Korea's policy instruments for waste minimization

This paper considers the current status of waste generation and waste treatment trends, and introduces a wide variety of policy instruments for waste minimization at every stage of economic activity in Korea, i.e., production, distribution, and consumption. At each stage, the Korean government has imposed a policy mix of direct regulations and economic incentives. These policy instruments have made definite contributions to a reduction of waste generation and an increase in the recycling rate. Despite these fruitful outcomes, there are still some shortcomings with respect to efficiency and equity. Among other aspects, this paper examines three representative economic incentives – the charge system, the volume-based-collection fee system, and the deposit–refund system – and identifies shortcomings in each. Some suggestions are made for the creation of better systems of economic incentives. However, many experts insist that this kind of piecemeal change in each policy instrument is not enough to achieve the ultimate goal of resource circulation and an environmentally friendly society, especially in Korea, which is a country with little land, a high population density, and a high economic growth rate. Among experts, special emphasis is placed on the activation of recycling industries to achieve these goals. Received: April 2, 2001 / Accepted: September 10, 2001     

Porous structure of activated carbon prepared from waste newspaper

In an earlier report, we presented a method for preparing activated carbon from waste newspaper as a way to recycle used paper for a purpose other than producing raw material for paper-making. In this article, we consider the porous structure of the activated carbon that affects its adsorption properties for various substances. The specific surface area of activated carbon prepared from waste newspaper was 838 m²/g, the micropore volume was 0.368 ml/g, and the mesopore volume was 0.138 ml/g, which is about the same as commercially available activated carbon. The activated carbon prepared from waste newspaper usually has a high content of ash, which makes little contribution to the adsorption properties. In particular, as compared with reagent-activated carbon, the quantities of mesopores with a pore radius of 3–25 nm and macropores with a pore radius of 25–250 nm were 8 and 14 times larger, respectively. Activated carbon prepared from waste newspaper has a well-developed porous structure, particularly in the mesopore and macropore ranges. Received: July 12, 1999 / Accepted: March 8, 2000     

Definition of compostability criteria for packaging: Initiatives in Italy

The management of solid waste is changing. The traditional approach based on landfilling of mixed refuses is shifting toward a system based on the at-source sorting of waste into specific fractions. The biological treatment of the organic fraction is considered to be an appropriate form of disposal not only for the “traditional≓ feedstock such as food scraps and vegetable and garden waste, but also for biodegradable packaging, when not recyclable in other ways. Any change from a complex system to another is difficult since many factors are to be organized and optimized. Industry must develop and manufacture compostable products, municipalities must build composting plants and organize source-separated collection, and regulatory bodies must define widely acceptable criteria of compostability. In Europe, the European Union has assigned the last task to the CEN, to provide common criteria and avoid hindrance to commercial exchanges. In Italy the UNI, the national standardization organization, has produced a working document to contribute to the discussion on the European level. In this paper the UNI scheme is described. A condensed version of this paper was presented by one of the authors (F.D.I.) at the 5th annual meeting of the BEDP Society, held in Nashville, September 22–26, 1996, during a session covering International Standards for Biodegradation Testing.     

Pore structure and adsorption properties of carbonized material prepared from waste paper

We have already reported the adsorptivity and pore structure of activated carbon made from waste newspaper in order to use the waste paper for purposes other than paper-making stock. However, manufacturing the activated carbon may not necessarily be an advantageous method based on environmental concerns and the effective use of the resource because the reaction during the activating process is endothermic and the amount of carbon consumed is significant. Here, we examine the pore structure and adsorption properties of waste newspaper used as an adsorbent in the form of a carbonized material. Waste newspaper was carbonized for 2 h in the temperature range 400°–1000°C. The specific surface area of the carbonized material obtained, 418 m²/g, was highest for the sample carbonized at 800°C, which was equal to or greater than that of commercially available charcoal. Moreover, the iodine adsorption number of 581 mg/g was the highest and the rate of adsorption was the fastest for the sample carbonized at 800°C. However, the humidity control capability was highest for the material carbonized at 600°–700°C. It has been determined that it is advantageous to carbonize waste paper at 800°C in order to use the carbonized material as an adsorbent, while carbonization at 600°–700°C is more advantageous for use as a humidity control material. Received: June 23, 2000 / Accepted: January 17, 2001     

