pro­ files are unbroken in the full height of the packing and are maximum at 30° to the vertical, furthermore the corrugated parts are ribbed surfaces formed only on the shanks of the M-profiles so that flat strips without ribs are on both sides of the jointing line of the profiles. In the packing according to the invention the sheets are jointed without adhesive. The M-profiles may be flat or curved surfaces. The jointing lines and centrelines of M-profiles are at 5° to the vertical in a practical construction. The ribbed surface is formed preferably by M-­ profiles or alternately M and V-profiles, where the jointing lines and centrelines of the profiles consist­ ing of flat sheets are horizontal. In given case the profiles may be rounded at their tips and joints of the shanks. The tips and shanks are preferably at an angle of approximately 90°. Length of the upper branches of the M-profiles forming the sheets is 1-200 mm, preferably 2 mm. Width of the flat strips at their edges is similarly 1-200 mm, preferably 3 mm. Length of the profile shanks is 10-­ 200 mm, preferably 25 mm. Height of the M and/or V-profiles forming the ribbed surface is 2-16 mm, preferably 5 mm. The angle between the profile shanks is preferably 60°. Length and width of the sheets forming the pack­ ing are preferably 500-3000 mm, size of the sheets in a practical construction is 500x1000 mm. According to a version of the invention the sheets forming the packing are jointed opposite each other so that shanks of the M-profiles end in a point of junction. According to another version the sheets are turned in the same direction, spaced and jointed to each other at a distance of 1/2 M-profile so that the shanks of M-profiles on one sheet fit into the trough on the upper part of M-profiles on the adjacent sheet. The plastic sheets forming the packing may be made of polyethylene, polystyrene, polypropylene, polyvinyl­ chloride or hard polyethylene foil with vacuum moulding. The fundamental advantage of the plastic packing according to the invention is that its specific surface can be increased even to 500 m²/m³, which is multiple of the hitherto best solution. Its operation is flexible even under high hydraulic, or surface load, thus the amount of charge built in for the given capacity can be reduced by 30-40 %. Two types of packing can be constructed from the uniformly shaped plastic sheets according to whether the sheets are jointed by turning them in the same direction or opposite each other. The jointing is shape-retentive, this gluing is unnecessary. At the same time in case of cleaning or failure it is easily assembled and disassembl­ ed, and each sheet can be separately replaced. The voids volume is large and the angular deflec­ tion of the channels is small in relation to the ver­ tical, which ensure ample and efficient air supply. Owing to the special formation of the tips, the static­ al strength is very good, the structure functions even under mechanical load. The plastic sheets forming the packing according to the invention can be produced simply, quickly and in any desired size, the production technology is adapted to the conventional technology. Further details of the invention are described by way of examples with the aid of drawing, in which: Figure 1: Side view of the plastic sheets forming the packing according to the invention Figure 2: Section A-A of the construction shown in Figure 1 Figure 3: Section B-B of the construction shown in Figure 2 Figure 4: Cross section of ribs in another construc­ tion Figure 5: Cross section of ribs in a further construction Figure 6: Top view of an alternative packing assembled with sheets Fiugre 7: Top view of a further version of the pack­ ing. As shown in Figure 1 and 2 sheet 1 is assembled with M-profiles 2, so that shanks 3 join each other along line 5. The jointing lines 5 of M-profiles 2 and centre­ lines 7 at junction of the upper branches 6 are at an angle α to the vertical. In this case α = 5°. Length of the shanks 3 of M-profiles is 25 mm, length of the upper branches 6 is 5 mm. The angle β between shanks 3 is 90°. Shanks 3 of M-profiles 2 are provided with ribbed surface 8. The ribbed surface 8 does not take up the full length of shanks 3, thus flat strips 9 without ribs are in the vicinity of jointing line 5. Its minimum width is 5 mm. Figure 3 shows section B-B of the ribbed surface 8. The ribbed surface is formed by alternately jointed M-profiles 10 and V-profiles 11, so that the M-profiles 10 and V-profiles 11 are turned opposite each other. Height of the M-profiles is 3 mm, the angle γ between the shanks is 60°. Naturally the ribbed surface 8 can be formed differently too, Figure 4 shows a solution with V-profiles turned opposite each other. Figure 5 shows the sectional view of the ribbed surface 8 of a further possible construction, where the profile of the ribs is trapezoid. The sheets 1 can be made of any synthetic foil, e.g. polyethylene, polystyrene polypropylene, polyvinyl­ chloride, hard polyethylene, etc. The packing according to the invention can be produced with sheets 1 in several versions. In the solution shown in Figure 6 sheets 1 are turn­ ed in the same direction, and jointed to each other spaced at half distance of the M-profile. This way the angle between shanks 3 is the same as the angle between upper branches 6, thus shanks 3 or sheets 1 fit into trough 4 formed by the upper branches 6 of the adjacent sheets 1. Channels 12 of square /or in given case rhomboidal/­ cross section are provided in the packing of closed sec­ tion. Only trough 4 formed by upper branches 6 of M-pro­ files 2 is missing from the full square or rhomboidal cross section. The surface per unit volume of the packing of closed