Biodegradation of Coir and Sisal Applied in the Automotive Industry

This paper discusses the results of biodegradability tests of natural fibers used by the automotive industry, namely: coir, coir with latex, and sisal. The biodegradation of coir, coir with latex, and of sisal fibers was determined by monitoring the production of carbon dioxide (CO₂) (IBAMA—E.1.1.2, 1988) and fungal growth (DIN 53739, 1984). The contents of total extractives, lignin, holocellulose, ashes, carbon, nitrogen and hydrogen of the fibers under study were determined in order to ascertain their actual content and to understand the results of the biodegradation tests. The production of CO₂ indicated low biodegradation, i.e., about 10% in mass, for all the materials after 45 days of testing; in other words, no material inhibited glucose degradation. However, the percentage of sisal fiber degradation was fourfold higher than that of coir with latex in the same period of aging. The fungal growth test showed a higher growth rate on sisal fibers, followed by coir without latex. In the case of coir with latex, we believe the fungal growth was not intense, because natural latex produces a bactericide or fungicide for its preservation during bleeding [1]. An evaluation of the materials after 90 days of aging tests revealed breaking of the fibers, particularly sisal and coir without latex, indicating fungal attack and biodegradation processes.     

Recent Contributions to the Preparation of Polymers Derived from Renewable Resources

The aim of this paper is to provide an update on the ongoing research of our laboratory in the field of polymeric materials derived from biomass components. The first section deals with the oxypropylation of different vegetable or animal biomass residues and the use of the ensuing polyols in different polyurethane formulations. Thus, foams, elastomers, and membranes were obtained and their properties compared favorably with those of equivalent materials prepared from petroleum-based sources. The second section is devoted to furan copolymers and their use in reversibly crosslinked elastomers via the Diels–Alder reaction and in the field of photosensitive materials. The third section describes novel approaches to the surface modification of cellulosic fibers to be employed in composite materials with polymeric matrices, consisting in the use of organometallics and siloxanes as coupling agents. The final two sections are devoted to a brief outline of the role of lignins and vegetable oils as additives in printing inks, varnishes, and paints.     

Development of Lignin and Nanocellulose Enhanced Bio PU Foams for Automotive Parts

The green rigid polyurethane (PU) foam has been developed with 100 % soy polyol after optimization of formulation ingredients and lignin has been introduced and isocyanate content reduced in the green rigid PU foam. The cellulosic nanofibers have also been successfully incorporated and dispersed in green rigid PU foam to improve the rigidity. The influence of nano cellulose fiber modification (enzymatic treatment, hydrophobic modification with latex) on the foam density, open cell content, foam raise height, water vapor, and mechanical properties of rigid PU foam were studied. The foamed structures were examined using scanning electron microscopy to determine the cell size and shape due to the addition of cellulosic nanofibers. The odor test were performed to evaluate the odor concentration 100 % soyol based PU foam including lignin and nanofiber and compared to 100 % synthetic based polyol PU foam. The experimental results indicated that the compression and impact properties improved due to the modification of nano cellulosic fibers. The odor concentration level of nanofiber reinforced rigid PU foam reduced significantly compared to 100 % PU foam due to the replacing of isocyanate content. It can be said that with an appropriate combination of replacing isocyanate by lignin and addition of nanofiber, rigid PU foam properties could be improved.     

Sustainable Bio-Composites from Renewable Resources: Opportunities and Challenges in the Green Materials World

Sustainability, industrial ecology, eco-efficiency, and green chemistry are guiding the development of the next generation of materials, products, and processes. Biodegradable plastics and bio-based polymer products based on annually renewable agricultural and biomass feedstock can form the basis for a portfolio of sustainable, eco-efficient products that can compete and capture markets currently dominated by products based exclusively on petroleum feedstock. Natural/Biofiber composites (Bio-Composites) are emerging as a viable alternative to glass fiber reinforced composites especially in automotive and building product applications. The combination of biofibers such as kenaf, hemp, flax, jute, henequen, pineapple leaf fiber, and sisal with polymer matrices from both nonrenewable and renewable resources to produce composite materials that are competitive with synthetic composites requires special attention, i.e., biofiber–matrix interface and novel processing. Natural fiber–reinforced polypropylene composites have attained commercial attraction in automotive industries. Natural fiber—polypropylene or natural fiber—polyester composites are not sufficiently eco-friendly because of the petroleum-based source and the nonbiodegradable nature of the polymer matrix. Using natural fibers with polymers based on renewable resources will allow many environmental issues to be solved. By embedding biofibers with renewable resource–based biopolymers such as cellulosic plastics; polylactides; starch plastics; polyhydroxyalkanoates (bacterial polyesters); and soy-based plastics, the so-called green bio-composites are continuously being developed.     