Material cycle, waste disposal, and recycling in a Leontief–Sraffa–von Neumann economy

The purpose of this paper is to analyze problems concerning household waste disposal and material flow by means of a Leontief–Sraffa–von Neumann framework. We treat household residuals as if they were traded and valued in a daily market transaction. Thus, we can calculate the shadow price of waste, making a value system compatible with a quantity system. We show the theoretical existence of an equilibrium solution between a value system and a quantity system. This means that if there is a well-organized market for waste treatment, the flow of waste is smoothly regulated by a price adjustment mechanism. Household residuals are shown to be negatively valued if a certain constraint is satisfied. Thus, those residuals are bads instead of goods. Interestingly enough, household waste treatment in the market does not affect the price formation of normal commodities, since waste treatment services or recycling services are nonbasics in Sraffa's sense. Partly due to this character, the Hawkins–Simon condition is required only for normal production sectors, and not for recycling sectors. In the final section, we have dropped the assumption that household residuals are always treated as waste, since some residuals may be traded as normal commodities. Applying the Gale–Nikaido–Debreu lemma to a newly defined excess demand function, we have proved that our model can accommodate such a situation. By this analysis, we have shown that the goods/bads (waste) relationship is a relative matter, being dependent upon economic conditions. The changes in demand for, or supply of, residuals may turn some goods into bads, and vice versa. Received: October 5, 1999 / Accepted: October 18, 1999     

Mass balance of arsenic and antimony in municipal waste incinerators

The arsenic and antimony balance in two municipal waste incinerators was investigated. Initially, the production rates of ash and wet scrubber effluent were estimated. Then the arsenic and antimony in the ash and wet scrubber effluent were determined, which gave an estimate of the elemental balance. The total amounts of arsenic and antimony in the municipal waste were 0.9 g/t and 30–44 g/t, respectively. The distributions to fly ash were 45–47% and 33–74% for arsenic and antimony, respectively. The distribution mechanisms of arsenic and antimony are discussed from the viewpoints of their thermodynamics as well as their initial valencies, which greatly affect their behaviour. Received: July 2, 1998 / Accepted: February 27, 1999     

The German packaging ordinance: the questionable effects of a fragmentary solid waste management approach

Germany seems to be one of the leading nations in solid waste management, especially in the case of packaging waste; success stories about the ongoing increase in recycling strengthen this impression. However, enormous costs and questionable ecological benefits are the result of Germany's packaging ordinance and the formation of the recycling organization Duales System Deutschland (DSD). This article shows that similar progress in the reduction and recycling of packaging could have been realized without the packaging ordinance and dual system, with lower costs. This regulatory impact analysis of the German packaging ordinance covers all the effects on the different life-cycle stages of packaging, from production to recycling or disposal. The conclusion is that a fragmentary solid waste management approach – one that is based, like the German packaging ordinance, more on ideology than on facts – leads to enormous costs and questionable ecological benefits. To improve this situation, there is a need for an integrated solid waste management approach, based on evaluation of the economic, environmental, and social effects of different waste management options for the materials involved. Received: February 4, 1999 / Accepted: April 30, 1999     

Survey on the status of imported wastes used as raw material in China

 A survey was conducted on the status of imported waste steel–iron scrap and paper–cardboard, and their environmental impacts were analyzed based on the survey results. It was concluded that the importation of wastes will continue, and that it can be helpful to meet the steel–iron and paper-market demands. Some suggestions are offered to address these issues. Received: May 1, 2001 / Accepted: October 1, 2001     

