Research & Development

The main reason for the MEBIOR factory group acquisition was the given opportunities provided for further Research and Development of Industrial Minerals, which had already been a Research & Development field for the founder and sole shareholder of OLYMPUS SA, as well as R&D of other minerals and sub-products that have not been exploited yet in our country, as the reason for the establishment of the Company was mainly R&D in the field of innovative minerals.

Indicatively, are mentioned the clay diatomites of Elassona, the Pozzolans of Pella, the zeolite of Evros and the dry and granulated pumice stone along with production of quartz and quartzite from other quarries and recyclables.

Particularly:

Clayey Diatomite

The private area of 65 acres owned by the founder, 33 of which hold an Exploitation License and have been sold to OLYMPUS SA , and the rest have all data required to be licensed.

The clayey diatomites of the Sarantaporos basin of Elassona, part of which is the above, have been extensively studied geologically, but industrial research, i.e. pilot-plant research, to produce competing products targeted to specific uses was non- existent.

Image under electronic microscope of the Greek diatomite of OLYMPUS SA.
Front of the Elassona diatomite research excavation

SEM photo after calcination

In the field of laboratory scale of research only, the extensive work of the University of Athens, Department of Geology, by professor M. Stamatakis should be mentioned on the production of Light Weight Aggregates with participation in various European Research Programs.
The diatomite of this area consists of disc-shaped and cylindrical diatom shells consisting of amorphous SiO2 (Opal-A) clayeys of the smectite and Illite group with a diatomite-to-clay ratio approximately 50/50 (which increases after air separation to a ratio of 75/25).
Explorative excavations at the licensed site in relation to the surface outcrops on the specific area of 65 acres and drilling performed by other operators in the wider area and resulting in a thickness of 40 meters of clay diatomites, give an estimate probable reserves size of 3.000.000 tonnes on this property.
Industrial research was based on the main characteristic of calcined at 800C diatomite which is low apparent density associated with porosity and strengthness. Thus, the research turned to the possibility of producing lightweight thermo-insulative building elements on the one hand and absorbent materials on the other.
Light Weight Aggregates LWA research has already carried out by the University of Athens on a laboratory scale as mentioned above.
It should be noted here that the Danish Clay Diatomite, similar to our main features (Fur island), exploits extensively in both directions, namely the production of heat-insulating components and absorbents, with a main export orientation.

Industrial research on thermal insulation components was a comparative evaluation of comparable market products such as Ytong and Porotherm bricks. It was carried out at the Belgian National Institute of Silicon and Materials Research at Mons
(Institut National Interuniversitaire des Silicates, Sols et Materiaux INISMA) and was funded by G. Georgiadis (quoted as such in English).

After extensive measurements, the optimum firing temperature (900 C) was determined, beyond which the image of the diatoms changes (blurriness) although their structure is not affected as dramatically shown in the microscopic photographs (X1000), thus almost doubling their strengths, as well as increasing the density of the material as it has an adverse effect on the thermo-sound insulation properties.

The comparative evaluation in terms of thermo-sound insulation of the products, classifies them between the two products of Ytong and Porotherm (baked at 950 C – approximately equal energy consumption) while compressive strengths exceed both.

Photo in a X1000 optical microscope at various calcination temperatures.

Industrial research for the production of absorbents was carried out on a pilot-plant scale at the Centre Technologique International de la Terre et de la Pierre In Tournai, Belgium on a representative 20 tonnes sample of the licensed OLYMPUS SA quarry and was funded by G. Georgiadis.

Pilot-Plant scale research (1)

Pilot-Plant scale research (2)

Pilot-Plant scale research (3)

The research resulted in all the elements needed to create an industrial unit of calcined absorbent diatomite granules , i.e. fracture conditions and the percentage of fines that are lost and removed by screening before the material enters in the rotary kiln for that particular granulometry that is mainly marketed, firing conditions- temperature, time, exhaust gas flow data, fuel consumption per tonne, loss of calcination, final classification, etc.

