红薯粉渣酸化料对蛋鸭产蛋性能和蛋品质的影响

探讨红薯粉渣酸化料对蛋鸭产蛋性能和蛋品质的影响,对照组及试验1、2和3组分别饲喂添加0%、1.5%、3.0%和4.5%红薯粉渣酸化料的日粮。结果表明:与对照组相比,试验2组产蛋率和日产蛋重分别提高6.72%和7.70%(P<0.05),蛋白高度和哈氏单位分别提高14.03%和11.53%(P<0.05);试验各组与对照组相比,日均采食量和蛋黄色泽有提高的趋势但差异不显著。综合考虑各项性能指标,蛋鸭饲料中添加3%的红薯粉渣酸化料较为理想。

粉渣酸化料对断奶仔猪生产性能的影响

本试验旨在研究粉渣酸化料对断奶仔猪生产性能的影响。试验采用单因子随机分组设计,选取30日龄三元杂交(杜×长×大)仔猪96头,随机分成4组(对照组和试验1、2、3组),每组3个重复,分别饲喂含0、1%、3%、6%粉渣酸化料的日粮,试验为期5周。结果表明:试验2组、试验3组与对照组相比日均采食量显著提高(P<0.05);与对照组相比,试验1组、2组和3组平均日增重显著提高(P<0.05),而腹泻指数显著降低(P<0.05)。可见粉渣酸化料可提高断奶仔猪生产性能,饲料中添加2%的粉渣酸化料效果较理想。

粉渣酸化料对奶牛产奶性能的影响

为在探讨粉渣酸化料对奶牛产奶性能的影响,选择年龄、胎次、泌乳月、产奶量等基本一致的30头奶牛分成3组,对照组饲喂全混合日粮(TMR),试验1组、2组和3组在TMR日粮基础上用2kg、4kg、6kg粉渣酸化料替代啤酒糟,试验持续30d,结果表明与对照组相比试验2组和3组产奶量显著提高(P<0.05),乳蛋白显著提高(P<0.05。可见粉渣酸化料能提高奶牛的产奶性能,全混合日粮中4kg粉渣酸化料替代啤酒糟效果较好。

红薯粉渣酸化料对肉鸭生长性能和消化酶活性的影响

试验旨在探讨添加2%、4%、6%的红薯粉渣酸化料对肉鸭生长性能和消化酶活性的影响。试验结果表明:各处理组的平均日增重及脂肪酶、胰蛋白酶活性有上升的趋势,其中4%红薯粉渣料处理组平均日增重及脂肪酶、胰蛋白酶活性显著提高(P<0.05),可见红薯粉渣酸化料能够提高肉鸭的生长性能和消化酶活性,且4%红薯粉渣酸化料添加组效果较理想。

粉渣酸化料在肥育猪生产中的应用

为了在肥育猪生产中应用粉渣酸化料，试验探讨了日粮中添加粉渣酸化料对育肥猪生长性能的影响。试验采用单因子随机设计，选用体质量65kg左右、日龄相近、体质良好的杜长大三元杂交猪40头．随机分为4组（试验1,2、3组和对照组），分别饲喂含有0、2％、铂和6％粉渣酸化料的日粮。结果表明：与对照组相比试验1组、2组、3组日均采食量显著提高（P〈0．05），腹泻指数显著降低（P〈0．05）；试验1组和2组平均日增重较对照组显著提高（P〈0．05）。可见粉渣酸化料能提高育肥猪的生长性能，综合各组指标．饲料里添加4％粉渣酸化料效果较好。

酸化红薯粉渣对肉兔生长性能、免疫器官指数和胃肠pH的影响

为探讨酸化红薯粉渣对肉兔生长性能、免疫器官指数和胃肠pH的影响,试验采用单因子完全随机分组设计,选取128只（公母各半）50日龄体重相近的新西兰兔随机分为4个处理组（对照组、试验1组、2组和3组）,每组4个重复,分别饲喂含0%、5%、10%、15%酸化红薯粉渣的饲粮。结果表明,与对照组相比,试验2组和3组肉兔日均采食量、平均日增重、胸腺指数和脾脏指数均显著提高（P〈0.05）,胃pH显著降低（P〈0.05）;试验1、2和3组腹泻率、十二指肠pH、盲肠pH均有所降低（P〉0.05）。由此可见,在饲料中添加适量的酸化红薯粉渣能提高肉兔的生长性能和免疫器官指数,降低胃肠pH,其中添加量为10%~15%效果较理想。

