Method of using granular pyrolytic carbon for soil improvement

Abstract

The present invention has a density of 1.6 to 2.3 g / cc and a density of 0.001 to 5 m 2 The present invention also includes a method for using granular pyrolytic carbon having a specific surface area of ​​10 ...

Description

Technical Field

[0001] The present invention includes a method of using granular pyrolytic carbon having a density of 1.6 to 2.3 g / cc, a specific surface area of 0.001 to 5 m 2 / g, a particle size of 0.3 mm (d10) to 8 mm (d90), and a carbon content of 95 to 100% by mass for soil improvement, for example, to promote plant growth, to promote soil drainage, and to prevent erosion, evaporation, capping, crust formation, and sediment deposition. The pyrolytic carbon is preferably used as a mulching material.

Background Art

[0002] Soil is the most important production factor for farmers, and thus preventing erosion, evaporation, and sediment deposition is a central task for farmers. Mulching materials are currently used to prevent erosion, evaporation, weed control, and depletion of humus. Generally, plant residues of intercrops or straw of the previous crop are used as mulching materials.

[0003] The drawback of mulching materials is that lumps of organic matter bind to active ingredients such as herbicides, weakening their effects. Also, multiple sowings are time-consuming and costly.

[0004] In addition to multiple sowings, compost may be spread on the fields. Depending on the type of compost, the bad smell may last for several days.

[0005] US 2,877,599 discloses that carbon black having a high volume relative to its mass can be incorporated into soil to darken the soil and improve heating by solar radiation and water absorption and retention. US 2,877,599 discloses that carbon black is very light and fluffy (aggregate size 85 - 500 nm, aggregates 1 - 100 μm, density 1.7 - 1.9 g / cm3) and is in a sense very volatile, so it cannot be deposited directly on the ground. Just dropping it, a significant proportion of the carbon black "evaporates" into the air and the rest is quickly blown away by the wind or drifts. US 2,877,599 concludes that it is substantially impossible to directly add carbon black to the soil. Therefore, US 2,877,599 discloses a soil improver in the form of compact pellets containing 5 - 40%, preferably 10 - 20%, of carbon black, up to 50% of gypsum, up to 1% of binder, and up to 95% of organic fiber material, such as sewage sludge from a sewage treatment plant, waste liquor from a paper mill or humus soil. This soil improver can be spread on the soil in an amount of 200 pounds (90 kg) to 2 tons per acre (0.405 hectares). It is desirable to incorporate this soil improver into the ground to a depth of 2 inches over a period of 2 years. The pellets have a diameter and length in the range of 1 / 4 to 3 / 16 inch.

[0006] US 3,345,773 discloses a method of using a carbonaceous solid having a diameter of 0.08 inch to 0.5 inch as a mulching material to promote plant germination and growth by warming the soil, preventing soil crust formation, and retaining moisture in the soil. Various useful carbon solids are described, such as coal, for example lignite, anthracite, bituminous coal, coke derived from coal and coke derived from petroleum. The carbon solid is composed mainly of carbon having less than about 25% by mass of volatile matter and is defined to include solids obtained from coal or petroleum sources. This mulching material is applied on the solid to provide a layer over the seeds having a thickness of 0.125 inch to 1.5 inches. Preferably, the carbonaceous solid is mixed with a water-impermeable material to provide a water barrier.

[0007] US 3,341,318 discloses a multi - composition containing lignin sulfonate composition, carbon black and water, which are by - products of the paper - making industry. These multi - compositions bring about an increase in soil temperature, and as a result, ensure better germination, earlier emergence and earlier maturity of crop seeds, conserve soil moisture, reduce soil loss by wind, can be easily sprayed without clogging applicator nozzles, and are non - corrosive to application devices. When the main purpose is the weeding effect, carbon black can be optionally omitted from the mulching material.

[0008] JP 9310068 relates to a soil improver containing a carbon material having a high specific surface area of 30 - 500 m / g, which is composed of combustion residues of waste rubber products.

[0009] Carbon sources of unknown composition, i.e., carbon - containing waste, are potentially dangerous because they may contain environmentally harmful or toxic components. Environmental protection regulations require that soil additives such as soil improvers be safe and not add pollutants to the soil.

