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THE USE OF DOMESTIC WASTEWATER FOR AGRICULTURAL
IRRIGATION Tursunova E.A. Email: [email protected]
Tursunova Elza Akramovna - Candidate of economic sciences, Associate Professor, DEPARTMENT OF DESIGNING, CONSTRUCTION AND EXPLOITATION OF ENGINEERING COMMUNICATIONS, TASHKENT INSTITUTE OF ARCHITECTURE AND ENGINEERING, TASHKENT, REPUBLIC OF UZBEKISTAN
Abstract: in article is being conducted the analysis of international practice the use of domestic wastewater for irrigation of agriculture fields and municipal green spaces. Also here are given the distinctive features of use the biological and mechanical treated domestic wastewater. The preferred methods for the treatment of domestic wastewater of small settlement and big cities are considered. The methodology of entering wastewater to the root zone of the plants is presented in this article, which provides not only watering, but nutrition for plants too, at the same time maintaining the purity of groundwater, also topsoil and that's surface.
Keywords: domestic wastewater, irrigation, agriculture, treatment facilities, mechanical and biological treatment.
ИСПОЛЬЗОВАНИЕ БЫТОВЫХ СТОЧНЫХ ВОД ДЛЯ ОРОШЕНИЯ В СЕЛЬСКОМ ХОЗЯЙСТВЕ Турсунова Э.А.
Турсунова Эльза Акрамовна - кандидат экономических наук, доцент, кафедра проектирования, строительства и эксплуатации инженерных коммуникаций, Ташкентский архитектурно-строительный институт, г. Ташкент, Республика Узбекистан
Аннотация: в статье проведен анализ мировой практики использования бытовых сточных вод для орошения сельскохозяйственных земель и городских зеленых насаждений. Приведены отличительные черты использования биологически и механически очищенных хозяйственно-бытовых стоков. Рассмотрены предпочтительные методы очистки бытовых стоков небольших поселков и крупных городов. Представлена методика внесения сточных вод в прикорневую зону растений, обеспечивающая не только полив, но и питание растениям, в то же время сохраняющая чистоту грунтовых вод, а также верхних слоев почвы и ее поверхности.
Ключевые слова: бытовые сточные воды, орошение, сельское хозяйство, очистные сооружения, механическая и биологическая очистка.
УДК 632.153:636.086.15
Nowaday, enough widely distributed the use of the domestic wastewater in farming and agriculture, especially in countries with arid climate. Moreover, it allows to save water resources, mineral and organic fertilizers, also to increase food production. Primarily, wastewater uses for irrigation of agriculture crops, for watering green spaces and in pond sections.
The watering of green spaces with treated wastewater is widely distributed in USA, Israel, Latin America, Australia, Mediterranean and Arab countries, North Africa and in India. Also, for irrigation of parks, street lawn, golf courses, roadside green lanes is used the wastewater. The treated watering is implemented as well as inside the soil, through the connectivity of the underground irrigation system and superficially - with tank vehicles, watering car.
The distinguishing feature of the irrigation system inside the soil with treated domestic wastewater was using as well as biological treated urban wastewater, and mechanical treated domestic wastewater of small town type villages and livestock complexes [1].
Recent years, abroad is increasingly implemented the method of entering the wastewater inside the soil for irrigation of agricultural fields, in which completely observances sanitary and hygienic and agro-technical requirements and they use their fertilisation properties in the best way as well as by soil, and by agricultural plants.
The practice of using mechanical treated domestic wastewater for irrigation on agricultural fields has shown, that there is not found out noticeable accumulation of mobile chemical compounds, organic substances, pathogenic microorganisms, helminth eggs in the soil. Sewage organic compounds and complex chemical compounds are transformed by macro- and microorganisms of soil and agricultural plants to more simple forms, after falling into the soil, which are then being absorbed by soil and cultivated production. Domestic and foreign experience has shown, that the watering with such wastewater (according to nutritional necessities of grown crops) or nothing requires for supplementary entering of mineral fertilizers or their consumption is minimal.
Entering the wastewater directly to the root inhabited soil layer the most comprehensively meets the sanitary and hygienic requirements. The treated wastewater is delivered by wetters to the depth of soil up to 60 centimeters from the the surface and does not affects the environment. At the same time on the upper layers of the soil and on that's surface pollution does not occurs. The development cycle of helminth is disrupted after getting them into the soil and they die. Furthermore, the helminth eggs are destroyed by mites, seaweeds, fungus and other microorganisms. The pathogenic microorganisms also, die quickly enough in the soil conditions.
With correct regime of irrigation the depth of drench with wastewater does not exceed 1,5 metres, also possibility contamination with pathogens of groundwater is excluded, if that is located in a great depth.
The Domestic wastewater of individual residential buildings and small towns, which is not composed of industrial wastewater, generally does not contains toxic substances in dangerous concentrations for the soil and for plants. The wastewater is rich with nutrients and possesses with high fertilize value.
For the secondary use of such wastewater for the irrigation of plants, there is not necessity for that's fully biological treatment in aeration constructions, enough only preliminary mechanical treatment (Gravitational upholding), which protects the watering system from clogging with rough impurities. Moreover, completely biological treatment is leading to a decrease fertilize value of wastewater: 26% - for nitrogen, 18% - for potassium, 10% - for calcium and phosphorus. Partially get lost boron, manganese, zinc, molybdenum and other microelements, which is necessary for plants. Almost completely gets lost the biological part of the wastewater (organic substance - by 72,4%, useful microorganisms - by 94,0%).
Such a method of wastewater treatment turned out to be more cost-effective, in comparison with artificial biological treatment in major treatment complexes. The method was recommended to the widespread implementation in the agricultural production practice, because provides a positive impact on the chemical composition, agglomeration properties of irrigated soils, productivity of agriculture crops, provides with higher quality treatment of wastewater, at comparatively low capital expenditure to construction of treatment facilities. ( inside the soil system irrigation) and that's exploitation in comparison with artificial aeration treatment facilities.
It is noteworthy, that on the municipal wastewater the content of the benzopyrene carcinogen is from 12,8 * 10 - 12 to 567,6 * 10 - 12 mg/l, what is much lower from the maximum permissible concentration (5* 10 - 6 mg/l) of the household and drinking water. Consequently, it is necessary to conduct the additional treatment of the municipal wastewater that is used for the irrigation purposes, with application of the wastewater
preparation technologies in storage ponds. The preparation of wastewater on the maps is maintained with flow and contact methods. In the flow ponds the wastewater sequentially flows from one pond to another (the number of steps is five). Meanwhile, the purity level of the water is gradually increased and occurs the oxidation of organic substances and that's completely deworming, owing to sedimentation of helminth eggs in the bottom sediments. In ponds the wastewater is being around for 2-3 months and then flows to the irrigation.
Therefore, the municipal wastewater after preliminary preparation can also be used for the irrigation of agriculture crops.
References / Список литературы
1. Vaycel A.A. Mekhanicheskie metody ochistki stochnyh vod [Mechanical methods of wastewater treatment] // Nauka, obrazovanie i kul'tura [Science, education and culture], 2019. № 3 (37). С. 13-14 .
2. Alyoshina N.I., Makarichev S.V. Ispol'zovanie gorodskih stochnyh vod dlya orosheniya mnogoletnih trav [The use of municipal wastewater for perennial grasses irrigation] // Vestnik Altajskogo gosudarstvennogo agrarnogo universiteta [Altai State University of Agriculture], 2007. № 10 (36). С. 23-28.
