Suchergebnisse

In dem Bericht zur Veränderung und Entwicklung des audiovisuellen Bereichs in Bulgarien seit 1989 werden zunächst die bestehenden Rechtsgrundlagen vorgestellt: das Rundfunk- und Fernsehgesetz, das Konzessionsgesetz und die Gesetzesvorschriften im Bereich der Filmförderung. Das Kapitel, in dem der Strukturwandel in der audiovisuellen Landschaft behandelt wird, stellt die Struktur, den Haushalt und die Programmgestaltung des Bulgarischen Nationalen Fernsehens (BNTN) vor, und beschreibt die neuen Anbieter "Nova Televizia" (NTV) und "Television 7 Dui" (7 Tage) und einige lokale Fernsehkanäle. Der Bereich der Kabelkommunikation ist derzeit noch nicht weit entwickelt, was auf die unklare Rechtslage zurückgeführt werden kann. Die Darstellung des Wandels im Bereich der Filmproduktion und des Filmverleihs schließt das Kapitel, dem die Darstellung der Marktsituation, d.h. des Zuschauerverhaltens folgt. Im letzten Abschnitt werden die wichtigsten Trends und Fakten noch einmal zusammengefaßt. Der Mangel an einer soliden Rechtsgrundlage ist nach Ansicht der Autoren das größte Problem des audiovisuellen Bereichs, insbesondere des Fernsehens in Bulgarien. (PT)

Deterioration of water quality is a major problem world widely according to many international non-governmental organizations (NGO). As one of the European Union (EU) countries, Bulgaria is also obliged by EU legislation to maintain best practices in assessing surface water quality and the efficiency of wastewater treatment processes. For these reasons studies were undertaken to utilize ecotoxicological (Microtox(®), Phytotoxkit F(TM), Daphtoxkit F(TM)), instrumental (to determine pH, electrical conductivity (EC), chemical oxygen demand, total suspended solids (TSS), total nitrogen (N) and phosphorus (P), chlorides, sulphates, Cr, Co, Cu, Cd, Ba, V, Mn, Fe, Ni, Zn, Se, Pb), as well as advanced chemometric methods (partial least squares–discriminant analysis (PLS-DA)) in data evaluation to comprehensively assess wastewater treatment plants' (WWTPs) effluents and surface waters quality around 21 major Bulgarian cities. The PLS-DA classification model for the physicochemical parameters gave excellent discrimination between WWTP effluents and surface waters with 93.65% correct predictions (with significant contribution of EC, TSS, P, N, Cl, Fe, Zn, and Se). The classification model based on ecotoxicological data identifies the plant test endpoints as having a greater impact on the classification model efficiency than bacterial, or crustaceans' endpoints studied.

Abstract
Background
The management of sludge from municipal wastewater treatment plants (WWTPs) is a global issue, but also an opportunity for circular reuse. Recent data show that sludge reuse in agriculture has the highest share of all utilization routes in the EU. Council Directive 86/278/EEC on the spreading of sludge in agriculture, adopted more than 35 years ago, is still relevant, notwithstanding the discussion on the need to update it. Extracting critical, strategic, and precious metals and metalloids from sludge is an alternative for sludge reuse, which offers several benefits, such as avoiding the high environmental and health risks associated with using sludge directly in agriculture. Additionally, it allows for the recovery of metals, including those listed as Critical Raw Materials by the European Commission. To implement this alternative, it is necessary to first assess the metal content in the sludge and then develop economically and technically viable technologies. In this study, the content of chemical elements in the sludge of eight full-scale WWTPs in Bulgaria is analysed with focus on: (1) assessing the suitability for agricultural application by evaluating the content of macro- and micronutrients and hazardous metals; (2) assessing the possibility of using the sludge as a source of critical and precious metals.

Results
For the main nutrients, the following contents as a percentage of the sludge dry weight (DW) were recorded—2.06% to 6% for N, 1.52% to 2.67% for P and 0.47% to 0.81% for K, which are in line with case studies of successful sludge application in agriculture. Only sludge samples from two WWTPs exceeded the permitted limit for hazardous metals and metalloids. On the other hand, of the 21 metal and metalloid constituents listed in the EU Critical and Strategic Material (CRM) list, at least one of the examined samples has a content above 10 mg/kg for 15 elements. The average contents in mg/kgDW of Au (1.1), Al (19,272.9), Mg (6677.6), Ti (1730.9), Ga (20.9) and As (16.6) measured in the investigated WWTPs are among the highest or second highest reported in other countries.

Conclusions
The results of the study show prospects for optimising and improving the reuse of sewage sludge in Bulgaria. Sewage sludge from most WWTPs has potential for agricultural application due to its high nutrient content. Large amounts of accumulated critical and strategic metals, gold and silver are trapped in Bulgarian sewage sludge, indicating that sewage sludge could be considered an alternative source with high potential for these valuable elements.