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Unmaking  Waste  2015  Conference  Proceedings  22  –  24  May  2015  Adelaide,  South  Australia  

Solutions for solid wastes

Session 11

Biosolids: Policies, Perception and Potential for Beneficial Use – Norman (Chin How) GOH, Michael D. SHORT, Nanthi S. BOLAN, and Christopher P. SAINT

The economic and bio-energy production potential of South Australian food waste using Anaerobic digestion – Atiq ZAMAN and Christian REYNOLDS

Current State of Scrap Utilization by Thai SMEs – Singh INTRACHOOTO

 

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Unmaking  Waste  2015  Conference  Proceedings  22  –  24  May  2015  Adelaide,  South  Australia  

Biosolids: Policies, Perception and Potential for Beneficial Use

Norman (Chin How) GOH1, Michael D. SHORT1, Nanthi S. BOLAN2, and Christopher P. SAINT1

1. Centre for Water Management and Reuse, School of Natural and Built Environments, University of South Australia, Mawson Lakes Campus, SA 5095, Australia

2. Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes Campus, SA 5095, Australia

Biosolids management and reuse

In recent years, there has been an appreciable shift in attitude to biosolids management, with biosolids now considered as a resource with potential marketability and opportunities for beneficial reuse, rather than a waste product requiring disposal (EPA SA 2009, UNEP 2002). This paradigm shift has been spurred on by rising fertiliser and commodity prices, as well as the scarcity of affordable land and environmental penalties for emissions from landfilling and improper disposal (ABARES 2010, Ministry for the Environment 2008, Council of the European Union 1999).

Recent research has suggested that biosolids have the potential to sequester carbon when applied to land and may contribute to climate change mitigation (Lal 2004, Tian et al. 2009, Smith et al. 1997). This is especially relevant in Australia, where the dry climate, carbon-poor soils and large areas of land may be well suited to carbon sequestration (Bolan et al. 2012, Sanderman, Farquharson, and Baldock 2009, McLaughlin et al. 2007, Pritchard et al. 2010). Furthermore, the Carbon Farming Initiative — the cornerstone of the Australian Federal Government’s ‘direct action’ climate policy — adds a structured dimension and the potential of financial incentive to the discussion.

This paper provides an overview of current biosolids use practices in Australia, critiques carbon sequestration policy surrounding biosolids, and highlights the present and future risks and opportunities for the water sector in biosolids management and end-use.

Keywords: Biosolids reuse; Carbon policy

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Introduction

Biosolids are the solid end-product generated by all wastewater treatment plants (WWTPs). Consisting mainly of water, organic matter, nutrients and trace chemicals, once processed and stabilised, biosolids become available for reuse. Biosolids production continues to increase globally due to requirements for more advanced wastewater treatment and growing global populations (ANZBP 2012, Goodman and Goodman 2006, Spinosa and Vesilind 2001). In the EU alone, sludge production doubled from 1992 to 2002 and is currently well above eight million tons of sludge (dry wt.) annually (Evans 2012, NZWWA 2003, Spinosa and Vesilind 2001).

Historically, the value of biosolids was often overlooked, despite recognition of the high carbon and nutrient contents and significant fuel potential (Hurwitz and Dundas 1960, Sommers 1977, Clapp et al. 1986, Smith and Peterson 1982, UNEP 2002). For decades since the advent of modern wastewater treatment, biosolids was regarded as a waste material. Progressive moves toward more stringent environmental legislation and regulations have since forced water utilities and municipalities away from traditional means of disposal such as ocean dumping and landfilling, towards more ‘beneficial’ end-use alternatives (UNEP 2002, ANZBP 2012).

Typically, the hierarchy of waste management is reduction, followed by reuse, recycling, energy recovery and finally safe disposal as a last resort (IPCC 2014). Legislation for biosolids management is structured in this manner and reflects public perception and cultural attitudes towards biosolids reuse (Spinosa and Vesilind 2001). In the US, the 1993 US EPA Regulation 503 is aimed at facilitating the beneficial reuse of biosolids to land, whereas in the EU, a more precautionary approach has been adopted with the Directive 86/278/EEC (O'Dette 1998, Directive 1986). Australian national guidelines are based on the more conservative European approach; although much of the scientific work is based on the more recent US studies (Darvodelsky 2012). Additionally, each state already has or is currently developing independent biosolids guidelines which regulate best practice requirements for beneficial reuse.

Industry: Policy and Perceptions

Biosolids in Australia: Current state of play

Australia currently produces approximately 330,000 dry tons of biosolids annually with varying rates of production distributed across the states roughly in proportion to the population size (see Table 1).

Common industry practice sees biosolids stockpiled on-site for years prior to being reused where land is available. In South Australia, processed biosolids are stockpiled for a minimum of three years for pathogen inactivation and further drying prior to use on broadacre farms as a free substitute for synthetic fertilisers (Makestas 2013). The practice of stockpiling is also prevalent in Tasmania, the Northern Territory and Victoria to varying degrees. In Victoria, three million cubic metres of biosolids estimated to be at least 30 years of Victorian biosolids at current production rates (or equal to 10 years of current national production) is stockpiled (Melbourne Water Corporation 2015, ANZBP 2012). Distributed between Melbourne Water Corporation’s Eastern and Western Treatment Plants, much of the stored biosolids is legacy material and too highly contaminated to be reused under current environmental guidelines. However, research is being funded by Melbourne Water Corporation into exploring technologies and markets to treat this legacy material and facilitate the beneficial reuse of biosolids (Melbourne Water Corporation 2015). Currently, with improvements to source control

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and treatment processes, the biosolids being produced is of significantly better quality and is being utilised in agricultural and forestry applications in line with the rest of the country. The situation is much the same in Tasmania and the Northern Territory with stockpiling as the interim strategy of management as landfilling is phased out for the increasing adoption of agricultural land application (OTTER 2014).

Table 1: Australian biosolids production in 2013 [adapted from (ANZBP 2013) and (Australian Bureau of Statistics 2013)]

In Western Australia, Queensland and New South Wales, dewatered biosolids are mostly applied directly to land in broadacre farming (Water Corporation of WA 2015, Sydney Water Corporation 2012, Kronk 2013). Private contractors also compost a significant portion of the bisolids in Western Australia and New South Wales to produce marketeable agicultural compost products. Additionally, some biosolids are utilised in forestry applications and for mine site rehabilitation. In 2007, research was conducted into mixing lime-amended biosolids from Subiaco WWTP in Western Australia with clay to produce Lime-amended BioClay (LaBC®). Trials showed that in addition to neutralising acidity, LaBC® has reduced leaching of nutrients, reduces soil water repellence and increases water retention in sandy soils (Shanmugam, Abbott, and Murphy 2014). Wide scale application of this product began in 2011 and is currently ongoing. In NSW, Burwood Beach WWTP operated by Hunter Water Corporation still discharges biosolids into the ocean (Consulting Environmental Engineers 2007, Sydney Water Corporation 2012). However, this process is currently being reviewed and may potentially be revised to beneficially reuse biosolids on land (Hunter Water Corporation 2011).

