RO135260A0 - Device and process for washing sediments and separating granulometric fractions of micropaleontological samples - Google Patents

Abstract

The invention relates to a device and a process for washing sediments and separating the granulometric fractions of micropaleontological samples, in order to prepare them for qualitative and quantitative analyses used in paleoclimatic studies. According to the invention, the device consists of a sieve battery (5) fixed with a system of vertical metal rods (2) which are mounted on a lower support (8) and on an upper support (9), it has a source of water with a tap (1) to which an enclosure (3) is mounted and provided with a lid with perforations on the whole surface, to uniformly wash the sediment (4) with pressurized water jets, the water resulted from washing together with the clay fraction being discharged through a drain (7) into a decanter which is connected to the sewage system, at the bottom of the device there is mounted a mechanical vibration system consisting of an electric motor (6) which, by means of a eccentric gearing mechanism, produces vibrations which are transmitted to the sieve battery (5), and the lower support (8) is fixed to the work table (11) by means of screws (10) provided with elastic sleeves/rubber spacers which provide the vibration damping in relation with the work table. The claimed process consists in introducing the wet sediment (4) into the sieve at the top which has a mesh size of 1 mm, opening the tap (1) and letting the pressurized water inside the enclosure (3), provided with perforations, uniformly washing the sediment (4) with fine water jets, the sediments being disintegrated with increased efficiency so that the granulometric fractions remain in the sieves with increasingly fine granulations, the finest fraction, which contains the microfauna, being collected from the last sieve with a mesh of 0.063 mm.

Description

DEVICE AND PROCEDURE FOR SEDIMENT WASHING AND SEPARATION OF GRANULOMETRIC FRACTIONS OF MICROPALEONTOLOGICAL TESTS

The invention relates to a device and a process for washing sediments and separating the particle size fractions of micropaleontological samples, in order to prepare them for qualitative and quantitative analyzes used in paleoclimatic studies.

Biostratigraphic studies (macrofauna, microfauna and nanoflora, as well as absolute ages) are used to date the Holocene deposits. Microfauna studies focus on the analysis of ostracodes and foraminifera. Micropaleontological studies are extremely important for paleoclimatic reconstructions and implicitly for the current understanding of the global warming process. These studies use microscopic fossils, namely shells and ostracode and foraminiferal valves. In order to identify them at the species level, it is essential that the valves and shells be thoroughly cleaned.

Micropaleontological studies are performed on sediments from cores taken with a gravitational core. After extracting the cores, 100 g of sediment is collected in plastic boxes or plastic bags. Unconsolidated sediments taken with a gravity core are then subjected to the washing process.

The analysis of benthic ostracodes and foraminifera is useful for identifying paleoenvironmental changes, especially salinity and temperature during sediment deposition. The carrot material is analyzed in its entirety after washing, extracting not only all the ostracode valves and shells, but also other microfossils, such as foraminifera, fish remains and gastropods, for biostratigraphic interpretation. Macrofauna associations (especially molluscs, of which the bivalve group is illustrative for paleomedical changes) are also described for all samples taken. This group of organisms is also important for environmental restorations, such as changing salinity. In particular, the intervals containing freshwater faunal associations as well as those characterizing intervals shall be monitored.

marine depositions, but also the transition between these types, related to lithological / sedimentological changes. Their description is made after the washing process, the bivalves remaining cleaned in the sieve with the largest mesh (1 mm).

Sediment washing devices are known which use fine water jets which perform the action of washing the sediment. They have rotating arms mounted over the sieve battery, washing the sample with fine jets of water.

The disadvantages of these devices are that they do not ensure a uniform and complete washing of sediments containing microfossils. Also, the time required to wash a sample is relatively long. Thus, the efficiency of the whole washing operation is low.

Ultrasonic devices are known to clean fossils after washing clayey sediments.

The disadvantages of these devices are that the time spent on this cleaning process is long and that it is done after the washing process.

Vibrating devices with a sieve system for separating particle size fractions using sieve batteries of different sizes are known.

They have the disadvantage that they are only used in the processing of dry and unconsolidated sediments, and cannot be used for washing wet sediments (sludge and / or clays).

