Classifications

• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F3/00—Biological treatment of water, waste water, or sewage
  • C02F3/34—Biological treatment of water, waste water, or sewage characterised by the microorganisms used
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F3/00—Biological treatment of water, waste water, or sewage
  • C02F3/006—Regulation methods for biological treatment
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F3/00—Biological treatment of water, waste water, or sewage
  • C02F3/34—Biological treatment of water, waste water, or sewage characterised by the microorganisms used
  • C02F3/348—Biological treatment of water, waste water, or sewage characterised by the microorganisms used characterised by the way or the form in which the microorganisms are added or dosed
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F1/00—Treatment of water, waste water, or sewage
  • C02F1/72—Treatment of water, waste water, or sewage by oxidation
  • C02F1/722—Oxidation by peroxides
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F11/00—Treatment of sludge; Devices therefor
  • C02F11/02—Biological treatment
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F2209/00—Controlling or monitoring parameters in water treatment
  • C02F2209/02—Temperature
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F2209/00—Controlling or monitoring parameters in water treatment
  • C02F2209/06—Controlling or monitoring parameters in water treatment pH
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F2209/00—Controlling or monitoring parameters in water treatment
  • C02F2209/40—Liquid flow rate
• • C—CHEMISTRY; METALLURGY
  • C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
  • C02F3/00—Biological treatment of water, waste water, or sewage
  • C02F3/02—Aerobic processes
  • C02F3/12—Activated sludge processes
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
  • Y02W10/00—Technologies for wastewater treatment
  • Y02W10/10—Biological treatment of water, waste water, or sewage
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
  • Y02W10/00—Technologies for wastewater treatment
  • Y02W10/20—Sludge processing

