Land fill to resources
We use our copper smelting facilities and technology to process shredder residue from used vehicles and discarded home appliances, as well as other types of industrial waste. We actively engage in material recycling (recovering valuable metals) and thermal recycling (recovering heat), and fix other elements into stable forms such as slag, to achieve zero-emissions recycling and make use of all resources previously sent to landfills.
Detoxify specially controlled industrial waste
Hosokura Metal Mining Company, which handles Mitsubishi Materials' lead smelting operations, utilizes a blast furnace previously used to process lead minerals. In addition to treating used vehicle batteries and lead scrap, Hosokura Metal Mining detoxifies specially controlled industrial waste, including difficult-to-process lead.
Highest in the world of processing capacity
Discarded circuit boards from various types of electronic devices are commonly referred to as E-Scrap and contains high concentrations of gold, silver, copper, palladium and other valuable metals. Accordingly, in recent years E-Scrap has attracted increasing attention as a new and valuable source of raw materials for smelting. Furthermore, amid growing environmental concerns, the amount of E-Scrap recovererd is expected to increase in line with the higher recycling rates of home appliances and other items. Our Naoshima smelter and Refinery, taking advantage of the Mitsubishi Process for continuous copper smelting, a unique technology for smelting precious metals with the lowest environmental impact in the industry, has been promoting the expansion of E-Scrap receiving and processing. In June 2015, we began further expansion of E-Scrap treatment facility. Slated for completion in April 2016, the expansion will augment the Naoshima Smelter and Refinery's E-Scrap acceptance and processing capacity to 110,000 tons per year--the highest level in the world. Group company Onahama Smelting and Refining Co., Ltd., also began processing E-Scrap in September 2013 and is increasing its processing volume.
Safety and stable processing at cement plant
We employ a method of introducing sewage sludge directly into cement kilns. The process from acceptance through processing is completely sealed, from receipt of sewage sludge through introduction into cement kilns.
Each of plants is authorized to process contaminated soil
We accept waste soil generated during construction for use as a cement raw material. Each of our plants is authorized to process contaminated soil. This soil is processed at high temperatures (around 1,450°C) in cement kilns, and all is recycled as cement.
Recycle as raw material of cement
We accept the coal ash generated from coal-fired thermal power plants and use it as a raw material for cement. Ash is brought to our inland plants by jet pack cars (dry ash) and dump trucks (wet ash), while our coastal plants receive ash via cement tankers (dry ash) and general cargo vessels (wet ash). Using cement tankers for both cement and coal ash allows us to haul materials on both inbound and outbound trips, greatly increasing transport efficiency.
Conversion of incineration ash to cement resources
We use the incineration ash generated by municipal bodies' refuse incineration plants as cement raw materials.
Our Kyushu Plant handles large-scale conversion of incineration ash to cement resources by removing the metals and chlorine content from incineration ash.
Effective use as thermal energy
We put large volumes of waste tires, either as round tires or chipped waste, to effective use generating thermal energy. The steel cords from tires are also used as a source of iron.
Effective use as thermal energy
We receive the waste plastic generated by various industries, using its thermal energy effectively as an alternative to coal and other fuels. Our plants are all equipped with crushers, allowing them to handle various types of packaging.
Process waste liquid at site
To process waste acid, waste alkali and other waste liquids, after placing the liquids in specialized tanks they are brought to kilns for incineration.
Recycle as cement resources
Mitsubishi Materials has developed and commercialized a proprietary technology for stably recycling powdered waste gypsum board as cement raw materials by firing it at high temperatures in cement kilns.
This technology prevents the generation of hydrogen sulfide and other hazardous substances that were a concern during processing at landfills. In addition, waste gypsum board powder can substitute plaster to be added at the final stages of the cement production process, thereby also helping to achieve resource savings.
aluminum beverage cans are highly recyclable
Aluminum beverage cans are environmentally friendly containers, as they are highly recyclable and have excellent resource- and energy-saving characteristics. Used beverage cans (UBCs) can be recycled numerous times in a can-to-can process. Recycled aluminum ingots can be produced with only around 3% of the energy required to produce new ingots, playing a substantial role in helping to reduce global warming. In the 1970s, the Mitsubishi Materials Group was an industry leader in the recycling of aluminum cans. In 2001, we began operating a plant to collect UBCs and produce rolled slabs directly from can materials. We have created a fully integrated UBC processing system to handle everything from can material rolling to aluminum can production within the Group.
Recycling rare metal to ingots
Mitsubishi Materials makes full use of its copper smelting process facilities, by undertaking recycling activities that process scrap as secondary materials containing copper and precious metals. The Mitsubishi Materials Group has in place a network that enables the recycling of essentially all valuable metals, including lead, tin and rare metals, into ingots. In addition, we have the technological capability, such as the ability to stabilize toxic substances, to further enhance our recycling business.
We are making full use of our network and recycling technologies with the aim of realizing a recycling-oriented society, by operating an integrated system, spanning the assessment, collection and processing of recycled materials.
Challenge to zero-emissions
A request from Kagawa Prefecture for Mitsubishi Materials to use the site of Naoshima smelter and Refinery to establish their incinerator to dispose 500,000 tons of industrial waste illegally dumped on the island of Teshima, provided an opportunity to cultivate a new environmental industry in the town of Naoshima. We worked with Kagawa Prefecture to formulate the Naoshima Eco-Town scheme, which was authorized by the national government in March 2002.
In this Eco-Town scheme, Mitsubishi Materials operates a circular resource recovery business, consisting of an intermediate processing facility for Teshima and other waste; a molten fly ash recycling facility to pretreat the molten fly ash generated by municipalities both on and off the island; and a valuable metal recycling facility constructed for the pretreating (incineration melting) shredder residue before sending to the copper smelting facility. The result is zero-emissions recycling scheme that makes effective use as resources such as molten fly ash, shredder residue, and other substances, which were previously sent to landfills.
Objective sampling by automated facilities
For fair and accurate appraisal of scrap materials, Mitsubishi Materials uses many different types of sampling systems and selects the apptopriate method of each type of various scrap materials. Our sampling systems are all fully automated for the entire process, which therefore enable objective sampling.
Establish non-polluting system by Mitsubishi Process
Conventional copper smelting employs many different types of stand-alone furnaces: a flash furnace or reverberatory furnace, multiple converting furnaces, and anode furnaces. Molten metal at temperatures typically over 1200°C istransferred between furnaces by using a large ladle and transported by crane in batches.
The Mitsubishi Process for continuous copper smelting uses launders to transport metal between the smelting furnace, slag cleaning furnace and converting furnace, and finally to the anode furnaces. As a result, we have succeeded in creating a process that is continuous rather than batch-based. This approach allows facilities to be more compact, and reduces energy and operation costs. The conventional method leaked sulfur dioxide gas when molten metal was transferred between furnaces using a ladle. The use of launders made the need for ladles obsolete, resulting in a non-polluting system.