Using thermal analysis with kinetic calculation method to assess the thermal stability of azo compound on construction materials

The application of construction polymers in engineering and alternative materials has always occupied a place in the market. In the production process of polymer resins, initiators can be used to lower the polymerization reaction energy threshold, which can improve reaction efficiency and reduce energy loss. However, as a commonly used energetic substance in the polymerization process, azos have caused related process hazards due to their exothermic characteristics. Because of this, it is essential to examine and analyze the thermal hazard characteristics of emerging azo substances, such as 2-cyanopropan-2-imemicarbazide (CABN). Although previous literature performs the calculation on related thermal hazard parameters of CABN, there is still exists a void for discussion in estimating the reaction model to avoid analogous hazards and enhance the existing thermal analysis. Based on the past literature, the reaction model is improved with thermogravimetric analysis as evidence. The revised thermal hazard parameters are calculated as the basis of control and mitigation measures, the kinetic model is used to estimate the modified safety parameters, and in the judgment of the runaway reaction, the critical temperature of the runaway is found by analyzing the influence of slight changes in ambient temperature on the reaction temperature. The results show that the critical temperature that causes CABN to enter the runaway reaction is delayed, and the hazard is lower than in the storage situation. Therefore, the thermal hazard to CABN mainly focuses on the safety environment and measures during storage.     

浅谈污水处理过程中配制聚合物溶液粘度研究

45℃反应30 d内,120 mg/L稳定剂稳定处理后中十二站污水和未经处理的北1-J3-P49井口采出污水配制的聚合物溶液的粘度保留率89.2～107%,并随反应时间的延长粘度保留率值有增高的趋势。添加120 mg/L稳定剂聚驱具有代表性北1-Ⅱ污水站污水配制的1200 mg/L聚合物溶液,5～1000 S-1上、下行剪切速率条件下的抗剪切性能优于污水直接的聚合物溶液,且随反应时间的延长,添加稳定剂污水配制的聚合物溶液抗剪切性能相对污水直接配制的聚合物溶液更加显著,稳定剂稳定聚合物溶液效果良好。仅添加120 mg/L稳定剂污水配制的聚合物溶液,30 d的粘度保留率89.2～107%,稳定剂稳定污水配制聚合物溶液的效果良好,且5～1000 S-1上、下行剪切速率条件下的抗剪切性优于污水直接的聚合物溶液,可以推测添加稳定剂污水配制的聚合物溶液的实际调驱效果好于污水直接配制的聚合物驱替液。     

A New Respirometric Test Simulating Soil Burial Conditions for the Evaluation of Polymer Biodegradation

A new convenient and reliable method is described for assessing the biodegradation properties of polymeric materials under simulated soil burial conditions, which makes it possible to test with nutrient-rich soils. This method consists of the utilization of a minimum amount of a soil layer, in which the samples to be tested are set in close contact, sandwiched between two layers of perlite, a natural porous aluminosilicate. The biodegradation level is monitored by determining the carbon dioxide evolution derived from the test samples. The limited amount of soil used limits carbon dioxide evolution from the blanks, due to the corresponding limited overall amount of soil carbon. This experimental setup allows for an extremely satisfactory level of confidence in the analytical results, permitting a wider variety of soil types to be tested.     

用DWZ接触氧化处理工艺处理屠宰废水

实行畜禽定点屠宰后，含有大量有机污染物的畜禽屠宰废水的处理问题急需解决，经浙江省海宁市某畜禽屠宰厂运行证实，采用DWZ接触氧化处理工艺，具有投资少，占地面积小，处理效果好，抗冲击能力强，操作简便，运行费用低等特点，废水经处理后可达到GB8978－1996 Ⅰ级排放标准，得到了社会各界的广泛好评，本文主要介绍了该处理设施的处理工艺，运行特点及优越性，提供一条治理畜禽宰废水的有效途径。     

废铁屑生产聚合硫酸铁实验研究

文章介绍了聚合硫酸铁的制备，并用不同的原料合成了几种聚合硫酸铁产品，讨论了影响产品性能的因素。同时，将它们用于给水处理和污水处理，取得了较为理想的结果。     

Fenton试剂处理油田含聚污水中聚丙烯酰胺的试验研究

通过对我国油田含聚污水污染状况进行分析,提出处理油田含聚污水的关键是去除污水中的聚丙烯酰胺(HPAM).以聚丙烯酰胺污水为处理对象,通过正交试验确定了Fenton试剂各影响因素的影响权重,并深入研究了Fenton试剂中各影响因素的作用机制,同时通过分别试验确定了Fenton试剂处理聚丙烯酰胺污水的最佳操作条件:Fe2 和H2O2浓度分别为400mg/L、1.0mL/L,反应温度40 ℃、反应时间15 min,反应体系的pH为3左右,HPAM的降解率能达到88%以上,COD降解率高达97%.     