Definitions

• the invention relates to a biological treatment method for the reduction of sewage sludge and an installation using such a method. More specifically, the field considered is the treatment of urban wastewater.
• This process is particularly intended for the treatment of sludge resulting from the treatment of such effluents predominantly "urban” and whose regulated spreading 10 requires treatment solutions without transfer of the pollution problem and in the context of respect for ecosystems.
• the 20 seeks to promote catabolism of endogenous microorganisms. This can be achieved by changing the age of the sludge or by coupling processes combining cell lysis with aerobic (CO 2 ) or anaerobic (CH) biological treatment.
• CO 2 aerobic
• CH anaerobic
• Part of bacteria such as Pseudomonas, whose life cycle leads to the conversion of a fraction of the organic carbon of the sludge into gas (CO2 or methane).
• CO2 or methane gas
• the process is controlled by a minimal but long enough sludge residence time.
• thermophilic anaerobic treatments give better results than aerobic treatments but require complex installations.
• the invention aims to overcome the disadvantages of the prior art.
• the invention aims in particular to degrade a larger fraction of the organic matter of the sludge in a range of 20 to 40% on average of the amount of dry matter (organic matter and mineral matter) sludge, to reduce as much the volume.
• the invention may also aim to further control the rate of this degradation, to optimize the effluent treatment rate according to the upstream and downstream constraints of the installation.
• the invention also aims at a global saving of the operating costs of a treatment and purification station STEP, the expenses of elimination of residual sludge being increasing.
• the subject of the invention is, according to a first aspect, a method for treating sludge of an urban treatment plant, comprising a step of treating the sludge with micromycetes.
• micromycetes reference is made to microorganisms, as opposed to higher fungi.
• mycelium which is the vegetative apparatus, and the spores.
• any lower mushroom used in sufficient quantity to contribute to the degradation of the sludge, is understood to mean this degradation being evaluated by appropriate techniques within the scope of those skilled in the art.
• the species mentioned below are to be considered as non-limiting examples, the invention covering the use of species whose sludge degradation activity is demonstrated.
• micromycete or mycelium will be used indifferently for the sake of simplicity.
• micromycetes that are effective in degrading sludge, some species can be found in sewage sludge. We speak of endogenous micromycetes. But these micromycetes are present in insufficient quantities in these sludges to degrade them sufficiently. And they are not implanted under conditions favoring the mode of metabolism sought for optimal degradation of the material.
• the process comprises, in parallel with the treatment of sludge by micromycetes, the continuous culture of micromycetes.
• the sludge treatment time by micromycetes is typically between 1 and 10 days, typically between 2 and 5 days.
• the flows of mycelium and sludge to be treated are regulated in the installation accordingly. It is typically carried out at pH of the order of 5.5 to 9, at a temperature between 10 and
• a single strain of micromycetes is used. According to another embodiment, several different strains are combined, forming a mycelial mixture, possibly with a synergistic effect.
• the micromycetes are chosen from the genera PENICILLIUM, TRICHODERMA, PHOMA, MUCOR, FUSARIUM.
• GALACTOMYCES GALACTOMYCES, ASPERGILLUS, BOTRYTIS, GEOMYCES and their mixtures.
• PENICILLIUM roqueforti PENICILLIUM camembertii
• PENICILLIUM chrysogenum notatum, meleagrinum, flavidomarginatum, rubens, chlorophaeum, camerunense, aromaticum, harmonense
• PENICILLIUM atramentosum TRICHODERMA viride
• TRICHODERMA Koningii TRICHODERMA reesei
• MUCOR hiemalis MUCOR mucedo
• MUCOR racemosus MUCOR circinelloids
• MUCOR fuscus MUCOR circinelloides.
• other selected non-mycelial microorganisms may be optionally associated with the mycelial component to live in synergy and develop the same functions.
• These microorganisms include bacteria, yeasts, protozoa, amoebae.
• yeasts it will be possible to use Saccharomyces yeasts.
• bacteria it will be possible to use bacteria of the genus Bacillus, and in particular alicyclobacillus, paenibacillus, brevibacillus, aneurinibacillus, virgibacillus.
• Bacillus can be used in particular: subtilis, anthracis, cereus, licheniformis, megaterium, pumilus, sphaericus, thuringiensis.
• thermophilic bacteria may be used in particular: bacillus stearothermophilus, bacillus thermoglucosidasius, bacillus thermodenitrificans.
• Halobacillus bacteria such as sporosarcina halophila may also be used.
• micromycetes will be associated with at least one other microorganism producing an antibiotic agent.
• the Applicant has indeed found, surprisingly, the synergistic effect on sludge degradation obtained by the combined use of antibiotic agents and micromycetes.
• Antibiotic agents can be produced in situ or added before or at the same time as micromycetes.
• Such antibiotic agents may be provided by certain species such as Penicillium (in particular C ⁇ sogenum) and Aspergillus, Paecilomyces.
• the proposed interpretation lies in the inhibitory effect of bacterial activity by antibiotics in favor of the functioning of the mycelial population, which allows to promote the degradation of the material.
• Mycelial metabolisms are thus reinforced with respect to bacterial metabolism in the mycelial digestion tank (contact basin described below).
• Other antibiotic-producing species such as streptomyces, may also be used.
• the antibiotic molecules are typically enzymes, and / or protein molecules, cyclic compounds, fuscidic acids. According to embodiments, such species capable of generating antibiotic molecules that make it possible to promote the implantation of exogenous biomass at the expense of endogenous biomass, only at the start-up phase or punctually in the year of use, are used. . Indeed, these species help the mycelial species to establish themselves, which makes it possible to optimize the degradation process of the organic matter.
• antibiotic agent producing species are used to promote the implantation of mycelial species into the bioreactor to avoid contamination of the bioreactor.
• the micromycetes will be associated with oxidizing agents.
