HRP920594A2

HRP920594A2 - A filter device

Info

Publication number: HRP920594A2
Application number: HR920594A
Authority: HR
Inventors: James Roxby Simpson; Martin Robiliard Tucker
Original assignee: Biofil Ltd
Priority date: 1989-09-25
Filing date: 1992-09-29
Publication date: 1995-08-31

Description

Sadašnji izum je filtar uređaj za pročišćavanje vode kako bi se ona učinila pitkom i naročito je dragocjen u hitnim situacijama kada je potrebna mikrobiološki sigurna voda s minimalnim odlaganjem i kada dezinfekcijska sredstva nisu lako ili stalno pristupačna, niti su prihvatljiva. The present invention is a filter device for purifying water to make it potable and is particularly valuable in emergency situations where microbiologically safe water with minimal disposal is required and disinfectants are not readily or consistently available or acceptable.

Skoro svi pogoni za pročišćavanje vode uključuju kao suštinsku karakteristiku filtraciju pristupačne vode kroz pijesak. Opisana su dva glavna tipa postupka za filtriranje kroz pijesak i to su sporo i brzo filtriranje kroz pijesak, pri čemu imena odražavaju relativne brzine protoka vodene tekućine kroz sredinu za filtriranje. Međutim, ova dva tipa postupka za filtriranje kroz pijesak također se karakteriziraju temeljnim razlikama u radnom postupku. Almost all water treatment plants include as an essential characteristic the filtration of accessible water through sand. Two main types of sand filtration processes have been described and are slow and rapid sand filtration, the names reflecting the relative flow rates of the aqueous fluid through the filter media. However, these two types of sand filtration processes are also characterized by fundamental differences in operating procedures.

U slučaju brzih pješčanih filtara voda se pročišćuje tako da se zgrušavaju fino raspršene i razmuljene nečistoće (uključujući mnoge prisutne štetne organizme) u tankovima za flokulaciju, poslije čega se veliki djelići koji su formirani zgrušavanjem odvajaju u tankove za slijeganje. Predčišćenje vode na ovaj način omogućava sprovođenje filtracije kroz pijesak sa većom brzinom protoka. U slučaju sporih pješčanih filtara ne vrši se takvo predčišćeje. In the case of rapid sand filters, water is purified by coagulation of finely dispersed and slurried impurities (including many harmful organisms present) in flocculation tanks, after which the large particles formed by coagulation are separated into settling tanks. Water pre-cleaning in this way enables filtration through sand with a higher flow rate. In the case of slow sand filters, no such pre-cleaning is performed.

U sporim pješčanim filtrima, odvajanje nečistoća i naročito štetnih mikroorganizama, vrši se ne samo pomoću fizičkih prepreka u gornjim slojevima pješčanih zrna, već također i uklapanjem nečistoće pomoću mikroorganizama koji se razvijaju u gornjem sloju pijeska; ovaj je obično poznat kao “Schmutzdecke” sloj kojem na početku može biti potrebno za razvijanje nekoliko tjedana i koji u sporim pješčanim filtrima igra ključnu ulogu u proizvodnji vode visoke kvalitete. In slow sand filters, the separation of impurities and especially harmful microorganisms is carried out not only by means of physical obstacles in the upper layers of sand grains, but also by the incorporation of impurities by means of microorganisms that develop in the upper layer of sand; this is commonly known as the “Schmutzdecke” layer which may initially take several weeks to develop and which in slow sand filters plays a key role in producing high quality water.

U hitnoj situaciji kada treba pročišćavanjem stvoriti rezerve sigurne pitke vode i kada izvori sredstava za kemijsko pročišćavanje, kao što su dezinfekcijska sredstva, nisu lako pristupačni, korištenje spornog pješčanog filtra za ovu svrhu bilo bi u načelu poželjno. Međutim, stvaranje potrebnog “Schmutzdecke” sloja traje suviše dugo, pa su spori pješčani filtri do sada bili potpuno nepodesni za korištenje u hitnoj situaciji. In an emergency situation where reserves of safe drinking water need to be created through purification and when sources of chemical purification agents, such as disinfectants, are not easily accessible, the use of the controversial sand filter for this purpose would in principle be desirable. However, the creation of the necessary "Schmutzdecke" layer takes too long, so slow sand filters have so far been completely unsuitable for use in an emergency situation.

Nasuprot ovome stanju, cilj sadašnjeg izuma je osiguranje filtar uređaja koji je dragocjen u hitnim i drugim situacijama i koji se može koristiti za stvaranje rezervi sigurne vode za nekoliko sati. Against this condition, the object of the present invention is to provide a filter device which is valuable in emergency and other situations and which can be used to create a reserve of safe water for several hours.