The technical problem solved by the claimed inventions within the group of inventions is the particle size sorting, the washing of the sediments and the complete cleaning of the microfossils without them being damaged, in a short time.

The device according to the claimed invention eliminates the disadvantages shown above by the fact that in its composition there is a sieve battery fixed with a system of vertical metal rods which are mounted on the two supports,

bottom and top and a tap water source to which a chamber fitted with a lid with perforations on the entire surface is mounted, thus washing the sediment with water jets under pressure under uniform pressure, and the water resulting from washing together with the clay fraction is discharged through a drain into a decanter which is connected to the sewer system.

The device according to the claimed invention further comprises at its lower part a mechanical vibration system consisting of an electric motor which, by means of an eccentric mechanism, produces mechanical energy in the form of vibrations, applied to the sieve battery, the lower support is fixed to the table. work by means of screws provided with rubber sleeves / spacers, this elastic fixing of the sieve battery ensuring the damping of the vibrations in relation to the working mass.

The process according to the claimed invention removes the disadvantages shown above by the introduction of wet sediment (sludge and / or clays, taken from the ground) into the sieve at the top which has a mesh size of 1 mm, and by operating the tap water enters with pressure an enclosure provided with a perforated lid, applying fine jets of water on the sediment, the process of uniform washing of the sample starts, under the action of water, the sediments disintegrate with increased efficiency, the particle size fractions remain in the finer sieves, the fraction the thinnest, containing the microfauna, is taken from a 0.063 mm mesh sieve at the bottom of the sieve battery, which is then subjected to ultrasonic washing.

The process according to the claimed invention also shows a vertical vibratory movement of the sieve battery, produced by the electric motor which has an eccentric mechanism, which leads to an increase in the rate of disintegration and washing of sediments.

The advantages of the device and process for washing micropaleontological samples according to the inventions are the following:

- Uniform and complete washing of sediments containing microfossils by removing small particles from the inside of the shells;

- A separation of the granulometric fractions is performed simultaneously with the washing process of the microfossils;

- Complete cleaning of microfossils with the help of ultrasound;

- The total time from the moment of collecting the samples to their washing and implicitly to the cleaning of the microfossils is significantly reduced, thus increasing the efficiency of using the time given to the analyzes;

The following is an embodiment of the device and the application of the method according to the claimed inventions, respectively, in connection with Figure 1 and Figure 2, which represent the overall sketch of the device and the ultrasonic bath, respectively.

Figure 1 shows the overall outline of the device for washing sediments and separating the particle size fractions of the micropaleontological samples, comprising; water source (1) with tap, vertical metal rods (2), enclosure (3) with cover with perforations on the whole surface, sediment (4) subjected to the process of washing and sorting, sieve battery (5), engine (6) for generating mechanical vibration, drain (7), lower support (8), upper support (9), screws (10) and work table (11).

The device according to the invention consists of a sieve battery (5) mounted on a metal support (2) consisting of two rods, which are mounted on a lower support (8) by means of screws (10) provided with elastic rubber spacers. in connection with the metal support (2) is an electric motor (6) which converts electrical energy into mechanical vibrational energy.

The sieve battery (5) consists of an increasingly thin sieve with a mesh diameter of 1,000 mm, 0.500 mm, 0.250 mm, 0.125 mm and 0.063 mm (5). The sieves are made of stainless steel and their size is 200 mm in diameter and 50 mm high. Each sieve is equipped with a gasket

rubber that seals the entire sieve battery so that water mixed with fine sediments is not lost laterally during the washing process. Above this sieve battery is a water source provided with a tap (1) to which a chamber (3) is fitted with a cover with perforations on the entire surface. The water is supplied by the tap (1), and is evenly dispersed throughout the sieve battery (5), by the enclosure (3) provided with a perforated cover. The perforated cover associated with the enclosure (3) is provided with holes with a diameter of 1 mm arranged in a reticular network with a side of 5 mm.

