Presence of Siloxanes in the Biogas of a Wastewater Treatment Plant Separation in Condensates and Influence of the Dose of Iron Chloride on its Elimination

The siloxanes present in the biogas produced during anaerobic digestion damage the mechanism of cogeneration equipment and, consequently, negatively affect the energy valorization process. For this reason, the detection and elimination of these silicon-derived chemical compounds are a priority in the management of cogeneration facilities. In this regard, the objectives of this paper are, firstly, to characterize the siloxanes in the biogas and, secondly, to qualitatively evaluate the influence of the dose of iron chloride on its elimination. The research was performed at the Rincón de León Wastewater Treatment Plant (Alicante, Spain). The outflow biogas of the digesters and of the pressurized gasometers was sampled and analyzed. The results obtained made it possible to demonstrate, firstly, the absence of linear siloxanes and that, of the cyclic siloxanes, the predominant type was decamethylcyclopentasiloxane, and, secondly, that the addition of iron chloride in the digesters significantly reduces the siloxane content in the biogas. Additionally, it was demonstrated that the process of compression of the biogas, with the elimination of condensates, also produces significant reductions in the concentration of siloxanes in the biogas.

Taquicardia ventricular idiopática : estudo de correlação do ECG com o local de origem

Trabalho Final do Curso de Mestrado Integrado em Medicina, Faculdade de Medicina, Universidade de Lisboa, 2014

Turkey's economy: a story of success with an uncertain future. OSW Commentary No. 120, 2013-11-05

In the decade since the Justice and Development Party (AKP) came to power, Turkey’s economy has become synonymous with success and well-implemented reforms. Economic development has been the basis of both socio-political stability inside the country and of an ambitious foreign policy agenda pursued by the AKP. However, the risks associated with a series of unresolved issues are becoming increasingly apparent. These include the country’s current account deficit, its over-reliance on short-term external financing, and unfinished reforms, for example of the education sector. This leaves Turkey exposed to over-dependence on investors, especially from the West. Consequently, Ankara has become a hostage of its own image as an economically successful state with a stable socio-political system. Any changes to this image would cause capital flight, as exemplified by the outflow of portfolio investment1 and an increase in the cost of external debt2 that followed the nationwide protests over the proposed closure of Gezi Park last summer. In addition, Turkey remains vulnerable to potential changes in investor sentiment towards emerging markets.

Russia in Crisis: Year One. OSW Report, January 2010

Economic conditions which had favoured Russia’s development suddenly changed in mid-2008. The Russian economy was hit, on the one hand, by a drastic slump in oil prices (which fell from nearly US$150 to US$50 between July 2008 and January 2009), and on the other by the outflow of investors (a net of US$130 billion of capital left Russia in the fourth quarter of 2008). Within several months, the financial crisis became an economic crisis affecting the entire economy. The financial reserves accumulated in times of prosperity (more than US$162 billion in the stabilisation funds and nearly US$598 billion in the currency and gold reserve) alleviated the negative impact of the crisis, although this failed to prevent the deep declines in macroeconomic indicators. Russia is one of the states most severely affected by the crisis. In the first half of 2009, its GDP fell by 10.4% compared to the same period in the previous year, while industrial production dropped by nearly 15%, and a decrease in investments of over 18% was reported. The poor economic performance has strongly affected the Russian budget, which reported a deficit for the first time in ten years in 2009. During the first year of the crisis (August 2008 – September 2009), Russia’s financial reserves were seriously reduced as a result of the government’s anti-crisis policy and interventions from the central bank: the reserve fund decreased by nearly 45% to US$76 billion, and the central bank’s reserves shrunk by nearly US$200 billion to US$409 billion. Meanwhile, however, the money in the National Welfare Fund, which had been intended almost entirely to subsidise the Pensions Fund between 2010 and 2015, rose almost three-fold (to US$90 billion). According to government forecasts, the money from the reserve fund is also supposed to be spent fully in 2010. The financial crisis has triggered a dynamic outflow of capital from the Russian market. So-called speculative capital was the first to demonstrate the lack of confidence in the Russian market. In the first half of 2009, the growth rate of long-term investments also decreased noticeably, although no spectacular withdrawal of direct investments from Russia has been observed. The economic crisis has also halted the foreign expansion of Russian private capital, while state-owned capital strengthened its position as an investor. Russia’s raw materials companies continue to be the main category of foreign investors; however, new technologies are gaining prominence as the second main direction of Russian investments.