Filtar uređaj prema sadašnjem izumu obuhvaća gram-negativne bakterije koje proizvode egzo-polisaharid koji je podržan na materijalu koji propušta vodu i koji je netoksičan za mikroorganizme i za ljudska bića, otporan je na temperature u intervalu od -15º C do +65º C i ne može se lako biodegradirati. Ovaj novi filtar uređaj, koji se može koristiti kao zamjena u sporom pješčanom filtru za “Schmutzdecke” sloj, pristupačan je za proizvodnju pitke vode u nekoliko puta kraćem vremenu nego što bi bilo potrebno za stvaranje uobičajenog “Schmutzdecke” sloja. The filter device according to the present invention comprises gram-negative bacteria that produce an exo-polysaccharide supported on a water-permeable material that is non-toxic to microorganisms and human beings, resistant to temperatures in the range from -15º C to +65º C and does not it can easily biodegrade. This new filter device, which can be used as a replacement in a slow sand filter for a "Schmutzdecke" layer, is affordable for the production of drinking water in several times less time than it would take to create a conventional "Schmutzdecke" layer.

U jednom poželjnom obliku filtar uređaj prema sadašnjem izumu, smrzne se do suhog stanja nakon što su primijenjene bakterije na materijal koji propušta vodu. Suho smrznuti proizvod se tada može pakirati u vakuumu tako da se isključi vlažnost i skladišti se sve dok se ne treba koristit. Kad se javi hitna situacija u kojoj je potrebna pitka voda, proizvod se može reaktivirati za nekoliko sati dodavanjem vode i tada se koristi, podesno podržan za pročišćavanje pristupačne vode na način sporog pješčanog filtra. In one preferred form, the filter device of the present invention freezes to a dry state after the bacteria have been applied to the permeable material. The freeze-dried product can then be vacuum packed to exclude moisture and stored until it is needed. When an emergency situation arises where potable water is needed, the product can be reactivated in a few hours by adding water and then used, conveniently supported to purify accessible water in the manner of a slow sand filter.

Gram-negativne bakterije koje proizvode egzo-polisaharid koji se koristi u filtar uređaju iz izuma, su tipa koji se nalazi u “Schmutzdecke” slojevima; tj. one se javljaju prirodno u sloju biofilma standardnog pješčanog filtra za vodu, naročito u području unutar 5 cm, specifičnije 7.5 cm, od površine podloge filtra. Takve prirodne bakterije su karakteristično proizvođači obilnih količina polisaharida u obliku viskoznog ili želatinoznog materijala, pod uvjetima sa niskom koncentracijom hranjivih supstanci. Bakterije koje se koriste u sadašnjem izumu mogu biti smjesa bakterija koja se dobiva kao takva iz “Schmutzdecke” sloja ili mogu biti čiste kulture pojedinačnih vrsta bakterija koje se koriste pojedinačno ili u smjesama, Među podesnim bakterijama mogu se spomenuti vrste Pseudomonas vesicularis, npr. NCIB 40121; Zoogloea ramigera, npr. ATCC 25935 ili NCIB 10340; Pseudomonas sp., npr. NCTB 11264; Achromobacter georgiopolitanum, npr. ATCC 23203; i ne-patogene Pseudomonas vrste koje proizvode alginat kao što je Pseudomonas mendocina, npr. NCIB 10541. Gram-negative bacteria that produce the exo-polysaccharide used in the filter device of the invention are of the type found in the "Schmutzdecke" layers; i.e. they occur naturally in the biofilm layer of a standard sand water filter, especially in the area within 5 cm, more specifically 7.5 cm, of the surface of the filter substrate. Such natural bacteria are characteristically producers of copious amounts of polysaccharides in the form of viscous or gelatinous material, under conditions with a low concentration of nutrients. The bacteria used in the present invention may be a mixture of bacteria obtained as such from the "Schmutzdecke" layer or may be pure cultures of individual species of bacteria used singly or in mixtures. Suitable bacteria include Pseudomonas vesicularis species, e.g. NCIB 40121; Zoogloea ramigera, eg ATCC 25935 or NCIB 10340; Pseudomonas sp., eg NCTB 11264; Achromobacter georgiopolitanum, eg ATCC 23203; and alginate-producing non-pathogenic Pseudomonas species such as Pseudomonas mendocina, eg NCIB 10541.

