Thermomechanical Cuttings Cleaner (TCC) Setting the global standard for the treatment of oily waste drill cuttings

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1 Thermomechanical Cuttings Cleaner (TCC) Setting the global standard for the treatment of oily waste drill cuttings

2 THE TCC IS GENERALLY ACKNOWLEDGED, WITHIN THE INDUSTRY, TO BE THE BEST AVAILABLE TECHNOLOGY FROM AN ENVIRONMENTAL STANDPOINT

3 Breakthrough technology for the oil and gas industries Thermtech AS has set the benchmark for treating oil-contaminated drilling waste in an environmentally friendly manner with the thermomechanical cuttings cleaner (TCC). Creative design and rigorous engineering have produced a compact and efficient treatment unit that offers distinct advantages compared with the competition. Direct heating of the waste stream results in maximum energy efficiency. The recovered base oil is comparable in quality to new base oil and so may be directly recycled. The dried solids are clean and suitable for use in commercial applications such as road construction. The TCC can be easily relocated and is ideal for use offshore. The TCC offers rapid start-up and shutdown, which facilitates simple maintenance tasks.

4 The best available technology During drilling operations, drilling fluid (a mixture of base oil and additives) is pumped down to the drill bit to lubricate it, keep it cool and balance the pressure. The drilling fluid (or mud, as it is commonly known) also flushes the rock cuttings from the formation and brings them back to the surface along with other waste such as clay, sand and water. A shale shaker filters out the fluid that can be reused. The remaining waste, however, is considered hazardous in most jurisdictions. It may contain as much as 25 wt% of base oil from the drilling fluid. There are several options for dealing with the drilling waste. Although discharge to sea still remains an option in some regions around the world, it will not in the future. Mechanical equipment such as centrifuges can remove some, but not all, of the oil in the cuttings. With the increased focus on carbon dioxide emissions, incineration is becoming a less popular option. Reinjection into the formations below the seabed loses the commercial value of the base oil. Another alternative is bioremediation, but that cannot produce reusable oil. Alternatively, the base oil can be separated from the other components by thermal desorption. Here, the waste is heated to evaporate the water and, more importantly, the oil. The oil and water vapours are condensed to liquids in a later step. The oil can then be reused and the solids recycled in a commercial application or safely disposed of. How it works The TCC cleans the waste using evaporation to separate the fluids from the cuttings, a thermal desorption technology, but it has a key difference from traditional systems, which transfer heat indirectly from large surfaces that are heated by steam, hot oil or heat tracing. The TCC excels because the waste is heated in a fundamentally different way by friction. The highly efficient TCC flash evaporates the water and oil in a fraction of the exposure time required in indirect dryers. As a result, minimal thermal degradation of the base oil occurs, thus enabling this valuable product to be reused. In addition, the TCC has significant safety advantages over indirect dryers and complies with the latest Ex requirements. EFFICIENTLY CONVERTING HAZARDOUS WASTE INTO VALUE PRODUCTS BREAKTHROUGH TECHNOLOGY

5 THE TCC HAS BEEN SUCCESSFULLY IMPLEMENTED AT SEVERAL WASTE PLANTS AROUND THE WORLD Vapour outlet Material inlet Stator Rotor Mechanical energy input Material bed < The heart of the TCC is a barrel-shaped chamber (the stator) that houses a shaft with a series of hammer arms (the rotor). The rotor is set into high-speed motion by a motor or engine. The rotation forces the heavier parts of the waste to the inner walls of the stator. The rotor s extreme hammering against this material bed creates the friction and thus the heat that evaporates the oil and water. Solids outlet Solids outlet

6 A compelling financial solution INCOME FACTORS COST FACTORS Value of recovered base oil The recovered base oil has a high commercial value because the quality is comparable to that of new oil. Capacity Capacity depends first on engine size; however, in any thermal desorption process, a significant proportion of the total energy consumption is related to changing the water from liquid to gas phase. The capacity, therefore, also depends on the amount of water in the waste (see Figure 1). To minimise energy consumption and enhance the TCC s capacity, we recommend the installation of a mechanical dryer before the TCC. Value of dried solids The solids have a potential commercial value because they are suitable for use in asphalt or coating applications. Alternatively, it may be possible to discharge the dried solids to sea (in the UK, for example, the TCC has no problem meeting the 1% oil-on-cuttings requirement) with no additional costs, or to send them to landfill. Water by weight, % Throughput, t/h 5% oil 10% oil 15% oil 20% oil 25% oil 30% oil Energy efficiency Typically, 95% of the direct energy input is retained. Energy costs (electric) The system will consume around 260/250 kwh per tonne of cuttings when powered by a 450/900-kW electric motor at a solids:water:oil ratio of 70:15:15. Energy costs (diesel) When powered by a diesel engine, the TCC will consume 50 to 60 L of diesel per tonne of cuttings at a solids:water:oil ratio of 70:15:15. The engine can also be fuelled by the recovered oil at remote locations; in this case, the TCC will consume around one-third of the volume of the recovered oil. Manpower Just one operator is required to run the fully automated unit. The logistics of bringing cuttings into the plant and of taking recovered products out should also be taken into account. Maintenance Daily maintenance is easy to perform because of the rapid shutdown and start-up procedures. For major maintenance work, various regimes are offered to suit the operational strategy. < Figure 1: The theoretical output of a TCC. The composition of the cuttings will affect the throughput. At a solids:water:oil ratio of 70:15:15, a TCC will process 2 t/h when powered by a 450-kW engine and 4 t/h powered by a 900-kW engine.

7 THE TCC TYPICALLY YIELDS VERY SHORT PAYBACK PERIODS. WE CAN PROVIDE A SOPHISTICATED BUSINESS CASE MODEL TO SUPPORT YOUR DECISION-MAKING PROCESS AND DETERMINE THE TOTAL COSTS OF OWNERSHIP Drilling waste Vapours Feed hopper Drive unit TCC process mill Cyclone Oil condenser Steam condenser Non-condensible gas < Process summary for the treatment of oil-contaminated drilling waste using a TCC unit. Hydraulic feed pump Recovered water Recovered oil Recovered oil Recovered solids Screw conveyor DELIVERY SPECIFICATIONS We deliver standard or tailor-made diesel or electrically powered units in sizes from 150 to 1000 kw. We can upscale to larger drives on request. The standard unit includes a screening device a mixing tank a drive unit (diesel or electric) a process mill a cyclone devices for further cleaning of the oil vapours condensing systems for oil and water a water oil separator control systems and electrical cabinets. Optional elements include a filtering system for the recovered oil thermal oxidisers a rehydration mill for dry solids. In addition, our sales package includes installation, commissioning, early operational assistance and operator training. With a typical space requirement of just 200 m 2 and a weight of around 35 t (excluding drive), TCC units are highly compact and well suited for offshore applications. Moreover, they can be relocated for operation at another site within just a few days. For additional information on Thermtech and the TCC, please visit our website:

8 Thermtech AS Jacob Kjødes vei 15 NO-5232 Paradis Bergen Norway Phone: Fax: Web: Copyright 2006 Thermtech AS. All rights reserved. Revision: January 2010.