Waste Disposal Methods: Perspectives for Africa

Waste disposal methods vary from city to city, state to state and region to region. It equally depends on the kind and type of waste generated. In determining the disposal method that a city or nation should adopt, some factors like type, kind, quantity, frequency, and forms of waste need to be considered.

For the purpose of this article, we will look at the three common waste disposal methods and the kind of waste they accept.

Open Dumping/Burning

This is the crudest means of disposing of waste and it is mostly practiced in rural areas, semi-urban settlements, and undeveloped urban areas. For open dumping or open burning, every type and form of waste (including household waste, hazardous wastes, tires, batteries, chemicals) is dumped in an open area within a community or outside different homes in a community and same being set on fire after a number of days or when the waste generator or community feels it should be burnt.

There is no gainsaying that the negative health and environmental impact of such practice are huge only if the propagators know better.

Controlled Dumping

This is apparent in most States in Nigeria, if not all and some cities in Africa like Mozambique, Ghana, Kenya, Cameroon, to mention but a few. It is a method of disposing of all kinds of waste in a designated area of land by waste collectors and it is usually controlled by the State or City Government.

Opening burning of trash is a common practice across Africa

Controlled dumps are commonly found in urban areas and because they are managed by the government, some dumps do have certain features of a landfill like tenure of usage, basic record keeping, waste covering, etc. Many cities in Nigeria confuse the practice of controlled dumping as landfilling but this not so because a landfill involves engineering design, planning, and operation.

Sanitary Landfill

A sanitary landfill is arguably the most desired waste management option in reducing or eliminating public health hazards and environmental pollution. The landfill is the final disposal site for all forms and types of waste after the recyclable materials must have been separated for other usages and other biodegradables have been extracted from the waste for use as compost, heat, or energy; or after incineration. These extractions can be done at household level or Material Recovery Facilities (MRFs) operated by the government or private individuals.

As desirable as a landfill is, so many factors need to be put into consideration in its siting and operation plus it requires a huge investment in construction and operation. Some of these factors include but not limited to distance from the residential area, proximity to water bodies, water-table level of the area the landfill is to be sited, earth material availability, and access road.

Note: The original version of the article was published on Waste Watch Africa website at this link.

Environmental Costs of Glitter

While there are no clear estimates of the amount of glitter sold each year, its distinctive ability to disperse makes it a disproportionate contributor to environmental problems. Glitter particles are easily transferred through the air or by touch, clinging to skin and clothes. Its ability to spread is so notorious that there are companies that will ‘ship your enemies glitter’ that is guaranteed to infest every corner of their home. Glitter has even been used in forensic science to show that a suspect has been at a crime scene. This characteristic, and the plastics it contains, makes it something of an environmental peril. It causes problems for paper recyclers: glitter on cards and gift wrap can foul up the reprocessing equipment, and even contaminate the recycled pulp.

A Growing Problem

Most glitter is cut from multi-layered sheets, combining plastic, colouring, and a reflective material such as aluminium, titanium dioxide, iron oxide, or bismuth oxychloride. It therefore contributes to the more than 12.2 millions of tonnes of plastic that enters the ocean each year – not least when people wear it and then wash it off. Worse still, glitter is a microplastic, and there are growing concerns about these tiny pieces of material entering the marine food chain and harming marine life.

The polyethylene terephthalate (PET) that is often used in glitter is thought to leach out endocrine-disrupting chemicals, which, when eaten by marine creatures, can adversely affect development, reproduction, neurology and the immune system. PET can also attract and absorb persistent organic pollutants and pathogens, adding an extra layer of contamination.

When molluscs, sea snails, marine worms, and plankton eat pathogen or pollutant-carrying particles of glitter, they can concentrate the toxins; and this concentration effect can continue as they in turn are eaten by creatures further up the food chain, all the way to our dinner plates.

Time for Action

As consciousness of the environmental damage caused by glitter increases, some are taking drastic action. In November 2017 Tops Days Nurseries a group of English nurseries banned glitter for its contribution to the plastic pollution problem. But our attraction to sparkly things is literally age old, and won’t be given up easily.

Research has demonstrated that humans are attracted to shiny, sparkly things, which is thought to stem from our evolutionary instinct to seek out shimmering bodies of water. As early as 30,000 years ago, mica flakes were used to give cave paintings a glittering appearance, while the ancient Egyptians produced glittering cosmetics from the iridescent shells of beetles as well as finely ground green malachite crystal. Green glitter fans might well wonder if environmentally friendly glitter is available, and there is in fact a growing market of products that claim eco credentials.

