Peat
Organic sedimentary rock
It is an organic sedimentary rock that is formed from the remains of marsh vegetation (lichens, reeds, sphagnum, etc.). Peat takes thousands of years to form (only 1 mm layer is formed per year) and is divided into fibrous and amorphous peat, and according to the conditions of formation – into formed in the lowland bogs, in the raised bogs and transitional kind of peat. Peat accumulates in swamps and marshy forests, where excess water collects. Peat is extracted by draining the wetlands. The excavated peat can then be recycled chemically or mechanically. There are almost forty of these rock types in Lithuania.
The products manufactured by Rėkyva JSC are made of milled and block peat formed in the raised bogs. In addition, peat is divided into different categories according to the degree of peat formation, each category has its own properties.
| Peat type | Uplands | Uplands | Uplands |
| Category | Block light | Fractal light | Fractal dark |
| Fragmentation | H1-H3 | H3-H4 | H4-H6 |
| Acidity pH (H2O 1:1) | 3,5 ‒ 4,5 | 4,2 ‒ 4,7 | 4,5 ‒ 5,0 |
| Organic matter % | >97 | >94 | >90 |
| Ash % | 1 – 5 | 2 – 7 | 3 – 8 |
| Bulk density at moisture 50% g/L | <200 | 200-240 | >240 |
| Electric wire mS/cm | <0,15 | <0,15 | <0,15 |
| Porosity % | 94 – 96 | 92 – 95 | 90–93 |
| Moisture % | 45 – 55 | 45 – 55 | 45 – 55 |
| Water absorption, sometimes | >9,0 | >7,5 | >6,0 |
| Absolute dry mass g/l | <100 | 100-120 | >120 |
WHAT IS THE DIFFERENCE BETWEEN MILLED AND BLOCK PEAT?
Milled peat
Milled peat is collected by vacuum suction – 1-2 cm thick layer of peat is extracted from the surface of the bog. Before collecting milled peat, 2 cm thick layer of peat torn from the stratum is turned over several times and dried. And, only after this, the peat is extracted with a special vacuum device and and piled into the stacks of about 2,000 cubic metres each. Later, the peat is transported from the piles to factories for the manufacturing and packaging of products. Milled peat extracted by this method contains more fine particles in comparison with block peat. Milled peat is subdivided into light and black. Main extracted fractions: 0-7 mm; 0-20 mm; 0-40 mm.
Block peat
Block peat is extracted by excavating rectangular pieces from the stratum of peat. They are laid on the surface of the peatland. The sun and wind dry the pieces of peat. These pieces of peat are then placed on special pallets and dried further until they become suitable for production. The biggest advantage of this method is the preservation of the peat structure, small quantity of fine particles. Main extracted fractions: 0-7 mm; 7-20 mm; 20-40 mm.