Unlike the rest of the country, the  Australian Capital Territory (ACT) is the only region in Australia that practises the incineration of biosolids. In operation since 1978, all dewatered biosolids produced at the Lower Molonglo Water Quality Control Centre are incinerated and the resulting pelletised ash product (Agri-Ash) is sold to farmers (ACTEW Corporation 2014). At 6.6% phosphate content and 60% the neutralising value of lime, Agri-Ash has proven a viable alternative fertiliser in the wake of fluctuating synthetic fertiliser prices (Fertspread 2013, NSW Department of Primary Industries 2012). Currently, with the projected population growth in Canberra, the incineration facility in the ACT is forecast to have sufficient capacity until well beyond 2060 (ACTEW Corporation 2010).

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Figure 1: Biosolids end-use in Australia [adapted from (ANZBP 2013)

Carbon emissions policy in Australia: Past, present and future

Australia’s journey to a low carbon economy began in 2007 with the ratification of the Kyoto Protocol and the introduction of the National Greenhouse and Energy Reporting (NGER) Act. Under the NGER scheme, emissions reporting became mandatory and with the inception of the Clean Energy Act in 2011, a national price on greenhouse gas (GHG) emissions was introduced. Facilities with annual emissions above the 25,000 tons carbon dioxide equivalence (CO2-eq) threshold would be required to pay AUD$23/ton CO2-eq in 2012 with the price increasing at 2.5% annually as part of the Carbon Pricing Mechanism (CPM) (Clean Energy Act 2011, NGER 2007). Recently, this tax-based system for emissions abatement was replaced with an incentive based system called the Direct Action Policy. This new policy expands upon the Carbon Credits (Carbon Farming Initiative) Act introduced in 2011 and allows participants to generate Australian Carbon Credit Units by sequestering carbon or conducting activities that reduce GHG emissions. In 2014, the Carbon Farming Initiative Amendment Bill was passed, allowing the establishment of an AUD$2.55 billion Emission Reduction Fund to finance the new  emissions abatement strategy. Initially, under the former CPM, Australia would link up with the EU Emissions Trading Scheme (ETS) in 2015, allowing for carbon trading between Australian and European counterparts (European Commission 2014). With the 2014 repeal of the Clean Energy Act 2011, this proposal is now on hold but may still eventuate within the prearranged 2015–2018 timeframe (Kossoy 2013). Inevitably, an ETS will be adopted in Australia as there is significant political support federally with some proponents favouring the transition to an ETS sooner rather than later.

The carbon debate presents an interesting policy dimension to the management of biosolids. Contrary to the conventional wisdom that ‘going green’ will result in a financial burden, investing in low-carbon technologies and de-carbonising the economy can be a viable solution for modern day economic growth (Molitor 2014). Pricing mechanisms on carbon emissions, incentives for renewables and penalties for pollution have in fact driven organisations to increase their levels of efficiency and overall become more financially sustainable (Molitor 2014). Investments in green energy and renewable technologies have grown immensely in recent years and this is no exception in Australia. A number of municipalities and water utilities such as the City of Melbourne and Sydney Water Corporation have pledged voluntary commitments to achieve ‘carbon neutrality’ in their operations (Sydney Water Corporation 2014, City of

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Melbourne 2014). Furthermore, the institution of fixed government policy can present an additional level of certainty to the realisation of carbon emissions abatement through biosolids reuse, and the effect of carbon policy on industry practice has already been demonstrated with the former CPM. For example, recent Australian research reported that electricity demand declined nationally by 3.8% during the 1 July 2012 to 30 June 2014 CPM period, resulting in an 8.2% cut in emissions (O'Gorman and Jotzo 2014). Similarly, The Age reported that electricity production using brown and black coal decreased by 14% and 4.7% respectively during the operational lifespan of the CPM, with renewable energy and lower-emissions gas power increasing by 28% and 9.5% respectively during the same period (Arup 2013).

With its inherently high carbon and energy content, significant levels of macro and micro nutrients, and the already well-established practice of agricultural application, a multitude of options exist for beneficial biosolids reuse. Nonetheless, consolidation of reuse options is always promoted by utilities, and with the new Direct Action Policy, biosolids have the potential to be aggregated into the existing carbon crediting system with soil carbon sequestration being key to this new strategy. As a direct result, future reuse options for biosolids such as cropping for biofuels or large scale soil restoration utilising biochar for boosting carbon stocks maybe promoted to exploit carbon credit revenue streams. There are currently a total of 201 projects worth AUD$139.59 million being funded as part of the Carbon Farming Futures program exploring GHG emissions reduction and carbon sequestration opportunities throughout Australia (Department of Agriculture 2014).

Prospective outlook for beneficial reuse

It seems likely an ETS will be introduced in Australia in the future in conjunction with the Carbon Farming Initiative. In light of this, local utilities are already investing in projects to investigate GHG emissions and energy reduction to optimise existing assets and minimise future business risks and liabilities linked to their operations. For Australian biosolids, there is significant potential to alter the current standing of this material from a potential liability to a prospective asset. Globally, technologies such as biochar, energy generation, biofuel production and nutrient extraction from sludge have been researched for years, and with the recent onset of various national ETS programs, these research areas are gaining financial traction in industry. The situation is likely to be similar in Australia.

In recent years, the potential of carbon sequestration to soils as a viable method of carbon capture and storage has been widely discussed. The application of biochar to soils is becoming more widely researched with the effectiveness of soil carbon sequestration expected to be significantly improved in geologically old and carbon-poor soils such as those prevalent throughout Australia. Additionally, the sheer vastness of land available in Australia has made soil carbon sequestration an attractive option for climate change mitigation at the national level. Biochar production from biosolids is technically feasible utilising existing pyrolysis technology; however, economic limitations including the lack of a significant market for biosolids-derived biochar and uncertainty surrounding long-term carbon policy has limited investment in this technology. Regardless of political uncertainty, a number of government and industry bodies are now actively researching the viability of biochar as a value-added biosolids product.

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With the inherent nutrient content of biosolids, it has long been proposed that biosolids be used to grow biofuel crops, with carbon credits being accrued from both fertiliser and fuel offsets. For example, in Sunnyside, Washington, USA, a study was comissioned to assess the feasibility of growing canola using biosolids, with farmers successfully involved in selling canola oil to Imperium Renewables in Seattle for the production of biodiesel (Kalogo and Monteith 2008, Brown and Leonard 2004, Natural Selection Farms Inc. 2010). By the same token, studies have been conducted into biosolids conversion directly into fuel. The first commercial demonstration plant of EnerSludge™, a sludge-to-oil process, was constructed and run at the Subiaco WWTP in Perth some 15 years ago. Although there were positive energy returns and the process was shown to be technically and commercially feasible, the project was ultimately discontinued after 16 months of operation in favour of more cost-effective lime amendment (Kalogo and Monteith 2008, Spinosa 2011). Despite this, with the general trend of rising fossil fuel prices and the progressive global shift to a low carbon economy, it is likely that such a technology will make inroads into mainstream biosolids processing in the future.

