固定床气化焦油中固含物性质及对深加工的影响研究

中低温煤焦油的主要来源之一是固定床气化副产焦油,研究固定床气化副产焦油中固含物性质有利于中低温煤焦油的固含物脱除、降低催化剂失活风险,进而降低煤焦油的加工成本。为了高效加工利用煤焦油资源,以新疆固定床气化副产煤焦油中的固含物为研究对象,综合采用基本理化分析、激光粒度分析、金属含量分析、扫描电镜分析、热重分析、傅里叶红外光谱和^(13)C-核磁共振等多种检测技术以解析固含物的组成和结构特征,并探究固含物在固定床气化焦油深加工时对原料预处理、催化剂性能、油收率和产品品质以及固渣处理等方面所产生的影响。研究结果表明,固定床气化副产煤焦油中的固含物具有灰分高以及钙、镁、铝、钾、钠等碱金属和碱土金属含量高、碳含量高的特点,其颗粒粒度分布广泛但颗粒之间的黏连性较差;固含物的官能结构单一,高岭土类矿物质和CH_(2)的特征吸收峰最为显著,碳碳结构的特征吸收峰不明显,其脂肪碳含量较少,而芳香碳又主要以迫位芳香碳结构存在。未来应更专注于气化工艺技术、装备和系统方面的提升研究,从源头上减少和解决焦油的含固问题,进一步促进煤焦油的深加工与焦油原料向集约化、精细化和定制化处理方案设计方向发展。

熔盐氯化生产TiCl_4过程中固含量控制技术研究

针对熔盐氯化各工序中固含量偏高、波动大、控制困难的问题,对氯化工序全流程TiCl_4固含量展开了调研。调查结果表明,淋洗罐内固含量偏高、冷凝工序温度控制偏高造成粗TiCl_4固含量偏高和沉降过程效果不明显。针对调查结果,提出了熔盐氯化炉欠氯反应技术、收尘室和淋洗系统温度控制技术及沉降控制技术等技术措施,有效降低了淋洗罐和粗TiCl_4中的固含量,使淋洗罐内的固含量稳定控制在200 g/L以内,平均值为133. 62 g/L;粗TiCl_4中的固含量控制在15 g/L以下,减小了固含物对氯化系统和成品的影响,为氯化系统的稳定运行提供了保障,为粗TiCl_4精制的产能提高奠定了基础。

畜禽粪便固液分离技术特点及效率评估

该文对常用畜禽粪便固液分离技术进行分析,评估出各分离技术的优缺点、适用对象、分离效果和性价比,为企业选择粪便固液分离设备提供参考。研究结果表明:重力分离技术成本最低,分离粒径小于1 mm的有机物效果最好,但分离后固相含水率过高(>90%),一般作为其他技术的预处理。筛分技术对于分离大粒径的有机颗粒物最有效,投资相对小,运行费用低;但对氮磷等营养元素分离效率较低,分离后的固相的含水率偏高,分离产物可用于固态发酵。压滤技术提高了磷元素的分离效率和固相含水率,但运营成本也增加,分离产物可用于有机肥生产。沉淀离心技术对去除细小颗粒最为有效,并能够去除氮磷元素,但运营成本太高,在中国推广难度大。絮凝剂能和大多数的分离技术结合使用从而提高分离效率。所有固液分离技术都不能分离畜禽粪便中的挥发性脂肪酸,因此也不能有效去除液相中的生化需氧量和臭味。多种分离技术的联合使用,在提高营养物质的分离效率的同时,降低固相的含水率将是未来技术发展的主要方向。

ZrO_2陶瓷膜精制增液复方水提液的膜过程研究

目的:研究ZrO2陶瓷膜澄清增液汤复方水提液的膜过程,进一步优化膜工艺参数。方法:从微滤通量、指标性成分透过率、固含物去除率等角度考察不同孔径的ZrO2膜对微滤过程的影响,同时为了能精确观察指标性成分透过率的动态变化,将实验设为分多次取样。结果:对于增液汤复方水提液,0.2μ ZrO2微滤膜较为适用。其渗透通量衰减较平缓,最终的稳定通量达到172.8L/(m2·h);指标性成分透过率在微滤中期略有波动,但其平均透过率达96.5%;固含物去除率为20%左右。结论:充分掌握中药水提液复杂微滤过程的动态变化规律对提高通量、成分透过率等具有重要意义。