The product was evaluated in laboratory by the French Geological Institute BRGM compared to Diatomites from Denmark and China as well as absorbents from Atambuglite and Montmorillonite according to applicable specifications. The result of the comparison as shown by the relevant BRGM table proves that only the Chinese Diatomite outperforms in absorbency to the Greek one which outperforms all others.

BRGM report (1)

BRGM report (2)

Announcement for the company clay diatomites was made at the International Conference on Industrial Minerals in Athens in 2008 by G.Georgiadis, M. Stamataki, K. Hatziharalambous. In conclusion from the two area of use investigated (a) Thermo-sound insulating components, lightweight aggregate (LWA) (b) Industrial absorbents, it appears that the first sector with today’s high energy price data relative to similar end- product prices on the world market, cannot be a viable investment.

On the contrary, the creation of an absorbent unit due to the much higher end product price in comparison with the sector (a) and almost equal energy consumption (both being firing at around 800C – other processes approximately cost- equivalent), is considered perfectly viable given the excellent quality of the product produced on a semi-industrial scale.

Research was also conducted at LAVIOSA Italian company on how to use the material as a cat litter. The results (see table) were acceptable, except the clumping which can be neutralized by micropeletizing. The company plans to set up a micropeletizing unit a cat litter mixture of diatomite-zeolite as well as ultrafine zeolite micropeletizing with additives.

Scoreboard for the use of the Greek Diatomite of the company OLYMPUS SA as a cat litter.

DIATOMITE
DATA / DATE 25-08-11
PRODOTTO / PRODUCT NAME diatomite grecia
COLORE / COLOR beige
UMIDITA (%) / MOISTURE (%) 6,65
DENSITÀ APP. / DENSITY 0,427
ASSORBIMENTO / ABSORBTION 120
ATTRITION (%) / ATTRITION 12,91
CLUMPING / CLUMPING NO
RILASCIO NH3 (ppm) / NH3 RELEASE 10
GRANULOMETRY DISTRIBUTION 4,75 0,00
2,36 51,79
0,5 << 0,85 46,61
FONDO 1,60

Due to the circumstances, investment for the creation of an absorbent unit was not possible. For this reason, the company recently turned to producing a product useful to agriculture (component of soil conditioners as a source of amorphous silicon dioxide). This was made possible by the ability of the company now to produce ultra-fine products in size below 20 microns.

At the same time, deagglomeration-air separation-filtering research conducted in industrial scale in order to obtain a concentration in diatoms has resulted in a fraction with 75% diatoms (rest clays-aluminosilicates and very small percentage quartz according XRD determination)

The above research continue in order to obtain higher percentage of diatoms with lower impurities
In the electronic microscope photos taken by CERTH Centre for Research & Technology Hellas in specimens in various scales it is obvious  the concentration in diatoms by air separation.

Initial Stage of Research

In this way, would be possible to produce a product useful for insecticides, for agricultural preparations as a source of ultra-fine amorphous silicon dioxide (Diatoms), as ultra-fine filler -20μ for various industrial applications where ultra-fine amorphous silicon dioxide is required.

Concerning the use as an insecticide, the relevant tests were carried out in Canada by Diatomite Institute (in non concentrated material) and concerned the use of fighting the grown-up walking insects in cereal silos.

Tests Detachment of various categories of Greek Diatomite in relation to an MN51(a well known product of the market) as reference sample on insects mortality commonly occurring within silo cereals (sitophilus ozyzae, Tribolium castaneum) are shown in the accompanying table. Granulometry of the produced -20μ product shown on the LASER granulometry table of CERTH .

At the time being the tests for use as insecticide (in concentrated material) continue in the Entomology Lab of University of Thessaly funded by OLYMPUS in accordance a contract with the University.

The material for the tests is much more concentrated using a method compining heat and air flow (advanced stage of research the Diatomite content of this product is 76% according XRD of University of Athens (see photo below). The research continue.

Concentrated material after recent research

Pozzolan of Pella Prefecture

After the initial localization, the Pella’s Pozzolans met the needs of Cement Plant TITAN SA in Thessaloniki for more than four decades confirming their quality as a raw material for cement production.
OLYMPUS SA produces pozzolan -45μ ( crushing, drying, grinding at Pebble Mill and Air Separation) for the needs of the Archaeological Services as cement substitute and for Roman Concrete applications in some traditional buildings.