[0010] In view of the unknown components using waste, WO 2012 / 15313 discloses a manufacturing system for soil improvers that supplies a gaseous hydrocarbon source to a plasma cracking unit and supplies the produced plasma carbon to a unit for mixing with a base material to produce a carbon - enriched soil improver. The base material to be mixed with carbon can be different soil types such as sand, clay or organic waste. Plasma carbon having small nodule sizes (less than 100 nm) has been disclosed to have several advantages as a soil improver because it absorbs ultraviolet light and protects microorganisms, which are essential for good growth conditions of soil exposed to strong sunlight. WO 2012 / 15313 has a range of 50 - 1000 m 2It is disclosed that the large surface area of / g is important for improving water retention and thus preventing soil dehydration. In addition to the drawbacks of the efforts to pelletize carbon black, WO 2012 / 15313 discloses that substrates based on carbon black have a continuing tendency to form dust. However, dust promotes erosion and depletion of humus, and environmental protection regulations require that soil additives be used in a form surrounded by dust.

[0011] The use of carbon as a soil improver has a long history in the literature, but it is not known to be widely used.

[0012] In recent years, from the perspectives of humus depletion, climate change and organic waste treatment, biochar has attracted attention as a promising soil improver.

[0013] The advantages of biochar are said to be mainly three: soil improvement, N2O reduction, and C sequestration. The large surface area of biochar is thought to lead to long-term water storage, the functional groups bind nutrients, and the black color improves the heat retention of the soil. Changes in the physical habitat of the soil can lead to changes in the microbial community and potentially suppress the emission of N2O. The polycyclic aromatics of biochar decompose more slowly than the original biomass, which is a carbon sink.

[0014] However, most of the recent studies have only shown that the effect on crop yields is small or not significant (Martin Bach, Burkhard Wilske & Lutz Breuer (2016): Current economic barriers to the use of biochar in agriculture and climate change mitigation, Carbon Management, DOI: 10.1080 / 17583004.2016.1213608; Steffens (2019), Bring Carbon into the Soil. Lumbrico 3, 36 - 39; Borchard, N., Siemens, J., Ladd, B., Moeller, A., Amelung, W. (2014) Application of biochar to sandy and silty soils did not increase maize yields under common farming practices, Soil and Tillage Research 144, 184 - 194).

[0015] The average cost of biochar is currently about 400 euros per ton. When about 10 tons / ha are used, the profit from increased yields is estimated to be 1 - 10 euros per ton per year. The estimated median half - life of biochar is 20 years, and large - scale use of biochar in agriculture is not yet profitable (see Bach, Muell und Abfall (2017); BUND (2015), Terra Preta / Pyrolysekohle - BUND Einschaetzung ihrer Umweltrelevanz). Furthermore, it is questionable whether the potentially available biochar per year can meet the market demand.

[0016] Therefore, considering the current cost of biochar, its economic viability does not recommend general use in crop production. Furthermore, the conversion process from biomass to pyrolysis biochar must also be critically evaluated regarding the pollutant (especially PAH) content in the product.

[0017] US 2013 / 312472 discloses a composition containing pyrolyzed biomass for use in soil improvement. The pyrolyzed biomass may contain more than 95% by mass of carbon and be a granular composition having a particle size of 1 mm. US 2013 / 312472 describes that due to its high porosity, nutrients and microorganisms accumulate in the biochar, and plants can grow even in highly porous soil. The BET surface area determined at a pyrolysis temperature of 600 - 750 °C for wood, straw, food waste and algae ranges from 20 to 200 m2 / g.

[0018] US 8 361 186 discloses that biomass materials can be pyrolyzed and such granular pyrolyzed carbon can be used as a soil improvement material. It is disclosed that the carbon content ranges from 10 to 99.5% by mass and the surface area ranges from 1 to 5000 m2 / g.

[0019] US 2019 / 002764 also discloses the use of pyrolyzed and surface - oxygenated biochar with optimized hydrophilicity as a soil improvement substrate. The substrate is in granular form with a maximum particle size of 3 mm, the carbon content ranges from 65 to 75% by mass, and the surface area ranges from 0.1 to 800 m2 / g.

[0020] Kathrin Weber and Peter Quicker analyzed many biochar samples in Fuel 217 (2018) 240 - 261. The carbon content ranges from 50 to 95% by mass, the density of the biochar ranges from 0.4 to 0.75 g / cc, the bulk density is about 0.3 g / cc, the BET ranges from 1 to 700 m2 / g, the total pore volume ranges from 1 to 4.8 cm3 / g, and all parameters depend on the pyrolysis temperature.

