Waste Processing

MET Advanced Technology Microwave Ovens: Waste Processing

The Waste Treatment developed by MET Microwave is a system designed especially for healthcare organisations generating clinical waste in the healthcare sector, enabling on-site sterilisation and disposal of biohazardous substances. Microwave can be used alone or pooled with various oxidants and catalysts, it can also be combined with some advanced oxidation processes such as UV (photolysis) or photocatalysis (UV/titanium dioxide, TiO2). In the old times, microwave was only coupled to H2O2 to destroy contaminants. Therefore, microwave technology opens up new areas to seek advanced catalytic degradation.

To enhance the degradation of organic pollutants under microwave, various microwave absorbing materials with high surface area and wide pore size distribution have been developed. After using a microwave absorbing material, for example activated carbon, hot spots are formed on the surface of this carbon; thus, it produces selective heating, which promotes molecular rotation and eventually reduces the activation energy. Furthermore, the efficiency of microwave on reducing pollution is strengthened through the coupling of microwave with photolysis and photocatalysis. A basic understanding of microwave theory, its application in eliminating environmental pollution, and various combinations of microwave application, such as combining microwave with other treatment techniques, are useful for treating water as well as wastewater. There are various processes to do this, but microwave technology is a faster and effective way to do it.

Microwave is a powerful tool in the degradation of various organic compounds, including pesticides, ammonia nitrogen and organic dyes. The energy of one mole of photon energy from microwave in the frequency range 1-100 GHz is equal to 0.4-40 J. However, since the energy of the microwave is not sufficient to degrade chemicals, some compounds are needed for the microwave to couple to the bonds of many organic compounds. Therefore, MW has been combined with adsorbents, catalysts and advanced oxidation processes to increase the treatment efficiency of various pollutants and also to shorten the reaction time.

Applications of Microwave Technology in Waste Water Treatment

Sludge Treatment in Microwave

Oxidation Process

Sewage sludge has a large amount of recycling carbon and nutrients. The only thing that needs to be managed is to develop a sustainable management strategy that can effectively recover these nutrients and carbon sources and at the same time produce a useful product. This problem has been solved at the University of British Columbia. They developed an application of a microwave-enhanced advanced oxidation process (MW/H2O2-AOP) for nutrient release and solids degradation from solid waste sludge. The large volume of sludge as an end product is one of the biggest problems in the wastewater treatment industry. The treatment and disposal of waste sludge from wastewater treatment plants can account for 50-60% of the total cost of wastewater treatment. However, the processes are that the residual sludge is digested, incinerated, deposited in landfills, or used as fertilizer by farmland application. To effectively handle and process this residue, work is needed; therefore, an advanced oxidation process (MW/H2O2-AOP) for sludge treatment has been developed at the University of British Columbia. Most of the sludge-suspended solids were disintegrated at temperatures of 80 °C and above. Significant amounts of nutrients and metals were also released into the solution.

Advantages

Industrial microwave waste treatment offers many advantages over conventional waste treatment methods. Some of the advantages are:

• Faster Processing: Microwave energy allows for rapid heating and breakdown of waste. This shortens the processing time and allows the waste to be processed quickly.
• Less Space Requirement: Microwave waste treatment requires less space than conventional methods. This optimizes the use of space and allows waste treatment plants to be built in smaller sizes.
• Less Environmental Impact: Microwave waste treatment causes less environmental impact than conventional methods. This contributes to environmental protection efforts.
• Higher Efficiency: Microwave waste treatment allows you to obtain a higher yield from waste. This allows resources to be utilized more effectively.
• Lower Operating Costs: Microwave waste processing has lower operating costs than conventional methods. This allows waste processing facilities to be operated more economically.
• Suitability: The microwave waste treatment process can handle many different types of waste. This allows waste from different industries to be processed more effectively.

These advantages have led to industrial microwave waste treatment becoming a popular method.