Phosphorous is one of the most valuable global commodities for cultivating crops to feed our growing population and exists in significant concentrations in biosolids. With finite mineable reserves limited to only a few countries and estimated at only 300–400 years of material remaining at current rates of production, the prices of various mineral fertilisers have risen significantly, peaking in 2008–09 with some products more than doubling from 2006–07 prices (ABARES 2010, Van Kauwenbergh 2010). Between 1–3g of phosphorous is excreted per person into the wastewater system every day, amounting to a global production of some 2.6–8 million tons of phosphorous annually (Henze and Comeau 2008). In light of this, it has been proposed that chemical precipitation or enhanced biological recovery of phosphorous from wastewater streams be employed. Utilising the latter, up to 95% of phosphorous in sewage can be concentrated in biosolids (Kalogo and Monteith 2008). In Canada, a chemical precipitation method utilising magnesium chloride (designated the Pearl® Process) treats 25% of the supernatant from the City of Edmonton’s WWTP and has been producing 250 million tons of struvite per annum since 2007 (Kalogo and Monteith 2008). Current economics limits the wide-scale application of such recovery technologies, but research is being actively conducted worldwide.

There has long been strong interest in utilising biosolids in the area of construction, particularly in Asia (Spinosa 2011). Japan currently utilises a large proportion of their carbonised biosolids in the production of Portland cement, exceeding that of agricultural application (Spinosa 2011, Spinosa and Vesilind 2001, Kalogo and Monteith 2008, Taruya, Okuno, and Kanaya 2002). Other industrial materials produced include bricks, slag, artificial lightweight aggregates and pumice, with full-scale plants having been in operation since the 1990s (Kalogo and Monteith 2008). China and South Korea are currently researching this pathway for biosolids reuse with incineration and co-production plants being planned for development in both countries (Spinosa 2011). In 2005 in Australia, research was conducted into the suitability of utilising biosolids as feed material for the production of bricks and pavers, and although the project was able to manufacture bricks of adequate strength (which also passed EPA toxicity requirements), durability was found to be an issue with the product (Smart Water Fund 2005). On top of that, there was not a market at the time accepting of biosolids-derived building material (Smart Water Fund 2005). Further research is required to further explore and develop this technology. In 2009, a separate project investigating the suitability of biosolids as fill in road embankments was undertaken with very positive results (Smart Water Fund 2009).

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Although not popular in Australia, incineration has been widely adopted in the US and the EU as a biosolids management strategy (Strande, Ronteltap, and Brdjanovic 2014) as utilities continue to seek alternatives to land application and as technological advances improve combustion efficiency. Where land application is not practical, the direct combustion of biosolids can generate positive energy returns with co-combustion of other waste or fuel material, making the process more efficient and economically feasible (Wang et al. 2008). Japan and South Korea currently practise incineration of biosolids due to the lack of land and China is looking to build more incineration plants to manage the increasing amount of sludge being produced by its growing population. The resulting ash from incineration can either undergo further phosphorous or metals extraction, be utilised as a liming agent in agriculture and also as a feedstock for cement production (Strande, Ronteltap, and Brdjanovic 2014, Taruya, Okuno, and Kanaya 2002). As previously mentioned, there is only one incineration facility currently in operation in Australia and it is expected that this will remain the case for the immediate future due to budgetary restrictions facing Australian utilities and the high associated capital and operational cost.

Conclusion

Current options for beneficial reuse of biosolids in Australia are largely centred on agricultural land application and the rehabilitation of degraded soils. However, with the depletion of natural phosphate reserves, volatility of fossil fuels prices and the global shift toward a low carbon economy, the diversification of technologies and options for the beneficial reuse of biosolids in Australia is expected to grow. Globally, the trend of biosolids reuse in mature markets is leaning towards nutrient extraction and power generation as witnessed in the US and the EU. Upcoming economies such as China and India are only starting to grapple with the issue of biosolids management and much of the developing world is still oriented towards the established practice of land application. Australia sits somewhere in the middle and the way forward for future biosolids management in Australia will largely be driven by economics, technological development, public perceptions and market demands.

With an increasing global emphasis on environmental sustainability, the influence of ‘green’ policies and decision making on the practices of global industries will increase. The introduction of low carbon economy-based policies in Australia and around the world has the potential to facilitate the adoption of carbon crediting technologies in biosolids management, with research in this area currently underway amidst the global shift away from fossil-based energy technologies. The increasing public demand for ‘green alternatives’ echoes this new norm and in doing so facilitates the change in perception of biosolids from a waste product to a potential resource. In future, it may eventually be possible for biosolids to be traded as a commodity for the inherent nutrient, carbon and energy value. However, whether or not and when this occurs will depend on global and national policy and its role in facilitating the successful global transition to a low carbon economy. The water sector would do well to invest early in biosolids reuse, concurring with the growing public desire for ‘green alternatives’ and be proactive on the quest of ‘unmaking waste’.

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Acknowledgements

Chin How Goh is a recipient of a CRC for Low Carbon Living Scholarship as part of research project  RP2008: Beneficial Reuse of Solids from Wastewater Treatment Operations. A number of Australian water utility and government departmental representatives across Australia have contributed information to this paper and the authors acknowledge and thank them for their contribution.

 

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Unmaking  Waste  2015  Conference  Proceedings  22  –  24  May  2015  Adelaide,  South  Australia    

The economic and bio-energy production potential of South Australian food waste using Anaerobic digestion Atiq ZAMAN and Christian REYNOLDS

University of South Australia, Australia

Australia is one of the highest food waste generating countries in the world per head of population with over 7.3 million tonnes of food waste generated in Australia in 2008. Anaerobic digestion (AD) is a promising and environmentally sustainable organic waste treatment technology which digests organic waste into a stabilise residue and generate biogas, which can be used to produce energy. Despite large-scale application of AD in the USA and Europe, AD has not been applied widely in Australia. This paper investigates the challenges and opportunities of managing organic waste in South Australia using AD. Following a comprehensive literature review of AD technologies in relation to challenges, barriers and scope of implication in the global context, the study forecast the bio-energy production potential in South Australia using AD. This paper finds that the small AD plant could generate 39kWh from around 589 tonnes of food waste annually. The study also forecast the bio-energy potential by 2021 and if 15% of South Australia’s food waste (of year 2021) were treated with AD, a 256kWh energy could be generated. The addition of poultry waste would dramatically increase the proposed plant size up to 3556kWh. This would be a large energy plant that would be a considerable contributor to the SA power grid, provide a level of SA energy security. The payback time for all plant sizes is between 2.5-3.5 years.

