FR2464232A1 - PROCESS FOR TREATING SLUDGE AND INDUSTRIAL WASTE - Google Patents

Abstract

THE INVENTION CONCERNS A PROCESS FOR TREATING SLUDGE OR SOIL AND INDUSTRIAL WASTE BY PRESSURE MOLDING. EACH OF THE STARTING MATERIALS OF DIFFERENT PARTICULAR CONTROLLED DIMENSIONS IS MIXED IN ORDER TO OBTAIN AN OPTIMAL COMPACT STRUCTURE, WHILE ELIMINATION OF THE AGGLOMERATED STRUCTURES IN THE MIXTURE, AND CALCIUM SALT IS ADDED TO THE BINDING BINDER CEMENT. THE MIXING OF THE SAID MATERIALS IS CARRIED OUT BY MEANS OF A MIXER EQUIPPED WITH ROLLERS FOR A SUFFICIENT PERIOD OF TIME, THEN THE PRESSURE MOLDING IS CARRIED OUT IN A MOLD EQUIPPED WITH PERFORATIONS FOR VACUUM FLOWING, SO THAT THE ARTICLES ARE OBTAINED. MOLDS SUCH AS BUILDING BLOCKS WITH EXCELLENT PHYSICAL PROPERTIES.

Description

The invention relates to a method of treating sludge and residues

  in particular using the mixture of materials of different particle size

  to obtain a structure with optimum compactness

  male. The agglomerated structures of the materials used

  are removed, then calcium salt is added before

  produce cement binders and sodium silicate. In addition, the materials are mixed with a roller mixer for a sufficient time while simultaneously controlling the water content of said mixture, and then pressurized mold in the molds provided which are perforated to allow adequate evacuation of water under vacuum, and

to obtain molded products.

  So far, it is known that solid industrial residues

  triels are often treated so as to be buried or

  transformed by combustion into ash that can be removed. Toute-

  There are many varieties of industrial waste

  non-combustible which pose a serious problem of destruction.

  In addition, the control of the surrounding pollution increases

  enough this problem and the regeneration process re-

  non-combustible solid residues

  construction and civil engineering, further increases the

lift of this problem.

  Consequently, the main object of the present invention

  is a process for the treatment of solid residues

  non-combustible and thus to obtain valuable materials

  riseable while avoiding secondary pollution.

  Another subject of the invention is a process for the treatment of residues, in particular those which come from

  civil engineering and construction industries.

  Another subject of the invention relates to a method for treating ash from urban waste in order to obtain molded products free of any pollution.

  d e to heavy metals. In addition, the process according to the invention

  The treatment also concerns the treatment of the re-use of industrial water. In addition, the invention also relates to a process for mixing industrial waste of different types in order to obtain valuable materials. The

  other objects and advantages of the invention will be

  using the following description.

  According to the method which is the subject of the present invention for

  the treatment of industrial waste and residues,

  together different materials of different particle size

  controlled in order to obtain an optimal compact structure, while at the same time eliminating the

  agglomerates, then add the calcium salt before adding

  cement and sodium silicate binders. In addition, the mixing is carried out by means of a roller mixer in order to obtain a sufficient mixture while controlling the moisture content in the mixture and then mold under pressure.

  mixing into a suitable mold with perforations

  permitting adequate drainage under vacuum to

to obtain molded products.

  Therefore, the following points are essential to carry out the process according to the invention: 1- Maximum size of the particles to be treated: the maximum particle size should not exceed a diameter of 5 (five) cm; - Control of particle size distribution in the starting mixture:

  The materials to be treated must be mixed

  to obtain an optimum mixing ratio of different particle sizes, such as 9 parts of coarse ash, 2 parts of fine ash and 1 part of industrial sludge in order to obtain a maximum compactness in structure. In ordinary circumstances, one can

  to create a molded structure with excellent

  properties using for example sludge, adding two parts of sandy sludge to one part of sludge

  argillaceous material, or, for example, a part of sand sludge

  to half a portion of clay sludge and thereby improving the permeability and density of the material. Thus, it is clear that particle size control in the mixture is essential for the process.

according to said invention.

  2- Total elimination of agalomerate starting materials: In general, the arqile comprises various particles

  less than 74 p that are physically agglomerated

  This is done by the water from the environment, in addition to a set of ions, which forms the equilibrium structure of the sludge. As a result, cement and similar binders can not penetrate the spaces between the agglomerated sludge structures. Of another

  On the other hand, the water easily enters the spaces between

  structures and destroys the agglomeration of the structures by increasing the volume by approximately 9%, which corresponds to approximately 150 kg / cm2 of pressure, when cooling beyond the freezing point and

  repeated freezings will completely destroy the

molded duit.

