利用废胶渣生产雷米邦 A的技术研究

利用熬胶剩余的废弃物胶渣作为生产雷米邦 A的主要原料,研究其合成的最佳工艺及条件,方法简单,收率高,效果好,成本低,技术可行,适用于中小型企业生产。     

阳涂感光胶含酚废水处理

阳涂感光胶含酚废水处理１前言阳涂感光胶是由感光性树脂、酚醛树脂、染料及溶剂组成的高粘度液体。其中制酚醛树脂的主要原料是混合甲酚，在树脂合成过程中有含酚废水产生，其主要污染成分是混合甲酚，废水静置后可分层，上层为水层，含酚２２２８ｍｇ／Ｌ；下层为酚层，...     

低醛环保型聚乙烯醇缩甲醛系列粘合剂问世

聚乙烯醇在酸性条件下与甲醛反应生成的聚合物 ,即聚乙烯醇缩甲醛胶 ,比聚乙烯醇溶液具有粘接力强、粘度大、耐水性强、成本低廉等优点 ,广泛应用于多种壁纸、纤维墙布、瓷砖粘贴、内墙涂料及多种腻子胶的粘合剂等 ,是我国合成胶粘剂的大宗品种之一 ,我国的消费量达 2 0 0ｋｔ/ａ以上。该胶粘剂因游离甲醛含量过高 ,刺激人的眼睛及呼吸系统 ,危害人体健康 ,发达国家早已禁用 ,我国北京、四川等地也制订了地方法规 ,禁止聚乙烯醇缩甲醛胶 (10 6胶、10 7胶 )用于室内装饰装修。为了规范市场、保护居民健康 ,国家质量监督检验检疫总局会同国家…     

碱激发胶凝材料的现状及应用

碱激发胶凝材料作为一种新型建筑材料,具有生产成本低、原材料易得、力学性能高、绿色环保且耐火、耐腐蚀及耐久性好等特点,很大程度上可替代传统硅酸盐水泥,符合可持续发展战略要求.对碱激发胶凝材料的激发剂、原材料、反应产物及形成机理进行概括,综述了其在各行业的应用情况并对其发展进行了展望.     

我国废橡胶资源综合利用现状

1 我国废橡胶资源综合利用历史 我国废橡胶资源利用除了直接原形利用或简单加工后供作鞋底、胶桶、船用靠坝、胶线绳等产品外,主要是生产再生胶和胶粉. 我国利用废橡胶生产再生胶开创于1930年,生产方法主要是油法,产品质量差、产量低,解放以前发展十分缓慢,最高年产量为8 000 t,到解放前的1949年降到500 t.     

铬铁渣透水混凝土制备及性能优化

在采用正交试验方法,对铬铁渣透水混凝土进行研究的基础上,又对其配比和性能进行了优化,结果表明:水胶比和胶骨比是影响铬铁渣透水混凝土性能的主要因素;成型方式、加入减水剂和可再分散乳胶粉均可影响其性能,在胶骨比为0.31,水灰比在0.30～0.40时,合适的成型方式和减水剂用量可制得满足规范要求的透水混凝土。     

高纯二氧化锆生产过程中污染的防治

对高纯二氧化锆的生产工艺进行了改革,采用了新型反应器及胶凝除硅,直接酸溶重结晶,直接煅烧等技术,降低了原材料消耗及能耗,减少了废液排放量,并将回收的废物加工成副产品白炭黑,实现了在生产过程中防治污染。     

化学法清洗脱硫塔与脱碳塔

合成氨厂半水煤气脱硫塔、变换气脱硫塔及脱碳塔常发生堵塔等现象,尤以半水煤气脱硫塔更为常见,变换气脱硫塔次之,严重影响了生产的正常进行。造成堵塔的因素比较复杂,与脱硫塔内所用填料、脱硫药剂、脱硫液中悬浮硫的多少及生产工艺条件等有关。在半水煤气脱硫中,使用烤胶及浓度高的V2O5脱硫液,发生堵塔的几率比使用其它脱硫药剂相对较大。有些合成氨厂采用降低烤胶、V2O5的浓度,加大脱硫塔直径及增加脱硫液的循环量的方法,以减少脱硫塔发生堵塔的可能性,取得了较好的效果。     

