Natural zeolite particles of 40, 80 and I00 phr were incorporated into natural rubber (NR) using a two-roll mill. The surface treatment of zeolite particles was expected to improve their cure characteristics and the...Natural zeolite particles of 40, 80 and I00 phr were incorporated into natural rubber (NR) using a two-roll mill. The surface treatment of zeolite particles was expected to improve their cure characteristics and their tensile properties. Two types of silane coupling agents, i.e., bis-[3-(triethoxysilyl)-propyl]-tetrasulfide (Coupling 89) and 3-Octanoylthio-l-propyltriethoxysilane (NXT) at various loadings of 2, 4 and 8 percent by weight (%wt) were selected. The viscosity and cure time of the rubber compound increased, while the scorch time decreased after the treatment of zeolite by both coupling agents. The viscosity of the rubber compound predominantly increased when increasing Coupling 89, however, NXT loadings showed no significant effect on the cure characteristics Moreover, the amount and type of coupling agent influenced the tensile properties of the vulcanizates, as a result of the increase in tensile strength, and tensile modulus with increasing both coupling agents loading. The tensile properties of the vulcanizates increased at low Coupling 89 concentrations (2-4%wt), but decreased at high Coupling 89 loading (8%wt). Since NXT has a less bulky structure and lower viscosity compared with Coupling 89, it thus reacts with the silanol groups on the zeolite surface more readily, resulting in the decrease in filler-filler interaction, leading to better tensile properties.展开更多
Since the introduction of"green tyres" in the early 90's, the use of silica as a reinforcing filler, along with a silane coupling agent, has spread and grown worldwide. The greatest advantage of using silica over c...Since the introduction of"green tyres" in the early 90's, the use of silica as a reinforcing filler, along with a silane coupling agent, has spread and grown worldwide. The greatest advantage of using silica over carbon black as reinforcing filler in a tyre tread compound is that a lower rolling resistance is achieved, while maintaining good wet traction. However, a previous study has shown that the wear resistance of a silica filled ENR (epoxidised natural rubber) compound was not as high as those of conventional OESBR (oil extended styrene butadiene rubber) and NR/BR compounds used in passenger car and truck tyre treads. In this work, with the aim of improving abrasion resistance, the effect of blending BR (butadiene rubber) into a silica filled ENR compound was studied. Blends with 0 to 30 phr BR were prepared in a Polylab Haake internal mixer. The rheological properties of the compounds were measured using a Mooney viscometer and oscillating-disc rheometer. The hardness, tensile strength and DIN abrasion resistance were also measured. The results showed that the ENR/silica compound properties such as tensile strength and hardness were as good as those of the conventional compounds. However, the most important finding was that abrasion resistance increased significantly with BR content, exceeding that of the conventional compound at BR: ENR ratios of greater than 20:80.展开更多
The recovery or capture of one or more components from gas mixture by membrane separation has become a research focus in recent years.This study investigates the gas-membrane solution equilibrium,for which Henry's...The recovery or capture of one or more components from gas mixture by membrane separation has become a research focus in recent years.This study investigates the gas-membrane solution equilibrium,for which Henry's law is not applicable if the gas phase is a mixture.This problem can be solved by using UNIQUAC model to calculate the activity coefficient of gas dissolved in the membrane.A method was proposed in this study to obtain the gas-membrane interaction parameter for UNIQUAC model.By the experiments of gas permeation through polydimethylsiloxane PDMS membrane,the solubility coefficients of some gases(N2,CO2,CH4) were measured.Through non-linear fitting UNIQUAC model to the experimental results from this study and in literature(H2,O2,C3H8),the gas-membrane interaction parameters for these gases were obtained.Based on these parameters,the activity coefficients of the dissolved gas were calculated by UNIQUAC model,and their values agree well with the experimental data.These results confirm the feasibility and effectiveness of the proposed method,which makes it possible to better predict gas-membrane solution equilibrium.展开更多
