RU2498969C2 - Non-traditional organic fertiliser - Google Patents

Abstract

FIELD: agriculture.

SUBSTANCE: non-traditional organic fertiliser based on sewage sludge and conifer-hardwood sawdust. As a sorbent after the thermophilic stage it comprises additives of organic wastes in the form of waste of mushroom substrate or horticultural wastes taken in an amount of 10-12.5% by weight of dry matter.

EFFECT: invention enables to improve the agro-chemical properties of the fertiliser.

2 tbl, 2 ex

Description

The invention relates to the field of forestry, agriculture and ecology and can be used in carrying out measures to improve agrochemical properties as an unconventional organic fertilizer.

It is known to use sewage sludge for their disposal and to create non-traditional types of fertilizers based on them [1]. However, this raises the problem of a high hazard class due to the content of heavy metals (HM) in concentrations exceeding the maximum permissible concentrations (MPC), and, as a result, the limited use of such fertilizers in agriculture. Heavy metals are practically not biodegradable, therefore, when composting organic waste, these metals accumulate in composts. Mobile forms of TM, disrupting the regulation of cellular mechanisms, accumulate in plants in quantities that affect the growth and development of agricultural crops [2].

The disadvantages of non-traditional organic fertilizers are that humic substances, having a high absorption capacity, reduce the mobility in the soil of some metals (aluminum, cobalt, lead), but in some cases complete fixation of heavy metals does not occur [3, 4].

An unconventional organic fertilizer based on sewage sludge with the addition of coniferous-deciduous sawdust was taken as a prototype [9].

The technical result is achieved by the fact that non-traditional organic fertilizer based on sewage sludge with the addition of softwood sawdust as an sorbent contains additives from organic waste, for example spent mushroom substrate, or fruit and vegetable waste introduced after the thermophilic stage.

When compiling a mixture of sewage sludge and softwood sawdust, the share of each is determined by the formula M _I = (W _II -W _opt. ) / (W _opt. -W _I ), where M _I is the mass of softwood sawdust per 1 ton sewage sludge, t; W _I - moisture coniferous deciduous sawdust,%; W _opt. - optimal humidity of the composted mixture,%; W _II - humidity of sewage sludge,%, or according to the formula M _II = (S _I -S _opt. ) / (S _opt. -S _II ), where M _II - mass of sewage sludge 1 ton of coniferous-deciduous sawdust; S _I - the ratio C: N in softwood sawdust; S _II - C: N ratio in sewage sludge; S _opt. - the optimal ratio C: N in the compost mixture [9]. The novelty lies in the fact that after passing the thermophilic stage of composting a mixture of sewage sludge with softwood sawdust, additives from organic waste, for example, spent mushroom substrate or fruit and vegetable waste, are introduced as a sorbent. The dry matter mass of the additive should be 10-12.5% of the dry matter mass of the mixture from sewage sludge and softwood sawdust.

Additives from organic waste, the components of which have sorption properties, have an acidity close to a neutral environment and readily available organic matter:

- fruit and vegetable waste contains in its composition: cellulose, pectin, starch;

- spent mushroom substrate contains in its composition: chitin, cellulose.

Example 1

Organic waste was added to the mixture of sewage sludge and softwood sawdust (component ratio 1: 3 by weight of dry matter), which passed the thermophilic stage of composting: a) waste mushroom substrate; b) fruit and vegetable waste. The dose of additives was 2.5; 5; 7.5; 10; 12.5; fifteen; 25.0% by weight of dry matter of a mixture of sewage sludge and softwood sawdust.

After thorough mixing, the compositions were placed in plastic bags. The bags were placed in an upright position in wooden crates in the open air at the Training and Experimental Leskhoz MarSTU. Duration of exposure is 6 months. During the experiments, a constant humidity of at least 70% was maintained. The experiment was laid in 3 replicates. After six months exposure, the obtained composts were subjected to chemical analysis (Table 1) in order to evaluate the effectiveness of sorbents and biotesting to determine the possible reduction in the toxicity of compost based on WWS after adding organic additives (Table 2).

Table 1 The content of mobile forms of heavy metals in non-traditional organic fertilizer using organic additives The concentration of additives,% Spent mushroom substrate Fruit and vegetable waste Pb Cu Zn Cd Ni Pd Cu Zn Cd Ni 2,5 7.16 16,99 37.89 1,62 8.57 7.16 15.79 34.58 1,60 7.89 5 7.16 16.90 36,99 1,62 8.01 7.06 14.00 34.46 1.55 7.59 7.5 7.11 16.86 34.88 1,62 7.69 7.06 12.78 33.90 1.55 6.99 10 7.11 16.75 33.71 , 62 7.18 7.00 10.19 33.65 1.47 6.55 12.5 6.76 16.33 33.98 , 60 7.14 4.74 6.75 29.15 1.15 6.80 fifteen 6.43 5.91 27.89 1.43 4.49 4.30 6.35 28.14 1.15 6.30 without additives 7.17 16,99 38.49 1,62 8.78 7.17 16,99 38.49 1,62 8.78 Hcp ₀₅ 0,038 0,055 0.106 0,041 0,052 0,091 0.113 0,025 0,038 0,033