[0021] A common method to promote seed germination and plant growth is to cover with black foil. However, its drawbacks such as water impermeability, using microplastics, being a time - consuming and costly method, and having an adverse impact on the landscape are well - known.

[0022] Considering the increasing risk of heavy rain due to climate change in addition to the problems of soil erosion and evaporation, water infiltration and capping are major issues. Capping means that soil particles on the soil surface move due to raindrops or generally the movement of water. Due to the impact of raindrops (hail, heavy rain, continuous rain, irrigation), soil aggregates are more or less mechanically pulverized, and fine particles or single particles are removed. The results of capping are as follows: (i) flattening, which accelerates surface runoff; (ii) closing of soil pores, which reduces the amount of water absorbed (infiltration amount); and (iii) crust formation after drying, which prevents germinating plants from emerging from the soil surface.

Prior Art Documents

Patent Documents

[0023]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Patent Document 6

Patent Document 7

Patent Document 8

Non-Patent Documents

[0024]

Non-Patent Document 1

[0025] An object of the present invention is to provide a method for promoting plant growth.

[0026] A further object of the present invention is to provide a method for promoting plant growth by reducing erosion by wind and / or rain.

[0027] A further object of the present invention is to provide a method for promoting plant growth by reducing moisture loss to the atmosphere and thereby providing a high moisture content in the soil.

[0028] Furthermore, a further object of the present invention is to provide a method for promoting plant growth by increasing the radiative heat absorption of the seedbed, reducing the need for irrigation, reducing the risk of capping, crust formation, sediment deposition, and / or suppressing weed growth.

[0029] A further object of the present invention is to provide a soil conditioner that is dust-free or dustless, odorless, and can be temporarily stored externally.

[0030] A further object of the present invention is to provide a soil conditioner that is easy to handle and has a narrow particle size distribution, enabling accurate dosing.

[0031] A further object of the present invention is to provide a soil conditioner that does not contain contaminants and is not harmful to the soil and plants even in large amounts.

[0032] A further object of the present invention is to provide a carbon-containing soil conditioner that is not biodegradable and thus does not emit carbon dioxide.

[0033] A further object of the present invention is to provide a soil conditioner that can replace biochar and is available at a reasonable price in an amount sufficient to meet market demand.

Means for Solving the Problems

[0034] The present invention provides a granular pyrolytic carbon-containing soil conditioning substrate having a density of 1.6 to 2.3 g / cc, a specific surface area of 0.001 to 5 m 2 / g, a particle size of 0.3 mm (d10) to 8 mm (d90), and a carbon content of 95 to 100% by mass.

[0035] This particle size is of the same order as that of fine gravel (usually 2 - 6 mm) or coarse sand (usually 0.5 - 2 mm).

[0036] The present invention provides a method for promoting the growth of plants in soil, which includes applying granular pyrolytic carbon having a particle size of 0.3 - 8 mm and a carbon content of 95 - 100% to the soil.

[0037] Further, the present invention provides a method of directly using granular pyrolytic carbon as a soil conditioner for agricultural land and / or horticulture without passing through a pelletizing process. Preferably, in addition to mulching seeds, granular pyrolytic carbon is used.

Brief Description of the Drawings

[0038]

Figure 1

Figure 2a

Figure 2b

Figure 2c

Figure 2d

Figure 2e

Figure 3

Embodiments for Carrying Out the Invention

[0039] Pyrolytic carbon The term "pyrolytic carbon" refers to solid carbon produced by the pyrolysis of light hydrocarbons in the absence of oxygen (see, for example, Muradov, Nazim. "Low to near-zero CO2 production of hydrogen from fossil fuels: Status and perspectives." International Journal of Hydrogen Energy 42.20 (2017): 14058-14088). Preferred granular pyrolytic carbon is a high-density solid elemental carbon produced by deposition onto carbon granules. Thermally produced black by a thermal / plasma process, or nanostructured carbon grown on a metal / oxide catalyst is preferred.