Shining examples

British scientist Stephen Cotton helped develop ‘eco-glitter’ made from eucalyptus tree extract and aluminium. This appears to be sold by companies like EcoStarDust, whose short list of materials included only ‘non-GMO eucalyptus trees’. Their website explains if you leave your glitter in a warm, moist and oxygenated environment then it will begin to biodegrade, with the rate depending on the mixture of these factors. However, it is not clear that a product that may release aluminium into the environment deserves a green vote of confidence.

Wild Glitter another company also explains their sparkles are made from natural plant based materials but they don’t a lot of detail about how they’re made and what happens to them once used. Other brands, such as EcoGlitterFunBioGlitz and Festival Face, offer biodegradable glitter made from a certified compostable film.

Awareness about the environmental damage caused by glitter is steadily increasing

However, it is difficult for a consumer to be sure, without a good deal of research, that such products will break down quickly and harmlessly in the natural environment – or whether they require specific industrial composting processes.

Other manufacturers are turning instead to natural ingredients that add shine and sparkle; environmentally conscious cosmetic brand LUSH uses ground nut shells and aduki beans in its products. They also started using inert mica to create sparkly things, like the cave painters from millennia ago. Unfortunately, this meant trading an environmental problem for a human rights one: difficulties with the natural mica supply chain made it impossible to guarantee that the process was free from child labour, prompting a forthcoming switch to synthetic mica.

Parting Shot

There’s a lot of grey area when it comes to choosing greener glitter, and little objective evidence available regarding the environmental impacts of the different alternatives. I’ve seen little sign, for example, of a glitter product that claims to be compatible with paper and card recycling processes. But it’s crystal clear that, with enormous variety of options available, it should be possible do without glitter made from PET – even at Christmas.

 

Note: The article has been republished with the permission of our collaborative partner Isonomia. The original version of the article can be found at this link

Circular Economy: Past, Present and Future

For a society accustomed to the achievements of a linear economy, the transition to a circular economic system is a hard task even to contemplate. Although the changes needed may seem daunting, it is important to remember that we have already come a long way. However, the history of the waste hierarchy has taught that political perseverance and unity of approach are essential to achieving long term visions in supply chain management.

Looking back, it is helpful to view the significance of the Lansink’s Ladder in the light of the sustainability gains it has already instigated. From the outset, the Ladder encountered criticism, in part because the intuitive preference order it expresses is not (and has never been put forward as) scientifically rigorous. Opposition came from those who feared the hierarchy would impede economic growth and clash with an increasingly consumerist society. The business community expressed concerns about regulatory burdens and the cost of implementing change.

Circular-Economy

However, such criticism was not able to shake political support, either in Holland where the Ladder was adopted in the Dutch Environmental Protection Act of 1979, or subsequently across Europe, as the Waste Hierarchy was transposed into national legislation as a result of the revised Waste Framework Directive.

Prevention, reuse and recycling have become widely used words as awareness has increased that our industrial societies will eventually suffer a shortage of raw materials and energy. So, should we see the waste hierarchy as laying the first slabs of the long road to a circular economy? Or is the circular economy a radical new departure?

Positive and negative thinking

There have been two major transitionary periods in waste management: public health was the primary driver for the first, from roughly 1900 to 1960, in which waste removal was formalised as a means to avoid disease. The second gained momentum in the 1980s, when prevention, reuse and recovery came on the agenda. However, consolidation of the second transition has in turn revealed new drivers for a third. Although analysing drivers is always tricky – requiring a thorough study of causes and effects – a general indication is helpful for further discussion. Positive (+) and negative (-) drivers for a third transition may be:

(+) The development of material supply chain management through the combination of waste hierarchy thinking with cradle to cradle eco design;

(+) The need for sustainable energy solutions;

(+) Scarcity of raw materials necessary for technological innovation; and

(+) Progressive development of circular economy models, with increasing awareness of social, financial and economic barriers.

(-) Growth of the global economy, especially in China and India, and later in Africa;

(-) Continued growth in global travel;

(-) Rising energy demand, exceeding what can be produced from renewable energy sources and threatening further global warming;

(-) Biodiversity loss, causing a further ecological impoverishment; and

(-) Conservation of the principle of ownership, which hinders the development of the so-called ‘lease society’. 

A clear steer

As the direction, scale and weight of these drivers are difficult to assess, it’s necessary to steer developments at all levels to a sustainable solution. The second transition taught that governmental control appears indispensable, and that regulation stimulates innovation so long as adequate space is left for industry and producers to develop their own means of satisfying their legislated responsibilities.

