Influence of marble wastes on soil improvement and concrete production

Waste marble dusts are obtained by different methods of cutting marble in marble manufacturing companies. However, environmental damage can occur from the uncontrolled spill of these waste materials in natural habitats. In this study, we investigated the utilization of waste marble in the soil improvement of clayey soils, and as a fine aggregate in concrete production. Specifically, we determined the physical, mechanical and physicochemical characteristics of clayey soils with marble dust (MD) additive. The test results showed that some improvement occurred in the behavior of clay soil. Also, the cutting waste of marble sludge can be used as a filler material instead of fine aggregate in concrete production. This will reduce the porosity of the concrete due to the filling of the pores by MD.     

Autotrophic Biological Denitrification for Complete Removal of Nitrogen from Septic System Wastewater

The overall objective of this research was to develop a reliable, robust, and maintenance-free passive system for biological denitrification in on-site wastewater treatment systems. The process relies on sulfur oxidizing denitrifying bacteria in upflow packed bioreactors. Since this process consumes alkalinity, it is necessary to add a solid-phase buffer that can scavenge the H⁺ as it is generated by the biologically-mediated reaction and arrest the drop in the pH value. This study investigated the use of limestone, marble chips and crushed oyster shell as solid-phase buffers that provide alkalinity. Two bench-scale upflow column reactors and two field-scale bioreactors were constructed and packed with sulfur pellets and an alkalinity source. The pilot scale bioreactors (∼200 L each) were installed at the Massachusetts Alternative Septic System Test Center (MASSTC) in Sandwich, MA. The pilot-scale bioreactors performed better when oyster shell was used as the solid-phase buffer vis-à-vis marble chips. In both (pilot-scale and laboratory-scale) systems, denitrification rates were high with the effluent NO₃ ⁻ —N concentration consistently below 8 mg/L.     

Physico-chemical treatment of marble processing wastewater and the recycling of its sludge.

In the first part of this study, the treatability of marble processing wastewater by the coagulation-flocculation process was investigated. Optimum coagulant-flocculant doses for turbidity removal in wastewater from the cutting, faience and equalization processes were determined as 500, 200 and 500 ppm of Al2(SO4)3; 300, 500 and 300 ppm of FeCl3 and 600, 400 and 200 ppm of Agrofloc 100 (AGRON Water Treatment Technologies and Chemical Marketing Industry and Trade Limited Company, Izmir, Turkey), respectively. It was found that the removal of total solids from cutting and equalization process wastewaters was highest for the 100 ppm dosage of all chemicals used. The amount of total solids removed from faience process wastewater by Agrofloc 100 was higher than that removed by the other chemicals used. The removals of suspended solids from cutting, faience and equalization process wastewaters were similar to each other for each of the chemicals. The pH values after treatment by Agrofloc 100 were higher than the values determined after treatment by other chemicals for all process wastewater. Electrical conductivity values, however, were lower for Agrofloc 100 than for the others. Settled sludge volume experiments showed that settled sludge volumes decreased with time. The results of the quiescent settling experiment showed that the settling type could be termed flocculent settling. In the second part of the study, the usage of waste sludge from marble processing as an additive material in cement was investigated. The waste sludge originated from the wastewaters of different steps of the marble processing plant. Waste sludge was replaced with cement at various percentages by weight to prepare the mixtures of mortar. The specimens poured into the moulds were held for 24 h, removed from the moulds and held again for 28 days in lime-saturated water at 23 degrees C. Compressive and flexural strengths were evaluated with respect to percentages of waste sludge replaced with cement. The maximum compressive and flexural strengths were observed for specimens containing a 6% waste sludge when compared with control and it was also found that waste sludge up to 9% could effectively be used as an additive material in cement.     

Successful Deployment of an Innovative Environmental Technology: The Terra-Kleen Experience

The National Research Council's report, Innovations in Ground Water and Soil Cleanup: From Concept to Commercialization, reviewed the implementation of innovative remediation technologies and portrayed a bleak outlook for them. Conversely, Terra-Kleen has invented, patented, permitted, and profited through the use of an innovative technology in the current market. Terra-Kleen has implemented a solvent extraction technology for the removal of PCBs, PAHs, and chlorinated pesticides from soil, sediment, and debris. To date, Terra-Kleen has successfully processed over 23 million pounds of PCB-contaminated soil in Alaska, California, Florida, Ohio, and Oklahoma. The company has been profitable each year since its inception, and has averaged a revenue growth rate of 94 percent per year for the last four years. Corporate growth has been financed entirely through profits and conventional bank loans at favorable interest rates. This article reviews the factors that have led to Terra-Kleen's success, overviews the solvent extraction technology, and details specific projects that have implemented the technology.     

