Recycling gas drilling is a new drilling technology. This paper can be divided into three parts, with the purpose of introducing and analyzing the characteristics of this new technology. First, the major equipment cha...Recycling gas drilling is a new drilling technology. This paper can be divided into three parts, with the purpose of introducing and analyzing the characteristics of this new technology. First, the major equipment characteristic of this technology was introduced. Secondly, compared with conventional gas drilling, Angel＇s model was used to analyze the wellbore flow characteristics. Due to the closed loop and the effect of back pressure caused by the equipment, the gas flow rate decreases dramatically during drilling. Apart from this, it is also found that the kinetic energy at the casing shoe is always smaller than that at the top of the collar. The proposing of the drilling limit concept points out the basic difference between the two gas drilling technologies. Lastly, according to the results of the theoretical analysis, gas supplement operations for the wellbore must be conducted. Thus, two gas supplement schemes are presented in this paper, to provide some guidance for field operations.展开更多
In order to improve the refining effect of zinc ore and promote the development of this industry,taking the hydrometallurgical zinc smelting process as an example,this paper first establishes a model for the recycling...In order to improve the refining effect of zinc ore and promote the development of this industry,taking the hydrometallurgical zinc smelting process as an example,this paper first establishes a model for the recycling of waste residues in the hydrometallurgical process,proposes optimization measures based on proven comprehensive recycling technology for purifying residues to obtain higher valuable metal recovery rate,and provides reference for those in relevant fields.展开更多
Copper-indium-gallium-diselenide(CIGS)is a fast-evolving commercial solar cell.The firm demand for global carbon reduction and the rise of potential environmental threats necessitate spent CIGS solar cell recycling.In...Copper-indium-gallium-diselenide(CIGS)is a fast-evolving commercial solar cell.The firm demand for global carbon reduction and the rise of potential environmental threats necessitate spent CIGS solar cell recycling.In this paper,the sources and characteristics of valuable metals in spent CIGS solar cells were reviewed.The potential environmental impacts of CIGS,including service life,critical material,and material toxicity,were outlined.The main recovery methods of valuable metals in the various types of spent CIGS,including hydrometallurgy,pyrometallurgy,and comprehensive treatment processes,were compared and discussed.The mechanism of different recovery processes was summarized.The challenges faced by different recycling processes of spent CIGS were also covered in this review.Finally,the economic viability of the recycling process was assessed.The purpose of this review is to provide reasonable suggestions for the sustainable development of CIGS and the harmless disposal of spent CIGS.展开更多
Electric arc furnace dust(EAFD)is a hazardous waste but can also be a potential secondary resource for valuable metals,such as Zn and Fe.Given the increased awareness of carbon emission reduction,energy conservation,a...Electric arc furnace dust(EAFD)is a hazardous waste but can also be a potential secondary resource for valuable metals,such as Zn and Fe.Given the increased awareness of carbon emission reduction,energy conservation,and environmental protection,hydrometallurgical technologies for the detoxification and resource use of EAFD have been developing rapidly.This work summarizes the generation mechanisms,compositions,and characteristics of EAFD and presents a critical review of various hydrometallurgical treatment methods for EAFD,e.g.,acid leaching,alkaline leaching,salt leaching,and pretreatment–enhanced leaching methods.Simultaneously,the phase transformation mechanisms of zinc-containing components in acid and alkali solutions and pretreatment processes are expounded.Finally,two novel combined methods,i.e.,oxygen pressure sulfuric acid leaching combined with composite catalyst preparation,and synergistic roasting of EAFD and municipal solid waste incineration fly ash combined with alkaline leaching,are proposed,which can provide future development directions to completely recycling EAFD by recovering valuable metals and using zinc residue.展开更多
The aim of this study is to enhance the recycled PVC （polyvinyl chloride） related material property by formulation technology and develop the recycling product processing technology furthermore develop the chemical ...The aim of this study is to enhance the recycled PVC （polyvinyl chloride） related material property by formulation technology and develop the recycling product processing technology furthermore develop the chemical recycling technology for last stage of PVC wastes. The formulation technology is composed of pre-treatment （crushing, separation etc.） and post-treatment （material ratio, additives, stabilizer etc.） to enhance the recyclate property. The formulation for recycled PVC by application basis and processing technology is applied to produce the structural product for civil and construction application such as pipe fittings and water drainage cap for environmental waterway. Also chemical recycling technology for end life PVC scrap which causes environmental pollution by incineration or landfill is studied for producing hydrocarbon and hydrogen chloride for VCM.展开更多