The European Waste Framework Directive has been one such stimulatory piece of legislation. Unfortunately, the EC has decided to withdraw its Circular Economy package, which would otherwise now be on track to deliver the additional innovation needed to achieve its goals – including higher recycling targets. Messrs. Juncker and Timmermans must now either bring forward the more ambitious legislation they have hinted at, or explain why they have abandoned the serious proposals of their predecessors.

Perhaps the major differences between Member States and other countries may require a preliminary two-speed policy, but any differences in timetable between Western Europe and other countries should not stand in the way of innovation, and differences of opinion between the European Parliament and the Commission must be removed for Europe to remain credible.

Governmental control requires clear rules and definitions, and for legislative terminology to be commensurate with policy objectives. One failing in this area is the use of the generic term ‘recovery’ to cover product reuse, recycling and incineration with energy recovery, which confuses the hierarchy’s preference order. The granting of R1 status to waste incineration plants, although understandable in terms of energy diversification, turns waste processors into energy producers benefiting from full ovens. Feeding these plants reduces the scope for recycling (e.g. plastics) and increases COemissions. When relatively inefficient incinerators still appear to qualify for R1 status, it offers confusing policy signals for governments, investors and waste services providers alike.

The key role for government also is to set clear targets and create the space for producers and consumers to generate workable solutions. The waste hierarchy’s preference order is best served by transparent minimum standards, grouped around product reuse, material recycling or disposal by combustion. For designated product or material categories, multiple minimum standards are possible following preparation of the initial waste streams, which can be tightened as technological developments allow.

Where the rubber meets the road

As waste markets increase in scale, are liberalised, and come under international regulation, individual governmental control is diminished. These factors are currently playing out in the erratic prices of secondary commodities and the development of excess incinerator capacity in some nations that has brought about a rise in RDF exports from the UK and Italy. Governments, however, may make a virtue of the necessity of avoiding the minutiae: ecological policy is by definition long-term and requires a stable line; day to day control is an impossible and undesirable task.

The road to the third transition – towards a circular economy – requires a new mind-set from government that acknowledges and empowers individuals. Not only must we approach the issue from the bottom-up, but also from the side and above. Consumer behaviour must be steered by both ‘soft’ and ‘hard’ controls: through information and communication, because of the importance of psychological factors; but also through financial instruments, because both consumers and industry are clearly responsive to such stimuli.

Where we see opposition to deposit return schemes, it comes not from consumers but from industry, which fears the administrative and logistical burden. The business community must be convinced of the economic opportunities of innovation. Material supply chain management is a challenge for designers and producers, who nevertheless appreciate the benefits of product lifetime extensions and reuse. When attention to environmental risks seems to lapse – for example due to financial pressures or market failures – then politics must intervene.

Government and industry should therefore get a better grip on the under-developed positive drivers of the third transition, such as eco design, secondary materials policy, sustainable energy policy, and research and development in the areas of bio, info, and nanotechnologies. 

Third time’s the charm

Good supply chain management stands or falls with the way in which producers and consumers contribute to the policies supported by government and society. In order that producers and consumers make good on this responsibility, government must first support their environmental awareness.

The interpretation of municipal duty of care determines options for waste collection, disposal and processing. Also essential is the way in which producer responsibility takes shape, and the government must provide a clear separation of private and public duties. Businesses may be liable for the negative aspects of unbridled growth and irresponsible actions. It is also important for optimal interaction with the European legislators: a worthy entry in Brussels is valuable because of the international aspects of the third transition. Finally, supply chain management involves the use of various policy tools, including:

  • Rewarding good behaviour
  • Sharpening minimum standards
  • Development and certification of CO2 tools
  • Formulation and implementation of end-of-waste criteria
  • Remediation of waste incineration with low energy efficiency
  • Restoration or maintenance of a fair landfill tax
  • Application of the combustion load set at zero

‘Seeing is believing’ is the motto of followers of the Apostle Thomas, who is chiefly remembered for his propensity for doubt. The call for visible examples is heard ever louder as more questions are raised around the feasibility of product renewal and the possibilities of a circular economy.

Ultimately, the third transition is inevitable as we face a future of scarcity of raw materials and energy. However, while the direction is clear, the tools to be employed and the speed of change remain uncertain. Disasters are unnecessary to allow the realisation of vital changes; huge leaps forward are possible so long as government – both national and international – and society rigorously follow the preference order of the waste hierarchy. Climbing Lansink’s Ladder remains vital to attaining a perspective from which we might judge the ways in which to make a circle of our linear economy.

Note: The article is being republished with the permission of our collaborative partner Isonomia. The original article can be found at this link.