Keywords: organic waste, waste management, waste-to-energy, anaerobic digestion, renewable energy policy

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1. Introduction

Australia is one of the highest food-waste generating countries in the world per head of population (Mason, 2011) with over 7.3 million tonnes of food waste generated in Australia in 2008 (Reynolds et al 2014). A study shows that around 74% of total food was wasted in Sydney in 2009 before it reached the consumer - despite the fact that food waste was of edible quality (EPA-NSW, 2010).Organic waste such as food waste not only imposes risks on the global food security, but it also contributes Methane (CH4) and Nitrous Oxide (N2O), which have 21 and 310 times greater global warming potential respectively than carbon dioxide (IPCC, 1996). There are growing concerns about the economic and environmental variability of existing organic waste disposal systems.

According to the World Bank report, around 87% of waste sent to landfill or open dumping globally and based on organic contents, organic waste produces 300-1000kg of CO2 for every tonne of waste sent to landfills, therefore, it is estimated that the organic fraction of municipal solid waste (MSW) contributes approximately 0.2-0.6 billion tonnes of greenhouse gas (GHG) to the atmosphere every year (Manfredi et al. 2009, World Bank, 2012). Worldwide, CH4 emissions from the waste sector constitute approximately 18% of the global anthropogenic CH4 emissions (Scheutz et al., 2009). GHG emissions reduction to the atmosphere is one of the key challenges and priority actions against climate change around the globe. Biofuel technologies use waste feedstock from various sources, including wood from forest industry, biomass from agriculture and poultry industries and organic MSW to produce energy and fuels. Therefore, biofuel technologies, such as Anaerobic Digestion (AD), not only manage organic waste, but it is also produces energy and biofuels.

This study will examine the key issues, challenges and opportunities in implementing AD in South Australia, and act as a scoping study for the development of AD in South Australia. Section 2 consists of a literature review of AD technology; Section 3 discusses the economic and regulatory feasibility of AD deployment in South Australia. Finally, the study concludes by acknowledging the fundamental barriers and challenges of implementing AD in South Australia.

2. Review of Anaerobic digestion

Anaerobic digestion is a biological process to produce biogas from organic waste. Organic waste from farms, agricultural lands, households, food processing industries, meat and fish industries and other sources can be used in an anaerobic digester to produce biogas. Biogas is used to produce heat, electricity and biofuel. Figure-1 shows a simplified diagram of organic waste to bioenergy process.

Figure 1: A simplified diagram of organic waste to bio-energy using anaerobic digestion

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Biogas mainly consists of 50-75% methane, 25-45% carbon dioxide, 2-8% water vapour and traces of O2, N2, NH3, H2, H2S (Dimpl, 2010). A typical biogas composition can be found in the Sustainable Energy Development Authority's report into the potential for generating energy from wet waste streams in NSW (in Table 1).

Table 1: The composition of biogas (SEDA, 1999)

Components Content % (v/v)

Methane 52-95

Carbon dioxide 10-50

Hydrogen sulphide 0.001-2

Hydrogen 0.01-2

Nitrogen 0.1-4

Oxygen 0.02-6.5

Argon 0.001

Carbon monoxide 0.001-2

Ammonia trace

Organics trace

Anaerobic digestion is a series of four complex biological processes such as hydrolysis, acidification, acetogenesis and methanogenesis (Moriarty, 2013). Fermentative bacteria excrete exo-enzymes to transform the particulate organic substrate into liquefied monomers and polymers in hydrolysis (solubilisation) process (Ostrem, 2004). Hydrolysis is a relatively slow process and generally it limits the rate of the overall anaerobic digestion process. In acidogenesis (acidification) process, hydrolysed products are broken down into simple molecules and short chain volatile acids, ketones, alcohols, hydrogen and carbon dioxide (Ostrem, 2004). In the third step, acetogenesis, the products of the acidification are converted into acetic acids, hydrogen, and carbon dioxide by acetogenic bacteria. The first three steps of anaerobic digestion are often grouped together as acid fermentation. Hydrogen plays an important intermediary role in this process, as the reaction will only occur if the hydrogen partial pressure is low enough to thermodynamically allow the conversion of all the acids (Mata-Alvarez, 2003). Methanogenesis is the final step of the anaerobic digestion process where methanogens bacteria (microorganisms) convert the hydrogen and acetic acid formed by the acid formers to methane gas and carbon dioxide (Verma, 2002). Figure 2 shows the biological processes of AD.

Figure 2: Anaerobic digestion process (Moriarty, 2013)

Carbohydrate

Sugars

Proteins Amino Acids

Carbon Acids

Hydrogen Carbon Dioxide

Acetic Acid Carbon dioxide

BIOGAS (methane, carbon dioxide)

Fats Fatty Acids

HYDROLYSIS              ACIDOGENESIS              ACETOGENESIS          METHANOGENESIS  

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2.1. Gas yield and energy efficiency of anaerobic digestion

Biogas yield varies depending upon the composition of feedstock and the ambient conditions in the digester. Electricity and heat generation from biogas varies depending on the methane content of the biogas. It is estimated that 2kWh electricity and 2kWh heat can be generated from 1 cubic meter of biogas (55% CH4 content biogas, 20MJ/m3, 38% electrical and thermal efficiency CHP unit) (SEAI, 2010).

2.2. Benefits of AD

Anaerobic digestion offers multiple benefits. The broad range of benefits including social, environmental and economic benefits can be achieved from AD of organic waste. AD encourages local community to recycle organic waste and thus involves local people to the recycling activities. By managing organic waste in a sustainable way, AD solves waste problems as well as environmental problems, such as global warming. AD avoids and reduces GHG emissions to the atmosphere by utilizing biogas as a source of renewable energy. In addition, AD improves health and safety issues associated with pathogen spreading and protects from water and land pollutions. Most importantly, AD produces renewable bio-energy from waste and produces bio-fertilizers. Therefore, AD reduces the dependency on fossil fuels and inorganic fertilizer which is damaging to our environment. AD also creates jobs and business opportunities, though these are only quantifiable in a site specific context.

2.3. The state of anaerobic digestion in the global context

Anaerobic digestion is used for managing organic waste (including poultry and biomass) in both developed and developing countries, with the size of AD plants varying with local needs. In developing countries such as Bangladesh, India, Nepal and China, small scale anaerobic digestion plants are the norm, with the biogas that is produced mainly used for cooking purposes. Large scale AD plants feature in developed countries and are used to generate heat and electricity with combined heat and power facilities (Baker, 2014; Biogas-info, 2014; BRE-info, 2014; Biogaspedia, 2014; EPA, 2010). The annual capacity of the biggest energy plant from biomass (wood pallet) is 750MW and located in Tilbury, UK. In 2011, the UK also opened the largest anaerobic digestion plant using food scraps of 6MW electricity capacity (EurObserver, 2011; Waste Management World, 2011).

