Handling leachate from glass cullet stockpiles

Mixed glass cullet (crushed recycled glass containers) is stockpiled uncovered before use as roadway construction aggregate or daily cover in landfills. Rainwater that leaches through the stockpiles dissolves and suspends contaminants such as those from food residuals and paper labels. The objective of this study was to determine leachate quantity and quality from cullet stockpiles as a basis for development of Best Management Practices (BMPs). Four 35-tonne field stockpiles were set up for leachate analysis and to determine the effects of mechanical turning treatment on the leachate. Field-collected leachate and laboratory-generated washwater of cullet (water:cullet = 3:1 by weight) were both analyzed for basic wastewater parameters, which showed pollutant levels comparable to or higher than those of untreated domestic wastewater or urban stormwater. While organic contamination decreased substantially (e.g., washwater BOD > 95% reduction), TKN and total-phosphorus levels in leachate ranged between 11.6–154 mg L^?1 and 1.6–12.0 mg L^?1, respectively, and remained comparable to levels found in untreated domestic wastewater after four months. Turning enhanced the degradation of the organic constituents inside the stockpiles, which was confirmed by elevated temperatures. Based on this study, leachate from glass cullet stockpiles should not be released to surface water. For leachate from long-term cullet stockpiles, release to groundwater should be only done after treatment to reduce nitrogen levels.     

Use of life cycle assessment as decision-support tool for water reuse and handling of residues at a Danish industrial laundry.

This analysis presents the results of a life cycle assessment (LCA) carried out on six alternative options for the recycling of water at a Danish industrial laundry for workwear. The study focuses on the handling and disposal of the wet residues generated when wastewater is treated for recycling, and in accounting for long-term potential toxicity impacts. The analysed options are a combination of two water-upgrading technologies: biofilter and ultrafiltration, and three residue disposal alternatives: biogas followed by incineration of sludge at local wastewater treatment plant, thermal vitrification treatment for production of vitrified sand, and mineralization in a sludge bed. It is concluded from the results that with the current Danish environmental policy priorities, the environmental impacts of highest priority are the toxicity effects derived from the presence of heavy metals in the residues. Heavy metals originate from the dirt in the workwear that is washed in the laundry. It is further concluded that the studied water treatment technologies satisfy both the need of clean water for recycling and simultaneously help controlling a safe disposal of pollutants by concentration of the residues. The results of the study also confirm the potential of LCA as a decision-support tool for assisting water recycling initiatives and for residue handling management. The handling of residues has been identified as a stage of the water recycling strategy that bears important environmental impacts. This holistic perspective provided by LCA can be used as input for the definition of environmental management strategies at an industrial laundry, and the prioritization of investments to the environmental profile of laundry processes. In this case-study, the results of the LCA are made operational by, for example, selecting the water treatment technology which is associated wih a safe disposal of the wet residue. It is important to bear in mind that such prioritization depends on national boundary conditions. In the case study analysed, the boundary conditions steer the weighing of the environmental impacts, following the current Danish environmental policy priorities.     

Evaluation of bangkok sewage sludge for possible agricultural use.

Bangkok (Thailand) covers more than 1500 km2 and has 10 million inhabitants. The disposal of wastewater is creating huge problems of pollution. The estimated amount of sewage sludge was estimated to be around 108 tonnes dry matter (DM) per day in 2005. In order to find a lasting way of disposal for this sewage sludge, the suitability of the sludge produced from three waste-water treatment plants for use as fertilizing material was investigated. Monthly samplings and analysis of sewage sludge from each plant showed that the composition of sludge varied according to the area of collection and period of sampling, and there was no link to rainfall cycle. Plant nutrient content was high (i.e. total N from 19 to 38 g kg(-1) DM) whereas organic matter content was low. The concentrations of heavy metals varied between sludge samples, and were sometimes higher than the E.U. or U.S. regulations for sewage sludge use in agriculture. Faecal coliforms were present in the sludge from one of the plants, indicating a possible contamination by night soil. In order to decrease this potentially pathogenic population the sewage sludge should be heated by composting. As the C/N ratio of sewage sludge was low (around 6) some organic by-products with high carbon content could be added as structural material to enhance the composting.     