  As a result, the agglomerated structures will be

  severely destroyed in order to obtain molded products

  having excellent properties under any weather conditions

  ture. Therefore, conventional concrete mixers can not be used for this process, but a special mixer with rollers (mixer

with rollers).

  The differences in physical properties of the respective products obtained using a conventional mixer or a special roller mixer are shown in the following table: (see next page) Sample: Kanto slurry Effort at compactness: 90kg / cm2

  Resistance: after 28 days in the air.

  The distribution of dimensions for the destruction of

  agglomerates is essential for the present invention.

  tion. -4- resistance to resistance to compressive stability bending during freezing Convection mixer 53kg / cm2 6.4 kg / cm destroyed Mixer with 2 rolls 106 kg / cm2 11.4 kg / cm stable 3L ' addition of calcium salts before the addition of binders: The solidification of the cement as a binder can be

  made by calcium ions from calcium salts

  cium. However, materials derived from

  usually contain impurities of heavy metal ions and organic materials as in sludge, so that calcium ions are absorbed

  before they can act with bonding cement.

  Thus, the presence of heavy metal ions and

  Organic materials in the starting mixture will alter the solidification process of binders such as cement. To avoid this type of problem, we can add 3 to 5% in

  weight of calcium salts to the starting mixture before adding

  cement or other binders.-We can then observe

  clearly the effect of the pre-addition of calcium salts.

  After that, preferably 20% of cement and 3 to 5% of sodium silicate (based on the amount of mixing) can be added as binders. Sodium silicate is an important additive to produce non-polluted molded products

  which are not subject to erosion.

  4- Control of the water content of the mixture:

  The water content of the mixture greatly influences the effectiveness

  cited of this process and the properties of the product. By con-

  optimum moisture content must be maintained

  in order to achieve compactness and resistance

  at the optimum temperature, before the molding operation.

246423Z

  -5-- For example, the optimum water content in the Kanto loam melanae with Narita sand is

18 to 24%.

  - Preferable mixing time: In the case of a mix of Kanto loam and Narita sand, the optimal mixing time may be 15 minutes. A shorter melting time will give insufficient mixing properties while a longer mixing time will cause reagglomeration of the soil particles and at the same time will prevent achieving the desired compactness. So the mixing time has to be

  kept in optimum range.

6- Moulaae under vacuum pressure:

  To avoid the effect of over-compactness, the operation of

  lage must be vacuum driven. A special mold includes

  a device for the evacuation of both air and

  the water contained in the mixture is used for this purpose.

  To obtain the desired physical properties, the compactness force Q must be maintained above the value of 20 kg / cm 2 and a molding time approximately

  between 30 and 50 seconds is necessary.

  Description of the invention with reference to the drawings

attached:

  FIG. 1 represents an elevational view, with

  section of the preferred embodiment of the product thus molded according to the invention, FIG. 2 represents a flow diagram of the process applied to the sludge, and the molded products according to the invention.

said invention.

  Figure 3 shows a flow diagram of the

  applied to ash from industrial waste.

  in accordance with the present invention, and Figure 4 shows a flow chart

  the process applied to industrial sewage sludge, in accordance

in accordance with the invention.

  Referring to Figure 1, the materials to be mixed are finely divided, the calcium salt is added, and then the binders, comprising cement and sodium silicate are added. The mixture is introduced into the mold (A), comprising a filter cloth (B) and a filtering network (C), equipped with drainage drainage in the direction of the arrows, to evacuate the water and air in excess accumulated in the mold. It will be noted that in this way, the split-type mold, which was previously difficult to use, can be easily filled with crushed stones, and in particular

  according to the method of the present invention, by

  holding a sheet of film (E) in the middle of the material (F)

  loaded into the mold. This has a very important

aunt in this technique.

  FIG. 2 represents an operating diagram of the method applied to the molding of sludge in accordance with FIG.

  present invention. Reference 1 indicates glue sludge

  Kanto seams, in coarse particles, the reference 2

  indicates sand consisting of fine particles. The references

  1, 3, 4 and 5 respectively denote the grinder, the roller mixer, the discharge mold according to

  to the present invention, and the product obtained. The references

  6 and 7 denote the cement silo and the lime silo respectively, and the reference 8 designates the reservoir

of water.

  Figure 3 shows a flow diagram

  applied to industrial waste, where

  In this case, fine particles 2 "and sludge 9 are mixed in the ratio 7: 2: 1 in a mixer equipped with rollers 3, slaked lime is added in 6 and 7

  white cement with sodium silicate, and then

  kills the compression and vacuum molding in 4 while

controlling the water content.