不同材质及孔径的无机陶瓷膜精制黄芪水提液

目的:考察不同材质、不同孔径无机陶瓷膜精制黄芪水提液的适用性,优化工艺参数.方法:为能精确观察指标性成分透过率的动态变化,将实验设为分多次取样.以黄芪水提液为研究对象,从渗透通量、指标性成分透过率、固含物去除率等角度考察膜材质、膜孔径对微滤过程的影响.结果:0.2μm ZrO2较适用于本体系,其稳定渗透通量达273L/(m2.h),黄芪甲苷的透过率达64.56%,固含物的去除率在19%左右.结论:采用无机陶瓷膜对黄芪水提液进行精制分离是可行的,且在适当膜工艺条件下可取得较好精制效果,从而为陶瓷膜分离用于中药精制领域的共性问题提供了依据.

益智安神口服液提取工艺研究

目的:优选益智安神口服液的提取工艺。方法:以栀子苷含量和固含物的综合评分为考察指标,以挥发油提取量为考察因素设计单因素试验,以溶媒量、提取时间、提取次数等3个因素设计L9（34）正交试验优选益智安神口服液提取工艺。结果:最优工艺为益智、郁金、川芎药材加6倍量水,提取4 h,收集挥发油。再将药渣与三七、栀子等药材用10倍药材量的水提取2次,每次2 h。3批样品验证试验的栀子苷提取量平均为3313.90 mg,RSD=2.10%（n=3）,固含物总量平均为73.12 g,RSD=2.36%（n=3）。结论:按照研究的优选工艺参数能够生产出合格的产品,且样品性质稳定,本研究工艺可作为益智安神口服液的制备工艺。

Effect of carbon addition on carbide morphology of single crystal Ni-based superalloy

Single crystal superalloys of AM3 with different carbon levels were prepared at withdraw rate of 50μm/s. The effect of carbon addition on the carbide morphology was investigated. It was found that there were four types of MC-type carbides, acicular, nodular, blocky, and Chinese script-type in the crystals. With an increase in carbon level, the volume fraction of carbide increased significantly while the volume fraction of eutectic decreased significantly. Furthermore, the size of carbide in high level carbon alloy became much larger.

Effects of Peracetic Acid(PAA) Combined with Calcium Treatments on Storage Quality of Loquat Fruit

[Objective] The paper was to evaluate effects of peracetic acid （PAA） combined with calcium treatments on storage quality of Ioquat fruits, so as to pro- vide practical techniques to solve the problems of postharvest rot and quality deteri- oration for Ioquat fruits. [Method] With Ioquat fruits of Qingzhong variety as materi- als, 0.2%, 0.4% and 0.8% PAA combined with 0.8% CaCI2 was used to soak Ioquat fruits for 4 min, 0.8% CaCl2 and water treatments were set as two controls; the fruits were dried and packaged by 0.02 mm PE bags, then stored under non-chilling low temperature of （7±1） ℃. The indicators related to storage quality of Ioquat fruits were randomly tested once every 3 d, and their variation situations were analyzed. [Result] Compared with two control treatments and 0.2% PAA, 0.8% PAA combined with calcium treatments, the treatment of 0.4% PAA combined with 0.8% CaCl2 could significantly inhibit rot index, weight loss rate, firmness and cell membrane permeability of Ioquat fruits during storage period, which could also effectively delay the reduction of titratable acid, vitamin C, soluble solid content and juice yield, and maintain respiration intensity of fruits at a low level; the appearance and flavor qual- ity of fruits were good after stored for 25 d. [Conclusion] 0.4% PAA combined with 0.8% CaCl2 treatment is an efficient, safe and economical practice technology in an- ti-corrosion and quality preservation for postharvest Ioquat fruits .

