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The paper is a review of the current situation of waste management in Romania, focusing on solids recovery and recycling. Although some efforts have been made in the Romanian waste sector in order to reach the European targets within the deadlines, the national waste management plan update and waste prevention program implementation are delayed. At the moment, public awareness campaigns are being developed and implemented for recycling, without much emphasis on reduction. However, for now most of the waste ends up in landfills. The current recycling percentages are below 15% of the total municipal solid waste generated, with the lowest landfilling percentage of 69% (based on Eurostat data for 2011-2015). For 2015, Romania had the highest landfilling rate, of 72%, compared to the European Union value of 25.6%. Several separate collection strategies were studied in order to underline the main drawbacks in each case and to identify the optimal options for the given social and economic environment. Solutions for separate collection and waste recycling are being currently implemented in several Romanian regions as case studies under the initiative of local authorities and/or NGO's, without a unitary national approach. The solutions with innovative character and the best practices related to high recovery rates are presented. [ABSTRACT FROM AUTHOR]

Large areas of soil are historically contaminated with petroleum hydrocarbons, mainly due to lack of environmental protection legislation and careless oil extraction in the past. In some cases, one of the potential remedial actions may be the bioremediation of the oil contaminated soil, due to low cost and low environmental impact. The focus of this research paper was to analyze the efficiency of the ex-situ bioremediation of oil contaminated soil at a large scale, in the open air. The investigations were performed by an ex-situ method in a bioremediation plant with a large capacity. Experiments were conducted both in open air (large scale, less controlled environment) and in the laboratory (small scale, controlled environment). Aeration of the contaminated soil was done using a windrow turner that also had a sprinkler system mounted on it for humidity control. Laboratory analysis was conducted at the beginning to check the availability of petroleum degrading indigenous organisms in soil. The hydrocarbons degrading speed was higher in the field trials under laboratory conditions, but only in the first phase. The experiments showed up that the overall remediation speed in a longer period of time tends to be equal in laboratory and in uncontrolled environment. [ABSTRACT FROM AUTHOR]

Ozonation process analysis involves the development of mathematical models. Modeling is the action that reflects a phenomenon which is inaccessible to direct research by using a model elaborated in conditions and means that can guarantee the validity of the results. In the presented study two simulation programs were developed Mathlab Simulink in order to determine the substrate constant consumption and the reaction order. For evaluating the mass transfer and ozone consumption a hydrodynamic model based on the equation of ozone dispersion in water was elaborated using the software package FlexPDE. In the first stage of mathematical model and numerical simulations it was difficult to specify the values of the coefficients entering the dispersion equation, so a series of experiments were conducted in order to calibrate the constants in the equations. The process parameters for the experimental research were: ozone inflow = 5 g/h; wastewater retention time in the ozonation column = 5-80 min, dictated by the provided ozone flow; wastewater inflow = 0.1 -1.6 liters/s. In order to simulate the time variation of the pollutant concentration a Simulink model was designed using library blocks; the parameter values for each block were set according to the corresponding values in the experimental installation. The model analysis was performed by simulation using the Simulink menu bar and viewing the system behavior was realized through the "Scope" window. The time variation of the pollutant concentration was observed in the same time interval as the one in the experiments. Several simulation cases were elaborated based on the ozone dispersion equation to determine the mass transfer coefficient and ozone consumption, considering different orders of reaction n so as to achieve experimentally measured residual ozone values in the ozonation column. For each of the six experimental variants and simulations performed k values were obtained. [ABSTRACT FROM AUTHOR]

The aim of the present paper was to illustrate certain methods and the associated experimental procedures for determining the main defining characteristics of rechargeable batteries that may be used for powering various autonomous sensing devices and also a selection method/criterion to determine the most suitable rechargeable battery to be used in conjunction with the autonomous power supplies. During the rechargeable batteries evaluation process one has also considered the main characteristics of an autonomous system related to the charging and discharging procedure, while the monitoring was carried out using a dedicated software. [ABSTRACT FROM AUTHOR]