高含水油泥调质脱稳用剂

高含水油泥主要来自于页岩气田、油气田和炼厂的污水处理场（站）,含水率一般高达90%以上,成分复杂、乳化严重,是性质稳定的多相体系。破胶脱稳是高含水油泥处理处置与利用的前提,也是减量化的瓶颈,其核心是调质脱稳用剂的优选。介绍了高含水油泥的性质及调质脱稳的原理和方法,阐述了高含水油泥调质脱稳用剂的研究及应用现状,总结了助滤剂、氧化剂、电解质、破乳剂、絮凝剂和微乳化剂等常用药剂的调质机理、适应范围、研究实例和优缺点,并提出了调质脱稳用剂未来的发展方向。     

综合利用己二胺焦油开发系列精细化工产品

由己二腈加氢生产尼龙６６中间己二胺的过程中，副产大量重组分焦油，可用于制备环氧树脂固化剂，印染助剂，造纸助剂，原油处理剂，絮凝剂，沥青胶改进剂，沥青乳化剂，阻垢剂，表面活性剂及胶粘剂等多种精细化工产品，本文对有关产品的制备及性能进行了阐述。     

Determination of the Thermal Efficiency of Pre-boilover Burning of a Slick of Oil on Water

The burning rate of a slick of oil on a water bed is calculated by a simple expression derived from a one-dimensional heat conduction equation. Heat feedback from the flame to the surface is assumed to be a constant fraction of the total energy released by the combustion reaction. The constant fraction (χ) is named the burning efficiency and represents an important tool in assessing the potential of in situ burning as a counter-measure to an oil-spill. The total heat release, as a function of the pool diameter, is obtained from an existing correlation. It is assumed that radiative heat is absorbed close to the fuel surface, that conduction is the dominant mode of heat transfer in the liquid phase and that the fuel boiling temperature remains constant. By matching the characteristic thermal penetration length scale for the fuel/water system and an equivalent single layer system, a combined thermal diffusivity can be calculated and used to obtain an analytical solution for the burning rate. Theoretical expressions were correlated with crude oil and heating oil, for a number of pool diameters and initial fuel layer thickness. Experiments were also conducted with emulsified and weathered crude oil. The simple analytical expression describes well the effects of pool diameter and initial fuel layer thickness permitting a better observation of the effects of weathering, emulsification and net heat feedback to the fuel surface. Experiments showed that only a small fraction of the heat released by the flame is retained by the fuel layer and water bed (of the order of 1%). The effect of weathering on the burning rate decreases with the weathering period and that emulsification results in a linear decrease of the burning rate with water content.     

Calculation of carbon balances for evaluation of the biodegradability of polymers

Establishing carbon balances has been proven to be an applicable and powerful tool in testing biodegradability of polymers. In controlled degradation tests at a 4-L scale with the model polymer poly(-hydroxybutyrate) (PHB), it was shown that the degree of degradation could not be determined with satisfactory accuracy from CO₂ release alone. Instead, the course of degradation was characterized by means of establishing carbon balances for the degradation of PHB withAcidovorax facilis and a mixed culture derived from compost. Different analytical methods for determining the different carbon fractions were adapted to the particular test conditions and compared. Quantitative determination of biomass and residual polymer were the main problems in establishing carbon balances. Amounts of biomass derived from protein measurements depend strongly on assumptions of the protein content of the biomass. Selective oxidation of biomass with hypochlorite was used as alternative, but here problems arose from insoluble metabolic products. Determination of soluble components with the method of chemical oxygen demand (COD) also includes empirical assumptions but seems acceptable if the dissolved carbon fraction is in the range of some 10% total carbon. Results confirm both analytical assays and theoretical approaches, in ending up at values very close to 100%, within an acceptable standard deviation range under test conditions comparable to standard test practice.Paper presented at the Bio/Environmentally Degradable Polymer Society—Third National Meeting, June 6–8, 1994, Boston, Massachusetts.     

