Suchergebnisse

With regard to environmental facilities, blindness and the subjectivity of site selection lead to serious economic, engineering and social problems. A proper siting proposal often poses a challenge to local governments, as multiple factors should be considered, such as costs, construction conditions and social impact. How to make the optimal siting decision has become a topical issue in academic circles. In order to enrich the framework of site selection models, this study combined GIS, AHP and Remote Sensing (RS) technologies to conduct siting suitability analysis of sewage treatment plants, and it was first applied in the Liao River basin in Jilin Province in China. The enriched model is able to reveal blindness in the former site selection of sewage treatment plants and explore optimal siting areas, involving an effective quantification method for summer dominant wind direction and urban stream direction. In a case study, it was found that local governments need to be cautious of the distance of sites from rivers and residential areas and the impact of these sites on downwind and downstream residents. Additionally, siting suitability has obvious regional characteristics, and its distribution varies significantly between towns. Huaide Town shows the largest optimal siting areas and can be given priority for the construction of new sewage treatment plants. This paper developed a more scientific approach to site selection, and the outcome can provide a robust reference for local governments.

This article is devoted to the review of problems with the disposal of sewage sludge. The cleaning of municipal wastewaters leads to the accumulation of a large amount of sediment, which requires a rational and balanced approach to their utilization. Sewage sludge is a valuable energy and material resource that can be used as a secondary raw material. The most popular methods of utilization are: dumping, combustion, used in agriculture as fertilizers, production of building materials. The main technological schemes for utilization of sewage sludge in accordance with these methods are considered. New ways of recycling wastewater used in the world, including land reclamation, quarries and landfills, biogas production and thermal energy, the allocation of valuable elements and metals, as well as adsorbent production, are described. It is established that in the USA and the European Union the predominant amount of precipitates is used in agriculture as fertilizers, and in Japan for the production of building materials. It has been found that using fertilizers on the basis of sewage sludge increases the yield and improves the quality of soil, namely increasing the content of humus. When adding to building materials additive based on the sediment of sewage, a high water resistance coefficient and increased strength. The existing problems connected with the accumulation and utilization of sewage sludge in Ukraine are considered. Most sewage sludge, which are formed on the territory of Ukraine, are subject to dumping on sludge grounds. The possibility of using sewage sludge in the production of building materials and the manufacture of coagulants has been determined. It is established that it is necessary to borrow experience from other countries of the world, in which most of the formed sediments is used as secondary raw material, which allows solving not only environmental protection but also economic task. A promising way to dispose of sewage sludge for Ukraine is the production of substrates for the remediation of technogenically disturbed lands, as well as their use in agriculture. ; Розглянуто проблеми з утилізації осадів стічних вод. Очищення комунальних стічних вод призводить до накопичення великої кількості осадів, що портебує раціонального та збалансованого підходу до їх утилізації. Осад стічних вод є цінним енергетичним та матеріальним ресурсом, який можна використовувати як вторинну сировину. Найпопулярнішими методами утилізації є: захоронення, спалювання, використання у сільському господарстві як добрив, виробництво будівельних матеріалів. Охарактеризовано нові способи з утилізації осадів стічних вод, які використовують у світі, серед яких: рекультивація земель, кар'єрів та звалищ, виробництво біогазу та теплової енергії, виділення цінних елементів і металів, а також виробництво адсорбентів. Встановлено, що у США та країнах Європейського Союзу основну кількість утворюваних осадів використовують у сільському господарстві як добрива, а в Японії – для виробництва будівельних матеріалів. Розглянуто наявні проблеми, які пов'язані з накопиченням та утилізацією осадів стічних вод в Україні. Більшість осадів, які утворюються на території України, підлягають захороненню. Визначено можливість використання осадів стічних вод у виробництві будівельних матеріалів та виготовленні коагулянтів. Встановлено, що в умовах України найперспективнішим методом утилізації осадів стічних вод є використання їх як добрив у сільському господарстві.

Management of sewage sludge has become a topic of increasing importance. This is because the treatment and final destination of these wastes are not growing at the same rate at which generated what is necessary to add the limited storage capacity of wastewater treatment plants or waste transfer centers. Current policies of different governments aims, among others, promote proecological management of sewage sludge, replacing traditional methods by new methods that lead to their stabilization and safe recycling. These methods can lead to the recovery of valuable raw materials from potentially dangerous others in order to permit their use in agriculture, industry or energy production. Moreover, exists a great enzyme market, mainly those with hydrolytic activities such as proteases, lipases or cellulases. Although its use has many advantages, the competitiveness of the enzymes compared with chemicals is limited by its high production costs. The use of a less expensive culture media and the stimulation of the production of these enzymes can significantly reduce production costs. Therefore, the use of tertiary materials as alternative substrates, available in large quantities and at lower cost, is an interesting option. In this work we have studied the effect of pH on the fermentation of sewage sludge by Bacillus licheniformis, a hydrolytic enzymes producer microorganism, in order to obtain several products for specific agronomic applications.