The sieve battery (5) is fixed with a system of vertical metal rods (2) which are mounted on the two supports, lower (8) and upper (9). At the bottom of the device is a mechanical vibration system consisting of an electric motor (6) which, by means of an eccentric mechanism, produces mechanical energy in the form of vibrations, applied to the sieve battery (5). The lower support (8) has a conical recess to facilitate the drainage of water resulting from the washing process. This lower support (8) is fixed to the work table (11) by means of screws (10) provided with spacer sleeves. This type of elastic fastening of the sieve battery (5) ensures the damping of the vibrations in relation to the working mass (11). The vibration of the sieve battery (5) increases the efficiency of the process of washing and sorting the sediment containing the microfauna (4).

The water resulting from the washing and sorting process, which contains only the clay fraction, is discharged through the drain (7), the microfauna being retained by the sieve battery (5). Finally, the water containing the clay fraction is removed by means of a decanter in the sewer system.

Figure 2 shows the ultrasonic bath (12) containing distilled water (13) in which the fine fraction containing the microfauna and sediment with a residual clay mineral content (14) is thoroughly cleaned due to the action of the ultrasonic energy generated by the device ( 15).

The process according to the invention consists in introducing the wet sediment (4) (sludge and / or clays, taken from the ground) into the sieve at the top which

has an eye size of 1 mm (5). By operating the tap (1) the water enters the enclosure under pressure (3) provided with a perforated lid, applying on the sediment (4) fine jets of water triggering the process of uniform washing of the sample. Thus, under the action of water, the sediments disintegrate and the particle size fractions remain in the finer sieves (5). The thinnest fraction, containing the microfauna, is taken from a 0,063 mm mesh sieve at the bottom of the sieve battery (5) and subsequently subjected to ultrasonic washing. This whole washing process is enhanced by a vertical vibrating motion produced by the electric motor (6) by means of an eccentric mechanism. This vibration process increases the rate of sediment disintegration and washing. The water resulting from the washing and sorting process, which contains only the clay fraction, reaches the surface of the lower support (8) which is slightly deepened in the form of a funnel, from where it is discharged through the drain (7). Finally, this water, which contains the clay fraction, is sent through a decanter into the sewer system. Thus, the fine fraction, which also includes the microfauna, reaches the fine sieve of 0.063 mm, from where it is subsequently introduced into the ultrasonic bath shown in Figure 2. Here, the fine fractions containing the microfauna, after being thoroughly cleaned by the ultrasonic system , are collected, dried and studied under a microscope.

Claims (4)

1. The device for washing sediment and separating the particle size fraction of the micropaleontological samples, into which the sediment taken from the field and to be washed with water is introduced, is subsequently subjected to a fine ultrasonic cleaning process characterized in that its composition has a sieve battery (5) fixed with a system of vertical metal rods (2) which are mounted on the two supports, lower (8) and upper (9) and a source of tap water (1) to which it is mounted an enclosure (3) with a lid with perforations on the entire surface, thus washing the sediment (4) with jets of water under uniform pressure, and the water resulting from the washing together with the clay fraction is discharged through a drain (7) in a decanter which is connected to the sewer system. Device according to Claim 1, characterized in that a mechanical vibration system is installed at the bottom of the device consisting of an electric motor (6) which, by means of an eccentric mechanism, produces mechanical energy in the form of vibration, applied of the sieve battery (5), the lower support (8) is fixed to the work table (11) by means of screws (10) provided with rubber sleeves / spacers, this elastic fixing of the sieve battery (5) ensuring the vibration damping in in relation to the working table (11). 3. Process for washing sediments and separating the particle size fraction of micropaleontological samples characterized by the introduction of wet sediment (4) (sludge and / or clays, taken from the ground) into the upper 1 mm mesh sieve (5), by actuating the tap (1) the water penetrates under pressure into an enclosure (3) provided with a perforated lid (3), applying on the sediment (4) fine jets of water the process of uniform washing of the sample is initiated, under the action of water, the sediments disintegrate with increased efficiency, the particle size fractions remain in the finer sieves (5), the finer fraction, which contains the microfauna, is taken from the sieve with a mesh size of 0.063 mm, located at the bottom of the battery. site (5). 4. Process for washing sediments and separating the particle size fractions of the micropaleontological samples, characterized in that they also show a vertical vibrational movement of the sieve battery (5), produced by the electric motor (6) which has an eccentric mechanism, which leads to the increase sediment disintegration and washing rate.