Naročito poželjna bakterija za korištenje u filtar uređaju prema sadašnjem izumu je ona koja je dio pretežne mikrobne flore u površini biofilma ustanovljenog konvencionalnog spornog pješčanog filtra i koja je deponirana kao NCIB 40121. Ima slijedeće osobine, naime nepigmentiran brz rast na Podlozi A (vidi niže), obilnu proizvodnju muljevitog polisaharida na Podlozi B (vidi niže) i u tekućoj podlozi i na podlozi koja je očvrsnuta sa 1,5 postotaka agara, nema ili ima vrlo slab rast na standardnim bakteriološkim hranjivim agarnim podlogama pune jačine i nema rast na McCnkey agaru. U prethodnom tekstu i kasnije Podloga A je hranjiva juha koja je proizvod M-Lab Ltd., u koncentraciji 2,5 g/litra, koja sadrži 1,0 g/litra glukoze. Podloga B je hranjiva juha u koncentraciji 2.5 g/litra koja sadrži 10,0 g litra glukoze. A particularly preferred bacterium for use in the filter device of the present invention is one that is part of the predominant microbial flora in the biofilm surface of an established conventional spore sand filter and is deposited as NCIB 40121. It has the following characteristics, namely non-pigmented rapid growth on Substrate A (see below) , abundant production of silty polysaccharide on Medium B (see below) in both liquid medium and medium solidified with 1.5 percent agar, no or very poor growth on full-strength standard bacteriological nutrient agar media, and no growth on McCnkey agar. In the previous text and later, Substrate A is nutrient broth, which is a product of M-Lab Ltd., in a concentration of 2.5 g/liter, containing 1.0 g/liter of glucose. Substrate B is nutrient broth at a concentration of 2.5 g/liter containing 10.0 g of glucose per liter.

Izabrana bakterija ili smjesa bakterija podržana je na materijalu koji propušta vodu gornjih specificiranih karakteristika. Materijal koji se koristi ne treba se lako biodegradirati ali je materijal koji se biodegradira relativno sporo, npr. u toku korištenja uređaja, što tipično može biti recimo od 3 do 6 mjeseci, podesan za ovu svrhu. Poželjno je materijalu otpornom na ultraljubičasto zračenje, omogućiti da se koristi pod uvjetima produžene jake sunčeve svjetlosti. Radi omogućavanja kolonizacije mikroorganizama na njegovoj površini poželjno je da površina materijala ne bude suviše polirana niti glatka. Naravno, izabrani materijal koji propušta vodu treba imati nisku rastopljivost ili mora biti nerastopljiv u vodenim fluidima. The selected bacteria or mixture of bacteria is supported on a water-permeable material of the above specified characteristics. The material used should not biodegrade easily, but a material that biodegrades relatively slowly, for example during the use of the device, which can typically be, say, 3 to 6 months, is suitable for this purpose. It is desirable for the material to be resistant to ultraviolet radiation, to allow it to be used under conditions of prolonged strong sunlight. In order to enable the colonization of microorganisms on its surface, it is preferable that the surface of the material is not too polished or smooth. Of course, the selected water permeable material should have a low solubility or must be insoluble in aqueous fluids.

Materijal koji propušta vodu može uzimati razne oblike, tako npr. može biti krut ili porozan materijal koji se može sabijati kao što je neki prošireni polimerni materijal, ili neki vlaknasti materijal kao što je kokosovo vlakno, ili neka netkana tkanina kao što je neki proizvod sličan papiru, ili neki takav tkani proizvod kao što je pamuk ili neki celulozni materijal. Podesan prošireni materijal je celulozna spužva koja se prodaje pod trgovačkim imenom “Spontex”(kompanije Spontex Ltd.). Kada se koristi fleksibilni materijal ovog tipa, on se može skladištiti i/ili prevesti u valjani i/ili sabijen oblik. Podesan netkani materijal je proizvod koji se prodaje pod trgovačkim imenom “Vilene”, koji se nudi na prodaju kao skrojeni međupovršinski materijal. Tanki pločasti materijali kao što je “Vilene” mogu se koristiti u jednom ili više slojeva, ili u obliku sendviča sa drugim materijalima i služe kao nosač. The water permeable material can take many forms, for example it can be a rigid or porous compressible material such as an expanded polymeric material, or a fibrous material such as coir, or a non-woven fabric such as a similar product paper, or some such woven product such as cotton or some cellulosic material. A suitable expanded material is a cellulose sponge sold under the trade name "Spontex" (Spontex Ltd.). When flexible material of this type is used, it can be stored and/or converted into rolled and/or compressed form. The tailored nonwoven material is a product sold under the trade name "Vilene", which is offered for sale as a tailored interfacing material. Thin plate materials such as "Vilene" can be used in one or more layers, or in the form of a sandwich with other materials and serve as a carrier.