After the installation of high-speed air separator and the necessary filter, OLYMPUS SA also produces superfine pozzolan (-20μ and -10μ) for special uses. The hyper-milled superfine pozzolan -10μ and-20μ of OLYMPUS SA (see LASER granulometry – in comparison with known Super-pozz) is suitable for specialized uses such as special cement putty for precision seals, dam repairs, tunnels, drainage systems and general microcrack seals for soil sealing (www.usgrout.com)

The pozzolanic reaction ability (Binding capacity of Ca(OH)2) increases in proportion to the specific surface area and inversely proportional to the grain size.
The use of superfine pozzolans is recommended for the prevention of cracks in cement concrete due to binding of Ca(OH)2 created during cement hydration .

Also, the use of superfine pozzolans is recommended for self-leveling floor screeds and self- compacting concrete.

The monitoring of the granulometry of superfine as well as the -45μ products using LASER carried out by EKETA (CERTH -Centre for Research and Technology Hellas) in Thermi Thessaloniki.

It is noted that while there are several units of ultra- fine soft materials (calcium carbonate, etc.), the OLYMPUS SA unit is the only one capable of producing superfine hard minerals (>6Mohs).

 

Pozzolan Quarry

SuperPozz compared to fly ash and Silica fume

Zeolite

The best known area in Greece where there are good quality of zeolite tuffs is the North part of the prefecture of Evros. These formations also extend to the Bulgarian territory, where they are exploited by a multinational company. On the Greek territory, the only small-scale operation was near the village of Pentalofos of North Evros by a Greek company, but for 15 year it has ceased operation of the quarry and its activity transferred to Bulgaria, where it is continued by a multinational successor, according to the above.

Another attempt by a Hellenic Company to exploit the area’s zeolitic deposits resulted in a long-running legal dispute over the acquisition of licence. Noteworthy is the long, extensive and successful laboratory-scale research on the Greek zeolites, conducted by Professor of Geology at the Aristotle University of Thessaloniki, Mr. A. Filippidis.

OLYMPUS SA, after extensive geological exploration of the area, identified another area of interest for which obtained an Industrial Mineral Research License. The site was subsequently leased and licensed for exploitation on an area of 84 acres located in Kokkalo position, northwest of the settlement of Petrota. Based on YPEKA-approved technical study, a 1450-meter- long road was constructed, which covered most of the area of interest.

Photo in the electronic microscope (X4000) Zeolite (Clinoptilolite).

The purpose of the opening of the above road was to access research excavations and the research coverage of the site.

The results of the above exploration were very positive with the detection of zeolite deposit, at least 6m thick and 200m length. This layer was confirmed by both research excavations and cross-sections at different levels.

Α 1:1000 geological- mineralogical map survey was carried out on topographic background, on the basis of which a dense field sampling network was developed.

These samples were sent to specialized laboratories to USA and UK {(The Mineral Lab- COLORADO(XRD), Hazen Research Inc-COLORADO (CEC), Intertek Wilton UK (ICP_MS)} and others. The above laboratories performed mineralogical and chemical analyzes as well as ion exchange capacity (CEC). The results of the above analyzes were positive (clinoptilolite content ranged from 80% to 86%)

In addition to the laboratory research, a representative quantity was transferred from various locations of the field to study the processing on an industrial scale at the company’s plant in Assiros Thessaloniki.

This study produced test quantities of various grain sizes, in the area of granules (1-3mm,3-5mm etc.) and fine milling (D90=20μ and D90=45μ). The products thus produced were marketed with absolutely satisfactory results in use.

From February 2017 OLYMPUS SA holds an Exploitation License from the Ministry of Environment & Energy (Α.Π ΔΜΕΒΟ-Β/Φ6.11.7/171440/315/20-02-2017 with ΑΔΑ: ΩΙ704653Π8-ΕΟ8) following the lease preceded by the Decentralized Administration of Macedonia and Thrace. The mining activity developed in three separate positions of the zeolite field, within the licensed quarry area of 83,4273 acre

In November 2017 OLYMPUS SA carried out a research drilling program of the licensed site that holds in Kokkalo area. OLYMPUS SA is the only company that conducts a drilling research program to identify zeolite deposits in the North Evros area since so far (November 2017). No drilling for substantial Zeolite research has been carried out in North Evros by any other operator. The program that was executed included core drilling 220m totally (between 21m and 52m each drillhole).

