纯碱法去除卤水中锶元素分析与控制

本文结合盐化工业生产实际,论述纯碱法去除卤水中锶元素的方法,分析影响卤水中锶含量的因素,指出生产过程中的控制方法,并对产生的经济效益进行估算。     

锶的分离检测方法研究进展

锶是高放废水中主要的释热裂变产物之一,同时也是重要的战略资源。从卤水矿物资源或废水以及环境水中分离提取锶,具有重要现实意义。对锶进行有效的分离检测是首要解决的问题。文章综述了多种水样品中锶含量测定所涉及分离与检测方法的研究进展,包括预处理、预富集以及沉淀、离子交换、溶剂萃取和萃取色谱等技术,并比较了不同方法在选择性、时效性和适用性上的差异,探讨了锶分离检测方法研究的发展方向。     

ICP-AES法测定天然卤水中11种元素

建立一种采用电感耦合等离子体原子发射光谱法(ICP-AES)测定天然卤水中钾、钠、钙、镁、锶、锂、硼、铜、铁、锰、锌11种元素含量的方法。样品经过简单稀释后即可测试,元素检出限为0.000 7 mg/L~2.4 mg/L,加标回收率为91.6%~108%,相对标准偏差(RSD)2%。方法简单快速,精密度好,准确度高,适用于天然卤水中钾、钠、钙、镁、锶、锂、硼、铜、铁、锰、锌元素的分析。     

卤水空气吹出法制溴对海盐生产的影响

海盐中度卤水制溴工艺中,会引入其它离子进卤水,导致卤水成分及性质发生变化。文章对比提溴前后卤水成分的变化,分析了提溴后卤水对海盐生产的影响,提出一些存在的问题和解决方法。     

精制盐生产中卤水增浓盐量测算问题的探讨

文章通过对公司精制盐生产原料卤水浓度及含盐量有时不能满足实际生产需要的问题进行了分析,从而说明了原料卤水需要加盐以便提高卤水浓度的必要性。在此基础上,对实际生产中原料卤水加原盐增浓过程中存在的一些问题进行分析,并进一步说明了精制盐生产中原料卤水增浓加盐量测算的重要性。通过探讨测算依据,确定测算标准以及采用实际消耗量与测算标准进行对比等方法,力求达到测算的实用性,以实现生产的经济运行。     

浅析原料卤水净化试验方法

在盐品生产中,原料卤水杂质组分较高对盐产品质量影响严重,此方法论述了如何从源头上去除原料卤水的杂质离子,达到既经济又能产出高质量盐产品的卤水净化方案。     

氯水氧化法和自动控制在四川蓬莱盐厂制碘生产中的应用

四川蓬莱地下卤水具有矿化度高,多元素富集等特点。蓬莱盐厂除生产食盐外,还生产碘、溴、硫酸钡、碳酸锶、氯化钙等化工原料。其中碘素1967年投产,采用制盐母液做原科,氯气氧化,空气吹出法生产。生产过程中,原料首先酸化,要求把原料的 PH 值调到2—3。如果制盐母液的 PH=5～5.5,调至 PH=2～3,则每生产一吨碘需耗盐酸20吨左右。地下卤水在制盐前加石灰把 PH 调至9,制盐后制碘前又加盐酸把 PH 调至2～3,在制碘后制锶前又加石灰把 PH 调到9～8。另外在制盐过程中碘约损失20～30%,从全厂来看这种工艺流程是     

芒硝型和盐型卤水两碱法除钙镁的实验研究

通过实验和生产相结合的方法,针对芒硝型卤水和盐型卤水中两碱法去除钙镁离子的效果进行了研究。     

一种多井卤水差别化处理装置及其方法

针对多井卤水的差异性,采用了一种卤水差别化处理装置及方法,成功的应用于生产,提高了卤水质量,确保了成品盐质量和生产系统的安全稳定运行,降低了卤水处理成本,解决了卤井之间含杂质量的差异性引发的一系列问题,为岩盐井下卤水处理工艺技术的稳定运行提供了保障。     

桂林卤水HPLC指纹图谱建立及其质量评价研究

为了建立更合理的桂林卤水质量评价标准,试验摸索建立了桂林卤水的HPLC指纹图谱。通过对10批次桂林卤水成品计算其相关系数相似度、程度相似度和数量相似度,各参数作为评定桂林卤水质量的标准指数,综合评定其质量。企业生产过程中得到的桂林卤水成品,通过与该桂林卤水指纹图谱建立生成的对照指纹图谱进行对比,计算其程度相似度和数量相似度参数,再与质量标准指数对比,即可得出生产质量是否合格。该综合评价方法的建立,为相关企业的桂林卤水质量控制标准的建立提供了更合理、科学的技术手段。     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.     

低温带皮菜籽粕微粉的不同粒级部分的功能特性

为研究低温带皮菜籽粕微粉的不同粒级部分的功能特性,以经低温脱脂的带皮菜籽粕为原料,经微粉碎后筛分成212~425μm、150~212μm和106~150μm的3个不同粒级的微粉样品,检测这些样品的吸水性、吸油性、乳化性和乳化稳定性、蛋白质体外消化率。结果表明:1 3个不同粒级的微粉样品之间的粗纤维含量存在显著差异,表明三者的结构组成成分有一定差异。23个微粉样品的乳化活性和乳化稳定性随粒度级别的减小而显著增加(P0.01)。33个微粉样品的蛋白质体外消化率随粒度级别的减小而显著增加(P0.01)。4不同粒级带皮菜籽粕微粉样品的吸水性与吸油性受其结构组成物质不同和粒度的双重影响,与粒度的相关性不明显。     