硫酸法由富钛高炉渣中提取钛

攀枝花含钛高炉渣是一种重要的、待开发利用的钛资源。本文介绍采用以含钛高炉渣进行“选择性分离”后的富钛精矿为原料 ,研究硫酸法提取钛过程中渣酸比、温度、渣粒度以及硫酸浓度对钛元素酸解率的影响 ,钛元素最高酸解率可达 98%以上 ,为实现从高炉渣中回收钛提供了理论基础。

含氰废水选择性浸出酸化渣中铜的试验研究

针对某黄金冶炼企业酸化渣中铜的回收进行研究,提出利用含氰废水浸出酸化渣中的铜。通过控制浸出条件(浸出温度、初始pH和浸出时间)以抑制锌、铁浸出,达到溶液净化的目的,便于后续铜的富集与回收。利用热力学计算和浸出试验相结合,研究酸化渣中铜的浸出和锌、铁净化反应路径。热力学计算结果表明:在碱性条件下,当n(总氰化合物)/n(Cu)=1.71时,硫氰化亚铜被游离氰化物络合全部转化为Cu-CN络合物;当n(总氰化合物)/n(Cu)=5.0时,与锌络合的氰化物被铜全部占据形成Cu-CN络合物。在浸出温度333.15 K,初始pH值11.0,浸出时间120 min和液固比100∶1的条件下,铜浸出率可达99.72%;浸出液中锌和铁质量浓度几乎为零,二者主要以Na_(2)Zn_(3)[Fe(CN)_(6)]_(2)沉淀形式进入浸出渣中。

Preparation of Ti-rich material from titanium slag by activation roasting followed by acid leaching

A method of activation roasting followed by acid leaching using titanium slag was introduced to prepare Ti-rich material. The effects of HaPO4 dosage, roasting temperature, and roasting time on TiO2 grade were investigated. A Ti-rich material containing 88.54% TiO2, 0.42% （CaO＋MgO） was obtained when finely ground titanium slag was roasted with 7.5% H3PO4 at 1000 ℃ for 2 h, followed by a two-stage leaching in boiling dilute sulfuric acid for 2 h. The XRD patterns show that the product is titanium dioxide with a rutile structure. Mechanism studies show that structures of anosovite solid solution and silicate minerals are destroyed in the roasting process. As a result, titanium components in titanium slag are transformed into TiO2 （futile） while impurities are transformed into acid-soluble phosphate and quartz.

Extraction of vanadium from molten vanadium bearing slag by oxidation with pure oxygen in the presence of CaO

A novel process of vanadium extraction from vanadium slag in its molten state was conducted at the laboratory scale by oxidation with pure oxygen in the presence of CaO. The effect of mass ratio of CaO to V2O5 on the recovery of vanadium was studied. The sintered samples were leached by H2SO4 solution and characterized by XRD, XPS, SEM and EDS techniques. Compared with the roasting process, the energy saving effect of the proposed process was also discussed. The results showed that vanadium-rich phases were formed and vanadium mainly existed in the forms of CaV2O5 and Ca2V2O7. The formation mechanism of calcium vanadates in the molten vanadium bearing slag was explained. The XRD and XPS results implied that there was a limit to the oxidation reaction of V(IV) to V(V) under the high temperatures even though oxygen-supply was sufficient. An increase in the CaO content led to an increase in the formation of Ca2V2O7. About 90%of the vanadium recovery was obtained under optimal experiment conditions (mass ratio of CaO to V2O5 of 0.6, particle size 120 to 150μm, leaching temperature 90 °C, leaching time 2 h, H2SO4 concentration 20%, liquid to solid ratio 5:1 mL/g, stirring speed 500 r/min). The energy of 1.85×106 kJ could be saved in every 1000 kg of vanadium bearing slag using the proposed process from the theoretical calculation results. Recovery of vanadium from the molten vanadium bearing slag and utilisation of its heat energy are important not only for saving metal resources, but also for energy saving and emission reduction.

Reaction kinetics of roasting high-titanium slag with concentrated sulfuric acid

A novel method of roasting high-titanium slag with concentrated sulfuric acid was proposed to prepare titanium dioxide, and the roasting kinetics of titania was studied On the basis of roasting process. The effects of roasting temperature, particle size, and acid-to-ore mass ratio on the rate of roasting reaction were investigated. The results showed that the roasting reaction is fitted to a shrinking core model. The results of the kinetic experiment and SEM and EDAX analyses proved that the reaction rate of roasting high-titanium slag with concentrated sulfuric acid is controlled by the internal diffusion on the solid product layer. According to the Arrhenius expression, the apparent activation energy of the roasting reaction is 18.94 kJ/mol.

