“The comprehensive utilization of solid waste in China has faced tremendous problems in the past. In the next 10 years, the environmental protection work will be even more tricky. The cost of reducing emission’s of traditional pollutants will begin to soar and the pressure will increase. New challenges are on the horizon as heavy metal pollution and environmental risks brought by hazardous, toxic waste continue to rise and are significant, even though old problems must still being faced and addressed. Heavy-metal and industrial site pollution will be long-standing problems” said Chairman of GreenNovo Mr. Ma Liyang, expressing his opinion at the Green Development of Steel Industry Forum celebrating 40th anniversary of reform and opening up on Nov. 30th.
China ranks first in terms of the steel, copper, zinc and lead smelting scale and produces large amounts of heavy-metal-containing flue dust (blast furnace dust, copper, lead, tin smelting dust), hydrometallurgical sludge (lead and zinc leaching sludge by hydrometallurgy, copper- cadmium residue, electroplating sludge, heavy chemical sludge), smelting slag (lead or copper granulating slag), and tailing slag, amounting to 50 million tons each year.
As a pioneer, GreenNovo Environmental Technology Co., Ltd (GreenNovo) strives to recycle this heavy-metal-containing waste and eliminate heavy metal pollution from its source.
Its treatment process includes three steps, first, collect solid and hazardous waste produced by steel, non-ferrous metals, chemical engineering industries. Second, concentrate non-ferrous metal content to 60% through pyrometallurgical enrichment to make it the raw material of hydrometallurgical separation. Third, remove impurity and separation (impurity-removal is the most professional and technical section of GreenNovo). During the pyrometallurgical enrichment process, the impurities harmful to the hydrometallurgical extraction are also beneficiated (like chlorine and fluorine), so they need to be removed. At the same time, hydrometallurgical separation integrated with multi-segment coupling is used for tiered leaching, multi-purification, electrowinning, replacement, SX extraction of indium, bismuth and tin, and finally, the waste water is recycled as well.
In the heavy-metal-containing solid and hazardous waste treatment process, GreenNovo utilizes an energy conservation technology (oxygen-enriched combustion and optimization control technology, in-kiln targeted ejection technology, double layer refractory brick technology, power generation technology using the residual heat of high zinc fumes), environmental protection technology’s (waelz kiln fume desulpurization technology, wastewater recycling technology) and some other technical approach’s (steel dust and non-ferrous metal smelting residue synergic processing technology, waelz kiln anti-ring formation technology, waelz kiln reducing atmosphere control and high purity reduced iron powder extraction technology).
In the future, GreenNovo will keep integrating resources, building a sizeable, professional and industrialized recycling center for metallurgical solid and hazardous waste, making full use of the regional resources so the heavy-metal-containing solid waste can be centralized and be treated.
GreenNovo also provides environmental services for the steel and non-ferrous metal industry and develops recycling and harmless disposal proposals for different kinds of solid and hazardous waste based on their features. It also plans to export its recycling technology to the countries along “the Belt and Road Initiative”. Jointly establishing the pyro factory with waste-generating companies like steel factories, GreenNovo processes the steel dust produced by the steel mills, offers technical solutions, takes charge of the operation, and collects the WOX back to the company for hydrometallurgical treatment.