Preparation of Cationic Starch by Electromagnetic Dry Process (EMDP)

Introduction Cationic starches are a series of products of which various sorts with different properties and usages can all be produced via cationic reactions by using different types of etherification agents under different conditions. As an additive and strengthening agent,

Energy and Cost Analysis of Cement Production Using the Wet and Dry Processes in Nigeria

The study evaluates the energy consumption of both wet and dry processes cement manufacturing plant in Nigeria. Enrgy consumption data collected for the period 2003 to 2011 were used to estimate the energy consumption of the crushing, milling, agitation, burning, grinding and bagging operations. The total energy evaluation was based on the three primary energy sources which include electrical, combustion and human. The total estimated energy intensities were 6545 MJ/ton and 4197 MJ/ton for wet and dry processes respectively. The percentage consumption of energy in each operation is 93.68 and 90.34% (burning), 2.11 and 4.33% (milling), 0.43 and 0.67% (crushing), 1.39 and 0% (agitation), 2.12 and 3.90% (grinding), and 0.27 and 0.75% (bagging) of the total energy inputs for the wet and dry processes respectively. Furthermore, the average total energy cost of production showed that wet process is approximately 40% more cost intensive in cement production than the dry process while at the same time it is cost effective to run production on energy through gas powered plant than the national grid.

Simulation of Wetting and Drying Processes in A Depth Integrated Shallow Water Flow Model by Slot Method

A particular porosity method named ＂slot method＂ is implemented in a depth-integrated shallow water flow model （DIVAST） to simulate wetting and drying processes. Discussed is the relationship between the shape factors of the ＂slot＂ and the preset depth used in ＂wetting-drying＂ algorithm. Two typical tests are conducted to examine the performance of the method with the effect of the shape factors of the ＂slot＂ being checked in detail in the first test. Numerical results demonstrate that： 1 ） no additional effort to improve the finite difference scheme is needed to implement ＂slot method＂ in DIVAST, and 2） ＂slot method＂ will simulate wetting and diying processes correctly if the shape factors of the ＂slot＂ being selected properly.

Bacterial Cellulose-Silver Antibacterial Composites：Effects of Drying Processes of Bacterial Cellulose

A type of antibacterial bacterial cellulose(BC) film was prepared for potential uses as wound dressing.In order to obtain a high antibacterial effect,some forms of BC films,including the wet and dried ones were utilized as the template to in situ synthesize silver nanoparticles(AgNPs).The effects of drying methods including freeze-drying,heat drying and air drying,on the microstructures and physical properties of BC,as well as the silver contents and the antibacterial performances of the BC/AgNPs composites were investigated.It was found that the AgNPs impregnated on the dried BC films were inclined to achieve a faster silver releasing rate than the wet one,which was suitable for acute traumas treatment.

Green and Effective Ammonium Carbonate-assisted Process for Drying Hemicellulose Obtained through Alkali Extraction of Bleached Bamboo Kraft Pulp

Hemicellulose has a wide range of applications,including that as an emulsifier for the food industry and raw material for the synthesis of bioethanol/biochemicals and biodegradable films.Hemicellulose is usually present as a spent liquor,such as the prehydrolysis liquor of the prehydrolysis kraft dissolving pulp production process and the alkali extraction liquor of the cold caustic extraction of pulp fibers.Due to its dilute nature,hemicellulose needs to be dried for practical utilization,and this is challenging.In this study,cellulose and hemicellulose in a bleached bamboo kraft pulp were separated using an alkali extraction process.Hemicellulose obtained from the extraction liquor was dried by an ammonium carbonate-assisted drying process.The effects of drying time and drying temperature were determined.Structure of the hemicellulose obtained by the ammonium carbonate-assisted drying process was similar to that of original hemicellulose,as revealed by detailed Fourier transform infrared and X-ray diffraction analyses.The novel drying method was more energy efficient and required a shorter drying time than the conventional freeze drying method,and the excellent solubility in alkaline solutions favored the chemical modification of hemicellulose.The dried hemicellulose can be used as a renewable raw material for the preparation of hydrogels and other substances such as bioethanol/biochemicals and biodegradable films.

Effect of Different Drying Processes on Active Ingredients of Rheum officinale Baill.