Preparation of electronic grade manganese sulfate from leaching solution of ferromanganese slag

Preparation of electronic grade manganese sulfate from ferromanganese slag, including grinding, leaching and purification, was studied. The impurities, such as Fe3+, Al3+, Ca2+, Mg2+, heavy metal ions and Na+, K+, were removed from leaching solution by neutralized-hydrolysis, fluorination precipitation, sulfuration precipitation and re-crystallization. Effects of pH of reaction, temperature and dosage of the different additives on removal rates of the metallic ions in leaching solution were investigated, and the suitable temperature, pH and the added amount of precipitating agent were obtained. The prepared manganese sulfate product, of which the mass fractions of Ca2+, Mg2+, Na+, K+ are all smaller than 0.005%, the mass fractions of Fe3+, Al3+ and heavy metal ions are smaller than 0.001%, and the mass fraction of Mn2+ is greater than 32%, can meet the demand of anode materials of lithium-ion batteries.

Removal of magnesium and calcium from electric furnace titanium slag by H_3PO_4 oxidation roasting-leaching process

H3PO4 oxidation roasting followed by HCl acid leaching was proposed to remove magnesium and calcium from electric furnace titanium slag containing 3.12% MgO and 0.86% CaO. XRF, XRD and SEM techniques were used to characterize the composition, mineral phase component and microstructure of the titanium slag. The H3PO4 oxidation thermodynamic, mineral phase transformation, microstructure, element distribution in titanium slag during H3PO4 oxidation process and leaching process were investigated. The thermodynamic analysis indicated that H3PO4 could promote the decomposition of MgTi2O5 and CaSiO3. The results indicated that H3PO4 could effectively promote the transformation of titanium-bearing mineral to rutile and enrich the impurities in MxTi（3-x）O5 into phosphate which could be removed by acid leaching process. Under the studied conditions, the leaching rates of magnesium and calcium reached 94.68% and 87.19%, respectively. The acid leached slag containing 0.19% MgO and 0.13% CaO（mass fraction） was obtained.

Secondary reaction mechanism of leaching process of calcium aluminate slag

SiO2 in calcium aluminate slag exists in the form of γ-2CaO·SiO2 which is more stable than β-2CaO·SiO2. However, it is decomposed by sodium carbonate solution during leaching process, leading to the secondary reaction. The extent of secondary reaction and reaction mechanism of calcium aluminate slag were studied using XRD. The results show that the decomposition rate of γ-2CaO·SiO2 increases with the increase in leaching time and sodium carbonate concentration. The main products of secondary reaction are the mixture of hydrogarnet and sodium hydrate alumina-silicate. SiO2 concentration rises firstly and then drops with the increase of leaching temperature. XRD results indicate that the stable product of secondary reaction at low temperature is hydrogarnet. But hydrogarnet is transformed into sodium hydrate alumina-silicate at high temperature.

Effect of Na_2O on alumina leaching property and phase transformation of MgO-containing calcium aluminate slags

In order to remove or reduce the negative effect of MgO in calcium aluminate slags, the method of adding Na2O into calcium aluminate slags was studied and its effect on leaching mechanism was also analyzed. The results show that the alumina leaching efficiency of the calcium aluminate slag increases from 68.73% to 80.86% with Na2O content increasing from 0 to 4% when MgO content is 3%. The XRD results show that the quaternary compound C20A13M3S3 disappears when Na2O content increases to 4%. The addition of Na2O cannot remove the negative effect of MgO on leachability completely. XRD and EDS results indicate that Na2O can come into the lattice of 12CaO·7Al2O3 and promote the formation of 12CaO·7Al2O3

Novel method to prepare sodium chromate from carbon ferrochrome

An oxidizing roasting process of carbon ferrochrome to prepare sodium chromate in the presence of sodium carbonate and air was investigated. The effects of reaction temperature, reaction time, mole ratio of sodium carbonate to carbon ferrochrome were studied, and thermodynamics and kinetics of the reaction were also discussed. It was observed that there was a sudden increase in reaction rate when the temperature rose to a certain value, and the sample with a smaller grain size could start the sudden increase at a lower temperature. The chromium recovery rate increased with the increase of mole ratio of sodium carbonate to carbon ferrochrome, and it reached up to 99.34% when mole ratio of sodium carbonate to carbon ferrochrome increased to 1.2:1. The chromium residue yielded from this method was only about 1/3 of the product. Moreover, the content of Fe in the residue was as high as 60.41%. Therefore, it can be easily recovered to produce sponge iron, realizing complete detoxication and zero-emission of chromium residue.

