WO2025023847A1

WO2025023847A1 - Organic-mineral fertilizer

Info

Publication number: WO2025023847A1
Application number: PCT/PL2024/000038
Authority: WO
Inventors: Jean Bernard Diatta
Original assignee: Biostra Spolka Z Ograniczona Odpowiedzialnoscia
Current assignee: Biostra Spolka Z Ograniczona Odpowiedzialnoscia
Priority date: 2023-07-26
Filing date: 2024-07-18
Publication date: 2025-01-30
Anticipated expiration: 2026-01-26
Also published as: PL445680A1; PL247633B1

Abstract

The subject of the invention is an organic-mineral fertilizer produced on the basis of hygienized sewage sludge, stabilized with cereal straw, sawdust of coniferous and deciduous trees, calcium sulphate and calcium oxide. The organic-mineral fertilizer stabilized with cereal straw and calcium sulphate based on hygienized sewage sludge, calcium oxide, cereal straw, sawdust from coniferous and deciduous trees and calcium sulphate, contains 35-70 parts by weight (p.w.) preferably 65 p.w. of hygienized sewage sludge with 60-80% water content, preferably 75%, 5 - 15 p.w. preferably 5 p.w. of calcium oxide as a pH regulator, with water content <10%, preferably <5%, 10 - 25 p.w. preferably 15 p.w. of organic stabilizer, which is cereal straw with a particle size of 5.0 - 35.0 mm, preferably 10 mm, with a water content of 5 - 35%, preferably 30%, 25 - 58 p.w. of lignin-cellulose organic sorbent, which is sawdust from coniferous and/or deciduous trees with a particle size of 5.5 - 45.0 mm, preferably 10.5 mm, with a water content of 5 - 30%, preferably 25% and 5.0 - 10 p.w. preferably 5 p.w. of a mineral stabilizer, which is calcium sulphate with a water content of <10%, preferably <15%.

Description

Organic-mineral fertilizer

The subject of the invention is an organic-mineral fertilizer produced from hygienized sewage sludge, stabilized with cereal straw, sawdust of coniferous and deciduous trees, calcium sulphate and calcium oxide.

Patent 242576 titled "Method for producing organic-mineral fertilizer and organic-mineral fertilizer" discloses that in the first stage, municipal sewage sludge is heated at a temperature from 55°C to 65°C for 20 to 30 minutes, and during heating a pressure of 0.10 MPa is used. In the second stage, diatomite is added to the heated sewage sludge in an amount of 0.25 to 1.5 kg per 1 kg of dry mass of sewage sludge and mixed. In the third stage, the granulate is formed, and in the fourth stage the granulate is dried at a temperature of 60°C to 85°C for 30 to 60 minutes, and then in the fifth stage the granulate is crushed.

There is a known method of producing mineral-organic fertilizers (Patent PL184434B1) in loose form using sewage sludge with a water content of 60% to 90% to which up to 25% of the volume of powdered calcinated calcium, up to 5% of the volume of semi-aqueous gypsum and ashes from electrothermal plants or thermal power plants are added, up to 5% in terms of nitrogen and phosphorus oxide (V) as nitrogen and phosphorus compounds in the form of alkaline compounds and alkaline earth metal - and in an amount of 5% in terms of potassium oxide, potassium compounds.

According to the description of the PL421521A1 patent, the method of producing organic-mineral fertilizers is carried out using sewage sludge from mechanical-biological sewage treatment plants. In the description, sewage sludge with a dry matter content of 25% will be mixed with combustion by-products in a weight ratio of 1:1, based on dry matter. An organic fertilizer is known from the description of the patent PL353419A1, which consists of composted municipal sewage sludge and soil and mineral improvers such as brown coal and mineral wool fibers.

Patent PL209847 discloses a method for producing granulated organic fertilizers from sewage sludge after methane fermentation, in which 2 - 5% of glauconite on a dry basis is introduced into the sludge after methane fermentation, and after mixing, the sludge is dried and granulated to a dry matter content above 92%. According to the description of the invention, the advantage of this solution is that it effectively immobilizes heavy metal ions, thus preventing them from entering groundwater.

The method of obtaining organic fertilizer from stabilized municipal sewage sludge as an invention PL420420A1 based on the fact, that 30% by weight as dolomite powder with a grain size of 0.2 mm, 5% by weight of quicklime and 1% by weight of cellulose fibers are added up to 64% by weight of a mixture made from sewage sludge with a water content of 75%. The whole is transferred to a dynamic counterrotating mixer, then to a disc granulator and then to a dryer, where the product is dried at a temperature from 105°C to 140°C, preferably for 2 hours.

The patent PL209857B1 presents a method of producing fertilizer by mixing 15% to 25% by weight of dry weight of wet sewage sludge hygienized with quicklime with cereal straw. The entire processed mixture is subjected to the granulation process.