黄芪注射液超滤工艺优化研究

目的:通过研究,优选黄芪注射液的超滤工艺参数。方法:采用正交试验法,以药液温度、药液浓度、膜孔径和进出口压差为影响因素,对比分析超滤前后药液的黄芪甲苷、毛蕊异黄酮葡萄糖苷含量、固含物、细菌内毒素。结果:药液温度为45~60℃、浓度总固体为60 mg·mL^(-1)、超滤膜孔径为10 k、进出口压力差为0.07 MPa,综合评价得分最高。结论:黄芪注射液选用10 k超滤膜,含量、总固体保留率和细菌内毒素去除率效果较好。

Environmental risk assessment on slag and iron-rich matte produced from reducing-matting smelting of lead-bearing wastes and iron-rich wastes

A new process for utilization of hazardous lead-bearing wastes and iron-rich wastes by reducing-matting smelting has been developed.The slag（SG） and the iron-rich matte（IRM） are the main by-products from reducing-matting smelting of lead-bearing wastes and iron-rich wastes.The environmental risk of heavy metals（Cd,Zn,Pb and As） in the main by-products versus the charging material for reducing-matting smelting（CM） has been systematically assessed using leaching toxicity test,the three-stage sequential extraction procedure of European Community Bureau of Reference（BCR） and Hakanson Potential Ecological Risk Index Method（PERI）.The results demonstrate that the ecological risk level of heavy metals for SG and IRM is significantly reduced after the reducing-matting smelting process compared with that for CM.

Estimation of Biological Nitrogen Fixation Capacity by Sugarcane Using 15N

[ Objective] The study aimed to reveal the biological nitrogen fixation capacity by sugarcane from Brazil under the ecological conditions of Guangxi, and to provide reference for study on the biological nitrogen fixation capacity by sugarcane and related generalization and application. [ Method] The ^15N isotopic fertilizer was solely applied on plants of three sugarcane cultivars planted in greenhouse with no other fertilizer forms applied, meanwhile virus-free stem seedling was regarded as control, to measure their biological nitrogen fixation capacity using ^15N isotope. [ Result ] The nitrogen fixation rate of B8 from Brazil reached 26.91%, while Guitang 11 and RIC16 presented no or poor nitrogen fixation capacity. [ Conclusion] The sugarcane eultivar B8 from Brazil showed some nitrogen fixation capacity under the ecological conditions of Guangxi.

Comparison of Fe^(2+) oxidation by Acidithiobacillus ferrooxidans in rotating-drum and stirred-tank reactors

Fe2＋ oxidation by Acidithiobacillus ferrooxidans（At.ferrooxidans） under different solid contents by adding inert Al2O3 powder was examined in rotating-drum and stirred-tank reactors.The results show that the bioactivity of At.ferrooxidans in the stirred-tank is higher than that in the rotating-drum in the absence of Al2O3 powder,but the biooxidation rate of Fe2＋ decreases markedly from 0.23 g/（L·h） to 0.025 g/（L·h） with increasing the content of Al2O3 powder from 0 to 50%（mass fraction） in the stirred-tank probably due to the deactivation of At.ferrooxidans resulting from the collision and friction of solid particles.The increase in Al2O3 content has a little adverse effect on the bioactivity of At.ferrooxidans in the rotating-drum due to different mixing mechanisms of the two reactors.The biooxidation rate of Fe2＋ in the rotating-drum is higher than that in the stirred-tank at the same content of Al2O3 powder,especially at high solid content.The higher bioactivity of At.ferrooxidans can be maintained for allowing high solid content in the rotating-drum reactor,but its application potential still needs to be verified further by the sulfide bioleaching for the property differences of Al2O3 powder and sulfide minerals.