Microbiology of food taints

Fresh and processed foods are often spoilt by the presence of undesirable flavours and odours caused by microbial action. The aim of this paper is to review the current knowledge of microbiologically induced taints that occur in a wide range of foodstuffs, including meats, poultry, fish, crustaceans, milk, dairy products, fruits, vegetables, cereals and cereal products. Examples have been chosen where the compounds responsible for the taint have been identified and sufficient data obtained to demonstrate the involvement of microorganisms. However, in some cases the full identity of the causative organism may not have been elucidated. The types of microorganisms covered by this review include bacteria, fungi, yeasts, actinomycetes and cyanobacteria. Although cyanobacteria do not in general infect foods, their presence in aqueous systems and water supplies can lead to off-flavours in aquatic organisms and processed foodstuffs. Several examples of each of these processes are discussed. Wherever possible, the likely biosynthetic pathway used by the microorganism to produce the offending compound in a foodstuff is indicated.     

Analysis for organic residues from aids to polymerization used to make plastics intended for food contact

Polymers intended for food contact use have been analysed for organic residues which could be attributed to a range of substances employed as polymerization aids (e.g. initiators and catalysts). A wide range of polymers was extracted with solvents and the extracts analysed by gas chromatography-mass spectrometry (GC-MS). The overwhelming majority of substances identified were not derived from aids to polymerization but were oligomers, additives and adventitious contaminants. However, a small number of substances were identified as initiator residues. These included tetramethylsuccinonitrile (TMSN) which was observed in two polymers and it derived from recombination of two azobisisobutyronitrile (AIBN) initiator radicals. Methyl benzoate, benzoic acid, biphenyl and phenyl benzoate were detected in one poly(methyl methacrylate) sample and in two polyvinylchlorides and they are thought to be derived from benzoyl peroxide initiator. TMSN was subsequently targeted for analysis of poly-(methyl methacrylate) plastics using proton nuclear magnetic resonance spectrometry (¹     

Tests of potential functional barriers for laminated multilayer food packages. Part II: Medium molecular weight permeants

Experiments were performed to characterize the kinetics of the permeation of different medium molecular weight model permeants: bisphenol A, warfarin and anthracene, from liquid paraffin, through a surrogate potential functional barrier (25 microns-thick orientated polypropylene--OPP) into the food simulants olive oil and 3% (w/v) acetic acid. The characterization of permeation kinetics generally observed the permeation models previously reported to explain the experimental permeation results obtained for a low molecular weight group of model permeants. In general, the model permeants exhibited behaviour consistent with their relative molecular weights with respect to (a) the time taken to attain steady-state permeation into the food simulant in which they were more soluble, (b) their subsequent steady-state permeation rates, and (c) their partition between liquid paraffin and the OPP membrane.     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. I: Interlaboratory studies of methods of analysis

This paper describes the first part of a project undertaken to develop mussel reference materials for Paralytic Shellfish Poisoning (PSP) toxins. Two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin (STX) and decarbamoyl-saxitoxin (dc-STX) in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the second part of the project: the certification exercise. In the first study, 18 laboratories were asked to measure STX and dc-STX in rehydrated lyophilized mussel material and to identify as many other PSP toxins as possible with a method of their choice. In the second interlaboratory study, 15 laboratories were additionally asked to determine quantitatively STX and dc-STX in rehydrated lyophilized mussel and in a saxitoxin-enriched mussel material. The first study revealed that three out of four postcolumn derivatization methods and one pre-column derivatization method sufficed in principle to determine STX and dc-STX. Most participants (13 of 18) obtained acceptable calibration curves and recoveries. Saxitoxin was hardly detected in the rehydrated lyophilized mussels and results obtained for dc-STX yielded a CV of 58% at a mass fraction of 1.86 mg/kg. Most participants (14 out of 18) identified gonyautoxin-5 (GTX-5) in a hydrolysed extract provided. The first study led to provisional criteria for linearity, recovery and separation. The second study revealed that 6 out of 15 laboratories were able to meet these criteria. Results obtained for dc-STX yielded a CV of 19% at a mass fraction of 3.49mg/kg. Results obtained for STX in the saxitoxin-enriched material yielded a CV of 19% at a mass fraction of 0.34mg/kg. Saxitoxin could not be detected in the PSP-positive material. Hydrolysis was useful to confirm the identity of GTX5 and provided indicative information about C1 and C2 toxins in the PSP-positive material. The methods used in the second interlaboratory study showed sufficiently consistent analysis results to undertake a certification exercise to assign certified values for STX and dc-STX in lyophilized mussel.     

The Ministry of Environmental Protection Issued "Feasible Technology Guidelines for Pollution Prevention and Control in Wood Pulping Process of the Paper Industry (Trial)" and Two Other Guiding Technical Documents

On December 27t＂, 2013, the Ministry of Environmenta Protection announced that, in order to implement ＂The Environmental Protection Law of the People＇ s Republic of China＂, improve the working system in environmenta protection technologies, and promote technologica advancement in pollution prevention, the Ministry of Environmental Protection sponsored the formulation of three guiding technical documents including ＂Feasible Technology Guidelines for Pollution Prevention and Contro n Wood Pulping Process of the Paper Industry （Trial）＂     

1~(st) Intelli-Tissue~ EcoEc Tissue Machine Supplied by PMP Group Successfully Put into Operation in China

正On April 29th,2014,Intelli-Tissue EcoEc tissue machine supplied by PMP Group successfully put into operation at Hebei Xuesong Paper Co.,Ltd.,this is the first such kind of paper machine of PMP Group in China.