Helsinki Environmental Services Authority HSY ,Ammaissuo waste management centre consists of two landfill sites. The old land filling area was established in 1987 and closed in 2007. The landfilling at the new landfil...Helsinki Environmental Services Authority HSY ,Ammaissuo waste management centre consists of two landfill sites. The old land filling area was established in 1987 and closed in 2007. The landfilling at the new landfill section started in November 2007. Until spring 2014 the main treatment method for source separated MSW (municipal solid'waste) collected from Helsinki Metropolitan area households was landfilling. Approximately 250,000 tonnes of MSW was landfilled annually. From April 2014 on all of the MWS has been utilized in heat and electricity production at new Waste to Energy plant owned and operated by energy company Vantaa Energy Ltd. The landscaping of the landfills is currently ongoing. The construction of the landfill gas collection system was started in 1994 and from 1996 on landfill gas from old landfill area was recovered and burned in torches to reduce the greenhouse gas effect caused by methane in landfill gas. In the end of year (2004) new landfill gas utilisation system was taken in use Gas was used as a fuel in HOB (heat only boiler) to generate district heating for nearby community as well as commercial and industrial sites. The capacity of the system was 7,000 Nm3/h that corresponded to app. 30 MW of heat. Since district heat was mainly needed only during the cold season of the year only about half of the landfill gas produced by the landfill was able to utilize and rest of the gas was still flared leading to relatively low utilization rate of the gas. The construction work of the new 15 MW + 1.2 MW electricity power plant started in spring 2009. The power plant consists of four gas engines and generators and organic rankine cycle process utilizing thermal oil for heat transfer from exhaust gas and steam turbine with hexamethyldisiloxane (silicone oil) as a medium agent. The ORC (Organic Rankine Cycle)-process was commissioned in August 2011 and the operational experiences have been very good. Based on current knowledge the HSY power plant is the biggest landfill gas fired power plant in Europe and probably even in the whole world. Also the combined engine and ORC-process is unique for landfill gas power plants. The third phase of the biogas utilization took place in summer 2015 when the anaerobic digestion biowaste treatment plant was introduced. At the moment the product gas from digestion plant is utilized at landfill gas power plant. In the future gas will be used as a fuel for new power plant process consisting two gas engines and ORC process. Commissioning of the new power plant will take place in October 2016. This paper presents detailed description of the landfill gas utilization system of HSY waste treatment centre and information on operational experiences of landfill gas fired power plant process.展开更多
文摘Natural zeolite particles of 40, 80 and I00 phr were incorporated into natural rubber (NR) using a two-roll mill. The surface treatment of zeolite particles was expected to improve their cure characteristics and their tensile properties. Two types of silane coupling agents, i.e., bis-[3-(triethoxysilyl)-propyl]-tetrasulfide (Coupling 89) and 3-Octanoylthio-l-propyltriethoxysilane (NXT) at various loadings of 2, 4 and 8 percent by weight (%wt) were selected. The viscosity and cure time of the rubber compound increased, while the scorch time decreased after the treatment of zeolite by both coupling agents. The viscosity of the rubber compound predominantly increased when increasing Coupling 89, however, NXT loadings showed no significant effect on the cure characteristics Moreover, the amount and type of coupling agent influenced the tensile properties of the vulcanizates, as a result of the increase in tensile strength, and tensile modulus with increasing both coupling agents loading. The tensile properties of the vulcanizates increased at low Coupling 89 concentrations (2-4%wt), but decreased at high Coupling 89 loading (8%wt). Since NXT has a less bulky structure and lower viscosity compared with Coupling 89, it thus reacts with the silanol groups on the zeolite surface more readily, resulting in the decrease in filler-filler interaction, leading to better tensile properties.
