William Hogland

Lead and vanadium removal from a real industrial wastewater by gravitational settling/sedimentation and sorption onto Pinus sylvestris sawdust

Batch sorption with untreated Pinus sylvestris sawdust after settling/sedimentation phase to remove vanadium and lead from a real industrial wastewater was investigated using different adsorbent doses, initial pH, and contact time. The development of pH along the sorption test and a parallel investigation of metals release from sawdust in distilled water were carried out. In order to evaluate kinetic parameters and equilibrium isotherms, Lagergren first-order, pseudo-second-order, intra-particle diffusion and Freundlich models were explored. When the initial pH was reduced from 7.4 to 4.0, the sorption efficiency increased from 32% to 99% for Pb and from 43% to 95% for V. Whereas, V removal was positively correlated with the adsorbent dose, Pb removal was not. The sorption process was best described by pseudo-second-order kinetics. According to Freundlich parameters (K(f) and n) sawdust presented unfavourable intensity for sorption of V.

Water balance for landfills of different age

Water-related processes in landfills are discussed with emphasis on internal processes such as field capacity, moisture variation in time and space, and macropore flow. Runoff production and evaporation from landfills in Sweden of different age are investigated. It is clarified in what ways and for how long a closed municipal landfill differs from an ordinary land area from a hydrological point of view.

Physical, biological and chemical processes during storage and spontaneous combustion of waste fuel

Physical, biological and chemical processes during storage and spontaneous combustion of waste fuel

Assessment and System Analysis of Industrial Waste Management

Considerable economic as well as environmental benefits can be achieved when appropriate industrial waste management is implemented. The objective of this study was to find a method of organizing a waste management system and of obtaining an overview of the whole system. The method proposed emphasizes the optimization of waste management with regard to energy, economy and environmental impact in separate evaluations. The case study presented illustrates how the method was applied to the Stora Enso Hylte AB paper-mill in Sweden. The waste management systems studied were: (1) the existing system (used as a reference), (2) an energy-recovery system (in which the waste produced is used for energy production, as far as is possible), and (3) a material-recovery system (in which waste is recovered or re-used, as far as is possible). The second system was found to be preferable with regard to energy, economy and environmental impact, although the lowest carbon dioxide emissions was obtained with the first system. The method presented is also suitable as a basis for the development of more specific methodologies for the analysis of waste handling systems applicable to other branches of industry.

Physical, Biological and Chemical Effects of Unsorted Fractions of Industrial Solid Waste in Waste Fuel Storage

Technical, biological and environmental problems encountered in the storage of industrial waste fuel are analysed and discussed. Measurements of temperature, moisture content, oxygen, methane and carbon dioxide during the storage period are presented. It is shown that the temperature increases rapidly to 70-90°C and the oxygen content decreases to almost zero in the lower parts of the storage pile. After several months of high but stable temperature conditions, self-ignition occurred in the storage piles. The test results are related to the proper design of storage piles.

Remediation of an old landsfill site

The Baltic Sea Region has a large number of landfills that need remediation after care routines and control, in order to avoid future emissions to the environment and to fulfil the demands in the EU Waste Council Directive on the landfill of waste. Based on the Måsalycke test screening, an excavation of whole or of parts of the landfill can be seen as a potential measure for some of the old landfills. The material excavated in the test was screened into the fractions: < 18 mm, 182-50 mm and > 50 mm. The coarsest fraction (> 50 mm) contained 50% wood and paper. The medium-sized fraction (18–50 mm) contained stones and indefinable soil-like material, while the fine fraction contained peat-like material with some other small waste components. The spectral analysis of heavy metals indicated only high concentrations of zinc and there was no significant difference between the fine and the medium-sized fractions. The medium sized and the unsorted fraction was moisturized and refilled into the pit. The methane content in the landfill gas from the pit was 50–57% in the sorted material with a flow of 8–17 l/min and 38–57% in the unsorted fraction with a flow of 2–13 l/min during the first 1.5 year. The Måsalycke landfill is in the methanogenic phase and leachate concentrations are normal. Landfill mining can be used to prolong the landfill lifetime and/or used as a tool for remedial actions in contaminated sites.

Interaction of inorganic anions with iron-mineral adsorbents in aqueous media--a review.