Waste Management in Peshawar

Peshawar is among the biggest cities in Pakistan with estimated population of 4 million inhabitants. Like most of the cities in Pakistan, solid waste management is a big challenge in Peshawar as the city generate 600-700 tons of municipal waste every day. with per capita generation of about 0.3 to 0.4 kg per day. Major part of the Peshawar population belongs to low and middle income area and based upon this fact, waste generation rate per capita varies in different parts of the city.

Municipal solid waste collection and disposal services in the city are poor as approximately 60 per cent of the solid wastes remain at collection points, or in streets, where it emits a host of pollutants into the air, making it unacceptable for breathing. A significant fraction of the waste is dumped in an old kiln depression around the southern side of the city where scavengers, mainly comprising young children, manually sort out recyclable materials such as iron, paper, plastics, old clothes etc.

Peshawar has 4 towns and 84 union councils (UCs). Solid waste management is one of their functions. Now city government has planned to build a Refuse Derived Fuel (RDF), Composting Plant and possibly a Waste to Energy Power Plant which would be a land mark of Peshawar city administration.

The UCs are responsible for door to door collection of domestic waste and a common shifting practice with the help of hand carts to a central pick-up points in the jurisdiction of each UC. Town Council is responsible for collection and transporting the mixed solid waste to the specified dumps which ends up at unspecified depressions, agricultural land and roadside dumps.

Open dumping of municipal wastes is widely practiced in Peshawar

Presently, there are two sites namely Hazar Khwani and Lundi Akhune Ahmed which are being used for the purpose of open dumping. Scavenging is a major activity of thousands of people in the city. An alarming and dangerous practice is the burning of the solid waste in open dumps by scavengers to obtain recyclables like glass and metals.

Almost 50 percent of recyclables are scavenged at transfer stations from the waste reaching at such points. The recyclable ratio that remains in the house varies and cannot be recovered by the authorities unless it is bought directly from the households. Only the part of recyclables reaching a certain bin or secondary transfer station can be exploited.

In some areas of city where waste is transported by private companies from transfer points to the disposal site out study found that scavengers could only get about 35% of the recyclables from the waste at transfer station. Considering the above fact, it can be inferred that in case municipality introduces efficient waste transfer system in the city, the amount of recyclables reaching the disposal facility may increase by 30% of the current amount. In case house-to-house collection is introduced the municipality will be able to take hold of 90% of the recyclables in the waste stream being generated from a household.

Waste Management Outlook for India

Waste management crisis in India should be approached holistically; while planning for long term solutions, focus on addressing the immediate problems should be maintained. National and local governments should work with their partners to promote source separation, achieve higher percentages of recycling and produce high quality compost from organics. While this is being achieved and recycling is increased, provisions should be made to handle the non-recyclable wastes that are being generated and will continue to be generated in the future.

Recycling, composting and waste-to-energy are all integral parts of the waste disposal solution and they are complementary to each other; none of them can solve India’s waste crisis alone. Any technology should be considered as a means to address public priorities, but not as an end goal in itself. Finally, discussion on waste management should consider what technology can be used, to what extent in solving the bigger problem and within what timeframe.

Experts believe India will have more than nine waste-to-energy projects in different cities across India in the next three years, which will help alleviate the situation to a great extent. However, since waste-to-energy projects are designed to replace landfills, they also tend to displace informal settlements on the landfills. Here, governments should welcome discussions with local communities and harbor the informal recycling community by integrating it into the overall waste management system to make sure they do not lose their rights for the rest of the city’s residents.

This is important from a utilitarian perspective too, because in case of emergency situations like those in Bengaluru, Kerala, and elsewhere, the informal recycling community might be the only existing tool to mitigate damage due to improper waste management as opposed to infrastructure projects which take more than one year for completion and public awareness programs which take decades to show significant results.

Involvement of informal recycling community is vital for the success of any SWM program in India

Indian policy makers and municipal officials should utilize this opportunity, created by improper waste management examples across India, to make adjustments to the existing MSW Rules 2000, and design a concrete national policy based on public needs and backed by science. If this chance passes without a strong national framework to improve waste management, the conditions in today’s New Delhi, Bengaluru, Thiruvananthapuram, Kolkata, Mumbai, Chennai, Coimbatore and Srinagar will arise in many more cities as various forcing factors converge. This is what will lead to a solid waste management crisis affecting large populations of urban Indians.

The Indian Judiciary proved to be the most effective platform for the public to influence government action. The majority of local and national government activity towards improving municipal solid waste management is the result of direct public action, funneled through High Courts in each state, and the Supreme Court. In a recent case (Nov 2012), a slew of PILs led the High Court of Karnataka to threaten to supersede its state capital Bengaluru’s elected municipal council, and its dissolution, if it hinders efforts to improve waste management in the city.