Ako je izabrani materijal koji propušta vodu porozan, on naravno treba imati otvorene pore. Poželjan je prosječan promjer pora od najmanje 10 mikrometara, i prije i poslije impregnacije sa bakterijama. Poželjniji prosječni promjer pora je najmanje 20 mikrometara, naročito reda 50 mikrometara, prije impregnacije. I promjer pore i gustoća pore utječe na brzinu kojom voda koja se treba pročistiti može prolaziti kroz filtar uređaj i ovo treba imati na umu prilikom izbora materijala koji propušta vodu koji se treba koristiti. Sa ovim na umu poželjne su poroznosti 70 do 90 postotaka i više. If the chosen material that lets water through is porous, it should of course have open pores. An average pore diameter of at least 10 micrometers is desirable, both before and after impregnation with bacteria. A more preferred average pore diameter is at least 20 micrometers, especially of the order of 50 micrometers, before impregnation. Both pore diameter and pore density affect the speed at which the water to be purified can pass through the filter device and this should be borne in mind when choosing the permeable material to be used. With this in mind, porosities of 70 to 90 percent and above are desirable.

Ako se filtar uređaj treba zamrznuti do suhog stanja, tada se za tu svrhu mogu koristiti tipični uvjeti za postupke suhog zamrzavanja. Poželjno je impregnirani materijal zamrzavati na temperaturi reda -70ºC ili niže. Kasnije odvajanje vode sublimacijom u vakuumu se poželjno vrši pod vakuumom od 1 tora ili ispod tog pritiska. Poslije zamrzavanja do suhog stanja, impregnirani materijal se zatvori u nekom podesnom materijalu koji je nepropustan za vodenu paru, npr. u nekom sloju sintetičkog polimernog materijala. Kada je suho-zamrznut proizvod kasnije potreban za korištenje, vakuumom zatvarač se razbije i doda se voda, i rezultat je da se mikroorganizmi za nekoliko sati (npr. 6 do 8 sati) reaktiviraju i spremni su za korištenje. Za promociju reaktivacije i rasta suho-zamrznutih mikroorganizama, mogu se inkorporitati hranjivi sastojci za mikrobe u impregnirani materijal prije faze suhog zamrzavanja, ili se mogu dodati u vodu koja se koristi za reaktivaciju. If the filter device is to be freeze-dried, then typical conditions for freeze-dry procedures can be used for this purpose. It is preferable to freeze the impregnated material at a temperature of -70ºC or lower. Later separation of water by vacuum sublimation is preferably carried out under a vacuum of 1 torr or below that pressure. After freezing to a dry state, the impregnated material is sealed in a suitable material that is impermeable to water vapor, for example in a layer of synthetic polymer material. When the freeze-dried product is later needed for use, the vacuum seal is broken and water is added, and the result is that the microorganisms are reactivated in a few hours (eg 6 to 8 hours) and are ready for use. To promote the reactivation and growth of freeze-dried microorganisms, microbial nutrients can be incorporated into the impregnated material prior to the freeze-dry stage, or added to the water used for reactivation.

Za korištenje filtar uređaja prema izumu, on se može staviti u kontakt sa slojem pijeska ili sa drugom nosećom podlogom filtra i tada se voda koja se treba pročistiti provodi kroz uređaj pa tako i kroz noseću podlogu filtra. Npr. uređaj se može postaviti horizontalno na sloj pijeska ili se poveže u vertikalnom položaju za jedan ili više blokova od krute porozne noseće podloge. Podesne jednostavne strukture za ovu svrhu prikazane su na prirodnim crtežima, na kojima: To use the filter device according to the invention, it can be placed in contact with a layer of sand or with another support substrate of the filter and then the water to be purified is passed through the device and thus through the support substrate of the filter. For example the device can be placed horizontally on a layer of sand or connected in a vertical position to one or more blocks of rigid porous supporting substrate. Suitable simple structures for this purpose are shown in natural drawings, in which:

Sl. 1 je vertikalni izgled poprečnog presjeka prvog oblika filtar jedinice; Sl. 1 is a vertical cross-sectional view of the first form of filter unit;

Sl. 2 je izgled u ravnini koji odgovara Sl. 1; Sl. 2 is a plan view corresponding to FIG. 1;

Sl. 3 je vertikalni izgled poprečnog presjeka drugog oblika filtar jedinice; i Sl. 3 is a vertical cross-sectional view of another form of filter unit; and

Sl. 4 je izgled u ravnini koji odgovara Sl. 3. Sl. 4 is a plan view corresponding to FIG. 3.