Enhanced hydrolytic removal of tylosin in wastewater using polymer-based solid acid catalysts converted from polystyrene

Antibiotic production wastewater usually contains high concentrations of antibiotic residues, which can cause instability and deterioration of biological wastewater treatment units and also domestication and proliferation of antibiotic-resistance bacteria. An effective pretreatment on antibiotics production wastewater is expected to selectively reduce the concentration of antibiotics and decrease the toxicity, rather than mitigate organic and other contaminants before further treatments. In this work, two polymer-based solid acids, PS-S and CPS-S bearing high concentrations of -SOH₃ groups (up to 4.57 mmol/g), were prepared and successfully used for hydrolytic mitigation of 100 mg/L tylosin within 20 min. The co-existence of high concentrations of COD and humic substances did not affect the mitigation of tylosin obviously, while more than 500 mg/L of nitrogenous compounds suppressed the hydrolytic efficiency. Recycle and reuse experiments showed that the solid acids performed well in five cycles after regeneration. Three transformation products (P1, P2 and P3) were identified using UPLC-QTOF-MS/MS. Sugar moieties including mycarse, mycaminose, and mycinose detached and released simultaneously or in order from the 16-member lactone ring through desugarization, which led to a dramatic decrease in antibacterial activity as revealed by cytotoxicity evaluations using S. aureus. Ecotoxicity estimation indicated the acute toxicities of the hydrolyzed products to model species (e.g., fish, daphnid and green algae) were classified as “not harmful”. This work suggested an effective and selective method to pretreat tylosin-contained production wastewater by using polymer-based solid acids. These results will shed light on effective elimination of antibiotics pollution from pharmaceutical industries through strengthening the pretreatments.     

无机高分子混凝剂的发展与应用

讨论了不同类型无机高分子混凝剂的混凝机理、生产及应用，并指出了新型混凝剂的研制方向．     

Sustainable design for automotive products: Dismantling and recycling of end-of-life vehicles

The growth in automotive production has increased the number of end-of-life vehicles (ELVs) annually. The traditional approach ELV processing involves dismantling, shredding, and landfill disposal. The “3R” (i.e., reduce, reuse, and recycle) principle has been increasingly employed in processing ELVs, particularly ELV parts, to promote sustainable development. The first step in processing ELVs is dismantling. However, certain parts of the vehicle are difficult to disassemble and use in practice. The extended producer responsibility policy requires carmakers to contribute in the processing of scrap cars either for their own developmental needs or for social responsibility. The design for dismantling approach can be an effective solution to the existing difficulties in dismantling ELVs. This approach can also provide guidelines in the design of automotive products. This paper illustrates the difficulty of handling polymers in dashboards. The physical properties of polymers prevent easy separation and recycling by using mechanical methods. Thus, dealers have to rely on chemical methods such as pyrolysis. Therefore, car designers should use a single material to benefit dealers. The use of materials for effective end-of-life processing without sacrificing the original performance requirements of the vehicle should be explored.     

Investigation of thermal treatment on selective separation of post consumer plastics prior to froth flotation

Plastics have become the widely used materials because of their advantages, such as cheapness, endurance, lightness, and hygiene. However, they cause waste and soil pollution and they do not easily decompose. Many promising technologies are being investigated for separating mixed thermoplastics, but they are still uneconomical and unreliable. Depending on their surface characteristics, these plastics can be separated from each other by flotation method which is useful mineral processing technique with its low cost and simplicity.The main objective of this study is to investigate the flotation characteristics of PET and PVC and determine the effect of plasticizer reagents on efficient plastic separation. For that purpose, various parameters such as pH, plasticizer concentration, plasticizer type, conditioning temperature and thermal conditioning were investigated. As a result, PET particles were floated with 95.1% purity and 65.3% efficiency while PVC particles were obtained with 98.1% purity and 65.3% efficiency.