DETERMINATION OF THE EFFECTIVENESS OF PURIFICATION OF HOUSEHOLD WASTEWATER AND RECOVERY OF GRAY WATER

АННОТАЦИЯ

 В статье анализируются вопросы оптимизации систем внутреннего водоснабжения и канализации в новых многоэтажных жилых домах. В исследовании были изучены возможности эффективного использования водных ресурсов путем переработки серой воды, поступающей из кухонь и ванных комнат. В целях экономии чистой питьевой воды и снижения воздействия на окружающую среду предлагается использовать центрифужную технологию типа трикантер. С помощью этой технологии эффективно отделяются жиры и органические загрязнители из серой воды. Очищенную воду можно повторно использовать в качестве технической воды для смыва в туалетах. По результатам эксперимента содержание жира снизилось на 95%, БПК - на 83,3%, твердых частиц - на 90%. Научно обоснована возможность экономии 42,8% питьевой воды в каждом домохозяйстве. Этот метод считается социально и экологически полезным.

ABSTRACT

The article analyzes issues of optimizing internal water supply and sewerage systems in new multi-story residential buildings. The study examined the possibilities of efficient use of water resources by processing grey water coming from kitchens and bathhouses. In order to save clean drinking water and reduce the impact on the environment, it is proposed to use centrifuge technology of the trikanter type. With the help of this technology, fats and organic pollutants from gray water are effectively separated. Purified water can be reused as technical water for toilet cleaning. According to the results of the experiment, the fat content decreased by 95%, BPK by 83.3%, and solid particles by 90%. The possibility of saving 42.8% of drinking water in each household is scientifically substantiated. This method is considered socially and environmentally beneficial.

Keywords: wastewater, gray water, tricanter centrifuge, saving, modular cleaning, oil.

Ключевые слова: сточные воды, серая вода, трикантерная центрифуга, экономия, модульная очистка, жиры.

Introduction. Due to population growth and urbanization, the demand for drinking water and sewage systems is increasing. It is especially important to make water supply and sewerage systems in multi-story buildings efficient and environmentally safe. Existing projects do not sufficiently consider the possibility of processing grey water - that is, wastewater from the kitchen and bathhouse. Kitchen oils cause clogs in the pipes, reducing the system's efficiency. In countries such as Germany, Japan, and Korea, membrane technologies, bioreactors, and mechanical methods are used for gray water purification. In Uzbekistan, research in this area is insufficient, the main focus is on the general sewerage system[1-4, 7, 9]. Sokolov (2018) proposed methods for pipeline projects, but the separate collection and processing of grey water is not sufficiently covered. Kholmatov et al. (2020) analyzed water-saving technologies, but their application in residential buildings is not sufficiently demonstrated. Yeriksson (2017) provides processing methods, but does not cover issues related to fats. Huber (2019) assessed the trikanter centrifuge at the industrial level, but its application in the housing system has not been sufficiently studied [1-4]. There is work on purification, water saving, and sewerage calculations, but a comprehensive approach to the separation and processing of grey water and oils is rare. Using the example of newly constructed multi-story buildings, a model for treating gray water with a tricanth centrifuge was proposed.

Research methods and objects. The article examined the possibilities of increasing the efficiency of internal water supply and sewerage systems in new multi-story residential buildings located in the city of Tashkent, in particular, their use for technical purposes (for example, for toilets) through the processing of grey water from kitchens and bathhouses. The object of the research is the internal engineering communications of multi-story residential buildings under construction within the framework of the project of newly constructed buildings, that is, water supply and sewerage networks. Technology for separate collection of gray streams of water from buildings (kitchen, bathroom, washing area), separation of fats and other organic substances using a tricanth centrifuge, and reuse of membrane filter and biologically treated water for technical needs.