Filtar jedinica ilustrirana na Slikama 1 i 2 je, kao što je prikazana, kvadratna u ravnini (npr. kvadrat od približno 1 metra) i donekle je više od svoje širine (recimo oko 1,5 metra). Formirana je od zarubljenih ravnih dijelova spremišta napravljenog od staklom ojačanog plastičnog materijala, sklopljenog u položaju da se može lakše transportirati, na noseću stepenastu ploču 10. U donjem dijelu jedinice koji je definiran odjeljcima 11 nalaze se pod-drenaže 12 od šljunka ili sličnog materijala, a iznad pod-drenaža 12 je noseća podloga 13 od pijeska. The filter unit illustrated in Figures 1 and 2 is, as shown, square in plan (eg approximately 1 meter square) and somewhat taller than its width (say about 1.5 meters). It is formed of hemmed flat sections of storage made of glass-reinforced plastic material, folded in a position that it can be transported more easily, on a supporting stepped plate 10. In the lower part of the unit, which is defined by sections 11, there are sub-drainages 12 of gravel or similar material, and above the sub-drainage 12 is a supporting base 13 made of sand.

Filtar uređaj 14 prema izumu u obliku sloja bakterija na fleksibilnom materijalu koji ne propušta vodu podržan je pomoću podloge 13. Rubovi uređaja 14 drže se i zatvore se između prirubnica bočnih odjeljaka 11 i gornjih bočnih odjeljaka 15. Nivo vode 16 u jedinici kontroliran je preljevnim protokom 17. The filter device 14 according to the invention in the form of a layer of bacteria on a flexible impermeable material is supported by a substrate 13. The edges of the device 14 are held and closed between the flanges of the side compartments 11 and the upper side compartments 15. The water level 16 in the unit is controlled by the overflow flow. 17.

Prilikom korištenja jedinice voda za tretiranje uvodi se u gornji dio spremišta 14 i noseću podlogu 13 prema podrenažama 12, pri čemu se pitka voda izvlači kroz izlaznu cijev 19 sa ventilima. Kada se koristi filtar uređaj 14 postaje eventualni blokiran i lako ga je zamijeniti novim. When using the unit, water for treatment is introduced into the upper part of the reservoir 14 and the supporting base 13 towards the sub-drainages 12, whereby drinking water is extracted through the outlet pipe 19 with valves. When the filter device 14 is used, it becomes possibly blocked and it is easy to replace it with a new one.

Jedinica koja je ilustrirana na Slikama 3 i 4 oslanja se na vertikalne filtar panele, kroz koje voda teče u uglavnom vodoravnom pravcu od ulaza 20 prema izlazu 21, pri čemu se nivo vode kontrolira preko prelijeva 22. Sistem za filtraciju sastoji se od filtar uređaja 23 prema izumu, spojenih za rubove blokova 24 od porozne noseće podloge, postavljenih u vertikalnim razmaknutim položajima u vodenom spremištu. The unit illustrated in Figures 3 and 4 relies on vertical filter panels, through which water flows in a mostly horizontal direction from the inlet 20 to the outlet 21, with the water level being controlled via an overflow 22. The filtration system consists of a filter device 23 according to the invention, connected to the edges of the blocks 24 of the porous support base, placed in vertical spaced positions in the water reservoir.

U slučaju jedinice sa Slika 3 i 4, kada filtar uređaj eventualno postane blokiran, on i prateći blok 24 mogu se lako zamijeniti bez potrebe da se cijela jedinica povuče iz upotrebe. In the case of the unit of Figures 3 and 4, when the filter device eventually becomes blocked, it and the accompanying block 24 can be easily replaced without having to take the entire unit out of service.

Prilikom eksperimentalnog korištenja svake ilustrirane jedinice postignuta su visoka odvajanja patogenih mikroorganizama za nekoliko sati od početka reaktivacije podržanih bakterija. During the experimental use of each illustrated unit, high separations of pathogenic microorganisms were achieved within a few hours from the start of the reactivation of the supported bacteria.

Izum je dalje opisan i ilustriran pomoću slijedećih Primjera koji opisuju pravljenje dvije realizacije filtar uređaja prema izumu i korištenje jednog od napravljenih uređaja za pročišćavanje zagađene vode. U oba slučaja korištena bakterija bila je gore opisana naročito poželjna bakterija koja je identificirana kao Depozit No. NCIB 40121. The invention is further described and illustrated by means of the following Examples, which describe the making of two realizations of the filter device according to the invention and the use of one of the made devices for purifying polluted water. In both cases the bacteria used was the particularly preferred bacteria described above and identified as Deposit No. NCIB 40121.