[Objectives]To determine the drying process of different functional rhubarbs.[Methods]The contents of tannins,bianthrone,free anthraquinones and combined anthraquinones in medicinal rhubarb were determined by HPLC.The results were analyzed by two-way analysis of variance.[Results]Under different drying conditions,the contents of tannins,bianthrone,free anthraquinones and combined anthraquinones in medicinal rhubarb were significantly different.Taking the tannins content as the index,the optimum drying condition of the rhizome is 1 cm thick,dried at 60℃,the root is cut 1 cm thick,and dried at 30℃;the bianthrone content is used as an indicator,the rhizome is optimally dried.The condition is to cut 1 cm thick,dry at 60℃,the root is cut to 5 cm thick,and dried at 40℃;the free anthraquinones content is used as an index,and the optimum drying condition of the rhizome is 3 cm thick and dried at 50℃.The root is cut to a thickness of 3 cm and dried at 30℃.The combine anthraquinones content is used as an indicator.The optimum drying conditions for the rhizome are 5 cm thick,dried at 40℃,and the root is cut to 5 cm thick and dried at 70℃.[Conclusions]Different functional components of rhubarb have different directional processing methods.The drying process can reduce the drying temperature or increase the thickness of the slice,and the directional processing of the diarrhea-type rhubarb can be processed.The drying process can be carried out by increasing the drying temperature or reducing the thickness of the slice directed processing of heat-clearing and purging-fire rhubarb.

Optimized Synthesis of Carbon Aerogels via Ambient Pressure Drying Process as Electrode for Supercapacitors

Carbon aerogels were synthesized via ambient pressure drying process using resorcinolformaldehyde as precursor and P123 to strengthen their skeletons. CO2 activation technology was implemented to improve surface areas and adjust pore size distribution. The synthesis process was optimized, and the morphology, structure, adsorption properties and electrochemical behavior of different samples were characterized. The CO2-activated samples achieved a high specific capacitance of 129.2 F/g in 6 M KOH electrolytes at the current density of 1 m A/cm^2 within the voltage range of 0-0.8 V. The optimized activation temperature and duration were determined to be 950 ℃ and 4 h, respectively.

APPLICATION OF CATIONIC STARCH BY DRY-PROCESS AS ANIONIC CHARGE NEUTRALIZING AGENTS TO IMPROVE FILLER RETENTION

This paper deals with the preparation of cationic starch with high degree of substitute by dry-process. The corn starch and the alkali catalyst are mixed in the mixer, then added the cationic etherifying agent (3-chloro-2-hydroxypropyltrimethylammonium chloride). The reacting time is for 5 hours at the temperature of 70℃. The cationic starch with high degree of substitution is used as anionic charge neutralizing agents to improve filler retention in wet-end section of papermaking machine.

Intensification of the Banana Drying Processes by Using EFL Electromagnetic Waves

Drying of the banana in the hot water has a negative impact on the quality of the product and drying effect. The purposes of this study are increasing the drying rate, using the relatively low temperature to improve the quality (40℃, 50℃ and 60℃) and investigate the use of electromagnetic waves to increase the drying speed. Therefore, experiments are performed using 5 kHz,10 kHz and 15 kHz low frequency electromagnetic waves in the air velocity values of 0.5 m/s, 1 m/s, 1.5 m/s and 2 m/s and 40℃, 50℃, 60℃ centigrade degrees of air blast in a special compartment. Mathematical model of the drying process has been created as using the electrical circuits methods and experimental results. As a result, a simple equation describing the drying process has been obtained. Nonlinear expression of the diffusion coefficient for a different situation in this equation has been identified for the first time. The obtained theoretical results and experimental results have been provided a good agreement. This study is considered to be useful for all studies in the drying area.

Numerical Study on Dry Deposition Processes in Canopy Layer

A coupling model between the canopy layer(CL) and atmospheric boundary layer (ABL) for the study of dry deposition velocity is developed. The model consists of six parts: chemical species conservation equation including absorptive factor; the species uptake action including detailed vertical variation of absorptive element in CL; momentum exchange in CL which is represented by a first-order closure momentum equation with an additional larger-scale diffusive term; momentum exchange in ABL which is described by a complete set of the ABL turbulent statistic parameters; absorptivity (or solubility or reflection) at the surface including effects of the physical and chemical characters of the species, land type, seasonal and diurnal variations of the meteorological variables; and deposition velocity derived by distributions of the species with height in CL. Variational rules of the concentration and deposition velocity with both height and time are simulated with the model for both corn and forest canopies. Results predicted with the bulk deposition velocity derived in the paper consist well with experimental data.