The granulated organic-mineral fertilizer and the method of its production are described in the patent PL234562 in that, it contains ground phosphate rock and organic components, constituting organic waste from agricultural and forestry activities, and additionally urea and dried cattle manure, with the ratio of organic components to phosphate rock being up to 3.5:1, the C:N ratio is 20:1-33:1, and the content of dried cattle manure is no more than 0.11% by weight. From the patent description PL169896B1, there is known a method of producing a mineral-organic fertilizer with an increased content of magnesium and potassium from a mixture of post-fermentation sludge with a dry matter content of 18% and partially calcinated dolomite, calcinated basalt rock and cement dust.

From the publication of Ewa Gorska et al. (Protection of the Environment and Natural Resources No. 40, 2009) a fertilizer is obtained by mixing sewage sludge and pine sawdust and then composting the fertilizer thus prepared for microbiological hygienization. Chemical tests have shown that wood sawdust composts can be used as organic fertilizers to improve soil fertility and productivity.

A method of producing organic-mineral fertilizers based on municipal sewage sludge (Patent PL209857) consisting in mixing at least 20% by weight of oat straw with 15 to 25% by weight of dry weight of sludge from wet sewage sludge hygienized with quicklime and processing the mixture into granules. Before mixing, cereal straw is mechanically crushed by cutting and fiberising in an air-dry state, and the crushed straw particles are added to sewage sludge in an amount of 25 to 30% by weight in relation to the weight of the mixture, and then the mixture is forced through a matrix with calibrating holes, next cutting into sections, which are then granulated and aged.

The purpose of the invention is to produce an organic-mineral fertilizer based on sewage sludge, multi-component, with integrated action mechanisms, including fertilization and improvement of soil structure, and increase of soil microbiological activity. The produced organic-mineral fertilizer will improve the vitality of degraded soils. Thanks to the addition of cereal straw, sawdust dust, calcium sulphate and calcium oxide, it is suitable for wide use in agricultural, horticultural and orchard production as well as the regeneration of all heavily degraded materials. Also for the production of plant biomass for energy purposes.

The essence of the invention is an organic-mineral fertilizer stabilized with straw and calcium sulphate based on hygienized sewage sludge, calcium oxide, cereal straw, sawdust from coniferous and deciduous trees and calcium sulphate, which contains 35-70 parts by weight (p.w.) preferably 65 p.w. hygienized sewage sludge with 60- 80% water content, preferably 75%, 5 - 15 p.w. preferably 5 p.w. of calcium oxide as a pH regulator, with water content <10%, preferably <5%, 10 - 25 p.w. preferably 15 p.w. of organic stabilizer, which is cereal straw with a particle size of 5.0 - 35.0 mm, preferably 10 mm, with a water content of 5 - 35%, preferably 30%, 25 - 58 p.w. of lignin- cellulose organic sorbent, which is sawdust from coniferous and/or deciduous trees with a particle size of 5.5 - 45.0 mm, preferably 10.5 mm, with a water content of 5 - 30%, preferably 25% and 5.0 - 10 p.w., preferably 5 p.w. of mineral stabilizer, which is calcium sulphate with a water content of <10%, preferably <15%.

Thanks to the use of the solution according to the invention, the following technical and utility effects were achieved:

• the additional components used do not have a negative impact on the soil and the environment,

• the basic components is hygienized sewage sludge,

• immediate effect in the form of organic-mineral fertilizer obtained within a few to several minutes,

• the organic-mineral fertilizer is fully biodegradable,

• neutralization of over 80% of unpleasant odors originating from sewage sludge,

• reducing the water content in sewage sludge (70-85%) to 30-40% in the finished fertilizer, • obtaining the stability of nutrients in relation to other technologies related to thermal processing,

• there are no unpleasant odors during the processing and when using organic-mineral fertilizer,

• avoiding the use of toxic waste (e.g. containing chemicals or heavy metals),

• organic-mineral fertilizer does not lead to the emission of CO? and other volatile gases such as sulfuric or chloride acid vapors,

• possibility of easy packaging of ready-made organic-mineral fertilizer,

• possibility of use for recultivation of degraded areas and for improving the structure of weak soils,

• positive impact on the environment through energy savings, return of biomass to the environment and, as a result, the possibility of reducing the greenhouse effect,

• the obtained product is cheap and does not require highly specialized technology.

The essence of the invention is to optimize the process of producing organic-mineral fertilizer by mixing hygienized sewage sludge with cereal straw and sawdust from coniferous and deciduous trees, leading to structural stabilization of the fertilizer mixture. The next stage is enriching the fertilizer mixture with calcium sulphate and calcium oxide.

The target effects of the invention are sustainable revitalization and improvement of soil structure, increasing the microbiological activity of the soil. The created organic-mineral fertilizer will improve the vitality of degraded soils. Thanks to the appropriate relationship between the organic and mineral structure and reduced processing costs, it is an appropriate fertilizer product in large-scale agricultural production and revitalization of heavily devastated soils. The invention is illustrated by the following examples:

Example 1

The organic-mineral fertilizer stabilized with cereal straw and calcium sulphate contains 35 parts by weight (p.w.) of hygienized sewage sludge with 60% water content; 10 p.w. of calcium oxide as a pH regulator, with water content <5%; 25 p.w. of an organic stabilizer, which is cereal straw with a particle size of 10.50 mm and a water content of 5%; 25 p.w. of lignin-cellulose organic sorbent, which is sawdust from coniferous and deciduous trees with a particle size of 5.50 mm with a water content of 5% and 5 p.w. of a mineral stabilizer, which is calcium sulphate with water content <10%.