[0040] Pyrolytic carbon can preferably be produced by the decomposition of gaseous hydrocarbon compounds, preferably methane, and carbon deposition onto a suitable underlying substrate (carbon material, metal, ceramic, and mixtures thereof) at a temperature in the range of 1000 to 2500 K and a pressure in the range of 0.5 to 5000 kPa (abs). The substrate can be either porous or non-porous and can be either a carrier substrate (pre-attached component) within the reactor or a granular powdered material. When using a catalyst-active metal-containing carrier, such a metal preferably has a positive interaction with the germination of seeds and the growth of plants or has no interaction at all and can remain in the soil like iron. A preferred substrate is a carbon-containing substrate, such as pyrolytic carbon, which means carbon obtained from the oxygen-free pyrolysis of hydrocarbons in the presence of a carbide deposition substrate at a temperature above 1000 °C. The particle size of the preferred carrier substrate ranges from 0.3 to 8 mm, preferably from 0.5 to 5 mm, more preferably from 1 to 4 mm. The decomposition can be realized as either a fixed bed, moving bed, fluidized bed, or entrained flow. The production of pyrolytic carbon is not limited to a specific energy supply, and fossil fuel, electric heating, or plasma-driven production reactors can be used.

[0041] In pyrolytic carbon, a wide range of microstructures can occur depending on the deposition conditions (temperature, type, concentration and flow rate of the source gas, surface area of the substrate, etc.), such as isotropic, layered, substrate nuclei, and various contents of residual hydrogen.

[0042] Typically, the density of pyrolytic carbon ranges from 1.5 to 2.5 g / cc, 1.6 to 2.3 g / cc, preferably from 1.8 to 2.2 g / cc, more preferably from 1.9 to 2.15 g / cc (true density in xylene, ISO8004). Typically, the bulk density of pyrolytic carbon ranges from 0.5 to 1.5 g / cc, preferably from 0.6 to 1.3 g / cc, more preferably from 0.7 to 1.1 g / cc.

[0043] Typically, the carbon content of pyrolytic carbon ranges from 95 to 100 mass%, preferably from 98 to 100 mass%, more preferably from 99 to 100 mass%, even more preferably from 99.5 to 100 mass%, even more preferably from 99.75 to 100 mass%, even more preferably from 99.9 to 100 mass%. Typically, the impurities in pyrolytic carbon are as follows: S in the range of 0 to 1 mass%, preferably 0 to 0.5 mass%, more preferably 0 to 0.1 mass%; Fe in the range of 0 to 1000 ppm, preferably 0 to 500 ppm; Ni in the range of 0 to 250 ppm, preferably 0 to 100 ppm; V in the range of 0 to 450 ppm, preferably 0 to 250 ppm, more preferably 0 to 100 ppm; Na in the range of 0 to 200 ppm, preferably 0 to 100 ppm. Oxygen is in the range of 0 to 100 ppm, preferably below the detection limit.

[0044] Typically, the particle size of granular pyrolytic carbon directly obtained from the decomposition of gaseous hydrocarbon compounds ranges from 0.3 mm (d10) to 8 mm (d90), preferably from 0.5 mm (d10) to 5 mm (d90), more preferably from 1 mm (d10) to 4 mm (d90).

[0045] The proportion of particles with a particle size of 0.1 mm or less, preferably 10 μm or less, more preferably 5 μm or less is at most 20 mass ppm, more preferably at most 10 mass ppm. The proportion of particles with a particle size of 0.1 mm or less, preferably 10 μm or less, more preferably 5 μm or less is in the range of 0 to 20 mass ppm, preferably 0 to 10 mass ppm.

[0046] Optionally, the granular pyrolytic carbon directly obtained from the decomposition of the gaseous hydrocarbon compound can be classified into a desired particle size or a desired particle size distribution if required for a specific agricultural use. Multifaceted classifiers are commonly used for such separation / classification processes.

[0047] Typically, the crystal size (XRD) of the pyrolytic carbon is in the range of 20 to 60 Å, preferably 30 to 50 Å (XRD, ISO 20203).

[0048] Typically, the porosity of the pyrolytic carbon particles is 0% to 15%, preferably 0.2% to 10%, most preferably 0.2% to 5% (Hg porosimetry, DIN66133).

[0049] Typically, the specific surface area of the pyrolytic carbon measured by Hg porosimetry (DIN66133) is 0.001 to 10 m 2 / g, preferably 0.001 to 5 m 2 / g, more preferably 0.01 to 2 m 2 / g, even more preferably 0.05 to 2 m 2 / g.