• the Applicant has in fact surprisingly found the synergistic effect on sludge degradation, the combined use of oxidizing agents and micromycetes.
• the process will then comprise a sludge treatment step with at least one oxidizing agent, injected in line or in a pretreatment tank.
• This oxidizing treatment precedes the biological treatment with micromycetes, and has a duration typically less than three hours, preferably of the order of 30 minutes.
• the oxidizing agent comprises H 2 O 2 and ferric or ferric salts.
• the Fenton reagent or the like is preferred.
• other oxidants can be used such as COMPLETE
• the use of such an oxidizing agent makes it possible to unbalance the populations present in the sludge and in the mycelial digestion tank in favor of the mycelial species, which allows to increase their work of degradation of the material.
• the Applicant has in fact demonstrated that at a given dosage of Fenton reagent (calculated as a function of the concentration of sludge expressed in MES g / 1), a pre-degrading reaction of the material generates an easier accessibility to the substrate for the mycelial species present in our cocktail.
• the use of Fenton's reagent increases on average by 5 to 30% (sometimes more depending on the initial qualities of sludge) the degradation yield of organic matter compared to the use of only micromycetes.
• Ferrous salts or ferric salts may be used.
• the reagent is typically used at temperatures in the range of 10 to 40 ° C.
• the amount of reagent will be controlled in order to avoid an excessive rise in temperature during the oxidative treatment.
• the pH of the sludge treated with the Fenton reagent is typically in the range of 5 to 8, preferably in the range of 5.5 to 6.5.
• the Applicant has demonstrated that the Fenton reagent used alone on sludge not added to the mycelial cocktail after the oxidizing treatment has no effect at the natural pH and under the conditions of treatment.
• the proposed interpretation of the surprising synergistic effect found is, from a microbiological point of view, an inhibition of partial or total bacterial metabolism, depending on the case, by the oxidant used, which creates a differential used by the mycelial species which have access to the substrate much more easily and freely.
• the culture of micromycetes is aerobic, and is continuously in a bioreactor.
• the sludge is treated continuously.
• the rate of treatment is a function of the sludge concentration of the MS and the pollutant load. It is estimated per 1000 eq.hab (with consideration of an MS / DBO5 ratio of 0.8 to 1, this parameter varying according to the type of wastewater to be treated) a variation in flow rate of order of 2 to 10 m3 / day / 1000 eq.hab.
• micromycetes are injected at a rate of the order of 0.01 to 10% of the volume of sludge to be treated per day, typically of the order of 2 to 5%. As will be seen, they are administered in the form of a culture in a liquid medium.
• the micromycetes are injected at a volume of 0.01 to 15%, typically of the order of 2 to 10% of the volume of sludge to be treated per day. .
• the amount of dry matter sludge treated with micromycetes is reduced to about 10 to 50%, typically of the order of 20 to 30%, compared to that of untreated sludge. Depending on the setting parameters this degradation may be greater.
• the micromycete treatment method comprises a simultaneous membrane filtration step of the sludge (effluents) treated with micromycetes.
• the invention relates to a water treatment process in an urban treatment plant, comprising the following successive stages:
• the invention relates to a water treatment process in an urban treatment plant, comprising the following successive stages:
• the invention relates to an effluent treatment plant of predominantly urban wastewater treatment plant intended to implement such a process, comprising: a first treatment tank comprising sewage sludge, downstream of the first treatment tank, at least one biological contact basin intended for the degradation of at least a portion of the sludge by the micromycetes,
• the invention relates to an urban treatment treatment plant effluent treatment plant, intended to implement a process combining treatment with micromycetes and membrane treatment, comprising: a mixed treatment tank comprising effluents; treatment plant for the degradation of at least a part of the sludge (effluents) by the micromycetes, the mixed treatment tank comprising a membrane filtration system, - in parallel with the mixed treatment tank, a bioreactor of continuous culture of micromycetes,
• the bioreactor comprises:
• this comprises means of arrival of the micromycetes, means of arrival of the sludge, stirring means, aeration means, means for evacuation of sludge treated, and preferably means for regulating the flow of arrival and output sludge and micromycetes, pH and temperature.
• the contact basin has a capacity adapted to the installation.
• the capacity is in particular a function of the residence time of the sludge to be treated.
• the volume of the contact basin varies from 10 to 40 m3 per 1000 eq.hab (equivalent inhabitants).
• the treatment can be biological or mixed (chemical and biological agents).
• known species are combined to secrete antibiotic principles used within the contact basin itself in order to inhibit the bacterial population. This requires developing and producing these same species within the bioreactor but also possibly, and in some cases, in a parallel bioreactor. Compound samples of the degradation micromycete cocktail associated with the species that will act as bacterial inhibitors will be prepared.
• Sewage treatment plant sludge consists mainly of biomass. This native biomass is difficult to achieve, and the effect of an oxidant partially degrades these constitutive bacteria of the sludge. These bacteria molecules (destroyed native bacteria) are more accessible substrates for micromycete species.
• the oxidation takes place in a short time of the order of 30 minutes, upstream of the contact basin, which makes it possible not to attack the mycelial species.
• One will use either an injection in line respecting a residence time upstream, or a tank with a residence time on average of 30 minutes with agitation.
• oxidizing reagent for example, use will be made, for example, of an H 2 O 2 storage tank, an iron sultate salt storage tank, and a tank for the preparation of the oxidizing mixture.
• injected dosages of oxidizing reagent will be used directly, using appropriate pumps and regulations.