3. Feasibility of AD for managing organic waste in South Australia

3.1. Economic feasibility of AD

3.1.1. Biogas and energy potential in SA

In a pilot study in 2009-2010, conducted by the Zero Waste SA, 589 tonnes of food waste were collected from the 17,000 households’ green bin (34.7 kg/year/household) for processing and treatment (ZWSA, 2010a; ZWSA, 2010b). The environmental impacts of avoidance and composting of this food waste were explored in Reynolds et al (2011). With this pilot data, we forecast three separate scenarios of the biomass energy potential in SA. The first scenario examines the biomass energy generation potential from the South Australian food waste pilot study. The second scenario builds upon scenario one upgrading to a larger AD plant with the capacity to treat 15% (3877 tonnes) of South Australia’s total food waste. We sourced South Australian population

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data from the Australian Bureau of statistics (1999, 2011) – chiefly that in 2011 there were 643,886 households in South Australia; this is forecast to grow to 745,000 by 2021. The total projected food waste generation in South Australia by 2021 is 25,851 tonnes. The third scenario expands further with the introduction of co-digestion practices to incorporate 100% South Australian poultry/chicken waste into the AD waste stream.

3.1.2. Data assumptions

The food waste generation of 34.7 kg/year/household was sourced from Zero Waste SA reports (ZWSA, 2010a; ZWSA, 2010b). South Australian chicken and poultry waste generation (89,508 tonnes per year: 3508 tonnes of chicken carcasses, 16,380 tonnes of meat processing waste, and 69,620 tonnes of manure) was sourced from Environmental Protection Agency Reports (EPA-SA, 1999).

We sourced the biogas yield for food scraps, manure, and chicken waste as 265m3, 82m3 and 280m3 per tonne, from standard figures for biogas production (Biogasinfo 2014, Navaratnasamy et al 2008 ). Total AD energy generation potential was sourced from Navaratnasamy et al (2008), which detailed potential electricity generation at 2kWh per m3 of biogas (55% CH4 content biogas, 20 MJ/m3, 38% electrical and thermal efficiency CHP unit), with additional heat generation of 2 kWh per m3 of biogas or 7.7 MJ per m3 of biogas.

The 2011/12 average cost of electricity in South Australia was found to be 27.25 c/kWh, with the heat from natural gas costing 3.29 cents per MJ (Essential Services Commission of South Australia 2014). The cost of electricity has been forecast to increase past 28.6c/kWh by 2014, with the cost of gas remaining constant at 3 cents per MJ (Energy Users Association of Australia 2012, Australian Energy Market Operator 2013). We have selected 28.6c/kWh as our electricity price and 3 cents per MJ as our gas price.

Functional costs of running an AD operation were sourced from Navaratnasamy et al (2008), these include a 30 days per year maintenance shut down, and a starting capital cost of $7000 per kWh for construction of biogas electricity generating plant, and a further operational cost of $0.02/kWh. We also assume a 24 hour per day operation of the plant. Our assumptions are solely based on technological cost and revenue. We did not consider the biomass collection and transportation cost, or administration cost our scenario analysis. Inclusion of these factors would which increase investment will return time.

3.1.3. Energy from bio-waste scenarios in South Australia

The size of AD plant required to treat the volume of food waste collected in the pilot would be 39 kWh generating plant (scenario 1). The size of AD plant required to treat the 15% of the total food waste generated in SA (scenario 2) would be larger at 256kWh. The addition of poultry waste (scenario 3) would dramatically increase the proposed plant size to 3556kWh – a large plant that would be a considerable contributor to the SA power grid and provide a level of energy security to SA (Australian Energy Market Operator 2013). The payback time for all plant sizes is between 2.5-3.5 years depending on the inclusion of heat capture facilities.

The electricity produced in all these scenarios is suitable for small scale power plants compared to the existing power plants in South Australia, such as the Playford B Power Station that produces approximately 240 MW of electricity and the Torrens Island Power plant that produces 1280 MW of electricity (Australian Energy Market Operator

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2013). To be eligible for renewable energy target funds (RET), the energy plants needs to produce minimum 1MW of electricity, thus the scenario 1 and 2 would not be eligible for RET fund and only scenario 3 which is energy from co-digestion of animal fat, manure with household organic waste is eligible for RET fund and the most viable option is SA.

Scenario 1: Energy from food waste pilot

In scenario 1, the food waste collected in a pilot study conducted by the ZWSA in 2011 were considered and assumed to be homogeneous as they collected from organic bins and thus available for AD. Therefore, only 1700 households were considered for scenario 1 (in Table 2).

Table 2: Scenario 1 - Energy from SA food waste pilot

Assumptions Food waste collected 589 tonne

Biogas yield 265 m3/tonne

Total biogas yield 156,085 m3

Electricity generation 2 kWh/m3

Heat generation 7.7 MJ/ m3 biogas

Total electricity generation 312,170 kWh

Total heat generation 1,201,854.5 MJ

Average cost of electricity 28.60 c/kWh

Average heat cost 3.00 c/ MJ

Total income from electricity $89,280.62  Total income from heat $36,055.64  Number of operating days 335 per year

Operational Hours 24.00 per day

Capacity of the electricity generator 38.83 kWh

Capital cost of plant $7,000.00 per kWh

Total capital cost $271,789.80  Operation cost $0.02 per kWh

Total operation cost $6,243.40 year

Total yearly revenue $119,092.86 a year (with heat capture facilities)

Total yearly revenue $83,037.22 a year (without heat capture facilities)

Scenario 2: Energy from projected food waste

In scenario 2 (in Table 3), the projected amount of available food waste in 2021 was considered. Only 15% of the projected food waste in South Australia was considered to estimate the potential energy from bio-waste in SA.

Table 3: Scenario 2 - Energy from 15% of SA food waste

Assumptions Food waste collected 3878 tonne

Biogas yield 265 m3/tonne

Total biogas yield 1,027,597 m3

Electricity generation 2 kWh/m3

Heat generation 8 MJ/m3 biogas

Total electricity generation 2,055,194 kWh

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Total heat generation 7,912,498 MJ

Average cost of electricity 29 c/kWh

Average heat cost 3 c/ MJ

Total income from electricity $587,785.56  Total income from heat $237,374.94  

Number of operating days 335 per year

Operational Hours 24.00 per day

Capacity of the electricity generator 256 kWh

Capital cost of plant $7,000.00 per kWh

Total capital cost $1,789,348.23  Operation cost $0.02 per kWh

Total operation cost $41,103.89 year

Total yearly revenue $784,056.61 a year (with heat capture facilities)

Total yearly revenue $546,681.67 a year (without heat capture facilities)

Scenario 3: Energy from projected food waste and poultry waste

In scenario 3 (in Table 4), a combined mixed feedstock, food waste and chicken and poultry waste were considered as there are several poultry processing plants in SA and chicken fats and poultry waste have higher biogas production yield.