The environmental and biosecurity characteristics of livestock carcass disposal methods: A review

Livestock mortalities represent a major waste stream within agriculture. Many different methods are used throughout the world to dispose of these mortalities; however within the European Union (EU) disposal options are limited by stringent legislation. The legal disposal options currently available to EU farmers (primarily rendering and incineration) are frequently negatively perceived on both practical and economic grounds. In this review, we assess the potential environment impacts and biosecurity risks associated with each of the main options used for disposal of livestock mortalities in the world and critically evaluate the justification for current EU regulations. Overall, we conclude that while current legislation intends to minimise the potential for on-farm pollution and the spread of infectious diseases (e.g. transmissible spongiform encephalopathies, bacterial pathogens), alternative technologies (e.g. bioreduction, anaerobic digestion) may provide a more cost-effective, practical and biosecure mechanism for carcass disposal as well as having a lower environmental footprint. Further social, environmental and economic research is therefore warranted to assess the holistic benefits of alternative approaches for carcass disposal in Europe, with an aim to provide policy-makers with robust knowledge to make informed decisions on future legislation.     

Application of sewage sludge compost on highway embankments

More and more sewage sludge is being produced in China. Safe and economical methods for sewage sludge disposal should be found considering the increase in sewage treatment. In order to verify the feasibility of sludge disposal on newly built highway embankments, five treatments (0, 15, 30, 60 and 120 tons ha⁻¹) of sewage sludge compost (SSC) were added to a silty-clay embankment soil on the Xi-Huang highway. The results showed that amendment with SSC increased soil available N, available P, organic matter, cation exchange capacity, and water content, and decreased soil bulk density. Application of SSC enhanced ryegrass growth and reduced runoff and soil erosion. Heavy metal losses from sediments in runoff remained constant or decreased relative to the control until a rate of 60 tons ha⁻¹ was exceeded, when heavy metal losses appeared to increase.     

A Review Of The Management Of Radioactive Wastes In Medical Institutes

Amongst the waste from health care institutions, radioactive waste represents a special category since it cannot be modified or neutralized by any available conventional means. Accordingly, disposal of radioactive waste can mean only its transfer from a place where it represents some hazard to somewhere else where it can be retained without undue risk. Radioactive waste arises in health care institutes as a result of diagnostic, therapeutical or research uses of unsealed radioactive substances. Sometimes, sealed sources withdrawn from further use might also be subject to disposal. Most radionuclides used in medicine are short-lived beta-, or beta-gamma emitters and represent a low risk, if properly handled, that is if due care is taken to prevent significant contamination of the workplace and personnel. Low-activity gaseous and liquid waste can usually be discharged to the environment directly; medium-activity or high-activity waste should be stored for variable periods to allow natural decay before specialized disposal.This paper presents a review of the different types of radioactive wastes produced in hospitals, and introduces many of the sources of generation and subsequent disposal options. An example is given of the wide range of guidance available, both by national bodies in Hungary and international agencies, such as the International Atomic Energy Agency (IAEA), World Health Organisation (WHO) and International Committee on Radiological Protection (ICRP).     

用废铝渣制备聚合硫酸铝

将铝材厂前处理过程产生的废铝渣用硫酸溶解,然后加入有机添加剂等进行聚合反应,制备新型水处理剂——聚合硫酸铝（PAS）。用PAS与聚合氯化铝（PAC）进行絮凝对比实验,结果表明,对于硅藻土浊度水、水源水和工业废水等,PAS比PAC具有更优异的除浊、脱色、去除COD和悬浮物的效果。该工艺既可回收利用废铝渣,又可省去废渣处置费用,为废铝渣的综合利用提供了实用技术。     