• it will be possible to choose a treatment only with micromycetes, or a treatment with micromycetes associated with an oxidizing treatment and / or an antibiotic treatment.
• An installation 1 known from the prior art comprises from upstream to downstream:
• the sludge fraction at the outlet of the basin 4 is returned by transfer means 6 to the basin 3 of activated sludge.
• the installation 1 further comprises: a contact basin 8 in which the mycelia are brought into contact with the sludge which comes from the sampling of the recirculated sludge by means of pipe 7, or possibly directly from the pond 3 by driving means 7a
• a mycelium culture bioreactor 9 transferred via a line 10 to the contact basin 8.
• the sludge thus treated by the mycelia is removed from the basin 8 to an area 11 of sludge treatment and storage.
• the sludge undergoes, if necessary, an ultimate treatment or a combination of treatments (dehydration, centrifugation, drying, thermolysis, incineration) of the sludge (or other outlets) in a downstream zone 15.
• the contact basin 8 comprises an air inlet 12.
• the installation comprises a pre-treatment tank 16 upstream of the contact basin (or mycelial digestion tank). 8, therefore positioned either on the sludge supply line 7 or again on the sampling line 7 a.
• each step a single element of the installation. It is understood that the number of each element is likely to be adapted according to the sizing and the type of installation.
• the bioreactor 9 operates according to the principle analogous to the "trickle bed", using an ordered packing medium.
• This bioreactor 9, which could be named “low-volume mycelial bed” in a proportion ranging from 1/100 to 1/50 of the contact basin 8, is used to cultivate the aerated mycelial cocktail after having been selected for each type of mud.
• the size of the bioreactor 9 is dependent on the flow to be treated but also on the quality and / or the composition of the effluents to be treated.
• An appropriate amount of mycelial preparation is transferred via line 10 into contact vat 8.
• the mycelial preparation produced in bioreactor 9 comprises spores and mycelia.
• the volume of sludge treated in the contact basin 8 corresponds to a residence time of several days, it is aerated and inoculated by the spores and mycelium produced in situ, and stirred continuously using an agitator 14.
• the treated sludge is optionally directed from the outlet S of the contact basin 9 via a pipe 17 to an aerated zone 11 in order to prevent any risk of phosphorus release in the case where a biological (or mixed) dephosphatation has been applied. in the upstream die.
• the sizing volume having taken into account a direct discharge into the dehydration system (or any other system) downstream, the pumping of the effluents is done directly without intermediate storage. It should be noted that sizing of the sludge die downstream is reduced due to the reduction of sludge volume, but also optimized by obtaining better drainability of the sludge and better dewaterability.
• the operation of the system can take both forms, continuous or by tarpaulin.
• the method comprises a sludge pumping phase extracted from the activated sludge die in the pond 3, or recirculation 6, to feed the aerobic treatment phase in the contact basin 8.
• This basin 8 is in the form of a structure equipped with ventilation ramps 13 and according to the designs of a stirring system 14.
• the aerobic biodigestion is continuously fed on the one hand by the sludge to be degraded from the basin sludge 3 and secondly by the mycelial mixture which develops independently in the bioreactor 9.
• the sludge also called effluent to be treated
• whose recommended pH varies between 5.5 and 9 feeds this contact basin 8 by pumping with a moderate flow over the recirculation of the sludge of the aeration basin, using a main pump and a backup pump in parallel.
• the filling of the contact basin 8 is thus progressive, continuous and regulated while respecting a residence time in this basin 8 of at most 10 days of the effluent to be treated and at least 24 hours. According to the flows to be treated with taking into account the management of the storage volumes, this duration can be increased, the efficiency of the process will be only slightly favored and the complementary time will not correspond to an economic optimum.
• the contact basin 8 is dimensioned taking into account the residence time and the sludge concentration expressed in MS (g / L): this imposes a overall volume classically equipped with the equipment necessary for its proper functioning. This book is ventilated at the bottom of the pond. Medium bubble type airlift can be selected or any similar system.
• a syncopated homogenization is possibly required according to the periods and the type of effluents to be treated.
• the contact basin 8 contains a substantially constant mycelial population because the connected system of the bioreactor type 9 makes it possible to generate continuous populations with a limited growth rate.
• a simple automation control known to those skilled in the art can act on both aeration and brewing.
• Regulating probes and / or indicating temperature, oxygenation and pH are desirable to verify the good stability of these parameters: pH ranging from 5.5 to 9, temperature from 10 to 30 ° C, slow stirring Oxygenation of 1 to 5 mg / L dissolved oxygen (in some cases this parameter may be increased), residence time approximately 5 days.
• the bioreactor 9 for producing continuous mycelia is now more precisely described. It must be able to provide the microbial biomass that it contains and that develops there, the quantity of oxygen which it needs. It involves mixing three phases: an aqueous phase (the culture medium), a gaseous phase (the gas of oxygenation of the mycelia, typically of air), a biotic phase constituted by the microbial biomass with mycelial majority.
• an aqueous phase the culture medium
• a gaseous phase the gas of oxygenation of the mycelia, typically of air
• a biotic phase constituted by the microbial biomass with mycelial majority.
• the smooth progress of the process is related to the transfer phenomena between the cells (mycelia and spores) and the culture medium. It is first of all a transfer of matter from the external medium to the cell as regards the substrate and the compounds of the culture medium necessary for cell growth, in the opposite direction for the products of the metabolism of the cells in culture. . In order for the transfers to be carried out correctly, the distribution of the cells in the culture medium must be the best possible. In aerobic mycelium culture, it is the oxygenation gas that creates the turbulence and allows the maintaining the cells in homogeneous suspension. The geometry of the bioreactor is designed so that oxygen transfer is as efficient as possible.