Transformation of Flue-Gas-Desulfurization Gypsum to α-Hemihydrated Gypsum in Salt Solution at Atmospheric Pressure

Direct phase transformation of flue gas desulfurization gypsum in hot salt solution at atmospheric pres-sure was investigated.The effects of temperature,salt species,salt concentration,solids content,pH and modifier were examined.The crystals obtained under different conditions and solubility of calcium sulfate in contact with solid gypsum were also determined.α-Calcium sulfate hemihydrate crystals of stubby columnar shape and regular pentahedral sides were obtained under the following conditions：salt concentration 20%-30%,operation tempera-ture 95-100 °C,solids mass content in the slurry 10%-30% and neutral pH.Thermodynamic analysis revealed that phase transformation of calcium sulfate dihydrate to α-calcium sulfate hemihydrate occurs because of the difference in solubilities between the two solid gypsum phases in this system.

Catalytic effect of silver-bearing solid waste on chalcopyrite bioleaching:A kinetic study

Silver ion can be useful in improving chalcopyrite bioleaching efficiency.In this work,leaching kinetics of this process was investigated using silver-bearing solid waste under different chalcopyrite/solid waste ratios.Bioleaching behavior indicates that silver-bearing solid waste can enhance the bioleaching process,and the redox potential is much higher than the proposed appropriate range(380−480 mV vs Ag/AgCl)with the solid waste added.There is a positive correlation between temperature and copper extraction rate.The kinetics data fit well with the shrinking-core model.Under these leaching conditions,the bioleaching of chalcopyrite is controlled by internal diffusion with calculated apparent activation energy(Ea)of 28.24 kJ/mol.This work is possible benificial to promote the industrial application of silver catalyst in leaching of chalcopyrite.

Effect of Si content on interfacial reaction and properties between solid steel and liquid aluminum

The effect of Si content on the microstructures and growth kinetics of intermetallic compounds(IMCs)formed during the initial interfacial reaction(<10 s)between solid steel and liquid aluminum was investigated by a thermophysical simulation method.The influence of Si addition on interfacial mechanical properties was revealed by a high-frequency induction brazing.The results showed that IMCs layers mainly consisted ofη-Fe_(2)Al_(5)andθ-Fe_(4)Al_(13).The addition of Si reduced the thickness of the IMCs layer.The growth of theηphase was governed by the diffusion process when adding 2 wt.%Si to the aluminum melt.When 5 wt.%or 8 wt.%Si was added to aluminum,the growth was governed by both the diffusion process and interfacial reaction,and ternary phaseτ1/τ9-(Al,Si)_(5)Fe_(3)was formed in theηphase.The apparent activation energies of theηphase decreased gradually with increasing Si content.The joint with pure aluminum metal had the highest tensile strength and impact energy.

Effects of High CO_2 Pretreatment on the Quality of Fresh-Cut Potatoes

Effects of short-term high CO_2 pretreatment on quality of fresh-cut potatoes were studied. Potatoes were treated under 90% CO_2 for 18 h, peeled, cut, dipped in 1% ascorbic acid or distilled water for 3 min, packed in polyethylene bags and stored for 12 d at 4 ℃. Non-treated potatoes were used as the control. High CO2 pretreatments ensured maintenance of a high level of CO_2 in headspace of packages containing fresh-cut potatoes. Both the growth of total aerobic bacteria in initial stages of post-cut storage and browning index of the cut surface were lower in high CO_2 treated cut potato. Anti-browning effect of high CO_2 pretreatment was decreased when applied in combination with ascorbic acid. Soluble solids, pH, titratable acidity and flesh firmness of fresh-cut potatoes were not affected by high CO_2 treatment. Therefore, high CO_2 treatment before slicing could be effective method to maintain quality of flesh-cut potatoes.

Eutectic effect during mesophase formation in co-carbonization of ethylene tar pitch and polystyrene

Ethylene tar pitch was co-carbonized with waste polystyrene to prepare mesophase pitch. The character- istics of mesophase pitches were examined using polarized light optical microscopy, apparent viscome- try, Fourier transform infrared spectrometry, IH nuclear magnetic resonance spectrometry, and X-ray diffractometry. The properties of the mesophase pitch were greatly improved because of the eutectic effect. The soluble content increased from 5% to 56%, the mesophase itself increased from 32% to 100%, and the optical texture was changed from a coarse mosaic into a flow domain after the waste polystyrene was added to the ethylene tar pitch. The apparent viscosity showed that the mesophase pitch changed from thixotropic to Newtonian suggesting improved rheological behavior during co-carbonization）The increased number of alkyl groups, which are mainly methylene groups, altered the molecular structure of the mesophase pitch in a way that resulted in the eutectic effect.