Tanneries reusing wastewater by combination of conventional and advanced Reverse Osmosis (RO) treatment technologies were assessed for technical and economic viabilities. Conventional treatment methods such as neutral...Tanneries reusing wastewater by combination of conventional and advanced Reverse Osmosis (RO) treatment technologies were assessed for technical and economic viabilities. Conventional treatment methods such as neutralization, clari-flocculation and biological processes are followed to clean the effluents before feeding to RO membrane modules. The characteristics of untreated composite effluents such as pH, biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), total dissolved solids (TDS), and total chromium were in the range of 4.00-4.60, 680-3600 mg/L, 1698-7546 mg/L, 980-1480 mg/L, 4200-14500 mg/L, and 26.4-190 mg/L, respectively. Inorganic ions like Ca2+, Na+, Cl– and SO42– were found more in the wastewaters. Conventional treatments significantly removed the organic pollutants however failed to remove dissolved inorganic salts. Membrane technology removed the salts as well as remaining organic pollutants and the product water is reused in the process. The studied tanneries (5 numbers) have achieved 93-98%, 92-99% and 91-96% removal of TDS, sodium and chloride, respectively. Seventy to eighty five percentage of wastewater was recovered and recycled in the industrial processes. The rejects are subject to either solar evaporation system or Multiple Effect Evaporation (MEE) technology. The resulting salts are collected in polythene bags and disposed into scientifically managed secured land fill (SLF) site. The cost of wastewater treatment for operation and maintenances of RO including the pre-treatments (conventional methods) is INR 100-110 m-3.展开更多
Water is the basis in ecological residential area. It is very important to recycle the water resource in the designing and planning of the ecological residential quarter due to the critical way to realize the wastewat...Water is the basis in ecological residential area. It is very important to recycle the water resource in the designing and planning of the ecological residential quarter due to the critical way to realize the wastewater resource utilization. In this paper, a new technology of wastewater treatment is introduced, which is ORGANICA ecotechnology. We integrate the traditional wastewater treatment technology and modern ecological engineering technology together and apply the integrated technology in the treatment of domestic sewage. The treated water can be reused for landscape and greening, which can beautify the residential area and recycle wastewater.展开更多
The present study dealt with relationships between the degradation and humification process that the organic matter underwent during bacteria-mineral technology. An inverse correlation was found between the protein, l...The present study dealt with relationships between the degradation and humification process that the organic matter underwent during bacteria-mineral technology. An inverse correlation was found between the protein, lipid, and some of the humification indices considered, suggesting that the humification theory is actually humic substances produced from simple-structured natural organic substrates. Weight-average molecular weight （Mw）, number-average molecular weight （Mn）, and the ratio Mw/Mn of dissolved organic matters at different stages of the process were measured by gel permeation chromatography. The results showed that Mn and Mw increased with reaction time from 352 to 17,191, and from 78,707 to 104,564, respectively. The ratio of Mn/Mw decreased from 223.3 to 6.1. This reflected the growth of the polymerization degree of dissolvable organic matters in the process; furthermore, it indicated the formation of complex molecules （humic substances） from more simple molecules. Bacteria-mineral water （BMW） （the effluent of the process） treatments can exert hormone-like activity for enhanced seed germination of wheat and rice and greatly improved chlorophyll synthesis in wheat and rice leaves, Major polyamines （plant regulators） putrescine, spermidine, and spermine, were found in BMW by a high performance liquid chromatography （HPLC） method, which may explain the hormone-like activity of BMW.展开更多
Abstract： The search for ＂new materials＂ to manufacture building elements for economical housing is the aim of this work. These materials are the following recycled plastics： Low-density polyethylene （LDPE）, rec...Abstract： The search for ＂new materials＂ to manufacture building elements for economical housing is the aim of this work. These materials are the following recycled plastics： Low-density polyethylene （LDPE）, recycled out of discarded soft drink packs： Polyethylene-terephthalate （PET）, recycled out of discarded soft drink bottles; and several plastics, from the printed films used like packages of candies （remainder of production plant by faults in the thickness of the films or in the inked process of themt. These conveniently grounded plastics were taken as ＂arids＂ to be mixed with Normal Portland cement, replacing heavy sand and gravel habitually used in these mixtures. These materials are used in constructive elements such as bricks, blocks and plates for economical houses closures or traditional construction. The developed constructive elements offer high thermal insulation, so they can be used in closures with a smaller thickness than conventional bricks and blocks. Besides, they have a lower specific weight than these traditiunal constructive elements. Recycling means lowering costs, making part of the environment contaminating waste useful and providing the unemployed and/or unqualified work force with jobs through uncomplicated technologies. Therefore, this recycling technology has an economic as well as an ecological purpose.展开更多