Experimental Study of Drying Process of COLZA Seeds in Fluidized Bed Dryer by Statistical Methods

In this study the effect of initial parameters such as inlet gas temperature, initial particles temperature and gas velocity on temperature changes of solid particles and outlet gas temperature in a fluidized bed dryer was studied. For testing, an experimental setup was established. With combination of air and Colza seeds belonging to D groups of the Geldart classification (Geldart, 1986) fluidization regime was carried out. With five test series with maintaining the inlet gas temperature, solid particle temperature and outlet gas temperature during time were carefully measured. To analyze these data by using regression analysis to predict solid particle and outlet gas temperature, 2 correlations on initial pa-rameters were presented. The result has shown that temperature gradients in the beginning of fluidization, is very high and therefore the exponential functions in the regression model is used to predict the temperature changes.

The Selection of Dry Port Location by Analytic Network Process Model: A Case Study of Dosso-Niger

The aim of this paper is to select the best location for the construction of a dry port in Niger which is a land locked country (LLC). Niger is located in the Sahel and has a land area of 1,267,000 square kilometers [1], with the closest port being port of Cotonou in Benin. The transport corridor from Niamey to Cotonou is approximately 1036 km long [2]. It is estimated that this corridor carries about 40 percent of Niger’s overseas trade traffic [3]. In this work, the Analytic Network Process (ANP) model is used to determine the optimal location of the dry port, among three major cities: Niamey (capital city), Dosso and Gaya. From the application of this selection model, Dosso was selected as the best location for the location of the dry port, while Gaya and Niamey were placed second and third respectively. The results obtained in this work strongly confirm the decision of the government of Niger to construct a dry port in Dosso, a project that commenced in 2010 and is still in progress.

High energy density in ultra-thick and flexible electrodes enabled by designed conductive agent/binder composite

Thick electrodes can increase incorporation of active electrode materials by diminishing the proportion of inactive constituents,improving the overall energy density of batteries.However,thick electrodes fabricated using the conventional slurry casting approach frequently exhibit an exacerbated accumulation of carbon additives and binders on their surfaces,invariably leading to compromised electrochemical properties.In this study,we introduce a designed conductive agent/binder composite synthesized from carbon nanotube and polytetrafluoroethylene.This agent/binder composite facilitates production of dry-process-prepared ultra-thick electrodes endowed with a three-dimensional and uniformly distributed percolative architecture,ensuring superior electronic conductivity and remarkable mechanical resilience.Using this approach,ultra-thick LiCoO_(2)(LCO) electrodes demonstrated superior cycling performance and rate capabilities,registering an impressive loading capacity of up to 101.4 mg/cm^(2),signifying a 242% increase in battery energy density.In another analytical endeavor,time-of-flight secondary ion mass spectroscopy was used to clarify the distribution of cathode electrolyte interphase(CEI) in cycled LCO electrodes.The results provide unprecedented evidence explaining the intricate correlation between CEI generation and carbon distribution,highlighting the intrinsic advantages of the proposed dry-process approach in fine-tu ning the CEI,with excellent cycling performance in batteries equipped with ultra-thick electrodes.

Application of Analytic Hierarchy Process in Selection of an Appropriate Drying Platform for Maize Drying in a Solar Bubble Dryer

The solar bubble dryer (SBD) is a convenient and better option to traditional open sun drying commonly practiced by smallholder farmers in Ghana and other developing countries. However, to operate the SBD, one is faced with the challenge of frequent mixing of grains using a rake to enhance uniform drying and prevent over-heating of the top-layer exposed to the sun. Additionally, condensation in the SBD can compromise the quality of grains during drying under humid conditions. In the present study, the Analytical Hierarchy Process (AHP) was used to select an appropriate drying platform, tarpaulin, or elevated drying rack for maize drying in the SBD. Using the AHP, the elevated drying rack was chosen as a suitable platform for drying maize in the SBD. The SBD with the elevated drying racks was used to dry 270 kg of maize from a moisture content of 18.2% to 12.6% (w.w.b) within 6 hours compared to 11 hours for the same quantity of grains dried on the tarpaulin of the SBD to reach an MC of 12.5% (w.w.b). An average drying rate and moisture extraction rate of 0.93%/h and 2.88 kg/h were achieved with the elevated drying rack system compared to 0.52%/h and 1.60 kg/h when drying on the tarpaulin of the SBD. An average temperature of 44.6°C recorded in the SBD was 9°C more compared to the ambient temperature. The thermal efficiency of the SBD collector was determined as 36.2%. Drying grains with the elevated racks showed advantages of reduced drying time, improved airflow through the drying bed, and prevention of condensation, which occurs when drying on the tarpaulin of the SBD.