Comparative Biodegradation in Soil Behaviour of two Biodegradable Polymers Based on Renewable Resources

This work presents the last phase of long-term experimental studies on the biodegradation in soil behaviour of polymers destined for agricultural applications. The paper focuses on comparative studies between the biodegradation in soil behaviour of two important biodegradable polymers based on renewable resources: poly(lactic acid) (PLA) versus polyhydroxyalkanoates (PHA). Full-scale experiments were carried out during the period June 2008–January 2009. Different methods of exposure were applied in the case of polyhydroxyalkanoates, simulating the agricultural biodegradable mulching films use and their fate in soil after the end of their useful lifetime. The field results were compared with the results of biodegradation under controlled laboratory conditions simulating biodegradation in soil, using soil from the experimental field. Further, the field results were compared against the results of biodegradation under farm composting conditions.     

Mechanical and Thermal Properties of Biocomposites Based on Polyethylene from Renewable Resources Modified with Ionic Liquids

Journal of Polymers and the Environment - Biocomposites based on polyethylene from renewable resources derived from sugar cane as raw material were modified with phosphonium ionic liquids....     

再生资源行业循环经济水平评估体系研究

基于循环经济发展视角,对再生资源行业进展进行综述,指出当前缺乏系统的再生资源行业评价指标体系。从再生资源企业和再生资源行业两个角度构建再生资源行业发展评价指标体系,以期对再生资源行业从定量的角度进行分析。     

Environmental Assessments in the Oil and Gas Industry

The general public, government regulators, and environmental organizations are increasingly demanding industries to reduce their environmental impacts and report progress. This in turn resulted in numerous requirements for reporting environmental data. Environmental assessments are a useful tool in gathering and documenting this data. The assessments also assist decision makers to quantify impacts of their activities and plan for appropriate mitigation measures. There are different types of environmental assessments, each having specific purpose(s) and addressing specific audience(s). This paper gives an overview of common environmental concerns associated with oil and gas industry and shares insights on types of environmental assessments that are widely used. It discusses general methodologies to define the scope, approach, measurement standards, and reporting. Potential challenges encountered in conducting these assessments in an international arena and under a wide variety of regulatory requirements are addressed. Practical approach in execution of these assessments is described here, and strategy in dealing with the challenges is presented.     

The Effect of Natural Tree Gum and Environmental Condition on the Degradation of a Typical Automotive Clear Coat

In this work the effects of natural gum and its simulated compound (Arabic gum) on an acrylic based clear coat applied on different basecoats were studied. The experiments were conducted at various aging processes to simulate the real outdoor conditions by the aid of different analytical techniques including optical microscopy, scanning electron microscopy, ATR-FTIR spectroscopy, DMTA and micro hardness measurements, by which the chemical and mechanical responses of the system were investigated. Results showed that, Arabic and natural gums, due to their sticky nature in the slurry state, can strongly attach to the clear coat surface and perform a significant stress during the drying process. It was shown that, this stress was responsible for the surface cracks produced by gums, indicating a physical degradation mechanism. However, it was revealed that, biological materials could also affect the clear coat chemically. In addition, different surface cracks produced by gums on the clear coat applied on silver and black basecoats were observed and attributed to their surface chemistry and mechanical properties differences. It was shown that different amounts of aluminum flakes existed in the basecoat layers of silver and black system can effectively influence the curing degree of the clear coats applied on the se systems. This leads to different cross-linking density, toughness and surface chemistries. Therefore, different interactions of clear coats and gums, as well as stress distribution and relaxation behaviors of these two systems were found effective in such degradations. Comparison of the mechanical properties and visual effects of gums on clear coats indicated a more severe degradation under the post aging, due to the greater effect of UV light.     