Recovery of valuable metals from zinc leaching residue by sulfate roasting and water leaching

Zinc leaching residue(ZLR),produced from traditional zinc hydrometallurgy process,is not only a hazardous waste but also a potential valuable solid.The combination of sulfate roasting and water leaching was employed to recover the valuable metals from ZLR.The ZLR was initially roasted with ferric sulfate at640°C for1h with ferric sulfate/zinc ferrite mole ratio of1.2.In this process,the valuable metals were efficiently transformed into water soluble sulfate,while iron remains as ferric oxide.Thereafter,water leaching was conducted to extract the valuable metals sulfate for recovery.The recovery rates of zinc,manganese,copper,cadmium and iron were92.4%,93.3%,99.3%,91.4%and1.1%,respectively.A leaching toxicity test for ZLR was performed after water leaching.The results indicated that the final residue was effectively detoxified and all of the heavy metal leaching concentrations were under the allowable limit.

Lithium and manganese extraction from manganese-rich slag originated from pyrometallurgy of spent lithium-ion battery

Mn and Li were selectively extracted from the manganese-rich slag by sulfation roasting−water leaching.The extraction mechanisms of Mn and Li were investigated by means of XRD,TG−DSC,and SEM−EDS.73.71%Mn and 73.28%Li were leached under optimal experimental conditions:acid concentration of 82 wt.%,acid-to-slag mass ratio of 1.5:1,roasting temperature of 800°C,and roasting time of 2 h.During the roasting process,the manganese-rich slag first reacted with concentrated sulfuric acid,producing MnSO_(4),MnSO_(4)·H_(2)O,Li_(2)Mg(SO_(4))_(2),Al_(2)(SO_(4))_(3),and H_(4)SiO_(4).With the roasting temperature increasing,H_(4)SiO_(4) and Al_(2)(SO_(4))_(3) decomposed successively,resulting in generation of mullite and spinel.The mullite formation aided in decreasing the leaching efficiencies of Al and Si,while increasing the Li leaching efficiency.The formation of spinel,however,decreased the leaching efficiencies of Mn and Li.

Recovery of lead and silver from zinc acid-leaching residue via a sulfation roasting and oxygen-rich chlorination leaching method

A large amount of acid-leaching residue is produced during the conventional Zn hydrometallurgy process,and this residue has a large concentration of a variety of valuable metals.The purpose of this study was to evaluate the ability of a procedure that entails the use of sulfation roasting,water leaching,and chlorination leaching(blowing oxygen technique)to recover Pb and Ag,followed by cooling crystallization and the replacement of Ag with lead sheet,to realize the full recovery of all valuable metals from zinc acid-leaching residue;consequently,good results were achieved.The best results were obtained under the following conditions:a sulfuric acid at 70%of the raw material quality,roasting temperature of 300°C and roasting time of 2 h,followed by the process of leaching the roasted residue for 1 h by applying a water-to-solid ratio of 5꞉1 at room temperature.The recovery rates of Zn and Fe were 98.69%and 92.36%,respectively.The main parameters of the chlorine salt leaching system were as follows:Cl−concentration of 300 g/L,Fe3+concentration of 25 g/L,acid concentration of 2 mol/L,liquid-to-solid ratio of 9 mL:1 g,temperature of 90℃,and leaching time of 0.5 h;this leaching process was followed by filtration separation.These conditions resulted in high extents of leaching for Pb and Ag(i.e.,98.87%and 96.74%,respectively).Finally,the kinetics of the process of Ag leaching using Cl−ions in an oxygen-rich medium was investigated.It was found that the leaching process was controlled by the diffusion of the product layers,and the activation energy was 19.82 kJ/mol.

Stabilization of ferric arsenate sludge with mechanochemically prepared FeS2/Fe composites

FeS2/Fe composites were mechanochemically prepared with iron powder and pyrite for the stabilization of ferrite arsenate sludge(FAS).The effects of preparation parameters on stabilization performance were investigated.The results show that the optimum conditions are FeS2/Fe molar ratio of 5:5,milling time of 2 h,ball-to-material mass ratio of 15:1 and milling with stainless steel ball.Then,the composites were characterized by XRD,SEM,FTIR,etc.The physicochemical properties of FeS2/Fe mixture change dramatically,which is responsible for its excellent performance.Finally,the stabilization process of FAS was optimized.When the FAS is mixed with composites at mass ratio of 4:1 and milled for 30 min,the As leaching concentration of FAS can be reduced from 639.15 to 4.74 mg/L with the stabilization ratio of 99.2%.