在线激光乙炔分析仪在醋酸乙烯合成中的应用

本文介绍了以乙炔和醋酸为原料生产醋酸乙烯合成工艺中进行乙炔在线分析的重要性和传统检测方法的不足。在基于TDLAS技术基本原理的基础上,阐述了激光分析仪的性能特点和系统结构,以及在醋酸乙烯合成装置中乙炔在线检测应用中的优势。实际的应用结果表明,基于TDLAS技术的激光在线气体分析仪可以满足醋酸乙烯合成装置中乙炔浓度检测的应用要求。     

多宝山铜矿石高压电脉冲破碎预处理试验研究

通过对比高压电脉冲破碎和机械破碎对多宝山铜矿石性质和浮选指标的影响,探索了高压电脉冲破碎预处理对矿石的促进解离、预弱化和预富集等作用效果。采用自制高压电脉冲处理系统在140 kV下对26.5~31.5 mm粒级多宝山铜矿石进行了预处理,并与同条件下的机械破碎产品对比。分别测定了高压电脉冲破碎产品和机械破碎对比样品的硬度指标A×b值、邦德球磨功指数、Cu品位分布、单体解离度和可浮性。结果表明,相比机械破碎产品,高压电脉冲破碎产品的硬度指标A×b值提高了33.9%~39.8%,邦德球磨功指数降低了3.6 kWh/t;高压电脉冲破碎产品的Cu品位随粒度减小而快速增大,能够将69.2%的Cu元素预富集到产率为36.1%的-13.2 mm粒级破碎产品中;通过促进矿物单体解离,高压电脉冲破碎能够将Cu的浮选回收率提高2.33个百分点,精矿铜品位提高约1个百分点。试验结果可以为低品位铜矿石的高效低耗回收提供参考。     

生态匀染机节能减排染色工艺技术开发

传统涤棉混纺织物染整工艺耗水量大、污染严重。文中结合工厂使用的生态匀染机,介绍了涤棉针织物生物酶前处理、抛光、染色一浴工艺、染色后处理高效皂洗工艺、省水水洗工艺等几种节能减排工艺,并与传统工艺进行对比分析。结果表明,新工艺弥补了低浴比染机存在的局限性、降低了水、电、汽等能源消耗,提高了生产效率,产业化经济效益明显。     

金属型铸造铸态铁素体球墨铸铁的试验研究

介绍金属型获得铸态铁素体球铁的工艺及其铸态组织与性能 ;实验发现 ,采用铝和石墨对铁液进行预处理、含铋孕育剂的瞬时孕育 ,对增加石墨球数和防止表面白口的形成作用十分显著。铸态组织中铁素体含量大于 98%,石墨球细小、圆整 ,平均直径12 μm,单位面积的球数 90 0个 /mm2 以上 ,球化率达 90 %以上。铸态机械性能达到QT45 0 15。     

消除20钢无缝管冷弯成型角裂的预处理工艺试验

对两批20钢无缝矩形管冷弯成型时角部出现裂纹的现象进行了组织观察分析,认为原料管热轧工艺不当而形成的魏氏组织是裂纹形成的主要原因。提出了冷弯成型前对原料管进行预处理的工艺方案;研究分析了正火温度、保温时间和冷却方式对原料管组织和力学性能的影响规律;确定了20钢原料管的常规正火工艺:加热温度(890±10)℃,保温6min后散置空冷。本常规正火工艺可完全消除20钢原料管的魏氏组织,使其屈服强度和抗拉强度的匹配更加合理,屈强比σS/bσ≤0.78,延伸率5δ≥30%,冷成型性能大幅度提高并避免出现冷弯开裂现象。     

Production of bio-ethanol from an innovative mixture of surgical waste cotton and waste card board after ammonia pre-treatment

