Interests in charcoal usage have recently been re-ignited because it is believed that charcoal is a muchbetter fuel than wood. The conventional charcoal production consumes a large amount of energy due to the prolonge...Interests in charcoal usage have recently been re-ignited because it is believed that charcoal is a muchbetter fuel than wood. The conventional charcoal production consumes a large amount of energy due to the prolonged heating time and cooling time which contribute to the process completing in one to several days. Wood py-rolysis consists of both endothermic and exothermic reactions as well as the decomposition of the different components at different temperature range （hemicellulose： 200-260℃; cellulose： 240-350℃ and lignin： 280-500℃）. Inthis study we propose a multistagepyrolysis which is an approach to carry out pyrolysis with multiple heating stages so as to gain certain processing benefits. We propose a three-stage approach which includes rapid stepwise heating stage to a variable target temperatures of 250 ℃, 300℃, 350 ℃ and 400 ℃, slow and gradual heatingstage to a tinal temperature of 400℃ and adiabatic with cooling stage. The multi-stage pyrolysis process can save 30% energy and the processing time by using a first temperature target of 300 ℃and heating rate of 5℃.min-1 to produce a fixed-carbon yield of 25.73% as opposed to the base case with a fixed-carbon yield of23.18%.展开更多
The authors investigated the plant species used for charcoal production and their sources and the willingness of the producers to plant charcoal-making species. Furthermore, the authors indirectly determined the invol...The authors investigated the plant species used for charcoal production and their sources and the willingness of the producers to plant charcoal-making species. Furthermore, the authors indirectly determined the involvement of farmers in charcoal production in Atwima Mponua District of Ghana. A total of 120 producers were interviewed and simple ranking was used for the analysis. Twenty-three plant species were used with the first, second, third and fourth which were Celtis mildbraediL Cylicodiscus gabunensis, Margaritoria discoides and Amphimas pterocarpoides respectively. However, the Amphimas pterocarpoides was not among the traditional charcoal-producing species. The wood used came from seven different sources. None of the charcoal producers had a plantation of charcoal-producing species. Only 13 % of the producers were willing to plant, 87% of them who were not willing to plant indicated that they would leave charcoal production if the resource got finished. The 120 charcoal producers were made up roughly of 56% males, and 44% females and in which 69.2% of them were farmers.展开更多
Blacksmiths in Nepal are marginalized and disadvantaged occupational caste, however, very popular for their handicraft works mainly in making iron tools and equipments. With the advancement of technology, there have b...Blacksmiths in Nepal are marginalized and disadvantaged occupational caste, however, very popular for their handicraft works mainly in making iron tools and equipments. With the advancement of technology, there have been many innovative technologies in many other sectors, but blacksmiths in Nepal are still dependent on their indigenous and conventional practices which have direct negative consequences for environment, biodiversity conservation and health. Recently, improved charcoal production technology has been implemented among the 77 blacksmith households in Sindhupalchowk district as a pilot project. However, there is little research about the impact of improved charcoal production on forest resources conservation and people＇s livelihoods. This study therefore made an effort to explore the impact of improved charcoal production technology and firewood consumption on conserving the environment and promoting sustainable livelihood of marginalized households in rural areas of Nepal. Findings of the study revealed that improved charcoal production technology has positive impacts on forest tree conservation by reducing the fuel wood consumption up to 40% with 60% energy efficiency as compared to the traditional system. The improved charcoal production pilot project has reduced annual CO2, CH4 and CO emissions in the study area by 2.4-3.1, 3.3-4.3 and 2.6-3.5 tons, respectively. Furthermore, improved charcoal production system increases blacksmiths＇ welfare through generating social, human and economic capital and quality attributes like environmental sustainability. Introducing improved charcoal production and controlling heavy firewood collection at rural villages of Nepal will help to increase carbon sequestration and reduce the sources of carbon emission in context of global climate change.展开更多
基金Supported by the Hong Kong RGC in form of PhD Fellowship to Adetoyese Olajire Oyedun(PF09-05997)
文摘Interests in charcoal usage have recently been re-ignited because it is believed that charcoal is a muchbetter fuel than wood. The conventional charcoal production consumes a large amount of energy due to the prolonged heating time and cooling time which contribute to the process completing in one to several days. Wood py-rolysis consists of both endothermic and exothermic reactions as well as the decomposition of the different components at different temperature range （hemicellulose： 200-260℃; cellulose： 240-350℃ and lignin： 280-500℃）. Inthis study we propose a multistagepyrolysis which is an approach to carry out pyrolysis with multiple heating stages so as to gain certain processing benefits. We propose a three-stage approach which includes rapid stepwise heating stage to a variable target temperatures of 250 ℃, 300℃, 350 ℃ and 400 ℃, slow and gradual heatingstage to a tinal temperature of 400℃ and adiabatic with cooling stage. The multi-stage pyrolysis process can save 30% energy and the processing time by using a first temperature target of 300 ℃and heating rate of 5℃.min-1 to produce a fixed-carbon yield of 25.73% as opposed to the base case with a fixed-carbon yield of23.18%.
文摘The authors investigated the plant species used for charcoal production and their sources and the willingness of the producers to plant charcoal-making species. Furthermore, the authors indirectly determined the involvement of farmers in charcoal production in Atwima Mponua District of Ghana. A total of 120 producers were interviewed and simple ranking was used for the analysis. Twenty-three plant species were used with the first, second, third and fourth which were Celtis mildbraediL Cylicodiscus gabunensis, Margaritoria discoides and Amphimas pterocarpoides respectively. However, the Amphimas pterocarpoides was not among the traditional charcoal-producing species. The wood used came from seven different sources. None of the charcoal producers had a plantation of charcoal-producing species. Only 13 % of the producers were willing to plant, 87% of them who were not willing to plant indicated that they would leave charcoal production if the resource got finished. The 120 charcoal producers were made up roughly of 56% males, and 44% females and in which 69.2% of them were farmers.
文摘Blacksmiths in Nepal are marginalized and disadvantaged occupational caste, however, very popular for their handicraft works mainly in making iron tools and equipments. With the advancement of technology, there have been many innovative technologies in many other sectors, but blacksmiths in Nepal are still dependent on their indigenous and conventional practices which have direct negative consequences for environment, biodiversity conservation and health. Recently, improved charcoal production technology has been implemented among the 77 blacksmith households in Sindhupalchowk district as a pilot project. However, there is little research about the impact of improved charcoal production on forest resources conservation and people＇s livelihoods. This study therefore made an effort to explore the impact of improved charcoal production technology and firewood consumption on conserving the environment and promoting sustainable livelihood of marginalized households in rural areas of Nepal. Findings of the study revealed that improved charcoal production technology has positive impacts on forest tree conservation by reducing the fuel wood consumption up to 40% with 60% energy efficiency as compared to the traditional system. The improved charcoal production pilot project has reduced annual CO2, CH4 and CO emissions in the study area by 2.4-3.1, 3.3-4.3 and 2.6-3.5 tons, respectively. Furthermore, improved charcoal production system increases blacksmiths＇ welfare through generating social, human and economic capital and quality attributes like environmental sustainability. Introducing improved charcoal production and controlling heavy firewood collection at rural villages of Nepal will help to increase carbon sequestration and reduce the sources of carbon emission in context of global climate change.