Primjer 1 Example 1

Podloga za održavanje je gore opisana Podloga B učvršćena sa 1.5 postotaka (mas./V) agara. Za dugotrajno skladištenje bakterije koje su rasle na podlozi za održavanje na 30º C tijekom 48 sati, suspendiraju se u Podlozi B koja sadrži (20% mas.V) i skladište na -70º C u bocama s poklopcima sa zavrtnje. U svim slučajevima dodaje se glukoza, sterilizirana posebno autoklaviranjem na 121º C tijekom 15 min., pošto se podloga sterilizira na isti način. The maintenance medium is the above-described Medium B solidified with 1.5 percent (w/v) agar. For long-term storage, bacteria grown on medium maintained at 30º C for 48 hours are suspended in Medium B containing (20% wt.V) and stored at -70º C in screw cap bottles. In all cases, glucose is added, sterilized separately by autoclaving at 121º C for 15 min., since the substrate is sterilized in the same way.

(a) Rast inokulata. (a) Growth of inoculum.

Bakterija koja proizvodi mulj inokulira se iz ploče za održavanje u 50 ml Podloge A u konusnom balonu od 150 ml i inkubira se u miješalici-inkubatoru pri 100 rpm (obrtaja u minuti), na 30º C tijekom 16 sati. Ova kultura se koristi za inokulaciju (2% zapr./zapr.) 50 ml iste podloge, i kultura se inokulira kao gore tijekom 6 sati. Sludge-producing bacteria are inoculated from the maintenance plate into 50 ml of Medium A in a 150 ml conical flask and incubated in a mixer-incubator at 100 rpm, at 30º C for 16 hours. This culture is used to inoculate (2% v/v) 50 ml of the same medium, and the culture is inoculated as above for 6 hours.

(b) Inokulacija materijala koji je propustan za vodu i rast bakterija (b) Inoculation of material that is permeable to water and bacterial growth

Sterilni diskovi promjera 5 cm od celuloznog spužvastog materijala koji se prodaje kao “Spontex” koji je bio ispran u autoklavu sa destiliranom vodom pod pritiskom, inkubiraju se u gornjem inokulatu, pod istim uvjetima tijekom 3 sata. Inokulirani filtar diskovi se prenesu aseptično u 50 ml Podloge B u konusnom balonu kapaciteta 250 ml, i inkubiraju se na 30º C, 100 rpm, u orbitalnom inkubatoru dok se ne uspostavi dovoljno muljevitog biofilma da se osigura otpornost za protok vode tako da je linearna brzina protoka 0,2 m/sat kroz filtar pod hidrostatičkim tlakom od 10 cm. Tipično vrijeme inkubacije koje je potrebno za postizanje ove količine biofilma je između 8 i 16 sati ovisno o početnoj veličini pore nosećeg materijala. Veća veličina pora predviđa duži period inkubacije. Sterile discs with a diameter of 5 cm made of cellulose sponge material sold as "Spontex" that have been washed in an autoclave with distilled water under pressure, are incubated in the above inoculum under the same conditions for 3 hours. The inoculated filter discs are transferred aseptically to 50 ml of Medium B in a 250 ml conical flask, and incubated at 30º C, 100 rpm, in an orbital incubator until sufficient silty biofilm is established to provide resistance to water flow such that the linear rate flow rate of 0.2 m/hour through the filter under a hydrostatic pressure of 10 cm. The typical incubation time required to achieve this amount of biofilm is between 8 and 16 hours depending on the initial pore size of the support material. A larger pore size predicts a longer incubation period.

Primjer 2 Example 2

Koristi se postupak koji je opisan u Primjeru 1 da se uspostave biofilmovi u obliku slojeva od diskova promjera 5 cm i debljine 1 do 2 cm od netkane tkanine koja se prodaje pod trgovačkim imenom “Vilene”. Podesan biofilm formira se poslije 8 sati inkubacije. The procedure described in Example 1 is used to establish biofilms in the form of layers of discs 5 cm in diameter and 1 to 2 cm thick of a non-woven fabric sold under the trade name "Vilene". A suitable biofilm is formed after 8 hours of incubation.