The following methodological approaches were used in the study:

Analytical analysis - current regulatory documents (SHNK 2.04.01-2022 and SHNK 2.04.02-2022), international articles and previous studies were studied [5];

Design calculation - the diameter, pressure, and flow velocity of internal water supply and sewerage pipes were calculated;

Experimental method - physicochemical analysis of gray water samples was carried out under laboratory conditions (oil content, BPK, solid particles);

The creation of models of water supply and sewerage systems and a diagram of their functioning were implemented [7];

Figure 1. Gray water use scheme

Comparative analysis - existing traditional systems and proposed innovative solutions were compared in terms of technical, economic, and environmental effectiveness. Data collection and analysis processes. Data were collected from the following sources: Technical documentation and drawings for construction projects; Evidence on existing internal engineering networks in new residential buildings in the city of Tashkent; Results of laboratory analysis based on samples taken from kitchen and bathroom wastewater; Economic indicators of operating costs and water consumption.

The following equipment and software were used in the study:

Trikanter centrifuge - for separating grease and suspensions from grey water;

Laboratory analytical instruments - for determining the pH, BPK, fat, and particle content;

Research conducted on the basis of this methodological approach served to identify modern and resource-saving solutions for internal water and sewerage systems, and to create a scientific basis for their practical implementation. [8].

Research results and discussion. During the study, the following important results were achieved on the effective use of internal water supply and sewerage systems in new multi-story residential buildings in the city of Tashkent, in particular, the use of gray water for technical needs through its processing.

Table 1.

Gray water composition and purification indicators

Physicochemical analysis of gray water samples taken from the kitchen and bathroom yielded the following results: As can be seen from the table above, the oil content in gray water was reduced by 95% using a tricanth centrifuge, which made it possible to reuse it.

Table 2

Water-saving potential

Also, the possibility of saving an average of the following amount of water per household by using purified gray water in the toilet washing system was determined (Figure 1-2).

It was also confirmed that the pH level of purified water is within the range of suitability for technical needs (6.5-8.5). Economic efficiency. In a 100-apartment building, reusing gray water in the toilet washing system alone leads to the following economic benefits per year:

Amount of water saved per year: 4,380 m³

Price per 1 m3 of water (average): 2,500 soums.

Annual savings: 10,950,000 soums

Figure 1. Amount of water saved per day

This means that for a residential building with 100 apartments, it will be possible to save up to 12,000 liters of clean drinking water per day.

Figure 1. Efficiency of the trikanter centrifuge technology

The diagram shows the decrease in fat content: Fat reduction (mg/l)

Advantages of design and system model. New system model built using AutoCad programs: Provided a separate pipeline for the recycled water supply network; Pressure losses and flow directions were optimally calculated; A bypass system has been introduced for emergency situations. These results showed that it is possible to effectively purify gray waters using a tricanth centrifuge and direct them to technical needs. This will significantly reduce drinking water consumption, reduce the environmental burden, and contribute to the introduction of resource-saving approaches in newly built residential areas. The possibilities of saving drinking water, separating fats, and using gray water for technical needs through processing in new multi-story buildings in Tashkent were studied. Compared to previous studies, in this study, a reduction in fats by 95% and BPK by 83.3% was achieved through a tricanth centrifuge. This showed the effectiveness of the physical method in preliminary cleaning. According to the results obtained, a household can save 42% of water per day. It has been established that the centrifuge can be adapted to new houses and is suitable for use in recycled water toilet systems. However, the study was conducted only in new buildings, and the utilization of washing machine water or sediment was not studied. In future research, it is recommended to cover such issues as the use of treated water in green spaces and washing areas, sludge disposal, and the use of the trikanter in combination with other cleaning methods.

Conclusion. The possibilities of saving drinking water and separating oils by processing grey water in new multi-story buildings in Tashkent were studied. It has been established that with the help of a trikanter centrifuge, it is possible to separate fats at a level of 95%, as a result of which it is ecologically and economically significant. Also, it was possible to save up to 42% of drinking water and use recycled water in toilet washing.

The results were assessed as an important solution for environmental sustainability and water conservation. In the future, it is recommended to use such water in green spaces and laundries, as well as to study the possibilities of wastewater disposal and use as an energy source. It has been shown that the introduction of effective and useful technologies in new housing can serve to improve living conditions and save water resources.

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