[0050] The pyrolytic carbon is preferably a hydrophobic material having a preferred contact angle of water droplets greater than 70, preferably greater than 80, more preferably greater than 90.

[0051] Typically, the granular pyrolytic carbon produced by the decomposition of the gaseous hydrocarbon compound and the carbon deposition on a suitable underlying substrate does not tend to form dust.

[0052] Preferably, the granular pyrolytic carbon produced by the decomposition of the gaseous hydrocarbon compound and the carbon deposition on a suitable underlying substrate can be used directly as a soil conditioner. Preferably, a pelletizing step is not necessary. Preferably, it is not necessary to add a binder, a filler, etc.

[0053] Application of Granular Pyrolytic Carbon The soil conditioner can be spread or applied to agricultural land (soil) in an amount in the range of 0.5 to 500 tons, preferably 2 to 200 tons, more preferably 5 to 20 tons per hectare.

[0054] Preferably, the thickness of the soil conditioner layer laid on the seedbed can vary according to general planting conditions such as the water content of the soil and the type of plant to be planted.

[0055] Generally, a soil conditioner layer thickness of 0.5 mm to 50 mm, preferably 1 mm to 20 mm, most preferably 5 mm to 15 mm can be used.

[0056] Because of such a granular form, the soil conditioner can be easily applied and incorporated into the soil. The soil conditioner can be deposited with a well-known spreader, such as a fertilizer spreader, and can be pushed or pulled by hand, or pulled by a tractor. Optionally, the soil conditioner can be incorporated into the topsoil layer with a soil tillage device, or the soil conditioner can be left on the soil surface.

[0057] Optionally, the soil improvement base material of the present invention can be applied as a layer on the soil after the seeds are planted. The advantage of applying after the seeds are planted is to avoid the granular pyrolytic carbon layer being destroyed by subsequent seeding operations.

[0058] The soil conditioner can be applied as a single layer over the entire seedbed, or alternatively, as a narrow band covering only the seeded rows. In another embodiment, the soil conditioner can be applied as a periodic or discontinuous band over the seed rows to facilitate thinning operations.

[0059] Optionally, the soil improvement base material can be mixed with other commonly used soil improvement base materials, such as fertilizers, liming materials, commonly known soil improvement materials, cultivation media, inhibitors and / or plant biostimulants regulated by Regulation (EU) 2019 / 1009, and applied as a mixture. Optionally, the particle size of the soil conditioning base material can be adapted to the co-conditioning base material, for example by classification.

[0060] Optionally, the soil conditioning base material of the present invention can carry pesticidal active substances from the group of different organic or inorganic additives, such as fungicides, bactericides, herbicides and / or plant growth regulators.

[0061] Advantages Here, a soil improvement material that is dust-free, odorless, and easy to handle and apply has been discovered. The carbon produced by the decomposition of gaseous hydrocarbon compounds can be directly used as a soil improvement material without a pelletizing process.

[0062] The soil improvement material of the present invention can be used as a mulching material for the surface layer and does not need to be incorporated into the soil.

[0063] Furthermore, the carbon-containing soil improvement material can remain in the soil without being converted into carbon dioxide.

[0064] Furthermore, the soil improvement material of the present invention can reduce soil erosion by wind. Furthermore, the soil improvement material of the present invention used as a mulching material can reduce water loss from the soil to the atmosphere, and as a result, maintain a high water content in the soil. Although disclosed in WO 2012 / 15313, this effect of maintaining a high water content in the soil could not be measured with carbon black as a soil improvement material at the same application rate (e.g., 16 t / ha).

[0065] The soil improvement material of the present invention exhibits good water permeability and capping properties, as well as a good hydraulic conductivity of the soil.

[0066] The soil improver of the present invention can meet the market demand. In a small-scale hydrogen production plant, methane pyrolysis is used to typically produce 10,000 Nm3 / h of hydrogen, and 21,400 t / a of pyrolytic carbon can be produced as a by-product. In a medium-scale hydrogen production plant, typically 50,000 Nm3 / h is produced, and thus 107,000 t / a of pyrolytic carbon is produced as a by-product. In a large-scale hydrogen production plant, usually 100,000 Nm3 / h is produced, and thus 214,000 t / a of pyrolytic carbon is produced as a by-product.