基金financial support from the National Natural Science Foundation of China (50974021)Major Project of Chinese National Programs for Fundamental Research and Development (973 Program:2010CB226704)
文摘Recycling gas drilling is a new drilling technology. This paper can be divided into three parts, with the purpose of introducing and analyzing the characteristics of this new technology. First, the major equipment characteristic of this technology was introduced. Secondly, compared with conventional gas drilling, Angel＇s model was used to analyze the wellbore flow characteristics. Due to the closed loop and the effect of back pressure caused by the equipment, the gas flow rate decreases dramatically during drilling. Apart from this, it is also found that the kinetic energy at the casing shoe is always smaller than that at the top of the collar. The proposing of the drilling limit concept points out the basic difference between the two gas drilling technologies. Lastly, according to the results of the theoretical analysis, gas supplement operations for the wellbore must be conducted. Thus, two gas supplement schemes are presented in this paper, to provide some guidance for field operations.
文摘In order to improve the refining effect of zinc ore and promote the development of this industry,taking the hydrometallurgical zinc smelting process as an example,this paper first establishes a model for the recycling of waste residues in the hydrometallurgical process,proposes optimization measures based on proven comprehensive recycling technology for purifying residues to obtain higher valuable metal recovery rate,and provides reference for those in relevant fields.
基金financially supported by the Beijing Natural Science Foundation of China (No. 2232038)the National Natural Science Foundation of China (Nos. 52034002 and U1802253)the Fundamental Research Funds for the Central Universities (No. FRF-TT-19-001)
文摘Copper-indium-gallium-diselenide(CIGS)is a fast-evolving commercial solar cell.The firm demand for global carbon reduction and the rise of potential environmental threats necessitate spent CIGS solar cell recycling.In this paper,the sources and characteristics of valuable metals in spent CIGS solar cells were reviewed.The potential environmental impacts of CIGS,including service life,critical material,and material toxicity,were outlined.The main recovery methods of valuable metals in the various types of spent CIGS,including hydrometallurgy,pyrometallurgy,and comprehensive treatment processes,were compared and discussed.The mechanism of different recovery processes was summarized.The challenges faced by different recycling processes of spent CIGS were also covered in this review.Finally,the economic viability of the recycling process was assessed.The purpose of this review is to provide reasonable suggestions for the sustainable development of CIGS and the harmless disposal of spent CIGS.
基金financially supported by the National Natural Science Foundation of China(No.52074035)the Fundamental Research Funds for the Central Universities(No.00007720)the National Key Research and Development Program of China(No.2020YFC1910000)。
文摘Electric arc furnace dust(EAFD)is a hazardous waste but can also be a potential secondary resource for valuable metals,such as Zn and Fe.Given the increased awareness of carbon emission reduction,energy conservation,and environmental protection,hydrometallurgical technologies for the detoxification and resource use of EAFD have been developing rapidly.This work summarizes the generation mechanisms,compositions,and characteristics of EAFD and presents a critical review of various hydrometallurgical treatment methods for EAFD,e.g.,acid leaching,alkaline leaching,salt leaching,and pretreatment–enhanced leaching methods.Simultaneously,the phase transformation mechanisms of zinc-containing components in acid and alkali solutions and pretreatment processes are expounded.Finally,two novel combined methods,i.e.,oxygen pressure sulfuric acid leaching combined with composite catalyst preparation,and synergistic roasting of EAFD and municipal solid waste incineration fly ash combined with alkaline leaching,are proposed,which can provide future development directions to completely recycling EAFD by recovering valuable metals and using zinc residue.
文摘The aim of this study is to enhance the recycled PVC （polyvinyl chloride） related material property by formulation technology and develop the recycling product processing technology furthermore develop the chemical recycling technology for last stage of PVC wastes. The formulation technology is composed of pre-treatment （crushing, separation etc.） and post-treatment （material ratio, additives, stabilizer etc.） to enhance the recyclate property. The formulation for recycled PVC by application basis and processing technology is applied to produce the structural product for civil and construction application such as pipe fittings and water drainage cap for environmental waterway. Also chemical recycling technology for end life PVC scrap which causes environmental pollution by incineration or landfill is studied for producing hydrocarbon and hydrogen chloride for VCM.