• the supply of nutrients makes it possible to promote the development of micromycetes microorganisms and thus has an influence on the kinetic behavior of the microbial population present.
• the bioreactor 9 typically comprises, at the air inlet, an air filtration system designed to prevent contamination by undesired microorganisms, especially yeasts.
• the contact basin 8 is designed according to the type of process that must take place there.
• the bioreactor 9 is designed to allow as good contact as possible between the two biotic and abiotic phases of the system.
• the bioreactor establishes the established regime of the process described. When the established regime is reached (maximum level of sludge reduction performance), the regular supply of a sufficient quantity of sludge (substrate for the flora) makes it possible to maintain the microbial population with a constant degree of performance.
• the effective treatment of the sludge in the contact basin 8 is obtained by using a supply of micromycetes, produced in situ in the bioreactor 9, in the basin 8, and / or a recirculation of sludge having already remained in the contact basin 8.
• the choice depends in particular on the type of effluent to be treated.
• the treatment with micromycetes is carried out with recirculation on the water stream: sludge treated with micromycetes is discharged from outlet S, take line 17 and then line 17a to return to line 6.
• a culture and / or injection system will preferably be used in order to permanently provide a high load of microorganisms.
• This culture is carried out in the bioreactor 9 from selected microbial products (inoculum of strains and its culture medium based on malt extract, starch, etc.) and specific nutrients (source of carbon, nitrogen , etc.) for the amplification of the inoculum.
• repetitive inputs of biocatalysts may be automatically performed during the process.
• sludge loaded with micromycetes application of inoculation on the first day
• micromycete cultures may not be sufficiently specific (uncontrolled development in the presence of nutrients from non-specific and non-repetitive flora) .
• a mixture of a selected "exogenous" fungi and other "endogenous” amplified and nutrient regulated flora will preferably be used.
• the process then makes it possible to constantly overdose the "active ingredient” and maintain the technical performance despite variations in the flow or composition of sludge.
• the bioreactor 9, allowing on-site production and / or continuous injection of microorganisms in the contact basin 8, allows permanent and optimal colonization of the sludge. Compared to the definition of the chemostat mode which involves a single inoculation on the first day and then self-sufficiency, this is an additional security.
• the bioreactor 9 can be in a variety of forms, such as a cylindrical column, of variable height depending on the sizing flows: air, surface of the contact lining. It comprises, for example, three parts: a lower part making it possible to collect a liquid loaded with mycelium, pumped and then poured into the upper part of the column which forms a spraying system (spray boom designed in such a way that the mycelia are not fragmented).
• the central portion contains a structured type of packing or other, to optimize the implantation of the cultivated population, its fixation and development in favorable conditions.
• This packing can be of different types and different materials, the main thing being to allow the attachment of the mycelia.
• This spraying generated by a recirculation of the liquid (via a pump) allows its runoff on the lining of the tower and thus moistens the mycelia that adsorb the components of the liquid.
• This bioreactor 9 with a capacity of the order of a few liters or tens of liters depending on the size of the installation, is surmounted by a roof-type cover allowing free passage of airflow but preventing rain falls.
• the exchanges are favored by a countercurrent between the air and the concentrated liquid percolating on the lining.
• the injection of the flow via the degradation tank of the material is preferably carried out gravitationally or, failing this, the pumping technology makes it possible to preserve the microorganisms injected into a favorable metabolism.
• a thermoregulation may be necessary in the case where the bioreactor 9 is not protected from freezing.
• the bioreactor 9 is designed to obtain a very limited consumption of inoculum to be implanted, because of the autonomy of the system which operates in permanent recirculation, this recirculation ensuring optimal contact for the mycelial population with the constituents promoting its development.
• the temperature is typically of the order of 10 to 30 ° C.
• a biological punctual analytical follow-up makes it possible to check the growth of the different species of mycelium constitutive of the selected cocktail.
• An analytical chemical monitoring, existing on the treatment stations makes it possible to be located on the performances of the system.
• the degradation time is predefined according to the initial characteristics but may vary according to the variations of flow treated upstream. It is a system which adapts perfectly to this kind of fluctuation: the analytical follow-ups make it possible to ensure the good performance of degradation.
• the method of treating by mycelial vision can be implemented by recirculation on the activated sludge, or on the water treatment die.
• the process is similar to that described both conceptually and dimensionally. Nevertheless, the variation ranges of flows, residence times, volume of the contact basin are different and generate optimizations imposing selection criteria for different works.
• the mycelial selection is the same and may even benefit from synergies between bacterial and mycelial flora.
• this oxidant is typically injected into the pretreatment tank 16 or in line according to the embodiments and residence times retained on the links 7 or 7a.
• FIG. 2 Another embodiment of the invention is described, involving a membrane filtration process of sludge treated with micromycetes.
• the installation 1 does not comprise a contact basin or mycelial digestion tank 8: the digestion of the sludge by micromycetes takes place directly in a pre-treatment basin 18 in which are immersed filtration 19.