不同润叶和复烤强度对上部烟叶质量的影响

以云烟87上部烟叶为研究对象,以颜色深浅度、色度、均匀度、油分、常规化学成分和感官质量为评价指标,开展了不同润叶和复烤强度对上部烟叶质量的影响研究。结果表明,随着润叶强度的增加,润叶后烟叶颜色逐渐加深,色度偏向深橘黄,均匀度逐渐变差,油分增加;复烤后烟叶颜色变浅,色度向柠檬黄转变,均匀度提升,油分降低,较高温度复烤的烟叶均匀度和油分优于低温复烤;随润叶强度增加烟叶烟碱和总糖含量逐渐升高,复烤后其含量逐渐下降;随润叶强度增加润叶后的感官质量逐渐降低,低水分润叶下随复烤温度增加感官质量提升,高水分润叶下随复烤温度增加感官质量下降。综合来看,低水分润叶(W15%)和较高温度复烤(T 70℃)更有利于上部烟叶质量的形成。

软模板法制备聚苯胺干凝胶及在水性防腐涂料中的应用

分别以双十八烷基二甲基氯化铵和双十二烷基二甲基氯化铵为软模板,采用化学氧化法制备聚苯胺干凝胶。通过傅里叶变换红外光谱(FT-IR)、扫描电镜(SEM)等对聚苯胺干凝胶进行结构表征;将制备的聚苯胺干凝胶应用于水性防腐涂料中,考察其对水性涂料防腐性能的影响。结果表明,制得的聚苯胺水性防腐涂料具有较好的耐水、耐酸、耐碱、耐中性盐雾性。

枸杞子产地加工研究进展

目的:为枸杞子产地加工的现代化研究提供理论依据,为其新药开发和质量评价奠定基础。方法:通过数据库的检索,对近些年枸杞子产地加工过程中所涉除蜡及干燥工艺的相关文献资料进行整理与总结。结果:枸杞子除蜡主要包括Na2CO3除蜡、碱性油酸乙酯溶液除蜡等化学除蜡法和超声除蜡、研磨除蜡等物理除蜡法;枸杞子干燥主要包括自然晾干、热风干燥等热力干燥和微波干燥、冷冻干燥等非热力干燥。经实地调研和相关文献查阅发现,除蜡过程与干燥过程所涉工艺存在一定差异,且相关工艺参数缺乏统一标准。结论:目前枸杞子的产地加工研究较为全面,工艺研究多是对枸杞子干果营养成分及品质的影响,目前暂未见对药理、药效影响的报道。

国内外油页岩工业发展现状

油页岩可作为锅炉燃料直接燃烧产生蒸汽发电,也可经热解后分解生成页岩油、页岩半焦和类似天然气的干馏气,是石油的重要补充能源,开发前景广阔,对世界能源结构的改变具有重要战略意义。梳理世界主要油页岩国家油页岩资源特点、加工利用技术和开发利用现状,世界各国对油页岩的勘探、开采和干馏技术不断革新提升,包括爱沙尼亚、巴西、美国在内的许多国家已经拥有了较先进的油页岩处理技术,对油页岩进行合理开采并进行产业化利用。目前,中国在抚顺、新疆、甘肃等地加工利用油页岩,抚顺页岩油年产量最大。与世界主要油页岩国家相比,中国油页岩开发利用程度总体较低,新技术开发利用不够成熟,尚未形成以油页岩为基础的完整产业链,未来发展还需要更多相关国家政策支持,进一步加大油页岩的科研投入,研究开发适应中国特点的新型技术,不断提高油页岩的工业利用水平和资源化利用水平,在提高处理量、产油率的同时减少生态污染,坚持走新型工业化道路。

膨润土矿物选矿提纯方法研究

膨润土是我国的一种优势资源,其主要矿物成分为层状结构的蒙脱石,但天然膨润土中蒙脱石的含量不高,一些低质的膨润土蒙脱石含量仅在50%左右,杂质含量较高,必须经过提纯才能用于开发高端产品。膨润土提纯方法及效果一直是行业急需的技术,但不同的膨润土性能及伴生的杂质不同,提纯方法不同,针对膨润土提纯方法的现状,通过综述回顾膨润土提纯的研究进展,为膨润土提纯在实际生产中应用提供指导。