In another case in the state of Haryana, two senior officials in its urban development board faced prosecution in its High Court for dumping waste illegally near suburbs. India’s strong and independent judiciary is expected to play an increasing role in waste management in the future, but it cannot bring about the required change without the aid of a comprehensive national policy.

Note: Acknowledgements will be published in the full report “Observations from India’s Crisis” on wtert.org and blog.wtert.org

Progress of Waste-to-Energy in the USA

Rising rates of consumption necessitate an improved approach to resource management. Around the world, from Europe to Asia, governments have adapted their practices and policies to reflect renewability. They’ve invested in facilities that repurpose waste as source of energy, affording them a reliable and cheap source of energy.

This seems like progress, given the impracticality of older methods. Traditional sources of energy like fossil fuels are no longer a realistic option moving forward, not only for their finite nature but also within the context of the planet’s continued health. That said, the waste-to-energy sector is subject to scrutiny.

We’ll detail the reasons for this scrutiny, the waste-to-energy sector’s current status within the United States and speculations for the future. Through a concise analysis of obstacles and opportunities, we’ll provide a holistic perspective of the waste-to-energy progress, with a summation of its positive and negative attributes.

Status of Waste-to-Energy Sector

The U.S. currently employs 86 municipal waste-to-energy facilities across 25 states for the purpose of energy recovery. While several have expanded to manage additional waste, the last new facility opened in 1995. To understand this apparent lack of progress in the area of thermochemical treatment of MSW, budget represents a serious barrier.

One of the primary reasons behind the shortage of waste-to-energy facilities in the USA is their cost. The cost of construction on a new plant often exceeds $100 million, and larger plants require double or triple that figure to build. In addition to that, the economic benefits of the investment aren’t immediately noticeable.

The Palm Beach County Renewable Energy Facility is a RDF-based waste-to-energy (WTE) facility.

The U.S. also has a surplus of available land. Where smaller countries like Japan have limited space to work within, the U.S. can choose to pursue more financially viable options such as landfills. The expenses associated with a landfill are far less significant than those associated with a waste-to-energy facility.

Presently, the U.S. processes 14 percent of its trash in waste-to-energy (WTE) plants, which is still a substantial amount of refuse given today’s rate of consumption. On a larger scale, North America ranks third in the world in the waste-to-energy movement, behind the European nations and the Asia Pacific region.

Future of WTE Sector

Certain factors influence the framework of an energy policy. Government officials have to consider the projected increase in energy demand, concentrations of CO2 in the atmosphere, space-constrained or preferred land use, fuel availability and potential disruptions to the supply chain.

A waste-to-energy facility accounts for several of these factors, such as space constraints and fuel availability, but pollution remains an issue. Many argue that the incineration of trash isn’t an effective means of reducing waste or protecting the environment, and they have evidence to support this.

The waste-to-energy sector extends beyond MSW facilities, however. It also encompasses biofuel, which has seen an increase in popularity. The aviation industry has shown a growing dedication to biofuel, with United Airlines investing $30 million in the largest producer of aviation biofuel.

If the interest of United Airlines and other companies is any indication, the waste-to-energy sector will continue to expand. Though negative press and the high cost of waste-to-energy facilities may impede its progress, advances in technology promise to improve efficiency and reduce expenses.

Positives and Negatives

The waste-to-energy sector provides many benefits, allowing communities a method of repurposing their waste. It has negative aspects that are also important to note, like the potential for pollution. While the sector offers solutions, some of them come at a cost.

It’s true that resource management is essential, and adapting practices to meet high standards of renewability is critical to the planet’s health. However, it’s also necessary to recognize risk, and the waste-to-energy sector is not without its flaws. How those flaws will affect the sector moving forward is critical to consider.

The Technology Revolutionizing Commercial Waste Management

Every single one of us can do something to improve our impact on the planet, but it is a given that businesses of all sizes have a bigger footprint than families – commercial accounts for 12% of total greenhouse gas emissions. A big factor of that is waste management. From the physical process of picking up garbage, to the methane-released process of decomposition, there are numerous factors that add up to create a large carbon footprint.

Between hiring green focused waste management solutions and recycling in a diligent fashion, there are a few technologies that are helping to break down the barrier between commercial waste management and an environmentally positive working environment.

Cleaning up commercial kitchens

A key form of commercial waste is food waste. Between the home and restaurant, it is estimated by the US Department of Agriculture that 133 billion pounds of food is wasted every year. Much will end up in the landfill. How is technology helping to tackle this huge source of environmental waste? Restaurants themselves are benefiting from lower priced and higher quality commercial kitchen cooking equipment, that helps to raise standards and reduce wastage.