The results was find a second layer (6m thick) in parallel and below the previously known layer which also confirmed.

Subsequently representative samples from the cores were sent to a USA accredited laboratory for mineralogical and chemical analysis as well as determination of physical characteristics to fully investigate the quality of the identified zeolite deposits. The results of these analyses are quite satisfactory.

Dry Graded Pumice Stone

Finding out the lack in the market of dry and graded pumice stone of various granular fractions, but also of milled (-45μ) OLYMPUS SA already offers the above products, with pumice stone raw material from Yali of Nisyros island, for construction purposes and other large number of known uses of graded pumice stone, the main of which are the treatment of drinking water, the purification of waste water, the pretreatment for reverse osmosis during desalination of marine water (SWRO), for filtering in fish farms, as a source of SiO2 in agricultural preparations, cosmetics, etc.

Especially for the paint industry and also as a filler-extender for rubber compositions, OLYMPUS SA offers the size of -20μ.

Concerning the construction sector, very interesting research has been carried out at the Aristotle University of Thessaloniki, Building Materials Laboratory, the main conclusions of which are listed below.

  • Testing as pozzolan according to ASTM C593-95 and EN 450-1 Standards with lime and cement replacement respectively.
  • Mortars with inert material, inert pumice in which a 10% was replaced with silica sand (0-1mm) and the rest mix cement CEM42,5+25% pumice powder.

The grain sizes available on request are:

In powder form In granular form
0 – 200 μ 0,1 – 0,3 mm
-45 μ 0,1 – 0,4 mm
-20 μ 0,2 – 0,5 mm
0,4 – 1,0 mm
0,8 – 1,3 mm
1,2 – 2,4 mm
2,0 – 3,5 mm

Test according to ASTM C593-95 of cement as lime pozzolan

Composition Test Bending Resistance σK Compressive Resistance σθ
SAMPLE TIME (MPa) (MPa)
Pumice 7 days 0,820 8,5
Pumice (α) 28 days 2,820 9,3
Pumice (β) 28 days 2,830 9,2

 

Required Strength ASTM C593-95
7 days 4,1 MPa
28 days 4,1 MPa

Photo 3,4: Bending and compressive strength charts

Testing of cement as pozzolan with cement according to EN 450-1 Standard

Composition Test Bending Resistance σΚ Compressive Resistance σθ
Reference 7 days 7,39 19,72
Pumice 7 days 6,55 19,70
Reference 28 days 7,31 25,30
Pumice 28 days 8,90 30,30
Reference 90 days 7,39 32,80
Pumice 90 days 7,06 25,64

Photo 4,5: Bending and compressive strength charts

Pumice composition as inert
Mix Cement Pumice Sand(0-1) Water Expansion
gr gr gr ml cm
mix1 1500 450 50 270 16

 

Pumice composition as powder and inert
Mix Cement Pumice (powder) Pumice (inert) Sand (0-1) Water Expansion
gr gr gr gr ml cm
mix2 450 150 540 60 300 16

 

Composition Test σKΜΟ σΘ
SAMPLE TIME (MPa) (MPa)
mix1 7 days 4,263 34,078
mix2 7 days 3,695 31,118
mix1 28 days 4,125 28,470
mix2 28 days 3,709 40,439

Finally, about the mortars with thermal and sound insulating properties should be mentioned Hess’s LimeStrong which has enormous expansion in the USA (www.limestrongfinish.com). It is a simple mixture of finely ground pumice+lime+water without cement, applicable for external insulation plaster with low cost and ability to add color and choice of texture (coarse, fine).

Beyond the fine milled pumice (-45μ) which react with hydrated lime, pumice in coarser granulometry 0-2mm participates as inert to the above mortar.