Conventional and alternative technologies for the treatment of infectious waste

 The limited scientific information about infectious waste, and the heightened public awareness of this special component of the waste stream, have contributed to the implementation or strengthening of the regulations in this area. This paper proposes a general working definition of infectious waste, and describes the systems used to limit its potential occupational and public health impacts. Although incineration and autoclaving are the most widely used methods of treating infectious waste, the introduction of more stringent air-quality standards for incinerators, and the inherent limitations to the application of autoclaves, have created a demand for other methods of processing this segment of the solid and liquid waste streams. These alternative technologies use one or more of the following methods: (1) heating the waste to a minimum of 90–95°C; (2) exposing the waste to suitable chemicals; (3) subjecting the waste to heated chemicals; (4) irradiating the infectious waste with ionizing sources. The advantages and disadvantages of each of these alternative forms of treatment are discussed in this paper. Received: April 22, 2002 / Accepted: October 14, 2002     

Facilitating the improved management of waste in South Africa through a national waste information system

Developing a waste information system (WIS) for a country is more than just about collecting routine data on waste; it is about facilitating the improved management of waste by providing timely, reliable information to the relevant role-players. It is a means of supporting the waste governance challenges facing South Africa - challenges ranging from strategic waste management issues at national government to basic operational challenges at local government. The paper addresses two hypotheses. The first is that the identified needs of government can provide a platform from which to design a national WIS framework for a developing country such as South Africa, and the second is that the needs for waste information reflect greater, currently unfulfilled challenges in the sustainable management of waste. Through a participatory needs analysis process, it is shown that waste information is needed by the three spheres of government, to support amongst others, informed planning and decision-making, compliance monitoring and enforcement, community participation through public access to information, human, infrastructure and financial resource management and policy development. These needs for waste information correspond closely with key waste management challenges currently facing the country. A shift in governments approach to waste, in line with national and international policy, is evident from identified current and future waste information needs. However, the need for information on landfilling remains entrenched within government, possibly due to the poor compliance of landfill sites in South Africa and the problems around the illegal disposal of both general and hazardous waste.     

Distribution of organophosphoric acid triesters between water and sediment at a sea-based solid waste disposal site

Organophosphoric acid triester (OPE) concentration levels in water and bottom sediment at the Osaka North Port Sea-Based Solid Waste Disposal Site were investigated, and the behavior of OPEs in the water environment of the waste disposal site was examined. The more highly water-soluble OPEs were frequently detected in raw water. Of the OPEs detected, TCEP and TCPP showed very high concentrations (1.0–90 μg/l), followed by TEP (0.3–10 μg/l) > TBXP (0.8–6.3 μg/l) > TDCPP (0.6–6.2 μg/l) > TBP (0.2–1.5 μg/l) > TPP (<0.1 μg/l). Most OPEs detected in water were eluted from the disposal waste to the water phase immediately and behaved as dissolved forms with no distribution in suspended solids (SS). On the other hand, the less water-soluble OPEs, such as TCP or TEHP, were detected in bottom sediment but hardly at all in water samples. All OPEs were detected at the waste disposal site, within which their concentration levels were uniform. It appeared that the less water-soluble OPEs were present as SS-associated forms and behaved in line with the floating surface sludge at the bottom. Received: July 6, 1998 / Accepted: February 25, 1999     

The influence of sodium on biohydrogen production from food waste by anaerobic fermentation

Anaerobic fermentation of food waste for hydrogen production was performed in serum bottles with various linear alkylbenzene sulfonate (LAS) dosages (7.1–21.4 g/l) and sodium concentrations (5.03–28.7 g/l). LAS can effectively inhibit the activity of hydrogen-consuming bacteria, and the maximum hydrogen yield of 109.2 ml/g volatile solid (VS) was obtained at an LAS dosage of 14.3 g/l without added sodium. The feasible pH for hydrogen production is 5.0–6.0, and the process will slow down or stop when the pH is below 5.0.The hydrogen production potential increased when the sodium concentration increased in the range 5.03–14.41 g/l. The maximum hydrogen yield was 154.8 ml/g VS, and then the hydrogen production began to decrease when the sodium concentration increased further. A sodium chloride concentration of 20 g/l and higher will enhance the osmotic pressure and make bacteria inert. In the effluent, acetic acid is the major by-product. The results indicated that the hydrogen production from the anaerobic fermentation of food waste could clearly be increased with the additives and a sodium concentration less than 20 g/l.     

