SK4698A3 - Process for the preparation of earth for cultivating flowering plants - Google Patents

Abstract

Preparation of potting compost comprising class I and II sludge with a moisture content of 0-85 (especially 60-85) % and a dry weight of 15-100 (especially 15-40) % comprises heating a mixture of matrixed or layered silicates as earth based minerals and peat as an acidic carbonate based carrier to 80-90 degrees C, together with a chemical disinfectant.

Description

METHOD OF MANUFACTURING SOIL FOR FLOWERS

Technical field

The subject of the invention is a method of making soil for flowers.

BACKGROUND OF THE INVENTION

Flower or horticultural soil is a cultivation substrate which must contain the nutrients necessary for plant growth.

Ready-to-use flower land is a desirable product in horticulture, agriculture and households and is often obtained by composting green waste.

Another form of organic waste disposal is the treatment of waste water in wastewater treatment plants, where a significant amount of sewage sludge is generated. Sewage sludge is classified according to its composition into quality classes, which classification is usually carried out according to the content of harmful substances, especially according to the content of unwanted heavy metals. Sewage sludge of grades I and II has a heavy metal content below the amount harmful to horticultural businesses. This sewage sludge, on the other hand, is possibly contaminated with germs and / or bacteria, so caution must be exercised in its treatment.

Various processes are known from the literature for the treatment of sewage sludge or for the production of soil improvers.

Thus, WO 85/04166 discloses a process for producing a soil improver according to which the stabilized, partially dewatered sludge is mixed with a porous mineral, predominantly granular carrier material. A sieved resin slate slag with a grain size of from 0 to 8 mm is preferably used as such a material. This procedure provides a storable and free-flowing soil improver whose production, unlike the agricultural recovery of liquid sludge, allows year-round use of sewage sludge without losing fertilizer and humus substances contained therein.

861 / B

DE OS 32 297 describes a process for treating sewage sludge with the addition of peat.

According to DE 22 43 805 a soil-yielding agent is obtained by mixing the sludge with sand and possibly also with peat.

AT 398 196 B describes a process for producing a mixed flower substrate according to which a ceramic-type base material is mixed with a sewage sludge and a fiber sludge from the pulp and paper industry.

DE 964 603 C relates to a process for the production of slow-acting nitrogen fertilizers in which urea, aldehyde and a natural plant-producing humus, such as peat, are properly mixed. The mixture is heated until a free-flowing product is formed.

According to CH 185 428 A, for the production of fertilizer consisting of sewage sludge and peat, the mixture of sludge and peat is stacked into piles and awaiting an increase in the temperature induced by the organic fermentation processes inside the piles. The multi-layer coating also entails the external fractions in the desired fermentation process. According to the additional patent CH 208 881, stone meal is added to the fertilizer thus prepared.

FR 1 187 241 A describes a process for producing fertilizers in which peat is treated with dissolved silica.

A substrate for growing flowers based on zeolite, vermiculite and peat is known from U.S. Pat. No. 4,337,076.

According to EP 0 153 282, a mixture of sewage sludge, peat as a carbonaceous carrier and polyelectrolyte is used for the production of compost.

SUMMARY OF THE INVENTION

The process according to the invention consists in that for the production of soil for flowers, sewage sludge of quality class I and II with a moisture content of 0 to 85% by weight, preferably 60 to 85% by weight. (dry matter 15-100 wt.%, preferably 15-40 wt.%), heated to 80-90 ° C, mixed with clay materials, preferably tectosilicates.

861 / B and / or layered silicates as a mineral component and with peat as an acidic carbon carrier, and treated with a chemical disinfectant.

Preferably, a disinfectant is used which is combined with the organic substance without residue to form a neutral substance. Disinfectants useful in the food industry are particularly suitable for this purpose.

In particular, formaldehyde or dimethyl dicarbonate are used as disinfectants. Formmaladehyd is converted to formic acid in the presence of oxygen and organic matter, while dimethyl carbonate is decomposed into carbon dioxide and water.

The preferred disinfectant used, which is converted into neutral substances, can be used without any objection to the soils produced for industrial and private purposes.

The addition of minerals and peat may vary in quantity depending on the purpose of the soil so produced for the flowers.

In this way, the sewage sludge produced in wastewater treatment plants, the removal of which is often problematic, has been efficiently recovered and the desired product can be produced from it.

Claims (3)

Process for the production of soil for flowers, characterized in that sewage sludge of quality class I and II with a moisture content of 0 to 85% by weight, preferably 60 to 85% by weight, i.e. a dry matter content of 15 to 100% by weight, preferably 15 It is heated to a temperature of 80 to 90 ° C, admixed with clay materials, preferably tectosilicates and / or layered silicates as a mineral component and peat as an acidic carbon carrier, and treated with a chemical disinfectant. Method according to claim 1, characterized in that a disinfectant is used which is completely converted into a neutral substance with the organic substance. Method according to claim 1 or 2, characterized in that the disinfectant is formaldehyde or dimethyldicarbonate, or another agent useful in the food industry.