富拉尔基发电总厂200MW机组除尘器改造

对富拉尔基发电总厂5号炉的设计条件进行了分析，针对燃用低硫煤，飞灰比电阻高，场地较小，除尘效率要求高的情况，在电除尘器的设计上采取有效措施，达到了排放要求。     

Review of the kinetics of alkaline degradation of cellulose in view of its relevance for safety assessment of radioactive waste repositories

The degradation of cellulose (a substantial component of low- and intermediate-level radioactive waste) under alkaline conditions occurs via two main processes: a peeling-off reaction and a basecatalyzed cleavage of glycosidic bonds (hydrolysis). Both processes show pseudo-first-order kinetics. At ambient temperature, the peeling-off process is the dominant degradation mechanism, resulting in the formation of mainly isosaccharinic acid. The degradation depends strongly on the degree of polymerization (DP) and on the number of reducing end groups present in cellulose. Beyond pH 12.5, the OH^- concentration has only a minor effect on the degradation rate. It was estimated that under repository conditions (alkaline environment, pH 13.3-12.5) about 10% of the cellulosic materials (average DP = 1000-2000) will degrade in the first stage (up to 10⁵ years) by the peeling-off reaction and will cause an ingrowth of isosaccharinic acid in the interstitial cement pore water. In the second stage (10⁵-10⁶ years), alkaline hydrolysis will control the further degradation of the cellulose. The potential role of microorganisms in the degradation of cellulose under alkaline conditions could not be evaluated. Proper assessment of the effect of cellulose degradation on the mobilization of radionuclides basically requires knowing the concentration of isosaccharinic acid in the pore water. This concentration, however, depends on several factors such as the stability of ISA under alkaline conditions, sorption of ISA on cement, formation of sparingly soluble ISA-salts, etc. A discussion of all the relevant processes involved, however, is far beyond the scope of the presented overview.     

Study of Aging Characteristics of Ternary Blends of Polyethylenes—II

Six film samples of low-density polypropylene (LDPE)/linear LDPE (LLDPE)/high-density polypropylene (HDPE) with varying ratios of LDPE (20–45 ... wt%) and LLDPE (25–50 wt%) having a fixed amount of HDPE at 30 wt% were prepared by blown film extrusion technique. The samples were aged at four different temperatures, 55°, 70°, 85°, and 100°C, for four different time periods in the interval of between 150 hours and up to 600 hours. The change in the structure of various constituents and the formation of various oxygenated (peroxy and hydroperoxy) and unsaturated groups during thermo-oxidative degradation was discussed by infrared spectroscopy. The visiosity-average molecular weight was found to have decreased slowly in the initial aging hours and temperatures, whereas it decreased by 10% with its previous value tensile strength that is, 100°C when aged for 600 hours. The tensile strength of the sample first increased by 67% at 55°C and 89% at 70°C up to 450 hours, whereas the values increased by 52.5% at 85°C and 33.9% at 100°C when aged for 150 hours and then decreased. The percentage elongation at break increased by 2.7% at 55°C and 10.7% at 70°C for 150 and 300 hours of aging, respectively, whereas the percentage decreased when aged at 85°C and 100°C for up to 600 hours of aging. The values of gel content (percent) increased and initial degradation temperature decreased with aging time and temperature.     

Selection of adsorbents for treatment of leachate: batch studies of simultaneous adsorption of heavy metals

The simultaneous adsorption of copper (Cu), cadmium (Cd), nickel (Ni), and lead (Pb) ions from spiked deionized water and spiked leachate onto natural materials (peat A and B), by-product or waste materials (carbon-containing ash, paper pellets, pine bark, and semi-coke), and synthetic materials (based on urea-formaldehyde resins, called blue and red adsorbents) or mixtures thereof was investigated. The adsorbents that gave the highest metal removal efficiencies were peat A, a mixture of peat B and carbon-containing ash, and a mixture of peat A and blue. At an initial concentration of 5 mg/l for each metal, the removal of each species of metal ion from spiked water and spiked leachate solutions was very good (>90%) and good (>75%), respectively. When the initial concentration of each metal in the solutions was twenty times higher (100 mg/l), there was a noticeable decrease in the removal efficiency of Cu²⁺, Cd²⁺, and Ni²⁺, but not of Pb²⁺. Langmuir monolayer adsorption capacities, q_m, on peat A were found to be 0.57, 0.37, and 0.36 mmol/g for Pb²⁺, Cd²⁺, and Ni²⁺, respectively. The order of metal adsorption capacity on peat A was the same in the case of competitive multimetal adsorption conditions as it was for single-element adsorption, namely Pb²⁺ > Cd²⁺ ≥ Ni²⁺. The results show that peat alone (an inexpensive adsorbent) is a good adsorbent for heavy metal ions.     