湿法脱硫装置效率不高原因分析

分析了石灰石—石膏湿法烟气脱硫系统脱硫效率不高的原因,提出了查找方法和程序。     

An overview of municipal solid waste management in China

Municipal solid waste management (MSWM) in China warrants particular attention as China has become the largest MSW generator in the world and the total amount of MSW it produces continues to increase. In recent years, central and local governments have made great efforts to improve MSWM in China. New regulations and policies have been issued, urban infrastructure has been improved, and commercialization and international cooperation have been encouraged. Considering these developments, an overview is necessary to analyze the current state as well as new opportunities and challenges regarding MSWM in China. This paper shows that since the late 1990s, the amount of MSW collected has been largely decoupled from economic growth and incineration has become an increasingly widespread treatment method for MSW. We identify and discuss four major challenges and barriers related to China’s MSWM, and propose an integrated management framework to improve the overall eco-efficiency of MSWM.     

Sustainable remediation: Quo vadis?

Sustainable remediation is at a crossroads. In a few short years it has become a mainstream topic while simultaneously maintaining its chimeral status. Sustainable remediation is a term claimed by many yet a concept apparently understood by few. Its characterization has necessitated the development of a plethora of metrics and tools yet its essence readily emerges. U.S.‐led initiatives have been adopted around the globe. Relative sustainability appraisal is easy to carry out and potentially sufficient for most site circumstances. The need to adequately protect human health and the environment has been recognized. Now the industry needs to focus our attention on protection and restoration that itself has a reasonably maximized net benefit. © 2011 Wiley Periodicals, Inc.     

RECOMMENDATIONS FOR THE MANAGEMENT OF WASTES FROM HEALTHCARE FACILITIES IN HELSINKI

In Helsinki, Finland, new guidelines have been adopted for the management of wastes from healthcare facilities. The purpose has been to rationalize waste management, reducing the amount of waste needing special treatment and lowering costs, while at the same time maintaining occupational safety and preventing environmental hazards. The changes are mainly due to the new definition of infectious waste, based on practical assessment of the possibility of spread of infection via the wastes. As a result, it has been possible to omit one chain of waste handling which has led to simpler practices and economic benefits. Sanitary landfill has been accepted for disposal of clinical waste, except for the biological waste to be incinerated for ethical reasons and infectious waste contaminated by class 4 viruses,Yersinia pestisorBacillus anthracis. Diseases caused by these micro-organisms are not a practical problem in Finland.     

动力站噪声的综合治理

辽宁轮胎厂对动力站噪声进行分步进行治理，通过采取吸声、消声和隔声措施，使动力站的混响噪声得到了大幅度下降，达到了国家标准，取得了预期的效果。     

Remediation of sites contaminated with TCE

Widespread use of trichloroethylene (TCE) in the U.S. has resulted in its frequent detection in soil and groundwater. TCE can become a health hazard after being processed in the human liver; or reductive dehalogenation in the environment may result in production of vinyl chloride, a known carcinogen. This has generated a high degree of interest in efficient and cost-effective technologies that can be used to remediate soil and ground-water contaminated with TCE. The purpose of this paper is to present and discuss relevant physicochemical properties and reactive mechanisms of TCE, and to delineate and discuss promising remediation methodologies that have been proposed and/or demonstrated for restoring contaminated subsurface environments. The information in this article has been funded wholly or in part by the U.S. EPA under contract No. 68–C8–0058 to Dynamac Corporation; it has been subjected to the Agency's peer and administrative review process and approved for publication.     

