废硫酸回收利用技术探讨

硫酸是化工与冶金等行业生产常用的原料,但是受其特征影响,在生产过程中经常会产生大量的稀硫酸,如果直接将其排放不但会造成环境污染,同时还会产生巨大的浪费。因此以提高生产综合效益为目的,应采取有效的措施对废酸进行回收利用,降低硫酸的浪费。本文分析了新型废酸回收工艺的特点,并针对几种常用回收工艺的应用进行了分析。     

浓硫酸乙炔净化工艺改造小结

针对10.4万吨/年1,4-丁二醇(BDO)装置硫酸净化乙炔工艺存在废酸储罐温度高、硫酸单耗高等问题进行技改,并对改造前后的运行效果进行对比。改造后废酸储罐温度明显降低,硫酸单耗也有明显降低。     

双酚A生产技术进展

双酚A（Bisphenol A，简称BPA），是一种重要有机原料。工业BPA生产采用苯酚和丙酮在酸性催化剂存在下的缩合反应。按照所用不同催化剂，可分为硫酸法、氯化氢（盐酸）法和离子交换树脂法3种。其中硫酸法以75％～80％硫酸为催化剂，甲苯或氯苯为有机溶剂，疏基乙酸为助催化剂，在反应温度35～40℃下，BPA的收率为82％～86％。该法选择性差，生成杂质多达40余种，且分离困难，因而BPA质量较差，加上形成的废酸和含酸废水对环境造成较大污染，所以发达国家在20世纪60年代起已逐步淘汰该工艺。     

硫酸法钛白粉的清洁生产

当前工业生产需要注意经济和环境效益的有机融合。硫酸法钛白生产工艺存在着严重的环境污染,在该工艺过程中会产生较多的废气、废酸、废水、废渣。要对这种方法进行分析,提出有效的对策来应对污染问题。文章围绕着硫酸法钛白粉清洁生产进行分析,目的是实现硫酸法钛白粉工艺的可持续绿色化生产。     

从糖精废料中回收糖精

糖精的学名为邻磺酰苯酰亚胺（C），白色结晶粉末，用于制备糖精纳，主要用于食品添加剂，在糖精生产过程中，排放大量的废液，尤其在糖精置换工段产生的邻磺酰氯苯甲酸甲酯（a)进入含铜废酸中一起排放下水道，为了回收利用，用泵把废酸打入储罐内，先实施生产铜粉及邻氨基苯甲酸，能获得显著的经济效益，然后再利用废酸内的邻磺酰氯苯甲酸甲酯制取不溶性的糖精，该工艺已经中试成功，并生产1．5t不溶性糖精，创造性糖精，创造可观的经济效益，减少对环境的污染，具有良好的社会效益。     

叶丝加料工艺连批生产模式的设计与应用

为解决规格牌号集中生产时,每批断料间隔时间较长,造成批次料头料尾增加,单箱耗丝居高不下等问题,分析烟草叶丝加料工艺,提出基于叶丝加料工艺的连批生产模式。在保证同牌号的基础上,将批次的运行和设备的启停分离,计量统计也不能影响单批次的质量分析。结果证明:连批生产模式能够适应生产需要,每天可节省1 h时间,出丝率提高0.56%,过程质量更加稳定,能耗降低明显,全年节省500余万元。     

TDI生产硝化废酸浓缩技术研究

基于TDI生产硝化单元下,大量硝化废酸的产出不仅对生态环境造成了一定污染,同时也使得这一生产的综合效益大大降低。因此,对于相应的生产企业而言,要想确保实现自身的可持续发展,就要求在进行TDI生产的过程中,针对硝化废酸的产生落实相应的浓缩回收技术,以从根本上提升自身的经济效益并实现对生态环境的保护。本文针对TDI生产硝化废酸浓缩技术进行了研究与探讨,以供参考。     

导向筛板在甲醇-水蒸馏中的应用

通过对聚乙烯醇生产中聚合三塔和回收三塔的分析及计算机模拟 ,发现两塔具备合并的条件。提出采用大通量、高效率、低压降的导向筛板 ,对原聚合三塔进行技术改造。改造后 ,新聚合三塔代替了原来的聚合三塔和回收三塔 ,处理能力提高 60 % ,操作回流比从原来的 4下降为 1 .7,每年节省循环水 88万 t,节约蒸气 1 .2 2万 t,年增经济效益 49.62万元。     