Transformation of phosphorus during drying and roasting of sewage sludge

Sewage sludge (SS), a by-product of wastewater treatment, consists of highly concentrated organic and inorganic pollutants, including phosphorus (P). In this study, P with different chemical fractions in SS under different drying and roasting temperatures was investigated with the use of appropriate standards, measurements, and testing protocol. The drying and roasting treatment of SS was conducted in a laboratory-scale furnace. Two types of SS samples under different treatment temperatures were analyzed by ³¹P NMR spectroscopy. These samples were dried by a vacuum freeze dryer at ?50 °C and a thermoelectric thermostat drying box at 105 °C. Results show that the inorganic P (IP) content increased as the organic P content decreased, and the bio-availability of P increased because IP is a form of phosphorous that can be directly absorbed by plants. ³¹P NMR analysis results indicate the change in P fractions at different temperatures. Non-apatite P was the dominant form of P under low-temperature drying and roasting, whereas apatite P was the major one under high-temperature drying and roasting. Results indicate that temperature affects the transformation of P.     

Determination of inorganic and organic priority pollutants in biosolids from meat processing industry

The biosolids (BS) generated in the wastewater treatment process of a meat processing plant were monitored and the priority pollutant content was characterized. The trace metal and organic pollutant content – polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/PCDF) – were determined quantitatively and compared to guideline limits established by the US EPA and EU. PCBs were not detected in the solid samples, while trace metals, PAHs and PCDD/PCDF were detected in concentrations below the limits established by international standards. Toxic equivalent factors were evaluated for the biosolids, and the results proved that these wastes can be safely deposited on land or used in combustion/incineration plants. Since no previous data were found for meat processing waste, comparisons were made using municipal sewage sludge data reported in the literature. Since, this report monitored part of the priority pollutants established by the US EPA for meat and poultry processing wastewater and sludge, the results verified that low pollution loads are generated by the meat processing plant located in the southern part of Brazil. However, the BS generated in the treatment processes are in accordance with the limits established for waste disposal and even for soil fertilizer.     

Characterization of oily sludge from a wastewater treatment plant flocculation-flotation unit in a petroleum refinery and its treatment implications

Partly due to the complex and variable composition of oily sludge generated by the petroleum industry, cost-effective treatment and proper disposal pose considerable challenges worldwide. In this study, an extended component-based analysis of the oily sludge from a flocculation-flotation unit of a wastewater treatment system in a refinery in Sweden was carried out over 1 year. The heterogeneity of the oily sludge is illustrated by the wide ranges of concentrations found for different chemical components, particularly metals. Among the petroleum hydrocarbons, the most abundant compounds were nonpolar aliphatic hydrocarbons (63.7 ± 16.7 g kg⁻¹); from the benzene, toluene, ethylbenzene, and xylene group, xylenes (91–240 mg kg⁻¹) were most abundant; and among polycyclic aromatic hydrocarbons, naphthalene (25.7 ± 21.4), fluorene (27.25 ± 10.0), and phenanthrene (43.8 ± 18.4 mg kg⁻¹) were most abundant (all results in terms of dry matter). Based on the EU guidelines and the mean concentration values for metals found in the oily sludge, e.g., Pb (135.4 ± 125.8), Cu (105.2 ± 79.1), Hg (42.8 ± 31.3), Ni (320 ± 267.4), and Zn (1321.7 ± 529.9 mg kg⁻¹), disposal of oily sludge even in landfills for hazardous waste is not allowed. The organic content of the sludge can be reduced through biotreatment, but not the metal content. A multistep component-based treatment scheme is therefore needed.     