Nanoremediation and International Environmental Restoration Markets

Nanoscale zero‐valent iron (nZVI) is the most commonly used nanoremediation material. While there has been a reasonable level of application of nZVI technologies for in situ remediation in the United States, its utilization across Europe has been much more limited. There has been significant uncertainty about the balance between deployment risks and benefits for nanoparticles (NPs), which has affected the regulatory position in several countries. Some member states of the European Union (EU) take a strong precautionary view of the risks from the deployment of NPs into the subsurface, preventing the adoption of the technology. This article provides a risk–benefit assessment for nZVI based on published information and describes the steps that will be taken by a major European research project (NanoRem), as part of its work to provide a basis for better informed decision making in European environmental restoration markets. A key part of this process is dialogue between practitioners and researchers. NanoRem therefore has an active process of communication with different stakeholder networks (regulators, service providers, and site owners). NanoRem hopes to stimulate a consensus on appropriate use of nanoremediation and thereby stimulate effective technology transfer to the European remediation market. ©2015 The Authors     

多水源用水网络优化模型研究

为了解决含有多类供水水源的用水网络优化设计问题，研究了过程工业用水特点，将各用水单元看成水阱，各单元的排水看成潜在水源，从而将供水问题转化为水阱和水源的匹配问题，建立用于多水源用水网络优化的配水模型，并详细阐述该模型应用步骤及其特点。     

Glycolysis of flexible polyurethane wastes using stannous octoate as the catalyst

Flexible polyurethane foam wastes can be advantageously treated by two-phase glycolysis to recover the polyols with an improved quality compared to single-phase processes. This reaction has been traditionally catalyzed by alkanolamines, titanium compounds, or acetates. Recently, the employment of new catalysts based on potassium and calcium octoates has opened up a new way to catalyze the glycolysis of polyurethanes. In this work, the use of stannous octoate, which has never before been applied in the glycolysis reactions of polyurethanes, is proposed. The catalytic activity of stannous octoate in such a process was studied. The decomposition rate and the purity of polyol obtained were greater than those obtained using other catalysts previously employed for this application.     

A model to minimize joint total costs for industrial waste producers and waste management companies.

The model LINKopt is a mixed-integer, linear programming model for mid- and long-term planning of waste management options on an inter-company level. There has been a large increase in the transportation of waste material in Germany, which has been attributed to the implementation of the European Directive 75/442/EEC on waste. Similar situations are expected to emerge in other European countries. The model LINKopt has been developed to determine a waste management system with minimal decision-relevant costs considering transportation, handling, storage and treatment of waste materials. The model can serve as a tool to evaluate various waste management strategies and to obtain the optimal combination of investment options. In addition to costs, ecological aspects are considered by determining the total mileage associated with the waste management system. The model has been applied to a German case study evaluating different investment options for a co-operation between Daimler-Chrysler AG at Rastatt, its suppliers, and the waste management company SITA P+R GmbH. The results show that the installation of waste management facilities at the premises of the waste producer would lead to significant reductions in costs and transportation.     

In situ remediation of MTBE utilizing ozone

There has been a great deal of focus on methyl tertiary butyl ether (MTBE) over the past few years by local, state, and federal government, industry, public stakeholders, the environmental services market, and educational institutions. This focus is, in large part, the result of the widespread detection of MTBE in groundwater and surface waters across the United States. The presence of MTBE in groundwater has been attributed primarily to the release from underground storage tank (UST) systems at gasoline service stations. MTBE's physical and chemical properties are different than other constituents of gasoline that have traditionally been cause for concern [benzene, toluene, ethylbenzene, and xylenes (BTEX)]. This difference in properties is why MTBE migrates differently in the subsurface environment and exhibits different constraints relative to mitigation and remediation of MTBE once it has been released to subsurface soils and groundwater. Resource Control Corporation (RCC) has accomplished the remediation of MTBE from subsurface soil and groundwater at multiple sites using ozone. RCC has successfully applied ozone at several sites with different lithologies, geochemistry, and concentrations of constituents of concern. This article presents results from several projects utilizing in situ chemical oxidation with ozone. On these projects MTBE concentrations in groundwater were reduced to remedial objectives usually sooner than anticipated. © 2002 Wiley Periodicals, Inc.     