Example

[0067] 1 Comparison between pyrolytic carbon and biochar Properties: In the experiment, granular pyrolytic carbon and biochar were tested.

[0068]

Table 1

[0069] Granular pyrolytic carbon is produced by decomposing natural gas and depositing it on a fluidized bed on a calcined petroleum coke carrier material (a carrier having a particle size of 0.5 to 2.5 mm, a sulfur content of 1.1% by mass, and a true density in xylene of 2.09 g / cm3) at a temperature of 1100 to 1300 °C and a pressure of 1 to 2 bar (abs).

[0070] BET: Measured by the method described in DIN ISO 9277.

[0071] Density: The specific gravity (density) was determined by the principle of Archimedes in pure water (see Wikipedia). When the specific gravity is 1 g / cc or more, in order for hydrophobic particles to also sink in water, a part of the experiment was carried out in water improved with a wetting agent to lower the surface tension of water.

[0072] Bulk density: ASTM C559 "Standard Test Method for Bulk Density by Physical Measurement of Manufactured Carbon and Graphite Articles".

[0073] SEM (see Figure 2): Platinum vapor was sprayed onto samples of pyrolytic carbon and biochar, and photographs were taken with a Zeiss Gemini SEM 500 scanning electron microscope.

[0074] 2 Erosion Experimental setup: A wind tunnel with a wind speed gradient of different wind speeds from 0 km / h to 7 km / h was installed (measured with a Lechler Pocketwind IV Hand Aerometer placed on an inverted Petri dish, and materials (pyrolytic carbon, carbon black, biochar 1, dry biochar 4) were also applied on the inverted Petri dish).

[0075] 2.1 Wind speed An inverted Petri dish with 1.5 g of the material was placed in the wind tunnel, and the wind speed was increased.

[0076] [Table 2]

[0077] 2.2 Material loss An inverted Petri dish with 1.5 g of the material was placed in the wind tunnel at a wind speed of 6.4 km / h. After exposing it to the wind for 5 minutes, the mass of the material remaining in the Petri dish was measured.

[0078] [Table 3]

[0079] Covering the topsoil with pyrolytic carbon or carbon black reduced the impact of wind erosion due to its high density and small surface area. Biochar, with its low density and structured surface with a large surface area, provides more contact surfaces with the wind under dry conditions.

[0080] 3 Comparison between pyrolytic carbon and carbon black Properties: In the experiment, granular pyrolytic carbon and carbon black were tested.

[0081]

Table 4

[0082] The granular pyrolytic carbon is produced by decomposing natural gas and depositing it in a fluidized bed on a calcined petroleum coke carrier material (having a particle size of 0.5 - 2.5 mm, a sulfur content of 1.1% by mass, and a true density in xylene of 2.09 g / cm3) at a temperature of 1100 - 1300 °C and a pressure of 1 - 2 bar (abs).

[0083] 3.1 Formation of Biomass Application method (see Figure 1) and test method Pot experiment using corn: Using soil Limburgerhof (loamy sand, pH 6.8), it was placed in a "Mitscherlich pot" (each pot contains 6.4 kg of dry soil). In each pot, 99 mg of Mg as MgSO 4 , 0.436 g of P as K2HPO4 and 1.1 g of K, and 1 g of N as NH 4 NO 3 were given as basal fertilizers.

[0084] The carbon sample was uniformly mixed with the soil (application, treatment A), uniformly mixed with 1 kg of soil on top of 5.4 kg of other soil without addition (application B), or the carbon sample was placed on top of the soil 9 days after the sown corn germinated (application C) (see Figure 1).

[0085] 314 cm 2 For each pot having a soil surface area of, 2, 4, 8, 16 t of C / ha correspond to 6.3, 12.5, 25, 50 g of C / pot respectively.

[0086] Six seeds of Zea mays (L.) cv. "Amadeo" were sown per pot (on June 5, 2019). After germination, first thinned to 3 plants per pot uniformly, and then thinned to 1 plant per pot and cultivated until maturity. As the second fertilization, NH 4 NO3 As the first application, 1 g of N was applied, and finally, as the third fertilization, 6.7 g of the compound fertilizer Nitrophoska® perfect (15 + 5 + 20S + 2 + 8 + trace elements) was applied to each pot on June 28th.