文摘Tanneries reusing wastewater by combination of conventional and advanced Reverse Osmosis (RO) treatment technologies were assessed for technical and economic viabilities. Conventional treatment methods such as neutralization, clari-flocculation and biological processes are followed to clean the effluents before feeding to RO membrane modules. The characteristics of untreated composite effluents such as pH, biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), total dissolved solids (TDS), and total chromium were in the range of 4.00-4.60, 680-3600 mg/L, 1698-7546 mg/L, 980-1480 mg/L, 4200-14500 mg/L, and 26.4-190 mg/L, respectively. Inorganic ions like Ca2+, Na+, Cl– and SO42– were found more in the wastewaters. Conventional treatments significantly removed the organic pollutants however failed to remove dissolved inorganic salts. Membrane technology removed the salts as well as remaining organic pollutants and the product water is reused in the process. The studied tanneries (5 numbers) have achieved 93-98%, 92-99% and 91-96% removal of TDS, sodium and chloride, respectively. Seventy to eighty five percentage of wastewater was recovered and recycled in the industrial processes. The rejects are subject to either solar evaporation system or Multiple Effect Evaporation (MEE) technology. The resulting salts are collected in polythene bags and disposed into scientifically managed secured land fill (SLF) site. The cost of wastewater treatment for operation and maintenances of RO including the pre-treatments (conventional methods) is INR 100-110 m-3.
文摘Water is the basis in ecological residential area. It is very important to recycle the water resource in the designing and planning of the ecological residential quarter due to the critical way to realize the wastewater resource utilization. In this paper, a new technology of wastewater treatment is introduced, which is ORGANICA ecotechnology. We integrate the traditional wastewater treatment technology and modern ecological engineering technology together and apply the integrated technology in the treatment of domestic sewage. The treated water can be reused for landscape and greening, which can beautify the residential area and recycle wastewater.
文摘The present study dealt with relationships between the degradation and humification process that the organic matter underwent during bacteria-mineral technology. An inverse correlation was found between the protein, lipid, and some of the humification indices considered, suggesting that the humification theory is actually humic substances produced from simple-structured natural organic substrates. Weight-average molecular weight （Mw）, number-average molecular weight （Mn）, and the ratio Mw/Mn of dissolved organic matters at different stages of the process were measured by gel permeation chromatography. The results showed that Mn and Mw increased with reaction time from 352 to 17,191, and from 78,707 to 104,564, respectively. The ratio of Mn/Mw decreased from 223.3 to 6.1. This reflected the growth of the polymerization degree of dissolvable organic matters in the process; furthermore, it indicated the formation of complex molecules （humic substances） from more simple molecules. Bacteria-mineral water （BMW） （the effluent of the process） treatments can exert hormone-like activity for enhanced seed germination of wheat and rice and greatly improved chlorophyll synthesis in wheat and rice leaves, Major polyamines （plant regulators） putrescine, spermidine, and spermine, were found in BMW by a high performance liquid chromatography （HPLC） method, which may explain the hormone-like activity of BMW.
文摘Abstract： The search for ＂new materials＂ to manufacture building elements for economical housing is the aim of this work. These materials are the following recycled plastics： Low-density polyethylene （LDPE）, recycled out of discarded soft drink packs： Polyethylene-terephthalate （PET）, recycled out of discarded soft drink bottles; and several plastics, from the printed films used like packages of candies （remainder of production plant by faults in the thickness of the films or in the inked process of themt. These conveniently grounded plastics were taken as ＂arids＂ to be mixed with Normal Portland cement, replacing heavy sand and gravel habitually used in these mixtures. These materials are used in constructive elements such as bricks, blocks and plates for economical houses closures or traditional construction. The developed constructive elements offer high thermal insulation, so they can be used in closures with a smaller thickness than conventional bricks and blocks. Besides, they have a lower specific weight than these traditiunal constructive elements. Recycling means lowering costs, making part of the environment contaminating waste useful and providing the unemployed and/or unqualified work force with jobs through uncomplicated technologies. Therefore, this recycling technology has an economic as well as an ecological purpose.