Ethanol production from waste biomass using a slightly modified bio-refinery approach was performed in this work to cater to the increasing need of alternate fuels and fuel additives globally. A surgical waste cotton and waste packaging cardboard mixture after a 15% v/v ammonia pre-treatment showed 70% lignin removal. An optimized saccharification using In-house Cellulases produced from Trichoderma harzanium ATCC 20846 had a percentage saccharification of 45% and percentage yield saccharification of 94.6%. An optimized fermentation using Saccharomyces cereviseae strain RW143 resulted in the yield of 0.4 g ethanol/g glucose from the 15% (v/v) glucose in the enzymatically saccharified hydrolysate loaded. The distilled ethanol had 90% (v/v) concentration and180 proof (twice the amount of concentration percentage in v/v) purity. 1 kg biomass mixture when processed as mentioned would yield 120 mL ethanol. Two diesel-ethanol blends (E-10 and E-20) and a commercial Diesel control were used to rate an IC engine’s brake power.     

Viability of ultrasonication of food waste for hydrogen production

Batch anaerobic studies were conducted to study the effect of ultrasonication as a pre-treatment method for pulp waste prior to anaerobic hydrogen production. Pre-treatment was conducted by sonicating a 100 mL of pulp waste at different sonication times varying from 0.5 min to 30 min. The ultimate hydrogen production increased with increasing sonication time. The highest ultimate hydrogen production was achieved at a sonication time of 30 min and reflected an 88% increase over the unsonicated food waste, of 80 mL/g VS_added. The highest final VFAs concentration after fermentation (corresponding to 70% increase over the unsonicated food waste) was also achieved at a sonication time of 30 min. There were no significant differences between the acetate-to-butyrate ratios (HAc/HBu) for the all sonication times. The maximum hydrogen production rate at sonication time of 30 min was about 145% higher than that the unsonicated food waste.     

Effect of pre-treatment and biofouling of proton exchange membrane on microbial fuel cell performance

Nafion^® 117, as the most popular proton exchange membrane, has been studied with regards to the effect of pre-treatment and biofouling for bioelectricity production and wastewater treatment, in dual chamber microbial fuel cells. The obtained results showed that maximum generated power was obtained using pre-treated Nafion^® 117, at approximately 100 mW/m². However, maximum generated power for untreated Nafion^® 117 and biofouled Nafion^® 117 were 52.8 mW/m² and 20.9 mW/m², respectively. Furthermore, the columbic efficiency of pre-treated Nafion^® 117 was 2.32 and 4.15 times higher than untreated and biofouled Nafion^® 117, respectively. Obtained results demonstrated that the pre-treatment of the proton exchange membrane is necessary to reach higher powers, and biofouling is a major obstacle for proton exchange membranes in dual chamber MFCs.     

Pre-treatment study on two-stage biohydrogen and biomethane productions in a continuous co-digestion process from a mixture of swine manure and pineapple waste

This study involves continuous co-digestion of swine manure and pineapple waste mixture using two-stage anaerobic reactors and examines hydraulic retention time (HRT) and substrate heat pre-treatment. The maximum hydrogen and methane production rates of 1488.62 and 991.57 mL/L/d, respectively, reached optimal HRTs of 4.5 h in the hydrogen production fermenter (HPF) and 9 d in the methane production fermenter (MPF) using heat pre-treatment. Acetic acid is a dominant volatile fatty acid of the soluble metabolites with values 70%–73% under all the tested conditions and increased values under heat pre-treatment and high HRT. Firmicutes and Euryarchaeota are the main bacteria species detected in HPF and MPF, respectively. The optimal total energy of 196.47 kJ/L/d and chemical oxygen demand (COD) removal efficiency of 90% were obtained by a complete anaerobic co-digestion process at a high substrate concentration of 105 g COD/L and low HRT of 4.5 h. This shows that the two-stage co-digestion process could increase the COD removal efficiency, hydrogen production rate, and net energy gains and produce high quality biogas and significantly reduce fermentation time.