• This basin 18 is similar to the basin 3 described above but also contains the filtration means 19.
• this pool 18 designated mixed treatment pool, combining treatment with micromycetes and membrane filtration, the sludge is optionally activated; basin 18 is aerobic.
• the treated water from the filtration means 19 is discharged through a pipe 20 to an outlet 21; the submergence water pressure of the module, supported by a suction pump downstream, allows the passage of treated water through the membranes. Water is directly rejected or even potentially usable for recycling. Indeed, the membrane walls make it possible to overcome a clarification step and the quality of the water is optimized. It is also possible to provide a backwashing system 21a.
• the sludge from the tank 18 is evacuated via a pipe 22 to a sludge die 23, for example dehydration.
• the installation may comprise separation means 24, extracted sludge.
• the sludge may be discharged through an outlet 25 or recirculated by circulation means 26 from the inlet filtrate 27 of the mixed treatment vessel 18.
• the installation comprises a bio-reactor 28 similar to the bioreaacteu 9 described above.
• micromycetes produced in the bioreactor 28 are conveyed to the mixed treatment tank 18 via a line 29.
• a portion of the filtrate from line 26 may be conveyed via line 30 to the inlet of the bioreactor 28.
• the membrane filtration means 19 is typically in the form of one or more modules 31 immersed in the mixed treatment tank 18.
• the process combines a biological treatment of wastewater with activated sludge with a high concentration of MES to a separation of the biomass from the water treated by the membranes.
• the membrane modules 31 may comprise an aeration at their base intended to ensure, on the one hand, the supply of oxygen necessary for the proper development of the biomass (air necessary for aeration of the sludge: required time of contact with the oxygen for the oxygenation of the mixed bacterial and mycelial culture), and on the other hand the passage of the mixed liquor through the membrane tissue.
• This large bubble aeration system can sometimes be associated with an additional fine bubble system in order to satisfy the needs.
• a suitable backpressure system can be used to allow for spot clearing of the membranes.
• a backwashing system can also allow this declogging.
• the permeability of the membranes ensures the retention of suspended solids as well as the majority of bacteria and germs. It is possible to use, for example, hydrophilic hollow fiber membranes having a permeability of the order of 0.1 to 0.4 ⁇ m.
• the total energy requirement of the process is of the order of 2 to 3 kWh / m 3 of permeate.
• the specific yield is of the order of 0.4 to 0.5 m 3 per m 2 / day.
• the combination of a micromycete treatment method and a membrane process makes the treatment conditions optimal.
• the sludge concentration in MES, MVS, etc. is greater than that conventionally encountered in the sludge die activated alone. This concentration is favorable for the mycelial process. - thanks to the coupling of the process, there is no more "mycelial tank” since the mycelial digestion is done directly in the activated sludge.
• the method of reducing the volume of sludge is compact is optimized.
• the membrane process per se, is described for example in documents such as Membrane Bioreactors for Municipal Wastewater Treatment - Husain et al - WQI March / April 1999.
• the coupling treatment with micromycetes, membrane process optimizes and further improves the treatment.
• the membranes constituting a carrier of microorganisms during air cleaning the film formed is not completely detached from the membrane tissue, this is an advantage.
• the selected mycelial cocktail develops and degrades the organic matter independently of this "intimate contact" created by the membrane between the sludge and the constituent mycelial strains themselves of the sludge. Nevertheless, this contact film accelerates the degradation reaction.
• the mycelial cocktail can be selected according to the texture of the membrane. Indeed, among the species cited in the first patent, we will select a suitable cocktail and promote the development of species, always in a catabolic mode, which will not damage the membrane tissues. The working criteria remain the same on the membranes, the working flow is very different according to the installations on average 20 to 30 l / m 2 / h for membranes realized in plate form for example.
• Micromycete strains which can be used in the previously described methods micromycetes, coupled treatment micromycetes / membrane process or association of oxidative pretreatment upstream of the mycelial treatment). These are of course non-pathogenic strains
• the inventor isolated various strains of micromycete fungi in sludge from several sewage treatment plants using appropriate techniques.
• These media are sterilized by heating at 120 ° C for 15 minutes before use. They are solid at room temperature.
• the isolation and quantification of the mycelial populations present in the sludge of purification plants were carried out using a technique of digitization by culture on Petri dishes, method known as Formant Units. Colony (UFC) or Selection by exhaustion. The samples are taken at the recirculation circuit of activated sludge ponds.
• This technique involves inoculating aliquots of suspensions-dilutions, made from the sample to be assayed, in or on a sterile culture medium suitable for the microorganisms to be evaluated.
• the study population underwent ten to ten dilutions (from 10 "1 to 10 " 7 ). At each dilution, 0.1 mL of solution was removed and then spread on the surface of a solid agar medium in Petri dishes (spreading is provided by a sterile disposable loop). For each dilution, two separate solid media are inoculated: GSC (Chloramphenicol Sabouraud Agar) and PDA (Glucose Agar with Potato Extract). This latter medium is less selective and more favorable for bacterial growth. GSC medium is specific for mycelial growth.
• the spores of a selected thallus are resuspended and then decimal diluted (up to 10-6 ) .
• the removal of the spores is done with a Pasteur pipette previously broken (as a scraper).
• the mildew center is recovered (spores + mycelium) and then resuspended in sterilized water, and in eleven samples, eleven molds were isolated.
