磷石膏处置标准与磷石膏堆场处置设想

比照国家固体废物处置标准,依据磷石膏性状指标,逐级给出了磷石膏经济、合理的处置方法.归纳为大型磷石膏堆场设计方法判别程式.对Ⅱ类磷石膏堆场的防渗,提出了处置设想.     

磷石膏的综合利用与应重视的问题

磷石膏是湿法磷酸生产过程中的副产物,磷石膏的综合利用对于提高磷复肥生产厂家的经济效益及其周边环境的治理具有不可估量的潜在价值。对磷石膏的开发利用作了详细的论述,并且指出了在磷石膏的开发利用过程中应该重视的五大问题。     

树立磷石膏是产品的理念，为磷石膏资源化利用奠定基础

磷石膏综合利用是磷肥行业节能减排工作的重点和难点.树立磷石膏是产品的理念;通过对磷石膏杂质特性的分析,了解对其应用性能的影响,确定磷石膏预处理工艺路线的合理途径,为磷石膏资源化利用奠定基础.     

一种新型磷石膏烘干机

一种新型磷石膏烘干机吕天宝（山东鲁北化工总厂２５１９０７）随着我国高浓度磷复肥工业的发展，磷石膏的利用日益受到重视。用磷石膏制造硫酸与水泥是磷复肥厂解决磷石膏污染环境、占用土地行之有效的办法，并实现硫的良性循环，其综合效益显著。目前建成和在建的生产装...     

两步法由磷石膏和氯化钾生产硫酸钾的试验研究

介绍以磷石膏、碳酸氢铵和氯化钾为原料，两步法制取硫酸钾并联产氮、钾或氮、磷、钾复合肥料这一新工艺的实验室研究结果。该新工艺为磷石膏的合理利用和硫酸钾的生产开辟了一条新途径     

过磷酸钙生产中掺入磷石膏的方法

介绍在过磷酸钙生产中,综合利用饲料级磷酸氢钙配套的磷酸装置副产磷石膏的几种方法.将磷石膏直接掺入过磷酸钙一级品中,或者直接掺入过磷酸钙的鲜肥中,不会影响产品的质量、转化率、物性.将磷石膏与磷矿粉制浆后生产过磷酸钙,其产品转化率有所降低,而且会增加球磨机和混合器的生产负荷,降低产量.     

二水法改二水-半水法生产湿法磷酸的技术改造

通过提高磷酸浓度和降低磷石膏中P2O5含量,达到降低浓缩能耗和提高磷石膏质量,满足水泥生产的要求.介绍该厂将二水法生产磷酸工艺改造为二水一半水法工艺的流程、新增设备、工艺指标及技术要点.技改后,磷酸w(P2O5)由22%提高到35%,磷石膏中W(P2O5)由1.5%下降到0.2%以下,磷石膏中的W(H2O结晶)由14%～16%下降到4%～8%,每年节煤约1.5万t,综合新增效益l 786万元.     

磷石膏制硫酸铵的模型试验研究

提出了原料磷石膏不经过净制的转化制硫铵流程，并通过模型试验研究了碳酸氢铵用量、料浆ｐＨ值、转化温度及转化时间对碳酸钙过滤强度、硫的转化率和氮损失的影响。试验得出的最佳工艺条件和主要技术参数，可供磷石膏转化制硫酸铵工业生产参考。     

高钾钠磷石膏生产纸面石膏板工艺控制

用含钾钠高的磷石膏生产纸面石膏板时出现不粘纸现象.通过采用自主开发的抑制剂,使钾钠生成溶解度小的难溶盐;并选用合适的生产工艺,调节一次脱水、二次脱水温度,抑制剂加量等有效的控制方法,实现了用含钾钠高的磷石膏生产出合格纸面石膏板.     

如何降低湿法磷酸副产磷石膏的总磷损失

广西鹿寨化肥有限公司磷酸厂磷酸装置采用二水湿法工艺生产磷酸.现将如何降低磷石膏不溶性磷、水溶性磷的措施分别介绍如下.     

Preparation of high-performance lightweight materials based on the phosphogypsum-inorganic material system

Phosphogypsum (PG) is a typical solid waste of the phosphorus chemical industry, The existing stock in the world has exceeded 5.6 billion tons, and its resource utilization rate is less than 30%. In order to improve the resource utilization rate of PG, this paper explores the prospect of PG and inorganic material composite systems in the large-scale absorption and utilization of PG, inorganic materials mainly include S95 slag powder(S95), fly ash (FA), Quicklime (QL) and ordinary Portland cement (OPC). The pretreatment of phosphogypsum is mainly to calcine at high temperature, the gradient of an H₂O₂ foaming agent affected the mechanical characteristics of a binary concrete system based on PG was explored based on the optimum mix ratio of PG and inorganic substance to formed four different binary concrete systems. The experimental results show that in the binary concrete system, when the addition amount of S95, FA, QL, and OPC was 20%, 13%, 6%, and 26%, respectively, they show significant comprehensive performance, OPC has the most significant effect. The optimum addition of H₂O₂ to the four binary concrete systems is 0.2%, 0.4%, 0.6%, and 0.6%, respectively. The mechanical properties of the system are less affected by the foaming agent, and found an increase in its flexural strength from 4.5 MPa to 4.75 MPa, softening coefficient from 0.88 to 0.99, and compressive strength from 16.3 MPa to 17.3 MPa. This research greatly reduces the difficulty of phosphogypsum resource treatment and provides basic theoretical support for a large amount of phosphogypsum consumption.     