文摘Since the introduction of"green tyres" in the early 90's, the use of silica as a reinforcing filler, along with a silane coupling agent, has spread and grown worldwide. The greatest advantage of using silica over carbon black as reinforcing filler in a tyre tread compound is that a lower rolling resistance is achieved, while maintaining good wet traction. However, a previous study has shown that the wear resistance of a silica filled ENR (epoxidised natural rubber) compound was not as high as those of conventional OESBR (oil extended styrene butadiene rubber) and NR/BR compounds used in passenger car and truck tyre treads. In this work, with the aim of improving abrasion resistance, the effect of blending BR (butadiene rubber) into a silica filled ENR compound was studied. Blends with 0 to 30 phr BR were prepared in a Polylab Haake internal mixer. The rheological properties of the compounds were measured using a Mooney viscometer and oscillating-disc rheometer. The hardness, tensile strength and DIN abrasion resistance were also measured. The results showed that the ENR/silica compound properties such as tensile strength and hardness were as good as those of the conventional compounds. However, the most important finding was that abrasion resistance increased significantly with BR content, exceeding that of the conventional compound at BR: ENR ratios of greater than 20:80.
文摘The recovery or capture of one or more components from gas mixture by membrane separation has become a research focus in recent years.This study investigates the gas-membrane solution equilibrium,for which Henry's law is not applicable if the gas phase is a mixture.This problem can be solved by using UNIQUAC model to calculate the activity coefficient of gas dissolved in the membrane.A method was proposed in this study to obtain the gas-membrane interaction parameter for UNIQUAC model.By the experiments of gas permeation through polydimethylsiloxane PDMS membrane,the solubility coefficients of some gases(N2,CO2,CH4) were measured.Through non-linear fitting UNIQUAC model to the experimental results from this study and in literature(H2,O2,C3H8),the gas-membrane interaction parameters for these gases were obtained.Based on these parameters,the activity coefficients of the dissolved gas were calculated by UNIQUAC model,and their values agree well with the experimental data.These results confirm the feasibility and effectiveness of the proposed method,which makes it possible to better predict gas-membrane solution equilibrium.
文摘Helsinki Environmental Services Authority HSY ,Ammaissuo waste management centre consists of two landfill sites. The old land filling area was established in 1987 and closed in 2007. The landfilling at the new landfill section started in November 2007. Until spring 2014 the main treatment method for source separated MSW (municipal solid'waste) collected from Helsinki Metropolitan area households was landfilling. Approximately 250,000 tonnes of MSW was landfilled annually. From April 2014 on all of the MWS has been utilized in heat and electricity production at new Waste to Energy plant owned and operated by energy company Vantaa Energy Ltd. The landscaping of the landfills is currently ongoing. The construction of the landfill gas collection system was started in 1994 and from 1996 on landfill gas from old landfill area was recovered and burned in torches to reduce the greenhouse gas effect caused by methane in landfill gas. In the end of year (2004) new landfill gas utilisation system was taken in use Gas was used as a fuel in HOB (heat only boiler) to generate district heating for nearby community as well as commercial and industrial sites. The capacity of the system was 7,000 Nm3/h that corresponded to app. 30 MW of heat. Since district heat was mainly needed only during the cold season of the year only about half of the landfill gas produced by the landfill was able to utilize and rest of the gas was still flared leading to relatively low utilization rate of the gas. The construction work of the new 15 MW + 1.2 MW electricity power plant started in spring 2009. The power plant consists of four gas engines and generators and organic rankine cycle process utilizing thermal oil for heat transfer from exhaust gas and steam turbine with hexamethyldisiloxane (silicone oil) as a medium agent. The ORC (Organic Rankine Cycle)-process was commissioned in August 2011 and the operational experiences have been very good. Based on current knowledge the HSY power plant is the biggest landfill gas fired power plant in Europe and probably even in the whole world. Also the combined engine and ORC-process is unique for landfill gas power plants. The third phase of the biogas utilization took place in summer 2015 when the anaerobic digestion biowaste treatment plant was introduced. At the moment the product gas from digestion plant is utilized at landfill gas power plant. In the future gas will be used as a fuel for new power plant process consisting two gas engines and ORC process. Commissioning of the new power plant will take place in October 2016. This paper presents detailed description of the landfill gas utilization system of HSY waste treatment centre and information on operational experiences of landfill gas fired power plant process.