Table 4: Scenario 3- Energy from 15% of SA food waste and poultry/chicken waste

Assumptions Chicken carcasses and meat

processing waste

19888 tonne

Chicken manure 69620 tonne

Food waste collected 3878 tonne

Biogas yield 380 m3/tonne of carcass waste

Biogas yield 82 m3/tonne of manure

Biogas yield 265 m3/tonne of food waste

Total biogas yield 14,293,877 m3

Electricity generation 2 kWh/m3

Heat generation 8 MJ/m3 biogas

Total electricity generation 28,587,754 kWh

Total heat generation 110,062,854 MJ

Average cost of electricity 29 c/kWh

Average heat cost 3 c/ MJ

Total income from electricity $8,176,097.72  Total income from heat $3,301,885.62  Number of operating days 335 per year

Operational Hours 24 per day

Capacity of the electricity generator 3556 kWh

Capital cost of plant $7,000.00 per kWh

Total capital cost $ 24,889,835.79  Operation cost $0.02 per kWh

Total operation cost $571,755.09 year

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Total yearly revenue $10,906,228.25 a year (with heat capture facilities)

Total yearly revenue $7,604,342.63 a year (without heat capture facilities)

3.2. Regulatory feasibility of AD in SA

3.2.1. Energy security, climate change and renewable energy policy

The availability and price can be interrupted by different factors including global climate change, regional conflicts (wars), and sudden changes in the supply-demand balance, thus, energy security is one of the biggest concerns for every country. Lack of energy security is thus linked to the negative economic and social impacts of either physical unavailability of energy, or prices that are not competitive or are overly volatile (IEA, 2014). Currently Australia has 60 days stock holding capacity which is lower than the IEA’s recommended days of 90 days (IEA, 2014). Therefore, energy generations from decentralized and locally sourced systems are important for Australia.

In regards to combating climate change, South Australia has adapted the Climate Change Adaptation Framework (SA-Govt., 2012) which has a 30 years plan for south Australia to reduce GHG emissions, efficient use of resources and sustainable energy generation from alternative energy sources. In addition, South Australia's climate change legislation sets three targets (SA-Govt., 2007):

• reduce greenhouse gas emissions within the state by at least 60% to an amount that is equal to or less than 40% of 1990 levels by 31 December 2050 as part of a national and international response to climate change;

• increase the proportion of renewable electricity generated so it comprises at least 20% of electricity generated in the state by 31 December 2014; and

• increase the proportion of renewable electricity consumed so that it comprises at least 20% of electricity consumed in the state by 31 December 2014.

3.2.2. Waste management policy

Waste management policies and strategies are important to promote certain technologies, for instance, bans of organic waste to landfill, the diversion of waste from landfills and the promotion of organic waste recycling and treatment using composting or anaerobic digestion in many European countries. The ‘zero waste’ target, which aims to divert waste from landfill, also increases recycling and composting. AD promotes zero waste activities by diverting organic waste from landfills and produces renewable energy (Zaman, 2015). Mandatory separate collection systems, landfill tax and pay as you throw (PAYT) etc. systems also have influence in the local waste management systems. Figure 3 shows the key waste management policies that influence AD in different countries.

 Figure 3: Key waste management policies that influence AD

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3.3. Key challenges and opportunities for AD in SA

Potential challenges of implementing anaerobic digestion in South Australia are to ensure consistent supply of feedstock and to maintain a homogeneous feedstock quality. It is important to have a proper organic waste recycling system in place to implement AD. Separate organic recycling bins are mandatory with a higher percentage of recycling or sorting efficiency and a least proportion of contamination. In the approximate estimation only capital cost and operation cost of the AD plant are considered, therefore, the payback time is very short. However, the overall payback time will be higher if the feedstock cost, collection and transportation cost, manpower cost and other permit cost are considered with the operation and maintenance costs. Government incentives, tipping fees and other economic incentive can significantly reduce the payback time and make AD more profitable source of renewable energy.

Small scale AD plants (Scenario 1) are not eligible for Renewable Energy Target (RET) grants in Australia, therefore, the large scale AD plants (in Scenarios 2 and 3 ) are more viable for South Australia as a waste-to-energy project. In addition, AD should not be treated as only a renewable energy technology, instead it has the potential to manages organic waste and produce bio-fertilizer which also has market value. Therefore, AD should also attract waste management incentives too for instance tipping fees or landfill tax avoidance incentives.

4. Conclusion

There is a lack of investment in the renewable energy sector particularly in waste-to-energy using AD technology despite exhibiting various sustainability potentials. Both small scale and large scale AD digestion should be encourage through policy and economic incentives so that the technology can be applied in both centralized and decentralized waste management and renewable energy generation. National and regional climate change is vital for AD as it reduces GHG emissions to the atmosphere and thus climate change incentives are important for implementing and promoting AD in any region. Active community involvement is essential as it requires a high level of organic waste sorting and recycling efficiency.

 

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Unmaking  Waste  2015  Conference  Proceedings  22  –  24May  2015  Adelaide,  South  Australia  

Current State of Scrap Utilization by Thai SMEs

Singh Intrachooto

Kasetsart University, Thailand

Area of research: Innovation process, Management of technological innovation, Environmentally responsible design and technologies, Alternative materials

The circular economy has become a top policy of countries around the world. In order to achieve a circular economy, wasteful use of resources must be reduced and waste products from manufacturing must be re-introduced into production systems. It is, however, impossible to totally avoid scraps from any production of goods. This paper describes an investigation of current practices of 108 small-and-medium-sized manufacturers (SMEs) regarding their use of solid wastes or scraps. Of particular interest are the scraps generated by SMEs because they comprise 98.5% of all manufacturers in Thailand. Despite being concerned about the growing volume of scraps from their production lines, this study collected data from both factory visits and from manufacturer surveys and found that waste reclamation policies among SMEs are rare. Most factory owners resort to selling off-cuts to formal and informal recyclers as well as dumping scraps in the city’s bins. The use of “design” has not been considered as a recirculation strategy for manufacturers. Since failures in scrap reclamation schemes for product designs also hinge on market prospects and opportunities perceived by manufacturers, market strategies in the green economy must be devised. Only then can Thailand achieve circular material flow in its industrial sector.

Keywords: Upcycle, Reuse, 3Rs, Solid Wastes, Circular Economy, Eco-Design, Waste-to-Wealth, SMEs

 

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Overview

All manufacturing processes produce leftovers. It is not possible to completely avoid scraps from the production of goods due to technical, materials and manufacturing constraints (Pacelli et.al. 2015, Intrachooto 2014). The goal to achieve a circular economy1 demands recirculation of materials into production systems. This paper describes an investigation of current situations among manufacturers regarding their solid wastes or scraps. How much thought or concern is given by the manufacturers regarding their off-cuts, remnants, scraps or dead stock? Rightly so, manufacturers are unwilling to call these underutilized materials “wastes,” and try collecting, categorizing and storing them in large warehouses. Some off-cuts have been stored for nearly 30 years, hoping that one day these remnants would be sent back into production. Rarely does that happen because most scraps get stored floor to ceiling without a designated access. Retrieving these materials for further use becomes tedious and impractical. Manufacturers recognize that wastes should be minimized and that scrap materials are valuable. Yet, off-cuts continue piling up along the production lines. When consider cradle-to-gate, some materials, such as wood off-cuts from the process of making a dining chair can be as high as 40% and stone scraps from the production of stone cladding can be as high as 50% (Intrachooto 2014). In order to gauge the country’s closed-loop economy aptitudes, this investigation aims at identifying scrap utilization potentials among small-to-medium enterprises (SMEs)2 in Thailand since 98.5% of all manufacturers in the country are SMEs (OSMEP 2014).

