Spent Oil as a Resource
At one of the largest European processors of toxic waste, the 3-phase technology of GEA Westfalia Separator Group has for many years been the standard process used for treating spent oils and bilgewater containing oil from the hulls of ships. Netherlands-based ATM has already received its fifth decanter of the same type, and has thus been able to significantly boost its processing capacity.
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1.5 million tonnes of toxic waste every year
ATM specialises in treating industrial and hazardous waste. This includes contaminated soil and asphalt granulate - which contains tar that is released when asphalted roads are removed or repaired -, as well as paints, varnishes, chemical waste, effluents, oil sludge and marine waste. In order to treat these waste substances, ATM operates a heat treatment installation, a pyrolysis installation, as well as a sludge treatment installation and a water treatment installation. Every year, 45,000 trucks make deliveries to ATM at their Dutch site in Moerdijk, and the docking facility receives more than 2,000 vessels, which together deliver approximately 1.5 million tonnes of waste for treatment every year. More than 90 percent of this waste is then suitable for being recycled as a product or as raw material. The volumes which are treated mean that ATM is one of the largest processors of hazardous waste in the world. ATM is owned by Shanks Nederland, a group with a further ten waste processing companies. Together with other Shanks waste operations in Belgium and Great Britain they form the Shanks Group Plc., a company listed on the London stock exchange.
In 2003, ATM installed the first 3-phase decanter from GEA Westfalia Separator Group.
Treated fuel used for thermal treatment installations
The thermal treatment installation for treating these waste substances is the largest installation in Europe. It of course uses a lot of fuel, which, however, is completely recovered from the oil and the paint / varnish waste treated in the other installations of ATM. As a result of the synergy between the various ATM installations, no additional fossil-based fuel is required for heating the thermal treatment installation. Some of the fuel is also obtained from treating the bilgewater and spent oil from ships. According to the MARPOL agreement (on maritime pollution), discharging waste substances containing oil into the open sea is prohibited. ATM is able to collect this oil waste by way of a port collection facility. Due to its favourable location between Antwerp and Rotterdam, many ships pass by the location. At one jetty, several vessels can be serviced simultaneously. These spent oil, bilgewater and other waste containing oils are collected in tanks; they are heated, homogenised by means of agitation and, in certain cases, mixed with chemicals in order to split emulsions.
Perfect utilisation of spent oils and bilgewater
This is when the decanters of GEA Westfalia Separator Group come into action. In 2003, ATM for the first time installed a 3-phase decanter of GEA Westfalia Separator Group, namely a CB 635 with a capacity of 20,000 l / h. It separates the oil-solids-water mixture into its three phases in a single operation. The discharged solids are treated in the pyrolysis installation, the effluent is treated in the company’s own waste water treatment plant (a site covering 12 hectares), and the valuable phase - the oil phase with an oil content of more than 98 percent -, is used as fuel for the thermal treatment installation. A perfect solution for treating and utilising spent oils and bilgewater.
Because demand for treatment which complies with all legal requirements is increasing, ATM did not stop at one decanter; in subsequent years, it gradually expanded its spent oil and bilgewater capacities and commissioned two more decanters of the same type. ATM took an even greater step in 2010: the company installed two more 3-phase decanters, one at the beginning and another in the middle of the year, so the waste disposal company now has five identical decanters with a bilgewater processing capacity of 100,000 l / h which can be used around the clock.
The treatment of spent oil is not only an environmental necessity, but when the price of oil reaches 30-40 dollars a barrel; it also becomes an economically interesting source of raw materials. Photos: Joost Vliegen