Three New Waste Water Treatment Plants in Romania
All good things come in threes (for the time being). In Romania, HOCHTIEF Construction AG is currently building three new waste water treatment plants in three medium-size cities. For all three new installations, HOCHTIEF Construction has awarded the contracts for the engineering for dewatering, and in one case also for thickening by means of decanters, to the GEA Westfalia Separator Group.
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Waste water treatment plants with sludge dewatering
Since joining the European Union (EU) in 2007, Romania has been receiving regional policy subsidies from Community funds. The aim is to bring the standard of living up to the level of the other countries in the EU, and also to encourage a balanced development throughout the entire country. Of the 21.5 million Romanians, more than half are already living in cities, with increasing numbers of young Romanians leaving their homes and moving to the cities.
The EU subsidies focus particularly on water treatment and environmental investment. These programmes also cover the construction of municipal waste water treatment plants in three cities. The German construction company HOCHTIEF Construction AG has been awarded the contracts for constructing waste water treatment plants with sludge dewatering. As a complete provider and operator of environmental installations, HOCHTIEF Construction has provided an impressive demonstration of its efficiency in the construction of more than 100 waste water purification and treatment plants (so far) for a wide range of sizes. And the GEA Westfalia Separator Group has been successful with its bids for the contract for mechanical separation technology in all three projects.
Strong demand for waste water treatment plants in Romania
Following several years of impressive GDP growth, and achieving 7.1 percent growth most recently in the year 2008, Romania was directly affected in 2009 by the international economic crisis, and reported negative growth of the same extent. However, slightly positive growth is expected for 2010, and stronger growth is being forecast for 2011. Demand for waste water treatment plants in Romania is very strong, and a flourishing economy is one of the factors in this respect. Approximately 30 percent of the population is still not connected to drinking water supplies or waste water disposal systems. Approximately 50 cities continue to discharge their untreated waste water into rivers or the Black Sea. Around half of all existing waste water treatment plants do not comply with EU requirements. It is intended that the EU standards will be implemented in all municipal waste water treatment plants by the year 2018. This will require not only the expansion and modernization of existing plants, and the construction of new waste water treatment plants, but also investment in the expansion of the entire sewerage system.
Complete installations for sludge thickening
The companies involved will have to cope with a wide range of tasks in the three cities. The city of Giurgiu was formerly the final destination of the Orient Express. With its more than 70,000 inhabitants, it is situated in the South of the country on the Danube, directly on the border to Bulgaria. The waste water of the city was previously treated only by mechanical means, before being discharged into the sewerage system. In future, the solution will comprise a mechanical as well as a biological treatment arrangement for 82,000 population equivalents; the arrangement will use decanters to thicken the sludge, which will then be digested and dewatered. A gas storage facility will be built for the gas recovered from the digestion process.
In order to thicken the sludge, the GEA Westfalia Separator Group, which is listed as a “preferred supplier” by HOCHTIEF Construction, plans to supply two UCD 346 decanters as complete installations, together with the entire peripheral equipment such as the polymer installation, sludge pump, conveyor scroll, thickened-sludge pump, control units and regulating equipment. Each of these two decanters can thicken 17 cubic metres of sludge per hour to 11 percent dry matter.
Two UCD 305 decanters (“Crocodile“) are used for subsequent dewatering of the digested sludge; each of these decanters dewaters 6 cubic metres of sludge per hour to 25 percent dry matter, thereby achieving a considerable reduction in the overall volume of sludge. This is because there is an inverse relationship between the dry matter and the water content, resulting in lower volume and less weight, with a positive impact on transport as well as landfill costs for the efficiency of sludge incineration. For this reason, HOCHTIEF Construction and the municipal clients have specified relatively ambitious targets for dewatering, so that the new waste water treatment plant to be built can cope with all future demands.
Decanter UCD 305
Total package for two further cities
As part of the bidding process for the Giurgiu waste water treatment plant, the GEA Westfalia Separator Group put together a total package, which also comprises the construction of two further waste water treatment plants in the cities of Slatina and Medias. Slatina has approximately 80,000 inhabitants, and is located in Wallachia, in the South of Romania on the banks of the river Olt. Medias is an important communications junction in Transylvania, in the centre of Romania, with approximately 54,000 inhabitants. The sludge thickening process for the Slatina waste water treatment plant (71,700 population equivalents), as well as for the Medias plant (74,000 population equivalents) does not operate with decanters, but instead uses a static solution. For the dewatering process, the GEA Westfalia Separator Group is supplying two complete UCD 346 decanters to Slatina, each with a capacity of 10 cubic metres per hour, and is supplying two UCD 305 decanters to Medias, each with a capacity of 6 cubic metres per hour. Again, in both of these cases, the solution will achieve dewatering to 25 percent dry matter. It is intended that the three municipal waste water treatment plants will be commissioned successively in May, August and November 2011.
Assurance of project management
In addition to the technical advantages of the two compact and modern decanter types used, UCD 305 and UCD 346, the wide range of experience in environmental applications and in particular project management assurance were key criteria for deciding in favour of the GEA Westfalia Separator Group. With project management, the GEA Westfalia Separator Group is able to handle the design and construction of machines in Germany; however, with its subsidiary in Bucharest, it is also able to handle installation and commissioning and, a very important aspect, after-sales service. In addition, the GEA Westfalia Separator Group can also point to numerous reference installations in environmental technology in Romania as well as many other countries in Eastern Europe. Three years after joining the EU, Romania is starting to hugely expand its waste water processing systems. The GEA Westfalia Separator Group has made a successful start with these three projects.