袋式除尘器气流分布数值计算研究

采用结构化/非结构化混合网格技术、多孔介质模型及k-ε两方程湍流模型,对某袋式除尘器及进出口管道内的气体流场进行了数值计算.计算结果表明,合理布置导流板后,袋式除尘器两箱体流量偏差为1.8％;除尘器下游滤袋单元处理气量偏大,中游滤袋单元处理气量较小,最大流量与最小流量偏差为22.3％；靠近除尘器进口处灰斗内存在气流回流特性,易造成粉尘的二次附着现象.     

Effect of Degree of Substitution of Octenyl Succinate Starch on Enzymatic Degradation

Octenyl succinate starch of degree of substitution (ds) 0.03, 0.07, and 0.11 was synthesized in an aqueous medium. These compounds were then tested for the susceptibility to enzymatic degradation. The multiple-enzyme regime of -amylase, amyloglucosidase, and pullulanase was chosen for the evaluation. This combination of enzymes had been proven to degrade 99.5% of unmodified starch to glucose and hence was chosen for this study. It was found that even small amounts of subsituent caused a considerable decrease in the extent of degradation. The net extent of degradation decreased with increasing ds. Surprisingly, the amount of glucose from all three substituted substrates was quite similar, suggesting the effect small amounts of subtituent had on the enzymatic activity.     

Kinetics of Hydrolytic Degradation of PLA

The chemical recycling of poly(lactic acid) (PLA) to its monomer is crucial to reduce both the consumption of renewable resources for the monomer synthesis and the environmental impact related to its production and disposal. In particular, the production of lactic acid from PLA wastes, rather than from virgin raw materials, it is also possible to achieve considerable primary energy savings. The focus of this work is to analyse deeply the PLA hydrolytic decomposition by means of a kinetic model based on two reactions mechanism. To this end, new experimental data have been gathered in order to investigate a wider temperature range (from 140 to 180 °C) and to extend the water/PLA ratio up to 50 % of PLA by weight. The reported results clearly highlight that more than 95 % of PLA is hydrolyzed to water-soluble lactic acid within 120 min, when it is hydrolyzed within 160–180 °C. Furthermore, the kinetic constant is highly influenced by reaction temperature. The proposed “two reactions” kinetic mechanism complies satisfactorily with the experimental data under analysis.     

Effects of temperature on the release of nutrient elements of solid organic materials under conditions of oversaturation

The effects of temperature on the release of chemical components of six solid organic materials under conditions of oversaturation were investigated in this paper. The six materials were peat moss (PM), weathered coals (WC), charred rice husks (CRH), sawdust (Sd), turfgrass clippings (TC), and chicken manure (CM). Significant differences were observed in the available nitrogen and phosphorus content of the aqueous extracts of organic materials at different temperatures. The available nitrogen content in aqueous extracts of PM and WC at 25 °C was higher than that registered at 15 °C and 35 °C. Available nitrogen content in the aqueous extracts of CRH, Sd, TC, and WC at 35 °C was higher than at 15 °C and 25 °C. The available phosphorus content in the aqueous extracts of organic materials at 35 °C was higher than that available at 15 °C and 25 °C, with the exception of Sd. In addition, the release of available phosphorus in the aqueous solution of organic materials at different temperatures varied constantly for 108 h. The release of potassium (K⁺) and sodium (Na⁺) ions in the aqueous extracts of organic materials was basically steady over time, with the exception of CM. High temperature (35 °C) may significantly hasten the release of K⁺ from organic substrates (except for WC) with low temperatures significantly inhibiting release of K⁺ in Sd and CRH. High temperatures (35 °C) might significantly facilitate the release of Na⁺ in CM and TC. However, no significant differences were manifested in the release of Na⁺ from organic substrates at different temperatures, with the exception of CM and TC. Moreover, no significant differences were observed in the release of calcium, magnesium and iron ions with time, nor were there any significant differences in the contents of iron ions in the aqueous extracts of organic materials at different temperatures. The results indicate that multiple mediums should be pretreated in water for a week before being used for planting. They should be used when all mineral elements of organic materials are steady and ignoring the effect of organic mediums.