Primjer 3 Example 3

Pomoću istog postupka koji se koristi u Primjerima 1 i 2, formira se biofilm u obliku diskova promjera 5 cm koji obuhvaćaju 10 cm debeo sloj od materijala od kokosovih vlakana ojačanog plastičnom mrežom. Finalno vrijeme inkubacije bilo je 16 sati. Using the same procedure used in Examples 1 and 2, a biofilm is formed in the form of 5 cm diameter discs enclosing a 10 cm thick layer of coconut fiber material reinforced with plastic mesh. The final incubation time was 16 hours.

Primjer 4 Laboratorijsko mjerenje karakteristika filtra Example 4 Laboratory measurement of filter characteristics

Karakteristike se procijene korištenjem diskova impregniranih biofilmom promjera 5 cm kao što su napravljeni u Primjerima 1 do 3 u standardnim laboratorijskim držačima filtra sa potpornim sitima od plastične mreže, pod hidrostatičkom glavom od 10 cm. Koriste se dva tipa vode koja se testira (a) fekalna prirodna voda koja je zagađena koliform organizmima, a to je tipično voda koja dolazi u gradske pogone za pročišćavanje vode; (b) fosfatna puferska slana otopina koja sadrži laboratorijsku vrstu Escherichia coli koja nosi gen rezistentnosti na nalidiks kiselinu između 10.000 i 20.000 bakterija/100 ml). Odbrojavanje koliform bakterija (koristi se kao mjera kvalitete vode) mejri se u obadvije vode standardnim međunarodnim postupcima (uglavnom korištenje selektivne podloge - McConkey podloge - u testovima u epruvetama i standardni kvantitativni testovi za E.coli). Bakterije koje su rezistentne na Nalidiksinsku kiselinu se odbrojavaju navlačenjem uzoraka vode od 0.1 ml na pločama sa hranjivim agarom (M-lab Ltd.) koji sadrže 10 mg/ml nalidiksinkse kiseline. The characteristics are evaluated using 5 cm diameter biofilm-impregnated discs as made in Examples 1 to 3 in standard laboratory filter holders with plastic mesh support screens, under a 10 cm hydrostatic head. Two types of water are used to be tested (a) faecal natural water that is contaminated with coliform organisms, which is typically water that comes to city water treatment plants; (b) phosphate buffered saline containing a laboratory strain of Escherichia coli carrying the nalidixic acid resistance gene between 10,000 and 20,000 bacteria/100 ml). The count of coliform bacteria (used as a measure of water quality) is measured in both waters by standard international procedures (mainly the use of a selective medium - McConkey medium - in test tubes and standard quantitative tests for E.coli). Nalidixic acid-resistant bacteria are counted by streaking 0.1 ml water samples on nutrient agar plates (M-lab Ltd.) containing 10 mg/ml nalidixic acid.

Izlazna voda sa filtara procjenjuje se na kontaminaciju koliformom kao što je opisano gore u sukcesicnim partijama filtrata od po 200 ml. Tipično se odbrojavanje koliforma smanjuje na manje od 10 bakterija na 100 ml u drugoj seriji filtrata od 200 ml i ostaje ispod ovog nivoa u kasnijim serijama od 200 ml. The outlet water from the filters is assessed for coliform contamination as described above in successive batches of 200 ml filtrate. Typically, the coliform count decreases to less than 10 bacteria per 100 ml in the second 200 ml batch of filtrate and remains below this level in subsequent 200 ml batches.

Primjer 5 Proizvodnja u velikim laboratorijskim razmjerima Example 5 Production on a large laboratory scale

Za noseći materijal koji propušta vodu koristi se kvadratna ploča od 1 metra od celulozne spužve koja se prodaje pod trgovačkim imenom “Spontex”, od 15 do 20 mm debljine. Ova ploča se ispere u destiliranoj vodi autoklaviranjem na 121º C tijekom 1 sata i kasnijim cijeđenjem do suhog stanja. Ploča se potpuno uroni u Podlozi A u laboratorijskom fermentoru i sterilizira se sa podlogom in-situ. Glukoza se sterilizira posebno kao u Primjeru 1 i doda se aseptično. Temperatura fermentora uravnotežuje se na 30º C i doda se 5% (po zapremnini) inokulat bakterije kulture, napravljen kao za inokulat u Primjeru 1. Fermentor se propuhuje zrakom brzinom od 1 litra zraka/min/litra podloge za kulturu i miješa se pri 200 rpm. Poslije 8 sati, doda se sterilna glukoza (40% mas./V) tako da se dobije finalna koncentracija 10g/litra i inkubacija se nastavlja pod istim uvjetima tijekom daljnjeg perioda između 16 i 24 sati; nivoi rastvorenog kisika se ne kontroliraju. A 1-meter square board made of cellulose sponge sold under the trade name "Spontex", 15 to 20 mm thick, is used for the water-permeable carrier material. This plate is washed in distilled water by autoclaving at 121º C for 1 hour and later squeezing to dryness. The plate is completely immersed in Medium A in a laboratory fermenter and sterilized with the medium in-situ. Glucose is sterilized separately as in Example 1 and added aseptically. The temperature of the fermenter is equilibrated to 30º C and a 5% (by volume) inoculum of culture bacteria is added, made as for the inoculum in Example 1. The fermenter is blown with air at a rate of 1 liter of air/min/liter of culture medium and mixed at 200 rpm . After 8 hours, sterile glucose (40% wt./V) is added so that a final concentration of 10g/liter is obtained and the incubation continues under the same conditions for a further period between 16 and 24 hours; dissolved oxygen levels are not controlled.