蒸馏法处理废酸水工艺的优化

在糖精钠生产过程中,废酸水处理一直是个难题,蒸馏法处理废酸水可以降低废水治理的难度,以达到绿色环保、综合利用的目标。在蒸馏过程中,回收酸的浓度不稳定,所以需要对各项参数进行优化,以达到最优条件,能够最大程度的处理废酸。通过优化后,蒸馏过程中,温度可以控制在120℃～130℃之间,压力控制在45kpa～50kpa,尽可能的连续生产,回收酸的浓度和产量比较稳定,能够达到处理废酸水的目的。     

浅谈海藻酸钠生产过程中节水问题

通过海藻酸钠生产过程中,冷凝水回用;钙化废水回用;冲平筛水回用,水洗压榨废酸水回用;污水处理站二次水回用工艺改造,对原有的生产工艺进行一系列的节水减排技术改造,达到节水、节能和减排的目的,同时降低了生产成本,提高企业的经济效益和社会效益,保护了生态环境。     

A Review of: “PROFITABILITY AND ECONOMIC CHOICE” by Paul H. Jeynes The Iowa State University Press 1968 622 pp. $13.50

Semisolid die casting (SSDC) is a newly developed technology to improve the quality of products and to reduce the costs of liquid die casting process. We assessed the gas-induced semisolid process (GISS), which generates a semisolid metal for die casting, in this comparison of the costs per unit between a traditional liquid die casting process and the semisolid die casting process. A process-based costing model (PBCM) was created to estimate the production costs. In principle, the PBCM consists of three submodels: process model, operation model, and financial model. This study indicates that three main factors, namely cycle time, rate of waste, and die life, affected the unit production costs. The production cost estimates decreased by approximately 13% when the process was switched from a liquid to a semisolid one.     

尿磷复合肥的研制

所研究的以尿素为氮源、磷矿粉为磷源生产复合肥料的新方法 ,是用硫酸与尿素作用生成硫酸尿 ,然后再与磷矿粉反应 ,经熟化 ,加入氯化钾 (或硫酸钾 )和微量元素 ,造粒、烘干 ,制得中等浓度的专用复合肥。通过实验研究了尿素与硫酸的配比 ,磷矿粉加入时的温度 ,熟化时间对有效磷的影响等工艺条件 ,从而确定了适宜的工艺参数。     

服装工艺模板结构设计原理与制作

服装模板缝制技术目前在服装生产流程有着比较重要的作用,其模板工艺的成败直接关系到产品质量的整体水平,传统的车工工艺需要较长的时间在实践中获得技艺的提升,工艺模板对于传统的缝制工艺是一种创新和改进。可以起到节约成本、提高生产效率、提高产品质量的作用。     

蒽醌废酸生产碱式氯化铝的研究

以苯酐法生产蒽醌时所产生的含氯化铝的废盐酸为原料 ,采用中和法制备碱式氯化铝。通过最优化实验确定了生产的最佳工艺条件为 p H=2 .3～ 2 .5,反应温度 60～ 70℃ ,反应时间 90 min,熟化时间 4～ 6d,反应收率可达 61 % ,产品符合化工部标准 ( HB/T2 677-95) ,可进行工业化生产 ,同时对企业的废物再利用提供了新途径。     

3-羟甲基四氢呋喃的合成研究

3-羟甲基四氢呋喃是合成第3代烟碱类杀虫剂呋虫胺和核苷类抗病毒药物喷昔洛韦的关键中间体,但长期以来由于使用大量金属硼氢化物造成生产成本高、安全风险高、废物多等缺点。以γ-丁内酯为原料,经Aldol缩合、硼氢化钠还原两步反应得到3-羟甲基四氢呋喃,总收率为51.9%,该法中间体α-羟甲基-γ-丁内酯只有一个内酯羰基需还原,原料γ-丁内酯和甲醛价廉易得,整个工艺路线适于工业化。     

抽油机双功率电机在安塞油田应用的节能分析

在油田企业,机械采油电力驱动装备俱为电机,约占总耗电量的80％。在实际生产中,很多抽油机电机处于轻载、低效、高耗的运行状态,电能浪费严重。因此,电机节能降耗是解决油田节电降耗、降低开采成本的主要方向。通过分析抽油机光杆功率与电机额定功率的理论关系,结合2011年安塞油田引进安装双功率电机的现场应用效果,阐述其工作原理和技术指标,并根据现场监测得到电能参数进行客观、准确的分析评价。     