• Culture medium is poured into test tubes (9 ml of medium per tube). Each tube is closed with cotton to protect the internal atmosphere from any external microbial contamination without suppressing the flow of oxygen. The whole is sterilized by autoclaving for 15 minutes at 120 ° C. At this temperature, the culture medium is liquid. At the outlet of the autoclave, the tubes are inclined so that the agar is up to 2/3. In less than an hour, the medium solidifies.
• Six slants were made by mold: • a slant is set aside and kept cold,
• the other four are intended to be resuspended and transferred to cryogenic tubes, the form in which the strain is integrated into the library. Eleven strains were purified. Seeding is done with a broken Pasteur pipette. The spores, scraped from the petri dishes in the third isolation phase, are suspended in the little water present in the bottom of the tubes (condensation due to the cooling of the medium). Spreading is then easy and is made by streaking down. We then carry out a conservation step and put in souchotèque. Once the incubation week has passed, the spores and mycelium are recovered. Finally, a purity and cleanliness check is performed to ensure that there are no contaminants. Production trials are initiated before the final entry of the strain into the commercial range. If the tests are conclusive, the strain is permanently integrated into the library: about fifty cryogenic tubes are prepared and stored, they serve as a reserve for the launch of future industrial productions.
• the preparation of pure cultures requires not only the isolation of a given microorganism from a natural population, but also the maintenance of this microorganism in an isolated atmosphere.
• Microorganisms are grown in small volumes and containers (test tube, Erlenmeyer flask or Petri dish). These containers must be sterilized before inoculation (UV, ray, dry or wet heat) and then protected against external contamination.
• PDA medium is less selective than GSC medium and less adapted to mold growth, colonies of bacteria and yeast will proliferate more easily.
• micromycetes The activity of micromycetes was measured using two contact ponds 8 (or process tanks) equipped with appropriate equipment for aeration, regulation, agitation: a process tank 8 in which the defined mixture (or cocktail) is injected, a control process tank 8 in which no mycelial cocktail is injected. Both vats are subjected to the same conditions of pH, temperature, aeration. The flow to be processed is exactly the same; only differs the biomass since in the process tank are the selected mycelial species. Numerous species, species associations but also essential parameters such as residence time, physicochemical parameters, have been tested.
• the residence time has also been tested in order to evaluate the growth of exogenous and endogenous flora and to choose the optimum in terms of degradation of organic matter taking into account the economic factor (more or less significant residence time involving more or less expensive installations).
• the inventor has confirmed the important effect of aeration on the development of the fungal cocktail in a mode favoring its degradative capacities.
• samples are taken at time 0 in order to carry out the budgets on the volume and the quantity of the sludge: by way of example and in a non-exhaustive way, the concentrations MES, MN.S, MS, NM, MM, but also nitrogen and phosphorus, COD as well as treated fluxes are quantified over the days
• Biological analyzes were carried out for the titration of the bacterial flora. After injection of the cocktail into the process tank (no injection in the control tank), biological analyzes were carried out for the titration of the bacterial and fungal flora. The titration accurately informs about the actual mycelial population.
• the test is done for example according to the following protocol:
• the continuous mode is set up using a daily feed (spread over a time slot) over a period of a few minutes per hour in succession to the daily extraction carried out on a period of a few minutes per hour; - taking a sample upstream of the process tank in order to carry out the assessments on the volume and the quantity of the mud actually brought into the mycelial digestion tank: as an example and in a non-exhaustive way, MES and MN .S, then MS, MN, MM, but also nitrogen and phosphorus, COD ... (with biological analyzes for the titration of the bacterial flora); - start up of the bioreactor with in situ production of the selected species;
• Sludge treated with micromycetes in the contact basin typically has the following concentrations.
• micromycetes to be administered to the sludge can be selected in order to better control the treatment, in particular as a function of the parameters of the installation (middle conditions of the purification of wastewater and residual sludge which are there, composition of the sludge, flow of the installation ).
• the life cycle of micromycetes, multicellular organisms offers several significant differences compared to bacteria: slower growth and different from that of bacteria, enzymatic material of degradation of organic matter more complex and oriented towards a wider variety of substrates.
• micromycetes represent about one-third of the oxygen required by a bacterial population.
• micromycetes will use all forms of available oxygen supply to optimize the degradation of organic matter. The process is thus qualified as low energy.
• mycelial species may also be chosen for their beneficial effect on plants, with useful applications for sludge intended for spreading: for example, strains known for their phytoprotective properties will be used. More generally, the methods described above offer a high degree of modularity and flexibility depending on the micromyecites chosen.
• This method also allows, without limitation, an improvement of the drainability of the sludge, a pre-hygiene of the sludge, changes in the C / N, C / P ratios.
• the performance of the treatment varies according to the operating conditions (selection of the parameters making it possible to achieve the optimum performances) but also according to the type of effluent and therefore of the substrate to be degraded.
• a certain number of possible pre-treatments (applied to the stream partially or totally) make it possible to increase the performances significantly.
• the sludge stress before the mycelial treatment is possible via the use of enzyme, thermophilic catalysts, acidification, ozone, osmotic shocks, other oxidants and oxidation reagents.
• performance clearly may be reached under specific conditions on given effluents.