[0087] Each carbon treatment had 4 replicates, and the untreated control had a total of 8 replicates. The pots were placed completely randomly on the conveyor table in the Vegetation hall Limburgerhof and exposed to natural irradiation and air temperature from sowing to harvest. The functions and characteristics of the Vegetation hall Limburgerhof are described by Jung (1967).

[0088] From Monday to Friday, after measuring the soil moisture up to 70% of the maximum water retention capacity, the pots were watered semi - automatically twice a day (the mass difference of the pots due to the addition of carbon samples was considered as the extra mass). On Saturday and Sunday, without measuring the mass, the pots were watered horticulturally twice a day as needed.

[0089] Harvesting was carried out on October 2nd. The new shoots were separated into rachis and the remaining plants, and the plant biomass was dried to a constant mass in a forced oven at 80 °C, and then the total dry matter yield (Table 5) and rachis dry matter yield (Table 6) were determined.

[0090] Application A: Mixed uniformly with the entire soil of the plant pot (0 - 15 cm, 6.4 kg of soil), Application B: Mixed uniformly with only the topsoil (0 - 3 cm, 1 kg of soil), Application C: Applied as a mulching material on the upper part of the soil 9 days after germination.

[0091] 3.1.1 Application method (see Figure 1) and test method Figure 1: Treatment of soil with two carbon forms (pyrolytic carbon, carbon black) applied at different rates in different locations 3.1.2 Comparison of test results

[0092]

Table 5

[0093]

Table 6

[0094] Both the addition of pyrolytic carbon and the addition of carbon black increased the biomass production of maize in the range corresponding to 2 - 16 tons per hectare on average (Tables 5 and 6). The only exception was when the highest optimal dose of carbon black (16 t / ha) was applied only on the top of the topsoil or on the soil after plant germination (Applications B and C). In this case, no increase in dry matter was observed, or the growth decreased slightly on average. In contrast, when pyrolytic carbon was applied to the soil after germination at a rate of 8 or 16 t / ha, the total dry matter of new shoots increased by 13% on average (Table 5), and the dry matter of maize cob increased by 17% (Table 6), and both parameters were statistically significant (not shown in the table).

[0095] When uniformly spread on the soil (Application A), on average and statistically, carbon black promoted growth somewhat more than granular pyrolytic carbon within the range of application rates. When the two carbon sources were concentrated in the top 3 cm of the soil (Application B), or placed on the soil (Application C), the picture changed. In these cases, on average and statistically, pyrolytic carbon was superior to carbon black.

[0096] 3.3 Biodegradability Biodegradability was tested by measuring soil respiration after adding pyrolytic carbon and carbon black at an application rate of 313 mg per 50 g of soil (soil Limburgerhof, loamy sand, pH 6.8) corresponding to approximately 2 t of C / ha. Soils without addition or soils with 50 mg of ground wheat straw (0.32 t / ha) added to 50 g of soil were used as controls. Soil respiration was measured using a WTW OxiTop (Wilhelmshaven, Germany) placed in an incubator at 20 °C according to the methods outlined by Robertz et al. (1999) and Malkomes and Lemnitzer (2009).

[0097] In Table 7, wheat bran caused strong soil respiration, while carbon black did not cause higher CO 2 generation than the untreated soil (pyrolytic carbon was manually ground using a mortar and pestle until almost no particles were visible to the naked eye). No statistically significant trend was observed in the difference in soil respiration between carbon forms or in comparison with the untreated soil (not shown in the table).

[0098]

Table 7

[0099] 3.4 Tendency of dust formation The tendency of dust formation was measured by the Heubach test method (DIN 55992). 100 g of granular urea fertilizer (state of the art), granular pyrolytic carbon, and carbon black were compared.

[0100]

Table 8

[0101] Well-known granular urea was used as a control for dust formation. Compared with urea, pyrolytic carbon showed only about 30% of the dust formation, while carbon black showed more than 15 times the dust formation of urea when measured by the Heubach test method.

[0102] 3.5 Water storage capacity 500 g of air-dried soil Limburgerhof (composition: 73% sand, 24% silt, 3% clay, pH in CaCl 2 is 6.8) was moistened with 110 ml of demineralized water, covered with 16 t / ha (7.07 g) of pyrolytic carbon or carbon black, and treated in a beaker with an inner diameter of 7.5 cm at 21 - 22 °C and a relative humidity of 40 - 50%. Each treatment was repeated 3 times.