Wastewater Fines Influence the Adsorption Behavior of Pollutants onto Microplastics

Millions of tons of microplastics (MPs) enter the wastewater collection systems every day and interact with raw sewage. In addition to MPs, varieties of organic and inorganic fines from urban effluents release into the sewer system and provide suitable surfaces for adsorption. To better understand the quantitative assessment of MPs sorption in wastewater and the role of fines, batch reactor experiments were performed using synthetic wastewater solutions containing organic, inorganic, and mixed organic–inorganic fines, and the results compared to a solution without fines. The MPs were two types of clean polypropylene (PP) particles, isotactic (iPP) and atactic (aPP). The results showed in all applied solutions the adsorption of pollutants was higher for the aPP averaging 1.3 mg/g compared with 0.5 mg/g for iPP, indicating that the adsorption varies with the type of polymer and surface properties. Further experiments also revealed a decrease in the sorption values of MPs for solutions containing inorganic fines, measured as the partition coefficient (K_d) and adsorbed concentration at equilibrium (q_e). The result of the measured reference conductivity (к₂₅) of the solutions for the same tests showed similar trends indicating that the magnitude of pollution adsorption onto MPs surfaces is controlled by the surface charge potential of the fine particles. The relationship between the qualitative assessments of ion removal, measured in terms of к₂₅, and their quantitative assessment of adsorption values in terms of K_d in several identical tests, verifying that the conductivity of the solution was modified after adsorption of wastewater constituents onto the MPs.

     

Behavior of PAHs from sewage sludge incinerators in Korea

Although production of sewage sludge increases every year, its proper treatment has only been recently raised as a new issue, as current landfill and ocean dumping arrangements are expected to become increasingly difficult to manage in the future. The Korean Ministry of Environment plans to diversify its processing facilities and expand its processing systems by 2011, with the purpose of processing all sludge produced in Korea. According to this plan, incineration (including incineration of municipal wastes) will process 30% of the entire sewage sludge throughout the country in 2011. This study reviews the characteristics of PAH, which is one of the organic substances found in sewage sludge during the incinerating process. The total amount of PAH produced from sewage sludge incineration was found to be 6.103 mg/kg on average, and investigation performed on 16 PAHs of inlets and outlets of the air control devices at five full-scale incineration facilities showed that concentrations of the PAHs on the inlet and on the outlet ranged from 3.926 to 925.748 microg/m(3) and from 1.153 to 189.449 microg/m(3), respectively. In the case of the incineration facility fed with municipal waste (95%) and sewage sludge (5%), the total of the PAH emissions concentration was higher than that found at the incineration facilities used exclusively to treat sewage. The combustion of waste vinyl and plastics contained in municipal waste fed into the facility might contribute to the high levels of PAHs in the stack gas. However more investigation is needed on the production mechanism of PAHs at different operating conditions of the incineration facilities, such as the types of waste, and other relevant factors.     

以清洁生产理念促进我国钛白粉产业的发展

介绍了我国钛白粉产业的现状,阐述了钛白粉产业清洁生产的重要性,分析了影响我国钛白粉产业可持续发展的问题及原因.指出施行清洁生产对钛白粉产业加快技术进步、调整产业结构、促进产业升级具有重要意义.     

Developing Measures for Assessing the Causality of Safety Culture in a Petrochemical Industry

This paper discusses safety culture in the petrochemical sector and the causes and consequences of safety culture. A sample of 520 responses selected by simple random sampling completed questionnaires for this survey, the return rate was 86.75%. The research instrument comprises four sections: basic information, the safety leadership scale (SLS), the safety climate scale (SCS), and the safety performance scale (SPS). SPSS 12.0, a statistical software package, was used for item analysis, validity analysis, and reliability analysis. Exploratory factor analysis indicated that (1) SLS abstracted three factors such as safety caring, safety controlling, and safety coaching; (2) SCS comprised three factors such as emergency response, safety commitment, and risk perception; and (3) SPS was composed of accident investigation, safety training, safety inspections, and safety motivation. We conclude that the SLS, SCS, and SPS developed in this paper have good construct validity and internal consistency and can serve as the basis for future research.     

