Final Report Summary - MICROCLEANMUD (Microwave cleaning of drilling mud and oil containing hazardous waste) Executive summary: The MICROCLEANMUD project will demonstrate an innovative and energy-efficient method of cleaning oil contaminated drill cutting (DC) from the oil industry and oil contaminated land filling. Our process is based on the utilisation of microwaves (MW) in a compact two-stage process line. Currently there are 70 oil and gas exploration / production rigs drilling in the North Sea and approximately 240 floating drilling rigs operating in the global industry. Totally there are several thousand drilling rigs where approximately 2 400 rigs are drilling for oil and gas in North America. The waste from the drilling process is a slurry of rocks, clay, sand and drilling mud. In 2004 more than 45 000 tonnes of DC were brought onshore. From 2003 and onwards Western European countries are expected to spend on average between 0.5 to 1.5 % of gross domestic product (GDP) on soil remediation, primarily in the agricultural sector, industrial plants, land development and municipals. In Western Europe there are more than 600 000 contaminated sites with a market of about EUR 50 billion p.a. Thus there is a huge need for cost-effective solutions to clean oil contaminated wastes. The use of MW will be cost efficient and have a low degree of maintenance compared to the current solutions available. MCM aim to comply with the European Waste Catalogue 2002 and clean the waste to an oil content (OC) > 0.1 %. Project context and objectives: The main objectives of the MICROCLEANMUD project were to demonstrate an innovative and energy-efficient method of cleaning DCs and land fillings contaminated with oil. The process used in MICROCLEANMUD uses MWs in a compact, two stage processing line. This will provide a low cost solution for the oil industry, as it will require a low degree of maintenance, compared to current solutions available. The project objectives were: Scientific objectives: (1) To get enhanced knowledge about the dielectric properties of crude oil and drilling mud oil as a function of temperature mainly at 915 MHz to ensure a rapid, even and careful heating and to avoid cracking in the first stage of the process. We need to understand the limitations and requirements for all elements that form part of a < 0.1 % MW processing plant for continuous operation. We need to get the necessary general system understanding early in the project to know the trade-offs and focus on the integrated performance. (2) To build a laboratory three-dimensional (3D) simulation model in order to model the interactions between the MW electromagnetic field density distribution and in the first instance the boundary conditions created by cavity (chamber). This model will then be extended to include the movement of residue into the chamber and the adoption of a steady state process (i.e. 50 or 5 000 kg / hour). The purpose of building such a model is to allow the design of the optimum equipment design, for example, the detailed structure of the chamber to ensure rapid and even heating. It will also allow the process to become 'scalable' i.e. once built the model will optimisation of the 5 000 kg / hour system design. (3) Investigate the use of steam as inert gas with recycling to reduce heating time. Steam will be fed back into the start of the process. The goal is to operate with inert gas only when starting the plant until steam is generated in less than a minute. Technological objectives: (1) To design and build a material feed system and sealing capable of 50 kg / h continuous operation to work with the prototype plant. (2) To design and build an automated control system with multipoint temperature measurements with feed rate control capable of closed loop process control of the process to within +/- 200 degrees of Celsius to maximise extraction while avoiding cracking. (3) To design and build a reaction chamber (cavity) using a conveyer that also stir the feedstock and the magnetic field for even heating and free flow of volatiles and to keep temperature differences in the volume of the feedstock within +/- 20 degrees if Celsius. (4) To design and build a MW waveguide/applicator with optimum match which requires cleaning no more often than every 20 hours of operation and loses no more than 5 % of energy efficiency over a 20 hour period. The system integration objectives were: (1) To successfully achieve project integration objectives, 'completed and industrial validated against specification and objectives', within the project 24-month duration. (2) To hold quarterly board meetings including exploitation, dissemination and technical boards. Project results: During first year of the project the design of the feeding system, reactor, chambers, and the control system was carried out. We also at laboratory demonstrated that MWs can be used to reduce the OC of cuttings to the 0.1 % target. A range of representative DC samples from the off shore sector and oil sludge from land fillings have been analysed with regards to the chemical composition and the energy requirements for reaching the desired OC levels. Furthermore, we have carried out advanced MW simulations to ensure the optimal design of the reaction chambers. In order to optimise the utilisation of energy generated with MWs, we have investigated the possibility of mixing MW absorbers into the reactor chambers. This has resulted in the development of spherical MW absorbers that will be fed into the reactor chambers to distribute the energy throughout the process. We estimate that this will lower the power consumption by at least 20 %. In this manner, the total energy consumption will be < 150 KW / ton of processed materials. During second year of the project we have proceeded with more detailed design of the above and built / integrated prototypes of grinder / feeder, material handling, prototype of inert gas system, control system with developed control algorithm. Additions to the functionality of the control system were made and the adoption from its original specification allowed the scientists more freedom to do partial experiments. Also remote access was set up to minimise the cost for software updates. The system worked and proved to be reliable and able to be used, controlled both locally and remotely from other countries. The reduction in system components during this design and proving phase allowed the estimated costs to be reduced but they were still over the original consumables budget of EUR 124 000. The configuration, monitoring, presentation and logging part, using PLC and WinCC, can also be used in the full scale system. But it can also be replaced easily by a more customised system, such as a touch screen interface or a panel with buttons and indicators, or even integrated into more complex industrial control systems such as a SCADA. Due to the complexity of the prototype system and issues at the integration, commissioning and testing phase, the test and validation tasks are delayed but ongoing. Therefore we have been unable to validate the whole system. However, the preliminary result of the treated solid fraction has been described and a theoretical assessment of the expected liquid fraction performed, using a process simulation model. Both demonstrate that the basic principles and components of MICROCLEANMUD are sound, although more work is needed to validate the total system as a working prototype. Potential impact: The aim of the MCM project is to develop a MW-assisted cleaning system that environmentally and efficiency cleans and recycles organic oil from DCs and soil from the offshore drilling and soil remediation industry, respectively. The outcome of the project will primarily impact on the European Hazardous Waste services market, both economically and also provide them with means to be able to fulfil the required legislation. The hazardous waste service industry is probable going to face tougher action from the legislature powers in both individual countries as in the European Union (EU). In more than a decade this has been the case. In addition, there has been a significant growth of volume and increasing complexity of the hazardous waste due to an undergoing change from an expanded definition of hazardous waste. This will create a demand in the need for new technology. Economically the companies in the sector will be able to have substantial savings by using the MICROCLEANMUD equipment, through its improved efficiency and reduced costs. The outcome of the project is also foreseen to have an environmental impact. The technology will produce cleaner waste, thus reducing the land fill contamination. Also the energy used during the processing will be reduced. In addition, it provides a safer and healthier work place by producing no hazardous outlets and cleaner waste. Contact details: Mr Jan-Olaf Bommen RETURA AS Økernveien, 94 0579 Oslo Norway E-mail: jan.olaf.bommen@sim.as List of websites: http://www.microcleanmud.com Related documents Final Report - MICROCLEANMUD (Microwave cleaning of drilling mud and oil containing hazardous waste)
