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
  • C02F3/28—Anaerobic digestion processes
  • C02F3/2806—Anaerobic processes using solid supports for microorganisms
• • 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
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S210/00—Liquid purification or separation
  • Y10S210/902—Materials removed
  • Y10S210/903—Nitrogenous
• • 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
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S435/00—Chemistry: molecular biology and microbiology
  • Y10S435/813—Continuous fermentation
• • 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
  • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
  • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y10S435/00—Chemistry: molecular biology and microbiology
  • Y10S435/8215—Microorganisms
  • Y10S435/822—Microorganisms using bacteria or actinomycetales
  • Y10S435/874—Pseudomonas

Definitions

• the present invention relates to a biological denitrification process having high performance.
• the biological processes apply mainly to urban effluents with low nitrate content (of the order of 100 mg / 1) and those which make it possible to operate at higher concentrations (3.5 g / I d nitric nitrogen and more) have denitrification rates of the order of 1 to 1.5 mg of nitrogen per liter per hour.
• the Applicant has developed a process applicable in particular to industrial wastewater, making it possible to reduce the nitric nitrogen present in effluents to concentrations up to 10 g / t, and this at a high speed of transformation, while minimizing the carbon substrate concentrations required for denitrification.
• the performances obtained in this process with the use of a fluid bed reactor are superior to all those known for the same type of reactor, as described by J. S. JERIS et al. W.P.C.F. Flight. 46 No 9 - Sept. 1974 (2043-2057), B. ERICSSON Journal W.P.C.F. Flight. 47 No. 4 - April 1975 (727-740), C. W. FRANCIS et al. Water Res. Flight.
• This process consists in manufacturing an active denitrification support formed on the one hand from selected denitrifying bacteria and on the other hand from very fine calcium carbonate.
• the process is characterized by the prior selection of a denitrifying flora adapted to a given exogenous carbon substrate containing calcium nitrate.
• This support formed in situ can consist of a central core (carbon or CaC0 3 ) on which the selected denitrifying bacteria and the calcium carbonate formed by the denitrification reaction are fixed.
• the possible addition of a mixture of trace elements makes it possible to increase the denitrification rates.
• the active denitrification support obtained by the process of the applicant can be used in any kind of denitrification reactor (homogeneous react, column reactor with fixed bed or with fluid bed).
• strains of bacteria with denitrifying activity are selected according to the organic carbon substrate used in denitrification (alcohols, urban effluent, factory effluent), according to the type of nitrates and according to the concentration of the latter.
• strains are subjected to enrichment by successive subcultures in a liquid medium while achieving the best possible anaerobiosis.
• the media used are of the type described below with possible addition of yeast extract at a rate of 1 g / l.
• the enriched denitrifying strains thus obtained are then isolated, the isolation being carried out on a solid medium in an anaerobic test jar.
• the growth of the colonies requires 8 days at 30 ° C.
• the selected strains are placed in preculture in an anaerobic reactor with a nitrate and carbon substrate in order to allow an induction of denitrifying activities as well as a production of biomasses having this activity.
• the biomass is then harvested by centrifugation or decantation before being resown in the effluents to be denitrified.
• the effluent before sowing is optionally degassed by suitable methods (nitrogen bubbling, heating, addition of sulfites).
• the start of the process consists first of a complete recycling of the effluent loaded with microorganisms. This recycling is necessary on the one hand to allow the induction of the denitrifying activity, on the other hand to allow maximum fixation of the microorganisms on the support.
• CaC0 3 and denitrifying bacteria are formed during the same reaction.
• This reaction is a Ca (NO 3 ) 2 denitrification reaction; it can therefore be carried out at the start of the denitrification operation, with the apparatus provided for the final treatment.
• the active denitrification support thus formed has proven to be very effective in the various reactors used and in particular in fluidized bed reactors.
• the denitrification temperature can vary from 5 to 40 ° C, but is preferably around 30 ° C.
• the denitrification is carried out so as to have a basic output pH facilitating carbonation.
• the calcium carbonate gradually surrounding the coal particle is a by-product of denitrification. It also acts as a pH buffer.
• a homogeneous reactor is seeded with the denitrifying bacteria.
• a denitrification medium consisting of an organic carbon substrate (here glucose) and necessarily calcium nitrate. It is possible to add to the denitrification medium powdered charcoal which will serve as the primary support for the fixation, on the one hand of the calcium carbonate grains formed during the denitrification reaction and, on the other hand, denitrifying bacteria which are developed in the denitrification medium.
• the sludge formed is very active in terms of denitrification. They can be used with any type of reactor and with any source of substrate.
• the CaC0 3 support with its denitrifying biomass was produced beforehand in a homogeneous reactor as in Example 1: denitrifying strain of the genus Pseudomonas seeded in a medium containing Ca (N0 3 ) 2 + fine carbon + methanol. The culture is maintained anaerobically.
• a solution of trace elements (1 ml / l) is added to the denitrification medium.

Landscapes

• Life Sciences & Earth Sciences (AREA)
• Microbiology (AREA)
• Biodiversity & Conservation Biology (AREA)
• Hydrology & Water Resources (AREA)
• Engineering & Computer Science (AREA)
• Environmental & Geological Engineering (AREA)
• Water Supply & Treatment (AREA)
• Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Purification Treatments By Anaerobic Or Anaerobic And Aerobic Bacteria Or Animals (AREA)
• Biological Treatment Of Waste Water (AREA)
• Micro-Organisms Or Cultivation Processes Thereof (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=9193165

Family Applications (1)

Country Status (13)

Families Citing this family (13)

Family Cites Families (18)

• 1977
  • 1977-07-08 FR FR7721119A patent/FR2396726A1/fr active Granted
• 1978
  • 1978-06-19 IT IT6842978A patent/IT1111478B/it active
  • 1978-07-03 EP EP19780400049 patent/EP0000461B1/fr not_active Expired
  • 1978-07-03 DE DE7878400049T patent/DE2861782D1/de not_active Expired
  • 1978-07-06 AU AU37808/78A patent/AU520638B2/en not_active Expired
  • 1978-07-06 US US05/922,343 patent/US4209390A/en not_active Expired - Lifetime
  • 1978-07-07 SE SE7807648A patent/SE436349B/sv not_active IP Right Cessation
  • 1978-07-07 DK DK306278A patent/DK306278A/da not_active Application Discontinuation
  • 1978-07-07 BR BR7804409A patent/BR7804409A/pt unknown
  • 1978-07-07 IE IE1365/78A patent/IE47023B1/en unknown
  • 1978-07-07 ZA ZA00783913A patent/ZA783913B/xx unknown
  • 1978-07-07 NO NO782380A patent/NO151700C/no unknown
  • 1978-07-07 CA CA000306976A patent/CA1118377A/fr not_active Expired
• 1979
  • 1979-12-21 US US06/106,037 patent/US4318988A/en not_active Expired - Lifetime

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