A number of inorganic anions (e.g., nitrate, fluoride, bromate, phosphate, and perchlorate) have been reported in alarming concentrations in numerous drinking water sources around the world. Their presence even in very low concentrations may cause serious environmental and health related problems. Due to the presence and significance of iron minerals in the natural aquatic environment and increasing application of iron in water treatment, the knowledge of the structure of iron and iron minerals and their interactions with aquatic pollutants, especially inorganic anions in water are of great importance. Iron minerals have been known since long as potential adsorbents for the removal of inorganic anions from aqueous phase. The chemistry of iron and iron minerals reactions in water is complex. The adsorption ability of iron and iron minerals towards inorganic anions is influenced by several factors such as, surface characteristics of the adsorbent (surface area, density, pore volume, porosity, pore size distribution, pHpzc, purity), pH of the solution, and ionic strength. Furthermore, the physico-chemical properties of inorganic anions (pore size, ionic radius, bulk diffusion coefficient) also significantly influence the adsorption process. The aim of this paper is to provide an overview of the properties of iron and iron minerals and their reactivity with some important inorganic anionic contaminants present in water. It also summarizes the usage of iron and iron minerals in water treatment technology.

The unit superstructure during the construction period

The “Unit Superstructure” is a new method of constructing the superstructure in traffic areas. The construction consists of a pervious surface, open aggregate and a geotextile in which rain and surface water are distributed by means of infiltration to the underlying soil. Two test areas have been constructed in Lund and tests of the Unit Superstructure have been carried out for one year. The first preliminary results from the study are presented in this paper. The investigation shows that the pervious surface is most sensitive to clogging during the period when buildings are still under construction in the area. Lorries, trucks and building machines spread soil particles and dirt on the asphalt surface. This gradually reduced the infiltration capacity. A 470 m2 parking lot constructed with the Unit Superstructure method was exposed to heavy traffic of building machines during a period of 12 months. Subsequently, the surface was dug up in order to estimate the pollution level. Samples were taken at different levels and analyzed with respect to different constituents. Surface protection during the construction period or some kind of cleaning of the surface afterwards is a necessity. Infiltration tests from one of the oldest Unit Superstructures in Sweden are also presented in the paper.

The performance of a natural treatment system for landfill leachate with special emphasis on the fate of organic pollutants

A natural treatment system for the treatment of leachate was studied at Moskogen landfill in southern Sweden. This facility consists of three consecutive ponds and a soil-plant (SP)-system. A test area, receiving water from the third pond with the same hydraulic load as the SP-system, was used for estimation of the latter system. Quality parameters including biochemical oxygen demand, total organic carbon, ammonium, nitrate, orthophosphate, and total suspended solids along the treatment line were determined as well as soluble metals (Cu, Cd, Zn, Cr, Ni, and Pb). In addition a thorough investigation along the treatment line has also been performed concerning volatile organic compounds and semi-volatile organic compounds. Non-polar organic compounds were investigated using gas chromatography-mass spectrometry. Quantification was based on the assumption of equal response for the compounds found in comparison with the chosen marker substances. For polar, water-soluble compounds the measurements were restricted to phenolic compounds using high-performance liquid chromatography. Several different types of organic compounds were found in the raw leachate including aromatics, benzene-sulfonamides, biphenyls, naphthalene, organic phosphates, polycyclic aromatic hydrocarbons, polychlorinated biphenyls, phenols and phthalates. The treatment system efficiently reduced organic pollutants, heavy metals, and nitrogen/phosphorous compounds. Most metals and organic compounds in the leachate were already significantly reduced to a low level in the treatment ponds and ammonium-N was efficiently transformed to nitrate-N in the SP-system.

Biotreatability of wastewater generated during machinery washing in a wood-based industry: COD, formaldehyde and nitrogen removal.

This paper describes biotreatability tests for treating a wastewater stream generated by wood-floor industries after cleaning and washing of machinery used to apply urea-formaldehyde resins onto wood-fiber boards. A biological system consisting of an anaerobic-intermittently aerated reactor in lab-scale was constructed. Since the investigated wastewater is intermittently generated, the system was designed to operate in batch mode. The treatment focused on removal of formaldehyde and COD, as well as the efficiency of nitrification-denitrification. The proposed cheap and relatively simple-to-operate biological system achieved COD and formaldehyde removal rates of 65+/-11% and 93+/-4% respectively. In spite of anaerobic ammonium removal and denitrification, the intermittently-aerated reactor showed poor performance for nitrification. Therefore, a better understanding of constraints for the process improvement is necessary. Regardless the constraints faced during the investigation, the proposed system can be considered feasible to partially reduce a great amount of biodegradable compounds in urea-formaldehyde-based wastewaters. However, to comply with strict threshold limits for industrial effluent discharges, the use of biological treatment combined with more advanced processes is needed to achieve a better quality of the final effluent.