LEHR superfund stormwater runoff and putah creek mercury issues

Stormwater runoff from the University of California, Davis/U.S. Department of Energy Laboratory for Energy‐Related Health Research (UCD/US DOE LEHR) Superfund site located on the University of California campus in Davis, California, has been found to contain over 500 ng/L of total recoverable mercury, which is about ten times the California Toxics Rule criterion. This stormwater runoff is discharged to Putah Creek, which is Clean Water Act Section 303(d) listed as impaired for excessive mercury bioaccumulation in edible fish. A discussion is presented on the potential impact of the mercury in stormwater runoff from LEHR leading to excessive bioaccumulation of mercury in Putah Creek fish. The mercury in the stormwater runoff is derived from former flooding of the soils near the creek, which contains mercury derived from abandoned upstream mercury mines located in the Coast Range Vaca Hills to the west of LEHR. The implications of this situation for implementing a Total Maximum Daily Load (TMDL) to control mercury in stormwater runoff to Putah Creek are presented. © 2009 Wiley Periodicals, Inc.     

Managing petroleum refining wastes by thermal desorption

The U.S. Environmental Protection Agency has developed regulations under the Hazardous and Solid Waste Amendments (HSWA) of 1984 to restrict the land disposal of hazardous wastes. As a result of the regulations, all hazardous wastes to be placed on the land must meet treatment standards based on the performance of the best demonstrated available technology (BDAT) identified for individual waste classifications. The Marathon Oil Company is currently evaluating innovative technologies for managing listed waste materials, with a focus on waste minimization and recycling. Remediation Technologies, Inc. (ReTeC) has conducted testing on wastewater treatment sludges from three Marathon refineries using a proprietary thermal desorption technology. The results from these tests have demonstrated that the technology has the ability to consistently meet BDAT treatment standards, while preferentially separating and condensing residual moisture and oils from the material.     

Comparative study of the methods used for treatment and final disposal of sewage sludge in European countries

Municipal wastewater treatment results to the production of large quantities of sewage sludge, which requires proper and environmentally accepted management before final disposal. In European Union, sludge management remains an open and challenging issue for the Member States as the relative European legislation is fragmentary and quite old, while the published data concerning sludge treatment and disposal in different European countries are often incomplete and inhomogeneous. The main objective of the current study was to outline the current situation and discuss future perspectives for sludge treatment and disposal in EU countries. According to the results, specific sludge production is differentiated significantly between European countries, ranging from 0.1 kg per population equivalent (p.e.) and year (Malta) to 30.8 kg per p.e. and year (Austria). More stringent legislations comparing to European Directive 86/278/EC have been adopted for sludge disposal in soil by several European countries, setting lower limit values for heavy metals as well as limit values for pathogens and organic micropollutants. A great variety of sludge treatment technologies are used in EU countries, while differences are observed between Member States. Anaerobic and aerobic digestion seems to be the most popular stabilization methods, applying in 24 and 20 countries, respectively. Mechanical sludge dewatering is preferred comparing to the use of drying beds, while thermal drying is mainly applied in EU-15 countries (old Member States) and especially in Germany, Italy, France and UK. Regarding sludge final disposal, sludge reuse (including direct agricultural application and composting) seems to be the predominant choice for sludge management in EU-15 (53% of produced sludge), following by incineration (21% of produced sludge). On the other hand, the most common disposal method in EU-12 countries (new Member States that joined EU after 2004) is still landfilling. Due to the obligations set by Directive 91/271/EC, a temporary increase of sludge amounts that are disposed in landfills is expected during the following years in EU-12 countries. Beside the above, sludge reuse in land and sludge incineration seem to be the main practices further adopted in EU-27 (all Member States) up to 2020. The reinforcement of these disposal practices will probably result to adoption of advanced sludge treatment technologies in order to achieve higher pathogens removal, odors control and removal of toxic compounds and ensure human health and environmental protection.     

Papermill industrial waste as a sustainable source for high efficiency absorbent production

Papermill sludge (PMS) is generated during the wastewater treatment process of paper production. Its handling and disposal techniques are of great concern for the environment. It can be landfilled as a waste, or it can be recycled and converted into useful products of high value. It has a very promising application as an absorbing agent for the cleaning of water surfaces polluted with hydrophobic substances (vegetable, synthetic and mineral oils, animal fats, fuels, organic chemicals and even coal dust). Here, we present the pretreatment procedure (hydrophobation, mechanical and thermal treatments) of PMS that produces a lightweight absorbent material (HAWSC - high efficiency absorbent for water surface cleaning), which floats on the water surface and binds hydrophobic pollutants with considerably higher efficiency than commercially available mineral and synthetic absorbents. After its application, it can be incinerated, due to its high caloric value, to produce energy. The incineration residues can then be formed into granules that can be used as an efficient absorbent for fluids spilled onto solid surfaces.     