The results of atomic spectrometric analysis showed a significant decrease in the content of mobile forms of heavy metals in compost when introducing spent mushroom substrate in comparison with the control. The optimal dose of this additive in non-traditional organic fertilizer is 12.5% by weight of dry matter of a mixture of sewage sludge and softwood sawdust. When fruit and vegetable waste is added as an additive, the mobility of heavy metals is also reduced in comparison with the control. The optimal dose varies from 10 to 12.5%. When an additive is added at a given concentration, mainly mobile forms of heavy metals are reduced, not gross, which tells about the sorption properties of the added additives, and not a dilution of the concentration of heavy metals in an unconventional fertilizer based on sewage sludge. After adding additives, the concentration of Pb, Cu, Ni Cd, Zn in non-traditional fertilizer decreases.

Example 2

The results of the biotesting of Table 2 indicate a decrease in the hazard class in option 2 - an additive of the fungal substrate was used: all test organisms showed the fifth hazard class, i.e. virtually no toxicity. In option 3, the additive “fruit and vegetable waste” was used, only algae showed toxicity, tests on daphnia and bacteria indicated a fifth hazard class. When testing LEU without additives, all test organisms indicated a fourth hazard class.

It is obvious that the introduction of organic waste, which has good sorbing properties, as additives in the creation of unconventional ameliorants can reduce the toxicity of LEU.

After adding additives, the agrochemical properties of non-traditional fertilizers are also improved: the content of organic matter in compost increases by 10-15%, the content of nitrogen and potassium increases by about 2 times, and the phosphorus content increases.

Thus, the use of organic waste as additives to reduce the degree of pollution and toxicity of non-traditional fertilizers is environmentally friendly, favorably affects the agrochemical properties of the fertilizer and reduces the mobility of heavy metals in compost. The use of organic waste as additives to reduce the toxicity of non-traditional fertilizers is very simple in practical implementation, does not require significant labor and material costs.

Bibliography

1. Shibaev, M.E. Regulation of the content of heavy metals in plants using inoculated composts / M.E. Shibaeva I.A. Arkhipchenko // Ecology and Industry of Russia. - 2006. - No. 8. S.33-35.

2. Heavy metals in soils and plants and their analytical control / E.A. Alexandrova, N.G. Gaidukova, N.A. Koshelenko, Z.N. Tkachenko-Krasnodar: KGAU, 2001 .-- P.6-11.

3. Gaidukova, N.T. About the influence of humus and iron on the state of heavy metals in leached chernozem of the Western Ciscaucasia / N.G. Gaidukova, I.A. Lebedovsky // Science of the Kuban. - 2005. - No. 3. S.34-37.

4. Mechanisms of sorption of metal ions by fungal chitin-containing complexes "/ LF Gorovoi, AP Petyushenko // New prospects in the use of chitin and chitosan: Materials of the Fifth Conference, Moscow - Schelkovo. - M.: VNIRO Publishing House, 1999 - S.134-136.

5. Romanov, E.M. Growing seedlings of woody plants / E.M. Romanov, Yoshkar-Ola, 2000 .-- S.212-439.

6. PND F T 14.1: 2: 4.12-06 (PND F T 16.1: 2: 3: 3.9-06) The methodology for determining the toxicity of water extracts from soils, sewage sludge and waste, drinking, waste and natural water by mortality test Daphnia magna Straus. Krasnoyarsk State University

7. PND F T 14.1: 2: 3: 4.11-04 (PND F T 16.1: 2.3: 3.8-04) Methodology for determining the toxicity of water and water extracts from soils, sewage sludge and waste by changing the intensity of bacterial bioluminescence test system " Ekolyum "on the Biotox-10 device. LLC Scientific Center "Ecological Perspective"

8. PND F T 14.1: 2: 3: 4.10-04 (PND F T 16.1: 2.3: 3.7-04) Methodology for determining the toxicity of surface fresh, ground, drinking, wastewater samples, water extracts from soils, sewage sludge and waste by changing the optical density of the culture of Chlorella algae (Chlorella vulgaris Beijer). Krasnoyarsk State University

9. Mukhortov, D.I. Optimization of technological parameters of the production of non-traditional organic fertilizers in forest nurseries / D.I. Mukhortov, E.M. Romanov, A.A. Mamaev / Forestry, No. 3, 2011. - P.21-23.

Claims (1)

Non-traditional organic fertilizer based on sewage sludge and softwood sawdust, characterized in that as a sorbent after the thermophilic stage it contains additives from organic waste in the form of spent mushroom substrate or fruit and vegetable waste, taken in an amount of 10-12.5% by weight of dry substances.