Biodegradability of leathers through anaerobic pathway

Leather processing generates huge amounts of both solid and liquid wastes. The management of solid wastes, especially tanned leather waste, is a challenging problem faced by tanners. Hence, studies on biodegradability of leather become imperative. In this present work, biodegradability of untanned, chrome tanned and vegetable tanned leather under anaerobic conditions has been addressed. Two different sources of anaerobes have been used for this purpose. The effect of detanning as a pretreatment method before subjecting the leather to biodegradation has also been studied. It has been found that vegetable tanned leather leads to more gas production than chrome tanned leather. Mixed anaerobic isolates when employed as an inoculum are able to degrade the soluble organics of vegetable tanned material and thus exhibit an increased level of gas production during the initial days, compared to the results of the treatments that received the anaerobic sludge. With chrome tanned materials, there was not much change in the volume of the gas produced from the two different sources. It has been found that detanning tends to improve the biodegradability of both types of leathers.     

The Application of Strict Criminal Liabilities to Spillage of Oil: The Practical Impact on Effective Spill Response

The Federal Water Pollution Control Act as amended by the Oil Pollution Act of 1990 provides criminal penalties in oil spills that result from criminal activity, gross negligence or willful misconduct on the part of the spiller. Nevertheless, the Department of Justice has seen fit to reach into unrelated legislation to potentially apply strict criminal liability to any oil spill regardless of intent.Strict criminalization of accidental oil spills is demonstrably counterproductive to effective protection of the environment from the effect of spills since it poses a serious impediment to cooperation and coordination by and between those charged by law to respond to them. This impediment is particularly dangerous since it threatens the proper functioning of the inherently sensitive “troika” Unified Command Structure that has evolved in spill response management in response to OPA-90 management requirements.Introduction of strict criminal liability for accidental spills is also particularly troublesome in that it must enlist unrelated law to influence an area that has been addressed specifically by legislation designed for that purpose; legislation that has worked well in the past 30 years to both regulate the target activities while successfully achieving the objective of protecting and improving environment quality.     

Municipal solid waste characteristics and management in Allahabad, India

Increasing population levels, rapid economic growth and rise in community living standard accelerates the generation rate of municipal solid waste (MSW) in Indian cities. Improper management of MSW causes hazards to inhabitants. The objectives of the study are to determine the quantitative and qualitative characteristics of MSW along with basic information and to create GIS maps for Allahabad city. The samples have been randomly collected from various locations and analyzed to determine the characteristics of MSW. A questionnaire survey has been carried out to collect data from inhabitants including MSW quantity, collection frequency, satisfaction level, etc. The Geographic Information System (GIS) has been used to analyze existing maps and data, to digitize the existing sanitary ward boundaries and to enter the data about the wards and disposal sites. The total quantity of MSW has been reported as 500 ton/day, and the average generation rate of MSW has been estimated at 0.39 kg/capita/day. The generated ArcGis maps give efficient information concerning static and dynamic parameters of the municipal solid waste management (MSWM) problem such as the generation rate of MSW in different wards, collection point locations, MSW transport means and their routes, and the number of disposal sites and their attributes.     

Impact of Construction Waste Disposal Charging Scheme on work practices at construction sites in Hong Kong

Waste management in the building industry in Hong Kong has become an important environmental issue. Particularly, an increasing amount of construction and demolition (C&D) waste is being disposed at landfill sites. In order to reduce waste generation and encourage reuse and recycling, the Hong Kong Government has implemented the Construction Waste Disposal Charging Scheme (CWDCS) to levy charges on C&D waste disposal to landfills. In order to provide information on the changes in reducing waste generation practice among construction participants in various work trades, a study was conducted after 3 years of implementation of the CWDCS via a structured questionnaire survey in the building industry in Hong Kong. The study result has revealed changes with work flows of the major trades as well as differentiating the levels of waste reduced. Three building projects in the public and private sectors were selected as case studies to demonstrate the changes in work flows and the reduction of waste achieved. The research findings reveal that a significant reduction of construction waste was achieved at the first 3 years (2006–2008) of CWDCS implementation. However, the reduction cannot be sustained. The major trades have been influenced to a certain extent by the implementation of the CWDCS. Slight improvement in waste management practices was observed, but reduction of construction waste in the wet-finishing and dry-finishing trades has undergone little improvement. Implementation of the CWDCS has not yet motivated subcontractors to change their methods of construction so as to reduce C&D waste.     

化工厂排放SO2对周围植物的影响

对某厂区及常年盛行风下风向地区植物受ＳＯ２危害情况进行了调查，并测定了部分植物叶片中的硫含量。从植物叶片中的硫含量可间接地判断大气被ＳＯ２污染的程度及植物对ＳＯ２吸收与抵抗能力的强弱。