  FIG. 4 represents an example of a flow diagram of the process applied to sludges from

  industrial wastewater in accordance with this -

  Invention. In this example, the sewage is separated

  solid elements by means of a technique

  only by sedimentation and coagulation while controlling

  The sludge thus obtained from steps II and 12 are then mixed with ashes.

  additional - coarse and fine fractions

  from industrial waste, then to slaked lime, cement and sodium silicate. The

  mixture is molded under pressure in the mold 4 under

  the water content, in order to obtain the product 5.

  The following examples explain the present invention in more detail, all percentages and proportions

  being expressed at the weight of dry materials.

  Example 1: A portion of Kanto clay soil was mixed with a portion of coastal sand, then 5% slaked lime and 15% cement as well as water were added to this mixture. After a mixing time of 15 minutes, the mixture is loaded and molded under pressure in a molding block under a pressure of 120 tons for 30 minutes.

  seconds under vacuum (compression force: 20 kg / cm 2).

  The product thus molded has a compressive strength.

  150 ka / cm2 and a flexural strength of

  14 kg / cm 2, a permeability coefficient of 4.10 8 cm / sec.

  and a water absorption coefficient of 5%. Thus, the

  duit is suitable for use as road material or earth dam for retaining dikes. then

  subsequent tests, the product was not destroyed during

  that it has been subjected to freezing cycles or

fusion tests.

  Example 2: Part of Narita sand was mixed with a portion of high water sludge sampled from the bed of Tokyo Bay. 2% slaked lime and 10% cement were added, followed by mixing sufficient to remove agglomerates. The mixture thus obtained was loaded into a mold according to the present invention and then compression molded at a pressure of 120 tons (compact force: 20 kq / cm) for 90 seconds and empty. The product thus obtained has a compressive strength greater than 100 kq / c 2 which is not destroyed and is not destroyed by freezing and fusicidal tests. On the other hand, the sample which does not contain slaked lime has a compressive strength of less than 30 ka / cr2 and decomposes after approximately one hour by water obstruction

when immersed in water.

  Example 3: One part of Kacoshima Sirasu earth was melanae with a part of Narita sand, then 2% of slaked lime and 15% of cement were added with water. We have

  introduced this melanae into a mold and molded under

  120 tons under vacuum. The molded product thus presented

  a resistance to bending of 13.84 ka / cm 2, a resistance

  compressive strength of 98.01 kg / cm 2 and a permeability coefficient of 2.46 x 10-8 cm / sec. The product is also stable during seven freezing cycles and melting tests. Example 4: ash from waste is mixed

  urban areas containing 29% water (Chitose, Directorate for Pre-

  Tokyo Prefecture) with industrial water sludge

  trials according to the proportion of 9 parts of coarse ash

  two parts of fine ash and a part of mud.

  1 ml of this mixture was used and 131 g FeCl 3, 333 g slaked lime, 1% organic deodorant,% cement and 2% slaked lime were added. After mixing components for a sufficient time, we have

  then introduced the mixture into a mold according to the invention.

  and compressed under vacuum at 120 tons

  seconds. The product thus obtained has a resistance

  compression ratio of 180 kq / cm 2 and a density of 2.3.

  Repeated tests of conqelation and fusion between -20 C and 30 C show that the physical properties are

stable.

  EXAMPLE 5 Industrial residues from a wool lava tank were treated in a furnace, this furnace having a capacity of 2 m 3 per day of ash, 0.2 m 3

  wool ash and 0.7 m3 of sedimented material per day.

  The ashes above and the sediments were mixed in a proportion of 58/32/10 and then pressure molded of tonnes. The product obtained has a flexural strength of 39.39 kg / cm 2 and a compressive strength

142.1 ka / cm2 after 4 weeks.

  Although the present invention has been illustrated by

  the detailed description of several embodiments

  preferred, it is obvious to those skilled in the art that

  variants of form and detail may be

  without thereby departing from the scope of the said inven-

  defined by the following claims and not by

  the embodiments mentioned above.

-10-

REVLENDICATIONS

  1- Process of treatment of sludge and industrial waste, characterized in that it comprises mixing materials of different controlled particle sizes in order to obtain an optimum compact structure, and in order to eliminate the aqaloméré structures in the mixture, adding calcium salt before adding

  of cement and sodium silicate binders, then mix

  of said materials by means of a mixer equipped with rollers for a sufficient time while controlling

  simultaneously the water content of said mixture, then the mold

  pressurizing this mixture into a mold with perforations for vacuum drainage to obtain molded articles having excellent properties

physical.

  2- Process according to claim 1, characterized in

  molded articles form building blocks

  consisting of land, ashes and / or industrial waste.

  3. Process according to claim 1, characterized in that said materials are industrial sludge in order to obtain building blocks without pollution.

heavy metal.

  4. Process according to claim 1, characterized in that slit-type building blocks are produced by introducing a sheet of film in the median position.

  in the material introduced into the mold.