Methodology

Thailand’s National Science and Technology Development Agency (NSTDA), Ministry of Science, has been carrying out a “Waste to Wealth” project since 2009. The project aims at supporting Thai SMEs in achieving closed-loop production—reducing wastes that would otherwise go to landfills or incinerators. In other words, it aims to help local manufacturers reclaim their scraps and turn them into high value-added products or new materials, i.e. upcycling3. Teams of consultants were enlisted to diagnose problems, to explore ‘value-creation’ possibilities from scraps and to provide technical and design support to participating manufacturers. The ‘Waste-to-Wealth’ project’s aims include: (1) to create awareness about environmental problems from solid wastes; (2) to exchange design solutions and strategies; and (3) to disseminate knowledge about scraps categorization, reclamation techniques as well as production processes, among small-medium size enterprises (SMEs).

                                                                                                                                                                             1 Circular economy aims to avoid impact on the environment by re-circulating materials within the production systems without entering the biosphere to sustain the industrial economy. 2 Small and Medium Enterprises (SMEs) in Thailand generally refers to a manufacturer with an annual sale below USD 7 millions and number of employees less than 200. 3 Upcylcing refers to a reclamation and development of scraps or wastes with the intention to create new products of improved quality, environmental performance and commercial values.

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Figure 1: Upcycled product exhibition at Thailand International Furniture Fair 2013 and 2014

This study collected data from 2 groups of SMEs. Group 1: during 2009-2014, a total of 65 manufacturers have been visited (see Table 1). All of the manufacturers were visited at their own requests through the NSTDA office. Most of the requests came after the annual Wealth-to-Wealth exhibitions at Thailand International Furniture Fairs (host by the Ministry of Commerce) that showcase products made from industrial off-cuts (see Figure 1). The inspection process includes company presentations, factory walk-throughs, scrap collection along with wrap-up discussions and in-depth interviews. Each factory visit lasts approximately 3-4 hours. To ensure a sustainable upcycling activity, company policy on scrap reclamation is vital. The decision to join W2W project had to be approved by the top management of the company. Group 2: in addition to factory visits, a total of 148 surveys were distributed in 2012-2014, of which 43 surveys were completed in full and used for this study (see Table 2). The other 105 surveys were incomplete since most manufacturers were unable or unwilling to provide necessary information in full detail such as volumes of wastes from production or waste minimization methods. These incomplete surveys, however, remained valuable sources of data for rechecking specific aptitudes. A total of 9 survey questions, which aim at understanding the general practices of scrap utilization among Thai SMEs, are (1) number of designers and staffs; (2) types of products; (3) available tools and equipment; (4) types and volumes of scraps; (5) sizes and shapes of scraps; (6) disposal methods; (7) scrap avoidance methods; (8) barriers to scrap reclamation; and (9) scrap reclamation policies. This combined data-gathering method (factory visits and surveys) is vital to gaining a deeper understanding of the current perceptions and conditions of most Thai manufacturers.

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Table 1: Composition of Factory Visits (SMEs Group 1)

Industry Number of Manufacturer Percentage (%)

Wood 27 41.54

Textiles and leather 9 13.84

Construction / Interiors 1 1.50

Metal (steel, zinc, aluminum) 12 18.46

Glass 4 6.15

Plastics 5 7.69

Others (sport, jewelry, food) 7 10.77

Total 65 100

Table 2: Composition of Manufacturer surveyed (SMEs Group 2)

Industry Number of Manufacturer Percentage (%)

Wood 7 16.27

Textiles and leather 23 53.49

Construction 4 9.30

Metal (steel, aluminum) 3 6.98

Glass 1 2.33

Plastics / polymer 2 4.65

Others (food, house ware) 3 6.98

Total 43 100

Table 3: Summary of Data Source

SME Group Number of Manufacturer Percentage (%)

Factory visited (Group 1) 65 60.19

Manufacturer surveyed (Group 2) 43 39.81

Total 108 100

Findings

Our 65 factory visits and survey of 43 manufacturers show that most manufacturers are concerned about their growing scraps but mildly reckon about environmental problems. Slightly over half (50.77%) of visited factories have joined the “Waste to Wealth” project to combat their waste problems (see Table 4). Nearly half (46.51%) of manufacturers in the survey have policies or take actions to resolve their waste problems (see Table 5). The combined data from both groups show that approximately half of

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manufacturers in Thailand have institutionalized waste management policies (see Table 6). While the data is encouraging, it seems to go against our 5-year observation in conducting upcycling activities in Thailand. We have observed that few SMEs give tolerable attention to their waste disposal practice. A large fraction of factories that joined the W2W projects also have just developed waste management policies upon their participation in the project. Upon a closer examination of all 148 surveys, merely 13.5% (20 out of 148 surveyed) have developed policies or takes actions to mitigate waste problems. An alarmingly low number of manufacturers actually reclaim and reuse their own scraps. When being viewed internationally, the recycling rate in the Thai industry is still among the lowest; the overall recycling rates in Saudi Arabia range from 10-15% depending on the industries while that of Japan range from 80-90% (Euromonitor 2013 and 2014).

Table 4: Factories joining Waste-to-Wealth (W2W) Project (Group 1)

Factory visited Number of Manufacturer Percentage (%)

Join W2W* 33 50.77

Not Joining 32 49.23

Total 65 100

* Factories that joined W2W projects are those that have waste management policies Table 5: Institutionalized Waste Recirculation Policy (Group 2)

Waste Reclamation Policy Number of Manufacturer Percentage (%)

Have Policy 20 46.51

No Policy 23 53.49

Total 43 100

Table 6: Waste Management Policy among SMEs (Combined Group 1 & 2)

Waste management policy Number of Manufacturer Percentage (%)

YES 53 49.07

NO 55 50.93

Total 108 100

All manufacturers are aware of growing volume of discards and are eager to minimize waste during their production, largely with the intention to lower their production cost, therefore achieving a higher profit margin. Keys to waste minimization lie in the alteration of tools and equipment, production processes, raw materials management, as well as staff training. This generally requires capital investments such as purchasing new equipment and production control systems. Most manufacturers hesitated. Despite manufacturers’ best efforts, scraps continue to increase in volume—occupying

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large warehouse spaces and requiring staffs to constantly sort out and sell off scraps at very low returns.