International comparative study of 3R and waste management policy developments

Reduce, reuse, and recycle (3R) policies form the basis of waste management and global warming countermeasures globally, so we conducted a comparative study of 3R and waste management policies in the European Union (EU), USA, Korea, Japan, China, and Vietnam. An international workshop for 3R and waste management policymakers was held in Kyoto, Japan, and a bibliographic survey was also conducted to collect data. 3R policies are clearly given priority in the hierarchy of waste management in every country studied. Thermal recovery, which includes power generation from waste heat and methane gas collected from organic waste, is also a priority; this is consistent with the increased use of countermeasures to reduce greenhouse gas (GHG) emissions. In the EU, waste management is characterized by practical and effective 3R policies through the development of realistic regulations and by the policymakers??desire to simplify management systems. The policy ideal in China, however, is the development of a circular economy that targets reductions in the amount and hazardousness of waste. Limits on the number of final disposal sites, strategies for procuring resources, and GHG emission countermeasures are closely linked with 3R policies, and further development of 3R policies in parallel with such issues is expected.     

Thermal decomposition of guaiacol in sub- and supercritical water and its kinetic analysis

The conversion of biomass waste into resources as a recycling process is receiving increased interest due to the perceived need for a sustainable global carbon cycle and environmental considerations. Several treatment processes are being developed. Hydrothermal treatment is one of the most effective approaches, because water at high temperatures and high pressures behaves as a reaction medium with remarkable properties. In this work, the reaction behavior of guaiacol as a biomass model compound was studied in subcritical water at 483–563 K and in supercritical water at 653–673 K using a batch reactor. Guaiacol can be considered representative of the aromatic ring structures present in lignin, a major component of woody biomass. The chemical species formed in aqueous products were identified by gas chromatography/mass spectrometry and quantified using high-performance liquid chromatography. The effect of pressure and reaction time on the conversion process of guaiacol is discussed. The results obtained indicate that this method has potential for efficient organic waste conversion.     

Emission inventory of deca-brominated diphenyl ether (DBDE) in Japan

Atmospheric emissions of deca-brominated diphenyl ether (DBDE) in Japan were estimated based on the material flow of DBDE products and their emission factors. In 2002, the demand for DBDE in Japan was 2200 ton/year and the stock level was about 60 000 ton. The DBDE flow into the waste stream was estimated to be about 6000 ton/year and the flow out through second-hand product exports was more than 700 ton/year. Home appliance recycling facilities dismantle and crush domestic wastes containing about 600 ton of DBDE annually. Material recycling of crushed plastics is not commonly practiced as yet. Emission factors from plastics processing (2 × 10⁻⁹–1 × 10⁻⁷), textile processing (9 × 10⁻⁷), home appliance recycling (8 × 10⁻⁹–5 × 10⁻⁶), and waste incineration (1 × 10⁻⁷–2 × 10⁻⁶) were estimated using field measurement data. The DBDE emission rate through house dust during the service life of final products (2 × 10⁻⁷–9 × 10⁻⁷ per year) was estimated using the DBDE concentration in dust and the amount of dust in used televisions. Emission factors from previous studies were also used. The estimated total DBDE emission was 170–1800 kg/year. These results suggest the necessity of characterizing emissions during the service life of products, which is essential information for formulating an appropriate e-waste recycling strategy.     

Characteristics of products and PCDD/DF emissions from a pyrolysis process of urethane/styrofoam waste from electrical home appliances

A plastic fraction consisting mainly of polyurethane/styrofoam waste is generated after separating valuable spare parts and metals from used electrical home appliances. In Korea, such waste is currently incinerated in cement kilns or is landfilled. However, owing to its high volatile matter content, conversion into gaseous or liquid pyrolysis products is a preferable alternative. A pyrolysis process of polyurethane and styrofoam waste from electrical home appliances was evaluated by characterizing the products generated at 500°–800°C. The para meters determined were the yields of gas, oil, and char; the characteristics of the remaining char; and the con centration of polychlorinated dibenzo-p-dioxins/polychlorinated dibenzo-furans in the product gas. As expected, the char yield decreased at higher temperatures, whereas gas and oil yields showed increasing tendency. The oil products could be used as storable fuels with a calorific value of 6000–8000 kcal/kg. Fine pores were observed in the char. The adsorption and decolorizing ability of the char were almost the same as those of activated carbon, so that pyrolysis char has potential for use as a sorbent. Further feasibility studies will be needed before utilizing pyrolysis technology to recover either fuels or usable products from polyurethane/styrofoam waste.     