The organic-mineral fertilizer is characterized by the following properties: - dry matter content 55.0%, - specific surface area of the organic-mineral fertilizer 70.0 m²/g dry matter; - pH of the mixture equal to 6.0; - N content 1.5%; P 1.0%; Ca 9857.7 mg/kg; Mg 1077.2 mg/kg; K 2384.7 mg/kg; Zn 95.5 mg/kg; Mn 101.0 mg/kg; Fe 342.0 mg/kg.

Example 2

The organic-mineral fertilizer stabilized with cereal straw and calcium sulphate contains 55 parts by weight (p.w.) of hygienized sewage sludge with 80% water content; 15 p.w. of calcium oxide as a pH regulator, with water content <3%; 15 p.w. of an organic stabilizer, which is cereal straw with a particle size of 5.50 mm and a water content of 20%; 10 p.w. of lignin-cellulose organic sorbent, which is sawdust from coniferous trees with a particle size of 10.50 mm with a water content of 20% and 15 p.w. of mineral stabilizer, which is calcium sulfate with water content <15%.

The organic-mineral fertilizer is characterized by the following properties: - dry matter content 45.0%, - specific surface area of the organic-mineral fertilizer 60.0 m²/g dry matter; - pH of the mixture equal to 7.5; - N content 2.0%; P 1.5%; Ca 8658.7 mg/kg; Mg 2186.2 mg/kg; K 2863.7 mg/kg; Zn 108.8 mg/kg; Mn 115.0 mg/kg; Fe 355.0 mg/kg.

Example 3

The organic-mineral fertilizer stabilized with cereal straw and calcium sulphate contains 65 parts by weight (p.w.) of hygienized sewage sludge with 75% water content; 5 p.w. of calcium oxide as a pH regulator, with water content <15%; 10 p.w. of an organic stabilizer, which is cereal straw with a particle size of 35 mm and a water content of 25%; 10 p.w. of lignin-cellulose organic sorbent, which is sawdust from deciduous trees with a particle size of 30.5 mm with a water content of 5% and 10 p.w. of a mineral stabilizer, which is calcium sulfate with water content <10%.

The organic-mineral fertilizer is characterized by the following properties: - dry matter content 45.0%, - specific surface area of the organic-mineral fertilizer 55.0 m²/g dry matter; - pH of the mixture equal to 7.0; - N content 3.5%; P 2.50%; Ca 10173.7 mg/kg; Mg 1809.2 mg/kg; K 3518.7 mg/kg; Zn 112.8 mg/kg; Mn 138.3 mg/kg; Fe 495.2 mg/kg. Example 4

The organic-mineral fertilizer stabilized with cereal straw and calcium sulphate contains 70 parts by weight (p.w.) of hygienized sewage sludge with 85% water content; 5 p.w. of calcium oxide as a pH regulator, with water content <5%; 15 p.w. of an organic stabilizer, which is cereal straw with a particle size of 30 mm and a water content of 35%; 5 p.w. of lignin-cellulose organic sorbent, which is sawdust from coniferous and deciduous trees with a particle size of 45.0 mm with a water content of 30% and 5 p.w. of a mineral stabilizer, which is calcium sulfate with water content <15%.

The organic-mineral fertilizer is characterized by the following properties: - dry matter content 40.0%, - specific surface area of the organic-mineral fertilizer 40.0 m²/g dry matter; - pH of the mixture equal to 7.5; - N content 4.0%; P 3.0%; Ca 13008.1 mg/kg; Mg 2508.2 mg/kg; K 43845.8 mg/kg; Zn 130.0 mg/kg; Mn 206.1 mg/kg; Fe 501.8 mg/kg.

Claims

Claim

The organic-mineral fertilizer stabilized with cereal straw and calcium sulphate based on hygienized sewage sludge, calcium oxide, cereal straw, sawdust from coniferous and deciduous trees and calcium sulphate, characterized by the fact that it contains 35-70 parts by weight (p.w.) preferably 65 p.w. of hygienized sewage sludge with 60-80% water content, preferably 75%, 5 - 15 p.w. preferably 5 p.w. of calcium oxide as a pH regulator, with water content <10%, preferably <5%, 10 - 25 p.w. preferably 15 p.w. of organic stabilizer, which is cereal straw with a particle size of 5.0 - 35.0 mm, preferably 10 mm, with a water content of 5 - 35%, preferably 30%, 25 - 58 p.w. of lignin-cellulose organic sorbent, which is sawdust from coniferous and/or deciduous trees with a particle size of 5.5 - 45.0 mm, preferably 10.5 mm, with a water content of 5 - 30%, preferably 25% and 5.0 - 10 p.w. preferably 5 p.w. of mineral stabilizer, which is calcium sulphate with a water content of <10%, preferably <15%.