Greenhouse gases emission from municipal waste management: The role of separate collection

The municipal solid waste management significantly contributes to the emission in the atmosphere of greenhouse gases (e.g. CO₂, CH₄, N₂O) and therefore the management process from collection to treatment and disposal has to be optimized in order to reduce these emissions. In this paper, starting from the average composition of undifferentiated municipal solid waste in Italy, the effect of separate collection on greenhouse gases emissions from municipal waste management has been assessed. Different combinations of separate collection scenarios and disposal options (i.e. landfilling and incineration) have been considered. The effect of energy recovery from waste both in landfills and incinerators has also been addressed. The results outline how a separate collection approach can have a significant effect on the emission of greenhouse gases and how wise municipal solid waste management, implying the adoption of Best Available Technologies (i.e. biogas recovery and exploitation system in landfills and energy recovery system in Waste to Energy plants), can not only significantly reduce greenhouse gases emissions but, in certain cases, can also make the overall process a carbon sink. Moreover it has been shown that separate collection of plastic is a major issue when dealing with global warming relevant emissions from municipal solid waste management.     

Recent applications of phytoremediation technologies

Although the application of microbe biotechnology has been successful with petroleum-based constituents, microbial digestion has met with limited success for widespread residual organic and metal pollutants located above the potentiometric surface. Vegetation-based remediation, on the other hand, shows potential for accumulating, immobilizing, and transforming low levels of persistent contamination from the subsurface. Agricultural bioremediation, called geobotany or phytoremediation, relies on the remediating abilities of contaminant-accumulating plants to remove contamination from soil or groundwater. In natural ecosystems, plants act to filter and metabolize substances generated by nature. Phytoremediation affirmatively applies this process to help clean up contamination created by artificial means. Plants have proven effective at remediating areas contaminated with organic chemical wastes such as petroleum products, solvents, wood preservatives, pesticides, and metals. Phytoremediation is not the best technology for every site but has shown success with lead, cadmium, zinc, and radionuclides. The phytoremediation process takes much longer than conventional methods to clean a site and is dependent upon the type and degree of contamination. Concentrations must be within a narrow range of tolerable levels and the presence of the contamination must be at the appropriate depth. Nevertheless, phytoremediation offers an effective alternative to conventional, engineered remedial plans that usually involve costly activities like excavation, treatment, and disposal of soil or pump-and-treat technologies for groundwater. Phytoremediation also seems to be a promising new technology for the treatment of stormwater, industrial wastewater, and sewage. The relative low costs of capital for start-up together with negligible operations and maintenance costs provide a strong incentive for further investigation and development of phytoremediation projects.     

光合细菌及其在化工有机废水处理方面的应用

光合细菌作为一类古老的细菌类群，已经在众多领域得到应用。利用光合细菌处理有机废水具有处理有机负荷高、占地面积小、便于管理、能耗低、投资费用少、菌体可以回收利用等优点，已经引起人们的重视。对光合细菌在处理化工有机废水方面的研究和应用进行了综述，指出光合细菌处理法的优缺点和发展趋势，认为光合细菌在有机废水处理方面的应用前景广阔。     

Bioremediation of Dissolved and Free Phase Oil in Wastewater from Equipment Maintenance Activities