Studies on the pyrolysis behavior of gasification and melting systems for municipal solid waste

 It is important to investigate the pyrolysis processes of municipal solid waste (MSW) in the same way as for any mixture comprised of multiple substances. In this article, a two-reaction model for a variety of MSW mixtures is proposed to predict mass changes due to pyrolysis. In order to formulate the model based on pyrolysis kinetics, we conducted experiments to determine the kinetic model parameters. By thermal analysis of the typical components of MSW, mass changes attributable to the pyrolysis reaction were found at about 350°C for paper, 400°–500°C for plastics, and 200°–400°C for garbage (dry condition). Activation energies were obtained by the Ozawa method based on the mass changes in pyrolysis. Thus, the pyrolysis behavior is formulated as a function of temperature. Then the pyrolysis mass change of the mixture can be predicted by using a weighted sum of the individual components. The model proved useful in experiments with real waste (refuse-derived fuels). Furthermore, the weight yields (pyrolysis gas, tars, solid residues) of the mixture can be calculated by their additive property after measuring the mass balance of each component. Received: May 11, 2001 / Accepted: November 16, 2001     

Adhesion Properties of Adhesive Prepared from Waste Polystyrene

Solid and soft forms of waste polystyrene have been treated with coumarone–indene resin and benzene to produce a new adhesive. The adhesive is prepared from various compositions of polystyrene (13–38 wt%), coumarone-indene resin (5–7%) and benzene (57–80%). Viscosity, peel strength and tensile shear strength of the adhesive is determined by a HAAKE Rotary Viscometer, Lloyd Adhesion Tester and Instron machine, respectively. Rolling ball technique was used to measure the tackiness of the adhesive. Results show that the adhesion property increases with increase in polystyrene composition and coating thickness. This observation is attributed to the increasing wettability of adhesive on the substrate.     

Biohydrogen using leachate from an industrial waste landfill as inoculum

Since hydrogen is a renewable energy source, biohydrogen has been researched in recent years. However, data on hydrogen fermentation by a leachate from a waste landfill as inoculum are scarce. We investigated hydrogen production using a leachate from an industrial waste landfill in Kanagawa Prefecture. The results showed no methane gas production, and the leachate was a suitable inoculum for hydrogen fermentation. The maximum H₂ yield was 2.67 mol of H₂ per mol of carbohydrate added, obtained at 30°C and an initial pH of 7. The acetate and butyrate production was significant when the H₂ yield was higher. Oxidation–reduction potential analysis of the culture suggested that hydrogen-producing bacteria in the leachate were facultative anaerobic. Scanning electron microscope observations revealed that the hydrogen-producing bacteria comprised bacilli about 2 μm in length.     

Using research-based knowledge to underpin waste and resources policy.

The concept of a knowledge-based approach to policy making (also referred to as 'evidence-based policy making' or 'science meets policy') has been around for 10 years, and is widely 'signed up to' by Governments. This paper examines the theory and the practice at national government (using the UK as a case study) and European levels, looking at how the knowledge-based approach has been applied in waste and resources management. There is general agreement that a knowledge-(or evidence-) based approach to policy making is a 'good thing'; however putting the concept into practice has proven challenging and is still evolving. The linkages between researchers and policy makers need to be further strengthened, as does the 'demand' for evidence from policy; requiring policy specialists to articulate their requirements for evidence sufficiently well in advance, and to do so routinely, is still an area of weakness. Using a model developed by the UK's Department for Environment, Food and Rural Affairs (Defra), we examine in detail some of the implications of changing the question from 'is this good research on waste and resources issues?' to 'is this good evidence for waste and resources policy?'. The paper also provides recommendations for further work required to achieve this at a European level, and for priority areas where international co-ordination of waste and resources research could add most value to policy.