改进催化光度法测定水中的微量钒

采用改进催化光度法测定微量钒,即利用微量钒催化溴酸钾氧化甲基紫溶液褪色实现快速测定水中的微量钒。在50mL容量瓶中,在pH为1.6的硫酸加入量0.90mL、0.0100mol/L的溴酸钾溶液加入量4.50mL、2.5×10-4mol/L的甲基紫溶液加入量5.00mL的条件下,聚乙二醇-200作活化剂时,在92℃恒温反应12min,加钒和不加钒溶液的吸光度之差与钒质量浓度呈线性关系。该法的测定波长为580nm,检出限为5.2×10-8g/L,最大相对标准偏差为4.3%,回收率为95.8%~104.0%。该法可用于湖水、化工厂排水中微量钒的直接测定。     

Improved methodology to assess modification and completion of landfill gas management in the aftercare period

Municipal solid waste landfills represent the dominant option for waste disposal in many parts of the world. While some countries have greatly reduced their reliance on landfills, there remain thousands of landfills that require aftercare. The development of cost-effective strategies for landfill aftercare is in society’s interest to protect human health and the environment and to prevent the emergence of landfills with exhausted aftercare funding. The Evaluation of Post-Closure Care (EPCC) methodology is a performance-based approach in which landfill performance is assessed in four modules including leachate, gas, groundwater, and final cover. In the methodology, the objective is to evaluate landfill performance to determine when aftercare monitoring and maintenance can be reduced or possibly eliminated. This study presents an improved gas module for the methodology. While the original version of the module focused narrowly on regulatory requirements for control of methane migration, the improved gas module also considers best available control technology for landfill gas in terms of greenhouse gas emissions, air quality, and emissions of odoriferous compounds. The improved module emphasizes the reduction or elimination of fugitive methane by considering the methane oxidation capacity of the cover system. The module also allows for the installation of biologically active covers or other features designed to enhance methane oxidation. A methane emissions model, CALMIM, was used to assist with an assessment of the methane oxidation capacity of landfill covers.     

Improved understanding of key elements governing the toxicity of energy ash eluates

Ash from incinerated waste consists mainly of a complex mixture of metals and other inorganic elements and should be classified based on its inherent hazardous effects according to EUs Waste Framework Directive. In a previous study, we classified eight eluates from ash materials from Swedish incineration plants, both chemically and ecotoxicologically (using bacteria, algae, crustacean and fish). Based on measured concentrations in the eluates together with literature acute toxicity data on the crustacean Nitocra spinipes we identified six elements (i.e. Zn, Cu, Pb, Al, K and Ca) potentially responsible for the observed ecotoxicity. However, comparing the used test methods with N. spinipes, the acute test was relatively insensitive to the eluates, whereas the (sub)chronic test (i.e. a partial life cycle test, investigating larval development ratio) was very sensitive. The overall aim of this follow-up study was to verify if the pinpointed elements could be responsible for the observed (sub)chronic toxicity of the eluates. Individual effect levels (i.e. NOEC values) for these six elements were therefore generated using the (sub)chronic test. Our results show that for six of the eight eluates, the observed ecotoxicity can be explained by individual elements not classified as ecotoxic (Al, K and Ca) according to chemical legislation. These elements will not be considered using summation models on elements classified as ecotoxic in solid material for the classification of H-14, but will have significant implications using ecotoxicological test methods for this purpose.     

Behavior of an MBT waste in monotonic triaxial shear tests

Legislation in some parts of the world now requires municipal solid waste (MSW) to be processed prior to landfilling to reduce its biodegradability and hence its polluting potential through leachate and fugitive emission of greenhouse gases. This pre-processing may be achieved through what is generically termed mechanical–biological-treatment (MBT). One of the major concerns relating to MBT wastes is that the strength of the material may be less than for raw MSW, owing to the removal of sheet, stick and string-like reinforcing elements during processing. Also, the gradual increase in mobilized strength over strains of 30% or so commonly associated with unprocessed municipal solid waste may not occur with treated wastes. This paper describes a series of triaxial tests carried out to investigate the stress–strain–strength characteristics of an MBT waste, using a novel digital image analysis technique for the determination of detailed displacement fields over the whole specimen. New insights gained into the mechanical behavior of MBT waste include the effect of density on the stress–strain response, the initial 1-D compression of lightly consolidated specimens, and the likely reinforcing effect of small sheet like particles remaining in the waste.