Dobivena impregnirana ploča podesna je za korištenje u nekoj filtar jedinici kao što je jedna od dva tipa koja su prikazana na pratećim crtežima. The resulting impregnated board is suitable for use in a filter unit such as one of the two types shown in the accompanying drawings.

Poželjan materijal iz kojeg se formira sloj koji propušta vodu je celulozna spužva kao što je ovdje opisan. Međutim, mogu se koristiti drugi materijali, pod uvjetom da zadovoljavaju glavne zahtjeve koji su: (a) propustljivost za vodu; (b) netoksičnost za mikroorganizme i ljudska bića; (c) rezistentnost na temperature u intervalu od -15º C do +65º C; i (d) da se ne može lako biodegradirati. A preferred material from which the water permeable layer is formed is a cellulose sponge as described herein. However, other materials may be used, provided they meet the main requirements which are: (a) water permeability; (b) non-toxic to microorganisms and human beings; (c) resistance to temperatures in the interval from -15º C to +65º C; and (d) not readily biodegradable.

Dalje, materijali koji se mogu koristiti u filtar uređaju iz izuma, za podržavanje gram-negativnih bakterija koje proizvode egzopolisaharad, mogu biti samonoseći ili nošeni na ili u nekom podesnom nosaču. Primjeri ovih daljnjih materijala uključuju pijesak i šljunak, žičanu vunu od nehrđajućeg čelika, sintetizirano staklo, vermikulit, perlit i strugotinu ili odreske od tvrdog drveta. Further, the materials that can be used in the filter device of the invention, for supporting gram-negative exopolysaccharide-producing bacteria, can be self-supporting or carried on or in some suitable support. Examples of these additional materials include sand and gravel, stainless steel wire wool, synthetic glass, vermiculite, perlite, and hardwood shavings or chips.

Claims

1. A filter device for water purification, characterized by the fact that it includes gram-negative bacteria that produce exo-polysaccharide supported on a material that is permeable to water, is non-toxic to microorganisms and human beings, is resistant to temperatures in the range of -15º C to +65º C and cannot be easily biodegraded.

2. A filter device according to Claim 1, characterized in that the bacteria are of the type that occurs in nature in the biofilm layer of a slow sand water filter.

3. A filter device according to Claim 1, characterized in that the bacteria are one or more of the bacteria identified by Deposit Numbers NCIB 40121, ATCC 25935, NCIB 10340, NCUB 11264, ATCC 23203 and NCIB 10541.

4. A filter device according to any one of the preceding Claims, characterized in that the water-permeable material is a solid or porous compressible material.

5. A filter device according to Claim 4 and Claim 5, characterized in that the water-permeable material is cellulose sponge.

6. A filter device according to Claim 4 and Claim 5, characterized in that the water-permeable material has an average pore size of at least 20 micrometers.

7. A filter device according to any one of Claims 4 to 6, characterized in that the water-permeable material has a porosity of at least 70 percent.

8. A filter device according to any one of Claims 1 to 3, characterized in that the water-permeable material is a fibrous material.

9. Filter device according to Claim 8, characterized in that the fibrous material comprises coconut fibers.

10. A filter device according to Claim 4 and Claim 5, characterized in that the water-permeable material is a non-woven or woven fabric.

11. A filter device according to any one of the preceding claims, characterized in that it is frozen from the dry state after the bacteria have been applied to the water-permeable material.

12. A filter device according to any one of Claims 1 to 3, 5, 7 or 11, characterized in that the water-permeable material comprises sand/gravel, stainless steel wire mesh, synthetic glass, vermiculite, perlite, or hardwood shavings or chips. wood.