Culinary appliances for varied cuisines also benefit from a new process being developed at the Netherland’s Wageningen University. A major driver of food waste is rejected wholesale delivery, much of which will be disposed of in landfill. The technology being developed in Holland aims to reduce wastage by analyzing food at the source, closer to where recycling will be achievable.

Route optimization

Have you ever received a parcel from an online retailer only to find the box greatly outsizes the contents? On the face of it, this is damaging to the environment. However, many retailers use complex box sorting algorithms. The result is that the best route is chosen on balance, considering the gas needed to make the journey, the amount of stock that can be delivered and the shortest route for the driver. This is an area of intense technological innovation.

The National Waste & Recycling Association reported in 2017 on how 2018 would see further advances, particularly with the integration of artificial intelligence and augmented reality into the route-finding process.

Balancing the landfill carbon footprint

It is well established that landfills are now being used to power wind turbines, geothermal style electricity and so on. They are being improved to minimize the leachate into groundwater systems and to prevent methane escaping into the atmosphere. However, further investigation is being pushed into the possibility of using landfill as a carbon sequester.

AI-based waste management systems can help in route optimization and waste disposal

Penn State University, Lawrence Berkeley and Texas University recently joined together to secure a $2.5m grant into looking into the function of carbon, post-sequestration. This will help to shed light on the carbon footprint and create a solid foundation on which future technology can thrive.

Businesses of all sizes have an impact on the carbon footprint of the world. The various processes that go into making a business profitable and have a positive impact on their local and wider communities need to be addressed. As with many walks of life, technology is helping to bridge the gap.

Bioplastics: Making an Informed Decision

bioplasticsPlastics are regarded by some as one of the greatest human inventions and continue to benefit society in more ways than one. However these benefits come at a high environmental cost as research has shown that “over 300 million metric tons of plastics are produced in the world annually and about 50% of this volume is for disposable applications, products that are discarded within a year of their purchase”.

About 50 percent of all plastics produced worldwide are disposed of within one year of being manufactured; now that is a critically important statistic when plastics have been known to have life spans over 500 years.  Infact, this is the main reason behind massive waste accumulation of plastics in landfills, drainage systems, water bodies etc. Moreover, plastic’s destruction is evident when in 2009, it was reported that an estimated 150 million tons of fossil fuels were consumed for the production of plastics worldwide.  Given all of these facts, it is no surprise that the pervasive use of non-biodegradable plastics has provoked many environmental and health concerns, especially in developing countries where plastic is often disposed of in unauthorized dumping sites or burned uncontrollably.

One result of this broadening awareness of the global plastic waste problem and its impact on the environment is the development of bioplastics.  Bioplastics are based on biomass derived from renewable resources and are in many cases more environmentally friendly than traditional petroleum based plastics. Currently, numerous types of bioplastics are under development, the most popular being “Polylactides, Polyglycolic acids, Polyhydroxyalkanoates (PHAs), aliphatic polyesters, polysaccharides”.

Basic Concepts and Misconceptions

Overall, in the Plastics Industry Trade Association’s 2012 Bioplastics Industry Overview Guide, it is stated that bioplastics that are both bio-based and biodegradable play an important role in further advancing the plastic industry as a whole.  Incredibly essential to note, is that within the above statement, it states, the importance of bioplastics that are both bio-based and biodegradable.  This statement implys that not all bioplastics are biodegradable and/or bio-based.  In fact, according to a 2011 industry report, there are many characteristics such as degradable, biodegradable, bio-based and compostable that are used to describe bioplastics. However, not every bioplastic is comprised of all of these features.  According to the report, this remains a common misconception as the public at large still lacks a clear understanding of the various bioplastic related terms.  For instance, it is commonly thought of that the terms bio-based and biodegradable are interchangeable. However not all bio-based plastics will degrade naturally. In fact, “many bio-based products are designed to behave like traditional petroleum-based plastic, and remain structurally intact for hundreds of years”.

The American Society for Testing and Materials (ASTM) defines biodegradable plastics as a plastic in which all the organic carbon can be converted into biomass, water, carbon dioxide, and/or methane via the action of naturally occurring microorganisms such as bacteria and fungi, in timeframes consistent with the ambient conditions of the disposal method (Compostable Plastics 101). This definition implies that there is a specific timeframe for the biodegradation to take place and merely fragmenting into smaller pieces, even if microscopic, does not make a material biodegradable.  This definition is commonly confused with the term degradable which is a broader term given to polymers or plastics that simply break down by a number or means, such as physical disintegration, chemical disintegration and biodegradation by natural mechanisms. After degradation, a degradable plastic can still remain in a smaller or fragmented form unlike that of a biodegradable plastic, which needs to completely biodegrade into water, carbon dioxide and/or methane. This distinction between terms results in polymers that are degradable but not biodegradable.