Influence of Atomization Parameters in the Obtention of Mango Pulp Powder

Mango is a widely cultivated and consumed fruit in Brazil and one of the most important alternatives to take advantage of the production excess is dehydration. Therefore, this work aims at establishing better operational conditions for ＂spray-drying＂ processes, in order to obtain the powder of mango pulp by means of a rotational central compounded planning, and also at carrying out the physicochemical characterization of both the integral mango pulp and the powder obtained from the operational conditions mentioned above. Both integral mango pulp and powder were analyzed as for the following physicochemical characteristics： humidity, pH, titratable acidity, soluble solids （~Brix）, vitamin C and color--through parameters L＊, a＊, b＊ and h0, Chrome （C＊） and color difference （AEL＊a＊b＊）. The experimental planning used presented significant differences at 5% of probability, showing that the model was adjusted to the data in accordance to F test, thus being possible to determine the best process conditions. In addition, the average results of the physicochemical parameters pointed out that the pulp used was in accordance with the patterns established by the quality and identity patterns for mango pulp. Moreover, it showed that the powder obtained had good physicochemical quality.

Effect of Different Shading Practices Used at Pre-harvest Stage on Quality and Storage Life of Sultana Seedless Grapes

Covering the grapevine rows to delay maturity and thus the harvest date becomes a widespread practice at Sultana seedless vineyards. The research work was carried out with different covers to examine their effects on grape quality and storage life in 2009 and 2010. Grapevines were covered with three different densities （shading ratios： 35%, 55%, 75%） at the veraison period. Unshaded （0%） control grapevines and grapevines shaded under different ratios were covered with polypropylene cross-stitch just before harvest maturity. Grapes under cover were harvested nearly one month after than those maturing under open conditions. Grape clusters were packed in PE bags and pre-cooled after harvest and then SO2-generating pads has been put on top, bags were sealed. In the second year at the 120th day of the storage, decay development has been observed in all applications. Total soluble solids content, maturity index and a＊ colour value were found lower in 55% and 75% shaded grapes compared to unshaded grapevines. Still, berry removal force and hue angle value in 55% and 75% of shaded grapes were higher than unshaded grapes. Effects of shading ratios on these parameters decrease or disappear at the end of storage.

Studies on the Compositional Properties of Main Miben Series Pumpkin Varieties in Southern China

Pumpkin is among the most popular agricultural products in Southern China. To determine the important analytical properties(dry matter, total soluble sugar,dissolvable polysaccharides, mineral content, electricity conductivity, soluble solid content, fruit weight, fat, protein, fiber, pectin, β-carotene and edible rate) of pumpkin in Southern China, this study investigated the physical and chemical properties and texture of raw and steamed pumpkins of 13 Miben series varieties. Miben pumpkins were frozen at-40 ℃ for 24 h, or at-4 ℃ for 24 h, or were steamed for 15 min in boiling water to investigate the effect of different treatments on the textural change, and to reveal the texture and sensory properties of the different varieties. A total of 13 pumpkin varieties of Miben series CP1578, CP2116, XM2-2,Baimi II, Guangmi I, Guangzhouluxia, Jintong, Laojinhanzaoshu, Quanguanjixiang,Newzuhe III, V pumpkin, Zaoshutianmi and Daguomiben were involved in this study.The results showed that the Miben series pumpkins had significant difference in physical properties. The editable rate of Miben series pumpkins was higher than77%. Chemical properties varied among different varieties. Textures of pumpkin flesh after different processes were different. In the sensory assessment of Miben pumpkins, the varieties with overall quality scores more than 50 were Guangmi I, Laojinhanzaoshu, V pumpkin and Daguomiben, indicating that the four varieties all had excellent properties.