Table 7: Popular scrap management methods (from the 43 surveys & 65 visits)

Method Number of Manufacturer Percentage (%)

Selling scraps to recyclers 56 51.85

Incinerate for heat 26 24.07

Recycle 8 7.41

Reuse as fillers 6 5.56

Reclaim for new products (design) 7 6.48

Others (donation, city bins) 3 2.78

Total 108 100

Some “feel-good” scrap reclamation techniques deployed by manufacturers today are labeling scraps and storing them in a designated area, or developing new items from scraps simply for in-house usage. However, 51.85% of manufacturers sell off scraps cheaply to recyclers instead of attempting to reclaim them for product development (see Table 7). In spite of the growing volume of off-cuts, most manufacturers remain unwilling to risk making upfront investments in tools or in hiring designers or in prototyping of new products from scraps. Designers are mostly perceived as nuisance. Prototypes are often seen as an ad-hoc tasks and a time hog and therefore would be produced during “free-time”. Currently, popular methods employed by Thai SMEs to manage scraps are:

1- Sell scraps to recyclers cheaply. Informal recyclers pick up scraps at the factory gates. No effort by the manufacturers is required to transport scraps elsewhere. This is a matter of convenience.

2- Incinerate scraps for energy/heat (particularly for wood off-cuts). Most wood furniture factories need to kiln dry their wood supplies. Wood scraps, sometimes large sizes, become heat source.

3- Remix with new materials (Recycle) or reuse scraps as fillers is most practiced among the plastic/polymer manufacturers.

4- Reclaim remnants for production of existing product lines by cutting small components from large-sized scraps to be used for existing products.

Despite the availability of scrap materials within their premises, rarely do manufacturers turn scraps into new commercial products. Only 6.48% of companies employ “design” as a tool for waste reclamation (Table 7). Out of 43 manufacturers surveyed (Group 2), 29 of them utilize in-house designers to work with their own factory wastes. This encouraging data seems to suggest some popularity for “design” as a tool for scrap reclamation. However, a closer re-examination of all 148 surveys, only 20% (29 out of 148 surveyed) sought out ideas from designers to reclaim their wastes for new products. The rest (119 out of 148) did not consider “design” as a creative waste management tactic. This suggests that “design” has not been part of a problem-solving

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tool for wastes mitigation among Thai SMEs even though there are numerous successful upcycling enterprises such as Terracycle (USA) or Osisu (Thailand).

Table 8: Barriers to Scrap Reclamation

Ranking Barriers Number of Manufacturer Percentage (%)

1 Unwieldy sizes and shapes of scraps 58 53.70

2 Lack of manpower and time 22 20.37

3 Unforeseen market prospect 16 14.81

4 Lack of proper tools and equipment 7 6.48

5 Lack of storage space for scraps 5 4.63

Total 108 100

Even though manufacturers in this study have provided lists of barriers to upcycling, the top barrier from each of them were brought out to pinpoint the greatest obstacles. By far the biggest barrier to reclaiming scraps for product design is that the scraps are too difficult to deal with since the sizes and shapes vary greatly (see Table 8). Factory owners reasoned that such unwieldy scraps would demand great efforts both in terms of manpower and time. Factories in this study operate as Original Equipment Manufacturer (OEM) who supply products or parts to other brands both local and abroad. They are not familiar with developing their own products. Without a ready market, they hesitate to take risks for fear of poor investment since all expenses are viewed as direct cost to a product. It must be noted that most Thai SMEs do not allocate a budget for research and development (R&D). Storing and taking inventory of their scraps without a committed market seems illogical and hence being disregarded quickly.

Designers are trained with a responsibility to improve quality of life and to be committed to sustainable uses of resources through their creative outputs (Bramston and Maycroft 2014). Most of the scraps generated from manufacturing facilities are also the result of design decisions. Integrating design into scrap reclamation seems common sense but rarely practiced among Thai SMEs. The technical hurdles such as the lack of manpower or storage space and having unwieldy scraps could be overcome with proper training and design assistance while the market prospect could be resolved through appropriate environmental policies and marketing strategies at the state levels because these untamed barriers prevent widespread practice of scrap reclamation among SMEs in Thailand.

Conclusion

This study is a necessary groundwork to the development of sustainable scrap upcycling strategies. Despite the steady growth of upcycled products in the market (Bramston and Maycroft 2014) and confirmations by marketing gurus that upcycled products can enhance brand image of a company (Munro 2012), manufacturers, by and large, do not reclaim their scraps for new product development and manufacturing. The fear of customers’ rejection and lack of market outlets for upcycled products are

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major obstacles. Scrap management methods, however, varied greatly among product categories. Materials such as textile, leather and wood scraps have been upcycled more often than concrete and masonry wastes, for example. This means that further studies should be product or material specific (Burke et al. 1978; DeBell and Dardis 1979). Based on the assessment of the survey and factory visits, potentials for circular production among Thai SMEs is grim due to the fact that only a fraction of manufacturers have institutionalized scrap-reclamation policies or employ new tactics such as design to re-circulate scraps into the production of new products. In response to the growing global eco market, an environmental labeling to endorse upcycled products is necessary for widespread commercialization through green procurement. In this study, we also attempted to find a correlation between the number of designers in a factory and the volume of waste or the reclamation rate. Although we could not identify such a relationship, this study illustrates the state of mind among Thai SMEs and quantifies how few have considered using “design” as a tool to manage scraps. Government policies and subsidies on upcycling may need to be instituted similar to that of the energy sectors; and it should be done in parallel with factory training in scrap categorization and design collaboration to ensure a sustainable upcycling activity. This study shows that most factories do not yet have the design capacity. Without such a concerted effort, Thailand will continue to be among the top 10 list of countries that put most trash into the ocean (Parker 2015).

References

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Burke, M., Conn, W.D. and Lutz, R.J. (1978) “Using psychological variables to investigate product disposition behaviors,” Proceedings of Educators conference, American Marketing Association: 321-326.

DeBell, M. and Dardis, R. (1979) “Extending product life: Technology isn’t the only issue,” Advances in Consumer Research, vol.: 381-385.

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Euromonitor International (August 2013) “Recycling of non-metal waste and scrap in Japan: ISIC372,” http://www.euromonitor.com/recycling-of-non-metal-waste-and-scrap-in-japan-isic-372/report (accessed on 20 February 2015)

Intrachooto, S. (2014) Upcycling, National Science and Technology Development Agency: Bangkok.

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Office of Small and Medium Enterprises Promotion (2014) “OSMEP’s 2014 Prediction,” http://www.sme.go.th/Lists/EditorInput/DispF.aspx?List=15dca7fb-bf2e-464e-97e5-440321040570&ID=2235 (accessed on 12 November 2014)

Pacelli, F.; Ostuzzi, F. and Levi, M. (2015) “Reducing and reusing industrial scraps: a proposaed method for industrial designers,” Journal of Cleaner Production, No.86: 78-87.

Parker, L. (2015) “New study shows plastic in ocean is on the rise,” National Geographic: http://news.nationalgeographic.com/news/2015/02/150212-ocean-debris-plastic-garbage-patches-science/ (accessed on 12 February 2015)

Acknowledgement

Much appreciation to Roongtip Luilao, a colleague from the Faculty of Agriculture at Kasetsart Unversity, for coordinating with multiple assistants in data collection and to Jaksin Noiraipoom, doctoral researcher in the Faculty of Architecture for organizing the data and turn it into a coherent format as well as to Dr. Sopapun Sangsupata and Denise Domergue for their assistance in reviewing this paper