Another term that is commonly found to describe bioplastics is ‘compostable’. Compostable is defined by ASTM as “a plastic that undergoes biological degradation during composting to yield carbon dioxide, water, inorganic compounds, and biomass at a rate consistent with other known compostable materials and leaves no visually distinguishable or toxic residues”. While the ASTM has specific standards for a plastic to be compostable such as biodegradation, eco-toxicity, and disintegration, the main difference between a plastic being compostable versus biodegradable is the rapid rate at which biodegradation, eco-toxicity, and disintegration occur. Therefore, in theory, all compostable plastics are biodegradable however, not all biodegradable plastics are compostable.

Finally, probably the most often confused term regarding bioplastics is the label, “bio-based”.  As defined by the US Department of Agriculture, the term “bio-based” refers to solely the raw materials of the plastic. According to the Department of Agriculture, bio-based materials that are those that are “composed in whole, or in significant part, of biological products or renewable domestic agricultural materials or forestry materials”. Since the majority, not all, of the materials have to be renewable, many bio-based plastics combine both petroleum-based materials with naturally based ones. For this reason, some researchers have suggested that a bio-based material may not technically be a sustainable product. Therefore, while the two terms are somewhat related, whether or not a product is bio-based is not an independent indicator of whether it is biodegradable.

Making an Informed Decision

This lack of understanding between the terms is a large issue that does not get much recognition.  Consumers are increasingly buying more and more bioplastics but are not fully being educated on the differences between the various different types of bioplastics on the markets. While as a whole, bioplastics may have many notable attributes making them excellent alternatives to traditional plastics, they are not considered flawless solutions. Some bioplastics encompass all of the above qualities while others may only hold one or two of these characteristics; meaning that there is a vast disparity between how environment-friendly different bioplastics might actually be.

Consumers often see the term bioplastic or a bio-based plastic and automatically assume that it will breakdown into the soil like leaves or grass once it is disposed of, when as discussed, this is often not the case. All in all, given the significant differences between the terms, it is very important for consumers to know that “bio-based,” “biodegradable” and “compostable” are individual attributes and be educated on what these characteristics actually mean. It is equally important for manufacturers to be educated on these differences and make proper labeling of their bioplastic products.

References

Biobased and degradable plastics in California. Retrieved from  this link

California Organics Recycling Council. (2011). Compostable plastics 101. Retrieved from this link

Confused by the terms biodegradable & biobased. (n.d.). Retrieved from this link

Divya, G., Archana, T., & Manzano, R. A. (2013). Polyhydroxy alkanoates – A sustainable alternative to petro-based plastics. Petroleum & Environmental Biotechnology, 4(3), 1-8. http://dx.doi.org/10.4172/2157-7463.1000143

Liu, H-Y. (2009). Bioplastics poly(hydroxyalkanoate) production during industrial wastewater treatment. Retrieved from ProQuest Digital Dissertations. (AAT 3362495)

Niaounakis, M. (2013). Biopolymers: Reuse, recycling, and disposal. Waltham, MA: William Andrew Publishing.

North, E. J., & Halden, R. U. (2013). Plastics and environmental health: the road ahead. Reviews on Environmental Health, 28(1), 1-8. doi: 10.1515/reveh-2012-0030

The Society of the Plastics Industry, Inc. (2012, April). Bioplastics Industry Overview Guide. Retrieved from this link

United States Department of Agriculture. (2006). Federal biobased products preferred procurement program. Retrieved from this link

Circular Economy: Viewpoint of Plastic

plastic-bottle

Pieces of plastic have been trying to get our attention. The first scientific reports of plastic pollution in oceans were in the early 1970s. This waste plastic soaks up other pollutants at up to a million times the concentration in water, harming and killing sea life worldwide. From the point of view of the plastic, we have convincingly failed with solutions. Over the past 40 years the problem has grown around 100 times, with now over 8 million tonnes of plastic waste added to oceans per year.

Everyone is aware about ways for plastic to not become waste. We can set up redesign, sharing, refill, recycling and even composting. When it comes to creating practical possibilities for not making waste, people are super smart. But when it comes to making policy to install this practice throughout the economy, which has been the aim of circular economy for the past four decades, we’re consistently collectively stupid. I call this mob thinking.

We have intelligent activists, business people, experts and officials unintentionally thinking like a mob? always bringing forward the same decades old policy weapons. When these weapons don’t work there is a discussion about strategy but not any actual new strategy, just talk about how forcefully to use the same old policy weapons. This is how it’s been possible for waste management, waste regulation and the unsolved waste problem to all grow in tandem for so long.