[0103]

Table 9

[0104]

Table 10

[0105] Tables 9 and 10 show that covering topsoil with pyrolytic carbon can reduce moisture loss to the atmosphere and ensure a high water content in the soil, while carbon black cannot significantly reduce moisture loss. As a result of this effect, the multi-layer of pyrolytic carbon increases the water content in the soil, making it available for the growth of more plants.

[0106] 3.6 Water Absorption Capacity First, the samples were dried. The air humidity was gradually increased in 10% steps from 0% to 90%, and the criterion for the next stage was a mass variation of less than 0.05% in 45 minutes.

[0107]

Table 11

[0108] Table 11 shows that carbon black and pyrolytic carbon have a lower water absorption rate because they have a smaller surface area and are hydrophobic compared to biochar.

[0109] Cited References Jung, J. (1967): Eine neue Vegetationshalle zur Durchfuehrung von Gefaessversuchen. Z. Acker - u. Pflanzenb. 126, 293 - 297. Malkomes, H.-P., Lemnitzer, B. (2009): "Comparison of substrate-induced short-term respiration measured by URAS and OxiTop Control in soil during microbiological ecotoxicological monitoring of plant protection products. I. Influence of a reference herbicide and a neutral salt", Nachrichtenblatt Deutscher Pflanzenschutzdienst, 60, 104-112. Robertz, M., Muckenheim, Th., Eckl, S., Webb, L. (1999): "Cost-effective laboratory method for determining microbial soil respiration according to DIN 19737", Wasser & Boden, 51 / 5, 48-53.

Claims

1. A soil conditioning base material containing granular pyrolytic carbon having a density of 1.6 to 2.3 g / cc, a specific surface area of 0.001 to 5 m ２ / g measured by Hg porosimetry, a particle size of 0.3 mm (d10) to 8 mm (d90), and a carbon content of 95 to 100% by mass.

2. The soil conditioning base material according to claim 1, wherein the granular pyrolytic carbon has a density of 1.8 to 2.2 g / cc.

3. The granular pyrolytic carbon has a specific surface area of 0.01 to 2 m ２ / g as measured by Hg porosimetry, and the soil conditioning base material according to claim 1 or 2.

4. The soil conditioning base material according to any one of claims 1 to 3, wherein the granular pyrolytic carbon has a bulk density of 0.5 to 1.5 g / cc.

5. The soil conditioning base material according to any one of claims 1 to 4, wherein the proportion of the particle size less than 5 μm is at most 10 mass ppm.

6. The soil conditioning base material according to any one of claims 1 to 5, wherein the granular pyrolytic carbon is a hydrophobic material having a contact angle of more than 70 for water droplets.

7. The soil conditioning base material according to any one of claims 1 to 6, which supports different organic or inorganic additives selected from the group consisting of fungicides, bactericides, herbicides and / or plant growth regulators.

8. The soil conditioning base material according to any one of claims 1 to 7, which contains mulching seeds.

9. A method for promoting plant growth in agricultural land, comprising applying granular pyrolytic carbon having a density of 1.6 to 2.3 g / cc, a specific surface area of 0.001 to 5 m ２ / g measured by Hg porosimetry, a particle size of 0.3 mm to 8 mm, and a carbon content of 95 to 100% by mass to the agricultural land.

10. The method according to claim 9, wherein the granular pyrolytic carbon is sprayed on the farmland in an amount in the range of 0.5 to 500 tons per hectare.

11. The method according to claim 9 or 10, wherein the initial thickness of the granular pyrolytic carbon layer in the farmland is in the range of 1 mm to 50 mm.

12. Granular pyrolytic carbon having a density of 1.6 to 2.3 g / cc, a specific surface area of 0.001 to 5 m ２ / g measured by Hg porosimetry, a particle size of 0.3 mm (d10) to 8 mm (d90), and a carbon content of 95 to 100 mass %, and a method for using the granular pyrolytic carbon as a soil conditioner for agricultural land and / or horticulture.

13. The method of use according to claim 12, wherein the granular pyrolytic carbon is used as a soil improver in addition to the mulching seeds.

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