Land treatment facilities can provide effective treatment of secondary oily wastewater from maintenance operations, particularly in arid climates. Soil and underlying groundwater from a land treatment facility, which has been operating for eight years, were analyzed to determine the effectiveness of using bioremediation for the treatment of dissolved and free‐phase oil in maintenance wastewater. The study was conducted at a mining site in Western Australia. The facility was capable of treating 140 kiloliters (kL) of oily wastewater per day. The average petroleum hydrocarbon content of the wastewater was 2 percent weight per volume (w/v) based on data available for the first five years. The soil data indicate that the land treatment process has been operating efficiently even at high wastewater loadings with maximum degradation rates of 10–242 mg/kg per day. Based on the soil data, there is no evidence of accumulation of any metal or polycyclic aromatic hydrocarbon (PAH) compounds. The land treatment facility has led to only low levels of TPH (total petroleum hydrocarbons) contamination (<4 ppm) in the underlying groundwater. However, nitrate concentrations in the groundwater were shown to increase over the first five years of the facility's operation. This article reports and discusses the operational data from the land treatment process, illustrating its effectiveness in treating oily wastewater. © 2001 John Wiley & Sons, Inc.     

Changes in soil characteristics during landfill leachate irrigation of Populus deltoides

The effects of wastewater application on electrical conductivity, water retention and water repellency of soils planted with Populus deltoides (eastern cottonwood) and irrigated with different concentrations of landfill leachate and compost wastewater, tap water and nutrient solution were evaluated. Substrate water content at field capacity (?0.033 MPa) and at permanent wilting point (?1.5 MPa) was determined with a pressure plate extractor to assess available water capacity of the substrate. A water drop penetration test was used to determine substrate water repellency. The biomass of nutrient and landfill leachate treatments was significantly (P < 0.05) greater compared to the tap water and compost wastewater treatments. All treatments increased substrate water content at field capacity and at permanent wilting point. Landfill leachate significantly increased available water capacity (up to 52%); treatment with compost wastewater significantly decreased it (25–47%). All substrates showed increased water repellency after the experiment at field capacity and permanent wilting point comparing to the original substrate. The strongest influence on water repellency at both field capacity and permanent wilting point showed irrigation with compost wastewater and tap water. Pronounced influence on substrate’s water repellency of compost wastewater could be contributed to a high content of dissolved organic carbon, whereas Mg and Ca cations caused flocculation and consequent water repellency of the substrate irrigated with tap water. The results indicate that soil physical characteristics must be closely monitored when landfill leachate and compost wastewater are used for irrigation to avoid long term detrimental effects on the soil, and consequently on the environment. Due to the complexity of the compost wastewater quality the latter should be applied on open fields only after prior pre-treatment to reduce dissolved organic carbons, or alternatively, compost wastewater should be added only intermittently and in diluted ratios.     

Cost‐Effective Sediment Dredge Disposal Options for Small Craft Harbors in Canada

Sediment dredge disposal options were reviewed to improve cost‐effectiveness and environmental safety for dredging of coastal sediments at the Department of Fisheries and Oceans Small Craft Harbours (DFO‐SCH) program in Canada. Historically, contaminated dredge sediments exceeding federal guidelines were disposed of in nearby landfills. Recent federal regulatory changes in sediment quality guidelines adopted by provincial regulators in Canada has resulted in updates to guidelines for disposal of contaminated solids in landfills. Updates now require specific and general disposal options for contaminated dredge material destined for land‐based disposal, resulting in more expensive disposal in containment cells (if contaminated sediments exceed federal guidelines). However, as part of this study, a leachate testing method was applied to contaminated sediments to simulate migration of potential contaminants in groundwater. Using this approach, leachate quality was compared to federal freshwater criteria and drinking water quality guidelines for compliance with new regulations. Leachate testing performed on the highest sediment contaminant concentrations triggered less than 2 percent potable water exceedances, meaning that most dredge spoils could be disposed of in privately owned or provincially operated landfill sites, providing less expensive disposal options compared to containment cell disposal. Current dredge disposal practices were reviewed at 35 harbor sites across Nova Scotia and their limitations identified in a gap analysis. Improved site management was developed following this review and consultation with interested marine stakeholders. New disposal options and chemical analyses were proposed, along with improvements to cost efficiencies for management of dredged marine sediments in Atlantic Canada. © 2013 Wiley Periodicals, Inc.