If the piece of plastic had a voice in the circular economy debate what might it say? It would remind us to beware mob thinking. Today’s problems are solvable only by trying new thinking and new policy weapons. Precycling is an example. The piece of plastic doesn’t mind whether it’s part of a product that’s longlife or refilled or shared or refurbished or recycled or even composted (so long as it’s fully biodegradable). It doesn’t even mind being called ‘waste’ so long as it’s on its way to a new use. Action that ensures any of these is precycling.

Our piece of plastic does mind about ending up as ecosystem waste. It does not wish to join 5 trillion other pieces of plastic abandoned in the world’s oceans. It would be horrified to poison a fish or starve a sea bird. Equally it does not want to be perpetually entombed in a landfill dump or transformed into climate destabilising greenhouse gases by incineration.

The two possible outcomes for a piece of plastic, remaining as a resource or being dumped as ecological waste, are the same fates awaiting every product. Our economies and our futures depend on our ambition in arranging the right outcome. The old policy weapons of prescriptive targets and taxes, trying to force more of one waste management outcome or less of another, are largely obsolete. Circular economy can be fully and quickly implemented by policy to make markets financially responsible for the risk of products becoming ecological waste. Some ever hopeful pieces of plastic would be grateful if we would get on with doing this.

Reference: Governments Going Circular best practice case study of precycling premiums

Note: The original article is available at this link.

Food Waste Management and Anaerobic Digestion

Food waste is one of the single largest constituent of municipal solid waste stream. In a typical landfill, food waste is one of the largest incoming waste streams and responsible for the generation of high amounts of methane. Diversion of food waste from landfills can provide significant contribution towards climate change mitigation, apart from generating revenues and creating employment opportunities.

Of the different types of organic wastes available, food waste holds the highest potential in terms of economic exploitation as it contains high amount of carbon and can be efficiently converted into biogas and organic fertilizer. Food waste can either be utilized as a single substrate in a biogas plant, or can be co-digested with organic wastes like cow manure, poultry litter, sewage, crop residues, abattoir wastes etc or can be disposed in dedicated food waste disposers (FWDs). Rising energy prices and increasing environmental concerns makes it more important to harness clean energy from food wastes.

Anaerobic Digestion of Food Wastes

Anaerobic digestion is the most important method for the treatment of food waste because of its techno-economic viability and environmental sustainability. The use of anaerobic digestion technology generates biogas and preserves the nutrients which are recycled back to the agricultural land in the form of slurry or solid fertilizer. The relevance of biogas technology lies in the fact that it makes the best possible utilization of food wastes as a renewable source of clean energy.

A biogas plant is a decentralized energy system, which can lead to self-sufficiency in heat and power needs, and at the same time reduces environmental pollution. Thus, the benefits of anaerobic digestion of food waste includes climate change mitigation, economic benefits and landfill diversion opportunities.

Anaerobic digestion has been successfully used in several European and Asian countries to stabilize food wastes, and to provide beneficial end-products. Sweden, Austria, Denmark, Germany and England have led the way in developing new advanced biogas technologies and setting up new projects for conversion of food waste into energy.

Codigestion at Wastewater Treatment Facilities

Anaerobic digestion of sewage sludge is wastewater treatment facilities is a common practice worldwide. Food waste can be codigested with sewage sludge if there is excess capacity in the anaerobic digesters. An excess capacity at a wastewater treatment facility can occur when urban development is overestimated or when large industries leave the area.

By incorporating food waste, wastewater treatment facilities can have significant cost savings due to tipping fee for accepting the food waste and increasing energy production. Wastewater treatment plants are usually located in urban areas which make it cost-effective to transport food waste to the facility. This trend is catching up fast and such plants are already in operation in several Western countries.

The main wastewater treatment plant in East Bay Municipal Utility District (EBMUD), Oakland (California) was the first sewage treatment facility in the USA to convert post-consumer food scraps to energy via anaerobic digestion. EBMUD’s wastewater treatment plant has an excess capacity because canneries that previously resided in the Bay Area relocated resulting in the facility receiving less wastewater than estimated when it was constructed. Waste haulers collect post-consumer food waste from local restaurants and markets and take it to EBMUD where the captured methane is used as a renewable source of energy to power the treatment plant. After the digestion process, the leftover material is be composted and used as a natural fertilizer.

The first food waste anaerobic digestion plant in Britain to be built at a sewage treatment plant is the city of Bristol. The plant, located at a Wessex Water sewage works in Avonmouth, process 40,000 tonnes of food waste a year from homes, supermarkets and business across the southwest and generate enough energy to power around 3,000 homes.