Українська  Русский
DonNTU   Masters' portal

Abstract

Content

Introduction

Until recently, the sewage sludge was taken to landfills, stored in sludge collectors, which occupy huge areas, in a hot climate, dried in the sun, dumped in the ocean. In recent years, methods have been developed for the beneficial use of dehydrated sediments and ash from their combustion.

In Europe and the countries of the Baltic Sea region, there are various strategies for recycling sediment. In countries such as the Netherlands, Belgium and Switzerland, the agricultural use of sewage sludge is prohibited or restricted, so the sediment is burned. In other countries (for example, in Finland, Estonia and Norway) composted sediment is used for the improvement of green areas. In some countries, for example, in Iceland, Malta and Greece, the whole sediment is exported to the landfills. In Russia and Belarus, collection of sediment in sludge accumulators is common.

1.Urgency of work

The urgency of my work is that due to the utilization of sewage sludge, a number of important problems are being solved. First of all, this: reducing the load on the lithosphere, as a consequence - the conservation of fertile soils, clean ground and surface water, as well as the utilization of WWS by vermicomposting will make it possible to obtain an environmentally friendly organic fertilizer - biohumus.

2. Purpose, objectives, object, subject of research, scientific novelty

The aim of the work is to study the possibility of using the municipal sewage sludge received from the treatment facilities of the company "Water Donbassa" for the production of biohumus and cultivation of useful plants.

asks:

a) Describe the treatment of SALT in Donetsk;

b) Determine the advantages and disadvantages of using SALT as a fertilizer;

c) Describe the technology of vermicomposting;

d) Establish compliance of the biohumus with regulatory requirements;

e) Present the methodology of the experiment;

e) On the basis of the results obtained, it is concluded that the biohumus obtained from SALT influences the vital activity of plants.

The object of the study is the sedimentation of municipal wastewater from treatment facilities of the KP "Company" Water of Donbass ".

The subject of the study is the physicochemical, microbiological, sanitary and epidemiological characteristics of the SALT.

Scientific novelty. For the first time, based on the results of complex studies, a comprehensive ecological assessment of urban wastewater sediments is given by their composition and properties. On the basis of experimental studies, the possibility of environmentally safe use of WWS in agricultural production is justified. The ecological basis of soil utilization of WWS has been theoretically determined and practically confirmed.

3 General characteristics of urban sewage sludge

On the territory of the Donetsk region, in particular, a huge amount of industrial and domestic wastes, including precipitation, released during the purification of domestic sewage (WWS), the number of the last stored on sludge sites and in sludge ponds of sewage treatment plants of cities and settlements exceeds 2 million t and continues to increase daily.

The bulk of the WWS is stored on silt areas and dumps, landfills, creating technological problems in the process of wastewater treatment. The conditions of their storage, as a rule, lead to contamination of surface and groundwater, soils, vegetation. SALW stored on mud maps and heaps belong to the second class (highly hazardous) or third class (moderately hazardous) wastes. The released harmful gases have an unpleasant odor and can exceed the permissible concentrations several times. Their smell is 4-5 points on the scale of organoleptic indicators.

4 Experiment Procedure

On the basis of the State Institution "Donetsk Botanical Garden", a study was made of the effect of biohumus produced from excess activated sludge obtained from WWTP Donbass water treatment facilities. Parameters such as germination energy (EPS) and seed germination (Vsx) were estimated.

In the course of the experiment, 4 types of substrate were prepared with different contents of the studied vermicompost (10%, 25%, 50%, 100%) and a control earth mix that did not contain biohumus. As the object were chosen oats and white mustard. For each variant of the experiment, 50 pieces were sown. seeds in 5-fold repetition. In total, 750 seeds of each plant species participated in the experiment.

The experiment was carried out as follows:

A soil mixture was prepared in which biohumus was added in certain concentrations (10%, 25%, 50%, 100%) and a control earth mix containing no biohumus without any other fertilizers.

As the object of the study were selected Oats inoculum and Mustard white, because in the conditions of our region, these plant species have high seed germination.

12.01.2016 in the pots with soil were seeded seeds of these plants for 50 pcs. seeds in 5-fold repetition.

The sprouting of these plant species occurred under certain conditions: medium air = 22 ° C, medium temperature = 24 ° C, with periodic irrigation (once every 3 days) with ordinary standing water.

25-26.01.2016. Extraction of plant seedlings (carefully extract a bunch of seedlings together with a clod of soil from the pot, soak it in water at room temperature for 40 minutes to separate sprouts from the soil mixture and separate the selig bundle itself) and root washing (from the remaining soil mixture ordinary water at room temperature).

Adduction of sprouts to the air-dry state at t = 105 ° C.

Weighing seedlings on analytical scales.

Determination of the field moisture capacity of the soil mixture:

     - Select 20 g of each soil in crucibles;

     - put in the drying cabinet;

     - we bring it to an air-dry state at t = 105 ° C for 3 hours;

     - grind the resulting mass in a mortar and sift through a sieve (d = 0.25 mm)

- We sift the sown soil mixture into a cup with a thin layer and drip onto it with water until the first separated drop of water (full moisture capacity);

   Conclusion

Thus, when growing 100% vermicompost, the indices were much lower than in the control sample. In the variant with pure vermicompost, water was poorly bound to the substrate, and therefore the question arose concerning the negative effect on the field moisture capacity of the soil mixture formed. The analysis carried out to determine the field moisture capacity of substrates showed that when biohumus is added to the soil up to 50% there is no noticeable change in the field moisture capacity.

It is noted that the work is not finished yet, materials will be supplemented by studies on the content of heavy metals. The final version of the work can be obtained from the author or his supervisor after June 2018.

References 

1. Goldfarb, L.L. Experience in the recycling of municipal sewage sludge as fertilizer. - M.: - 1983. - 60 sec.

2. Pakhnenko, E.P. Sewage sludge and other non-traditional organic fertilizers [Electronic resource] .- 3rd ed. Moscow: BINOM. Laboratory of Knowledge 2015. - 7 pp.

3. Melnik, I.A. Vermiculture and its effectiveness. - К .: UkrNIINTI, 1990.- 32с.

4. Aristarkhov A.N. Optimization of plant nutrition and application of fertilizers in agroecosystems. - M.: CINAO, 2000. - 524p.

5. Belyaeva SD, Gunter L.I. and others. Organization of work on the use of sewage sludge as fertilizer. 2002.-56s.

6. SanPiN 2.1.7.573-96 "Hygienic requirements for the use of wastewater and their precipitation for irrigation and fertilization".

7. Methodological guidelines for the determination of heavy metals in soils and agricultural lands and crop production (2nd ed., Rev. and add.) .- Moscow: TsINAO, 1992.- 61 p.

8. GOST 17.4.2.01-81. Interstate standard. Protection of Nature. Soil. Nomenclature of indicators of the sanitary state 1981.-M: Standardinform, -32 p.

9. Alekseev, Yu.V. Heavy metals in soils and plants. P .: Agropromizdat, 1987.-144s.

10. DSTU 7369: 2013 Sewage. Requirements for wastewater and their deposits for irrigation and fertilization. Kiev, 2014.- p.2-5.