section shown in Figure 6 is very large, it may reach even 500 m²/m³. The version shown in Figure 7 also has relati­ vely large specific surface, though its value is lower than that of version shown in Figure 6. Here sheets 1 are jointed opposite each other, so that the sheets of M-profiles end in a point of junction in the hori­ zontal section. Since in this case the jointing lines 5 and centrelines 7 on the sheets 1 are opposite each other, no closed section exists in this version. The specific surface of packings assembled with sheets as shown in Figure 6 or 7 is several times larger than that of the conventional solution, and the relatively narrow angle of the sections and chan­ nels to the vertical results partly in high stability and partly in optimal operation. The waste water is intensively purified on both sides of the sheets under varying or impulsive surface load, consequently the construction is flexible against change of the surface load. Flow velocity of the water on the sheets is controlled by ribbed surface 8. This surface facilitates adhesion of the biological film and increases the specific surface. Thus the packing according to the invention increases the efficiency of the biological drip bodies, while the amount of charge is reduced by 30-40 % and the cost of production and operation by about 40-50 %. Although only one of the possible version is des­ cribed in the example, obviously several other version can be produced based on similar principle. Variable are the sizes and shapes of M and V-profiles. The corrugated surface may differ from the illustrated one, and the tips at joint of the profiles, or within the profiles may be rounded. All these do not change the essential characteristic of the invention, namely the stable assembly and disassembly of the sheets without the use of adhesive, at the same time the cost of pro­ duction and operation is reduced, while the efficiency is increased. Throughout this description and claims, the phase ' M-profile' is intended to cover also 'W-profile' since the question of whether a profile is M-shaped or W-shaped is merely a question of spatial orientation.

Claims: 1. Packing for biological treatment of fluids, comprising a series of plates provided with convex and concave ribs, wherein inclined channels with corrugated side-wall are formed between the ad­ jacent sheets at an angle to the vertical, cha­ racterized in that the sheets /1/ are formed with M-profiles /2/, the jointing lines /5/ and centrelines /7/ of the M-profiles /2/ are unbroken in the full height of the packing and are at maximum 30° /α/ to the vertical, furthermore the corrugated parts are formed as ribbed surface /8/ only on the shanks /3/ of the M-profiles /2/, so that flat strip /9/ without ribs is on both sides of the jointing lines /5/ of the profiles. 2. Packing as claimed in claim 1, charac­ terized in that the sheets /1/ are jointed to each other without the use of adhesive. 3. Packing as claimed in claim 1 or 2, cha­ racterized in that the M-profiles /2/ are formed by flat surfaces. 4. Packing as claimed in claim 1 or 2, cha­ racterized in that the M-profiles /2/ are formed at least in part by curved surfaces. 5. Packing as claimed in any of claims 1 to 4, characterized in that jointing lines /5/ and centrelines /7/ of the M-profiles /2/ are at an angle /α/ of substantially 5° to the vertical. 6. Packing as claimed in any of claims 1 to 5, characterized in that the ribbed surface is formed by flat sheets, where the jointing lines and centrelines of the profiles are horizontal. 7. Packing as claimed in claim 6, charac­ terized in that the ribbed surface /8/ is formed by M or V-profiles. 8. Packing as claimed in any of claims 1 to 7, characterized in that profiles /2,10,11/ are rounded at the tips and joints of the shanks. 9. Packing as claimed in any preceding claim, characterized in that sheets (1) are turned in the same direction, jointed to each other and spaced at a distance of 1/2 M-profile, so that shanks (3) of M-profiles (2) on one of the sheets (1) lie in trough (4) on the upper part of the M-profiles (2) on the adjacent sheet (1). 10. Packing as claimed in any preceding claim, characterized in that sheets (1) are jointed opposite each other, so that shanks (3) of M-profiles (2) end in a point of junction in the horizontal section. 11. Packing as claimed in any preceding claim, characterized in that the tips and shanks (3) of the M-profiles (2) are at an angle (β) of 0-178°, preferably substantially 90° to each other. 12. Packing as claimed in claim 11, characterized in that length of the upper branches (6) of M-profiles (2) is 1-200 mm, preferably substantially 2 mm. 13. Packing as claimed in any preceding claim, characterized in that length of the shanks (3) of M-profiles (2) is 10-200 mm, preferably substantially 25 mm. 14. Packing as claimed in any preceding claim, characterized in that width of the flat strips (9) on shanks (3) of the M-profiles (2) is 1-200 mm, preferably substantially 3 mm. 15. Packing as claimed in any preceding claim, characterized in that height of the M and/or V-profiles (10,11) forming the ribbed surface (8) is 2-16 mm, preferably substantially 5 mm. 16. Packing as claimed in claim 15, characterized in that the angle (γ) between the shanks of M-profiles (10) is 0-178°, preferably substantially 60°. 17. Packing as claimed in any preceding claim, characterized in that length and width of the sheets (1) is 500-3000 mm. 18. Packing as claimed in claim 17, characterized in that size of the sheets (1) is substantially 500x1000 mm.

Inventors: NADUDVARI, JOZSEF, RAGACS, LASZLO
Applicants: H-PANNONPLAST MUEANYAGIPARI VALLALAT
Application year: 1985
Main classification: C02F3
IPC codes: C02F3