E&P
Converting Drilling Waste to Valuable Products: Environmental Friendly and Cost Efficient The downside of drilling oil and gas wells is that it generates hazardous waste. A massive amount of drilling waste i.e. drill cuttings, comes out of the bore hole and as the well drilling gets more and more sophisticated due to the use of special synthetic drilling fluids which drives costs up and, increasing waste volumes due to directional drilling relative to vertical drilling, it is not surprising that the treatment of drilling waste is climbing up on the agenda of various stake holders. With the downturn in the industry there is an obvious focus on reducing and avoiding costs.
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the drill cuttings which meets environmental legislations, recovers the valuable drilling fluids and reduces logistics and disposal costs.
The TCC Solution
The end result of the TCC process are base oils, which are of high quality and are suitable for re-use as a virgin oil, and the mineral part that may be subjected to recycling and be used in various applications (e.g. in road construction, concrete or cement production, asphalt). The TCC is used both on land and offshore.
till, in many parts of the world, due to different legislations, rather unsophisticated solutions are being applied. The drill cuttings are not treated but dumped in a disposal well or landfilled. When drill cuttings are treated, either by a centrifuge or a vertical dryer the treated solids, still containing quite some of the hazardous drilling fluids, are skipped and shipped to landfills. Numerous countries and states have already or are now implementing stringent legislation related to drill cuttings. Total petroleum hydrocarbons (TPH) in solids, emissions and landfill restrictions are watched closely and the industry perception is that taking care about drill cuttings becomes more and more expensive while the desire is to reduce the costs. The Thermomechanical Cuttings Cleaner (TCC), developed by Thermtech, is an advanced thermal desorption solution to treat
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The TCC technology is based on the converting of kinetic energy into thermal energy by creating friction in a Thermtech developed process mill. This process leads to the evaporation of volatile substances, including base oils. Thermtech’s technology ensures the reduction of the contents of oil derivative substances which means that extremely high ecological standards are met, allowing the reduction of drilling waste stockpiles or reinjection of waste products into the ground.
The TCC characteristics The TCC technology has unique characteristics which are the consequence of generating heat through friction. A major differentiator compared to any thermal technology is the extreme short retention time of the waste in the TCC unit which not only results in recovered oil that is comparable to newly created base oils but also in a high processing capacity in a small footprint. A very important effect of the friction process is that it allows for full temperature control meaning temperature stability and the possibility to adjust temperatures immediately when needed to achieve an optimum operation result. The TCC is the only thermal system currently used offshore, in contrast to a variety of indirect methods such as rotary kiln, hot oil units, microwave and induction thermal systems that are either used on land or in development stage Bottom right: Stationary TCC. Below: Mobile TCC for offshore operations.