Landscapes

• Life Sciences & Earth Sciences (AREA)
• Microbiology (AREA)
• Engineering & Computer Science (AREA)
• Biodiversity & Conservation Biology (AREA)
• Hydrology & Water Resources (AREA)
• Environmental & Geological Engineering (AREA)
• Water Supply & Treatment (AREA)
• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Molecular Biology (AREA)
• Health & Medical Sciences (AREA)
• Treatment Of Sludge (AREA)
• Activated Sludge Processes (AREA)
• Micro-Organisms Or Cultivation Processes Thereof (AREA)
• Separation Using Semi-Permeable Membranes (AREA)

Applications Claiming Priority (5)

Publications (1)

Family

ID=27767080

Family Applications (1)

Country Status (7)

Families Citing this family (21)

Family Cites Families (17)

• 2002
  • 2002-04-26 FR FR0205277A patent/FR2836910B1/fr not_active Expired - Lifetime
  • 2002-05-14 AU AU2002310666A patent/AU2002310666A1/en not_active Abandoned
  • 2002-05-14 EP EP02735535A patent/EP1483215A1/fr not_active Withdrawn
  • 2002-05-14 US US10/507,578 patent/US7270751B2/en not_active Expired - Fee Related
  • 2002-05-14 JP JP2003574577A patent/JP2005526595A/ja active Pending
  • 2002-05-14 RU RU2004129754A patent/RU2303572C2/ru active
  • 2002-05-14 WO PCT/FR2002/001608 patent/WO2003076351A1/fr active Application Filing

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events