试论磷铵配套磷石膏制硫酸联产水泥装置规模

从物料平衡角度以及企业改造的难易程度,论述了３０ｋｔ／ａ磷铵配套磷石膏制４０ｋｔ／ａ硫酸、６０ｋｔ／ａ水泥（即“３、４、６”）装置技术改造后,装置规模应为６０ｋｔ／ａ磷铵、６０ｋｔ／ａ硫酸、７０ｋｔ／ａ水泥（即“６、６、７”）。     

Scandinavian experiences with indoor air pollution

The building illness syndrome (BIS) with complaints about dryness and irritation of the mucous membranes of the eyes, nose and throat, and headaches is very common in Scandinavian buildings. The causes for BIS may be psychosocial, biological, physical or chemical factors in the indoor environment. Of these the chemical factors are considered to be the most important. BIS can be caused by formaldehyde, but the main sources of this emission are now controlled in the Scandinavian countries. As BIS complaints still are common, organic gases and vapors are considered to be the most important cause of BIS today. These gases and vapors are emitted from many building materials, and mixtures of these have been shown to be irritating in concentrations about 5 mg m-3, a concentration which is often found in new buildings. It is still an unsolved problem if BIS is due to the mixture of the organic gases and vapors themselves, or decomposition products in low concentrations, as for example peroxyacetyl nitrates known from outdoor air pollution. Irrespective of the cause, the rational approach would be a reduction of the emissions of organic gases and vapors from building materials or an increase of ventilation rates. The latter solution is not desirable due to the economic burden and to the need for energy conservation. We therefore suggest that building materials should be tested for emission of pollutants, so that materials emitting high concentrations of toxic substances can be identified and replaced by materials emitting less toxic substances and with emission of a lower rate.     

Practical Limitations of Tableting Indices

The purpose of this study was to utilize tableting indices to distinguish between materials with varying degrees of compactibility by establishing a quantitative relationship between indices and compactibility. Compactibility in this study is restricted to tablet strength and friability alone. Nine mixtures with varying degrees of compactibility were tableted and the tensile strength and friability of the tablets were determined. The tableting indices of these mixtures were determined using an Instron® Universal testing machine. An artificial neural network program was used to establish a quantitative relationship between indices and tablet strength and friability. Six new powders were used to validate the models describing the relationship between indices and tablet strength and friability. These powders were compressed into tablets and their strength and friability were determined. Their indices were also determined. The established models were used to predict tablet strength and friability from index values. The predicted values were compared with the experimentally determined values. There was little correlation between the predicted and experimentally determined values for tablet strength and friability. It was also found that materials or mixtures having almost similar indices had remarkably different compactibilites. It was concluded that models created to predict compactibility using one set of materials may not be able to successfully predict the compactibility of a new material. This calls into question the practicality of indices.     

Practical limitations of tableting indices.

The purpose of this study was to utilize tableting indices to distinguish between materials with varying degrees of compactibility by establishing a quantitative relationship between indices and compactibility. Compactibility in this study is restricted to tablet strength and friability alone. Nine mixtures with varying degrees of compactibility were tableted and the tensile strength and friability of the tablets were determined. The tableting indices of these mixtures were determined using an Instron Universal testing machine. An artificial neural network program was used to establish a quantitative relationship between indices and tablet strength and friability. Six new powders were used to validate the models describing the relationship between indices and tablet strength and friability. These powders were compressed into tablets and their strength and friability were determined. Their indices were also determined. The established models were used to predict tablet strength and friability from index values. The predicted values were compared with the experimentally determined values. There was little correlation between the predicted and experimentally determined values for tablet strength and friability. It was also found that materials or mixtures having almost similar indices had remarkably different compactibilities. It was concluded that models created to predict compactibility using one set of materials may not be able to successfully predict the compactibility of a new material. This calls into question the practicality of indices.     

Virus-based nanocarriers for drug delivery

New nanocarrier platforms based on natural biological building blocks offer great promises in revolutionalizing medicine. The usage of specific protein cage structures: virus-like particles (VLPs) for drug packaging and targetted delivery is summarized here. Versatile chemical and genetic modifications on the outer surfaces and inner cavities of VLPs facilitate the preparation of new materials that could meet the biocompatibility, solubility and high uptake efficiency requirements for drug delivery. A full evaluation on the toxicity, bio-distribution and immunology of these materials are envisaged to boost their application potentials.     

Carbon nanotubes as optical biomedical sensors

Biosensors are important tools in biomedical research. Moreover, they are becoming an essential part of modern healthcare. In the future, biosensor development will become even more crucial due to the demand for personalized-medicine, point-of care devices and cheaper diagnostic tools. Substantial advances in sensor technology are often fueled by the advent of new materials. Therefore, nanomaterials have motivated a large body of research and such materials have been implemented into biosensor devices. Among these new materials carbon nanotubes (CNTs) are especially promising building blocks for biosensors due to their unique electronic and optical properties. Carbon nanotubes are rolled-up cylinders of carbon monolayers (graphene). They can be chemically modified in such a way that biologically relevant molecules can be detected with high sensitivity and selectivity. In this review article we will discuss how carbon nanotubes can be used to create biosensors. We review the latest advancements of optical carbon nanotube based biosensors with a special focus on near-infrared (NIR)-fluorescence, Raman-scattering and fluorescence quenching.