基于单片机的节水型净水机设计制作

为解决复合型净水机排放废水造成的水资源浪费、滤芯表面杂质沉积造成的净水效果差等问题,设计了节水型净水系统专用的控制系统,包括单片机硬件电路和软件开发流程。单片机硬件电路的设计主要有逻辑电路、扩展输入输出接口、掉电检测、共享中断等,软件开发使用C语言,软硬件结合可以让节水型净水系统相关器件协调控制。运行结果表明,所设计的净水系统可实现制取纯水、回收废水、冲洗滤芯等功能,并且运转正常。节水型净水系统实现了节约用水、延长滤芯使用寿命的设计目标,可为用户节省使用成本,使回收的废水得到合理利用,还可为净水机产业的绿色发展提供设计参考。     

Production lot sizing with a secondary outsourcing facility

An extended economic production quantity (EPQ) model under stochastic demand is investigated in this paper, where a fixed lot sizing policy is implemented to reduce the complexity of production planning and inventory control, and outsourcing with a secondary facility is used to supplement the lot sizing policy and to cope with the random demand. The considered cost includes: setup cost for the batch production, inventory carrying cost, backorder cost when the demand cannot be met immediately during the production period, and outsourcing cost when the total demand is greater than the lot size in one replenishment cycle. Under some mild conditions, the expected cost per unit time can be shown to be convex. Extensive computational tests have illustrated that the average cost reduction of the proposed model is significant when compared with that of the classical lot sizing policy. Significant cost savings can be achieved by deploying the production lot sizing policy with an outsourcing strategy when the mean demand rate is high.     

Review: Consumption-stage food waste reduction interventions – What works and how to design better interventions

Food waste prevention has become an issue of international concern, with Sustainable Development Goal 12.3 aiming to halve per capita global food waste at the retail and consumer levels by 2030. However there is no review that has considered the effectiveness of interventions aimed at preventing food waste in the consumption stages of the food system. This significant gap, if filled, could help support those working to reduce food waste in the developed world, providing knowledge of what interventions are specifically effective at preventing food waste.This paper fills this gap, identifying and summarizing food-waste prevention interventions at the consumption/consumer stage of the supply chain via a rapid review of global academic literature from 2006 to 2017.We identify 17 applied interventions that claim to have achieved food waste reductions. Of these, 13 quantified food waste reductions. Interventions that changed the size or type of plates were shown to be effective (up to 57% food waste reduction) in hospitality environments. Changing nutritional guidelines in schools were reported to reduce vegetable waste by up to 28%, indicating that healthy diets can be part of food waste reduction strategies. Information campaigns were also shown to be effective with up to 28% food waste reduction in a small sample size intervention.Cooking classes, fridge cameras, food sharing apps, advertising and information sharing were all reported as being effective but with little or no robust evidence provided. This is worrying as all these methods are now being proposed as approaches to reduce food waste and, except for a few studies, there is no reproducible quantified evidence to assure credibility or success. To strengthen current results, a greater number of longitudinal and larger sample size intervention studies are required. To inform future intervention studies, this paper proposes a standardised guideline, which consists of: (1) intervention design; (2) monitoring and measurement; (3) moderation and mediation; (4) reporting; (5) systemic effects.Given the importance of food-waste reduction, the findings of this review highlight a significant evidence gap, meaning that it is difficult to make evidence-based decisions to prevent or reduce consumption-stage food waste in a cost-effective manner.     

INNOVATION AND COMPETITIVE PRESSURE*

I analyze the effects of competition on process innovation and product introduction and obtain robust results that hold for a range of market structures and competition modes. It is found that increasing the number of firms tends to decrease cost reduction expenditure per firm, whereas increasing the degree of product substitutability, with or without free entry, increases it—provided that the average demand for product varieties does not shrink. Increasing market size increases cost reduction expenditure per firm and has ambiguous effects on the number of varieties offered, while decreasing the cost of entry increases the number of entrants and varieties but reduces cost reduction expenditure per variety. The results are extended to other measures of competitive pressure and to investment in product quality. The framework and results shed light on empirical strategies to assess the impact of competition on innovation.