Commercial and Industrial Waste and Selected Wasteflows
3. Four important challenges for commercial and industrial waste
3.1 Large amounts of waste
3.2 Recycling
3.3 Hazardous waste
3.4 Environmental contaminants
In this chapter, the four important challenges associated with commercial and
industrial waste will be described in more detail. These apply to the large amounts, the
need for recycling, hazardous waste, and environmental contaminants.
3.1 Large amounts of waste
Amounts
In 1995, approximately six million tonnes of commercial and industrial waste were
generated; 2.6 million tonnes from industry, 0.8 million tonnes from trade, offices and
institutions, and 2.6 million tonnes from building and construction. In addition, 1.7
million tonnes of residues were produced from coal-fired power stations, 0.5 million
tonnes residues from waste incineration plants, and approximately one million tonnes of
sludge from sewage-treatment plants.
The different fractions
In Table 1, the different waste fractions of commercial and industrial waste are
outlined by sector. Industry, and building and construction are the largest contributors
and each produces about 30 per cent of all commercial and industrial waste. Residues from
coal-fired power stations comprise about 20 per cent, while waste from sewage-treatment
plants, and institutions, trade and offices each comprise 10 per cent.
It is seen that a large part of the waste which is produced can be broken down into
unique waste fractions which indicate something of the nature of the waste. For the
fractions sundry suitable for incineration and sundry not suitable for
incineration, which comprise about 15 per cent of commercial and industrial waste,
it is not possible to determine anything precise about the nature of the waste. On the
whole, however, this analysis is considered satisfactory enough to be able to identify
waste fractions for which initiatives must be established in the form of minimising the
amount of waste or increasing recycling.
Tabel 3.1
Economic growth increases the amount of waste
Economic growth and therefore greater consumption will, all other things being equal,
increase the amount of waste. This link has not only been ascertained in Denmark, but also
throughout the EU. It has not been possible to delink economic growth, and growth in the
amount of waste.
Need for many different initiatives
Clean technology, environmental management, recycling products and packaging,
improvement of product quality in respect of durability, better possibilities for repair,
increased recycling of components in spent products, etc. all other things being equal
reduce the amount of waste. Efforts to minimise waste are characterised by the need for
many different initiatives to achieve a visible result.
Quality control
In recent years, many enterprises have introduced various forms of certified quality
control, for example ISO or DS. However, quality control has primarily been directed
towards the quality of the product and fulfilling customer expectations, i.e. ensuring a
specific level of quality and identical products. Quality assurance does not always take
account of the consumption of resources and waste in connection with the production
process, such as the number of rejected units in production and the materials wasted. In
order to achieve a product with the desired quality, some enterprises have increased their
reject rate.
Environmental management
With the aid of environmental management systems, eg. BS 7750, however, focus is put
on enterprises consumption of resources such as waste generation, and energy and
water consumption.
An enterprises work with quality control, for example, can also advantageously
involve attention to production waste. Small changes in behaviour in daily operations can
offer savings in resources and economic advantages for enterprises, without significant
investment.
Clean technology
Efforts in this area are connected with clean technology, environmental management
and quality control, including the organisation of production processes. It implies that
efforts to minimise waste are based on the recommendations and guidelines which appear in
the guidelines, reviews and surveys etc. published by the Environmental Protection Agency.
The Environmental Protection Agencys Position Paper Intensified
Product-oriented Environmental Action is a supplementary tool to minimise waste
from, eg. rejected products, and the Industry Report is a tool for minimising production
waste.
The effect is evident after several decades
With the introduction of clean technology, substitution of environmental
contaminants, and environmental management, action is taken at source, i.e. in the
production phase. However, these efforts will first have an effect on waste in the longer
term. For example, it takes a long time to introduce clean technology and substitution in
all phases, and the products lifetime decides when it will be found in the
waste-flow. Efforts at source will, therefore, only be measurable after several decades.
Economy controls the choice of production process
It must also be faced that recommendations and the setting out of guidelines will not
in themselves lead to waste minimisation, as it is to a large extent economy which
controls the choice of a production process. The economic cost of waste disposal is
therefore an important incentive for enterprises to reduce the amount of waste produced.
Economic behaviour-regulating measures and systems which make the costs of waste disposal
visible, for example, the introduction of environmental management and green accounting,
are thus important factors in minimising waste. In addition, taxes and charges on waste
have an impact on waste generation.
3.2 Recycling
A number of initiatives which are mentioned in the Action Plan on Waste and Recycling
1993-97, have not yet been implemented, or have taken full effect - amongst others,
take-back schemes for transport packaging and electrical and electronic products. When
this has taken place, it will lead to an increase in recycling but this will only partly
find a corresponding fall in landfilling, as today a large proportion is incinerated.
Prerequisite for achieving objectives
There are two important prerequisites which must be fulfilled before it is possible
to achieve the objectives for recycling. First, there must be a market for the recyclable
products. Secondly, it must be ensured that there is waste to be recycled.
However, waste is only suitable for recycling if it constitutes products which can
continue to be recycled. If recycling results in a new product of reduced quality, for
example poor durability, then recyclability in the next phase is destroyed. Similarly, if
the new product cannot be recycled for some other reason, then this cannot be considered
as recycling, but merely postponement of waste disposal.
Separation of environmental contaminants
When recycling hazardous waste, or recycling waste containing environmental
contaminants, particular attention must be paid to separation of the environmental
contaminants so that they are taken out of the cycle. For example, it is necessary to
remove batteries from end-of-life vehicles before they are scrapped. In this way, car
scrap is not contaminated with lead from batteries.
Closed cycle
Alternatively, recycling can be kept in closed cycles. Today, nickel-cadmium
batteries are recycled in closed cycles where the batteries are collected and reprocessed
at special plants and subsequently incorporated in new batteries.
As mentioned above, there is a need for special efforts to increase recycling from
trade and offices. A large part of the waste generated by this sector is paper, cardboard,
and plastic. These waste fractions are suitable for incineration, but are also highly
suitable for recycling. The Transport Packaging Agreement will contribute to increased
efforts for these fractions. Within other sectors there will possibly also be waste
fractions which can be recycled to advantage, whereas today they are incinerated.
The Danish business structure
Denmark is characterised by a business structure comprising many small and
medium-sized enterprises, and in many municipalities a certain sector is only represented
by one or two companies. It can be difficult administratively and economically for
producers, waste companies or administrative authorities to manage waste in such a way
that it is possible to recycle it. Although the effects of business regulations have not
yet become fully evident, it should be considered whether recycling waste from certain
sectors would be promoted if cooperation could be established within sectors, in larger
regions, within waste companies or in other larger units, or by establishing national
schemes.
The need for imports and exports
In certain cases, there is too little of a recyclable waste fraction in Denmark to
ensure the supply and economic foundation required for a recycling enterprise. For
example, this applies to certain types of plastic, and some types of hazardous waste. By
entering into cooperation with other Nordic countries or other EU countries, optimal
recycling of waste can be achieved. This may mean that a waste fraction must be imported
to Denmark, or exported for recycling abroad.
Over the last ten years there has been considerable growth in the amount of waste from
discarded products both in the consumption phase, and in industry. At the same time,
technological developments have led to many products becoming more complex.
Complex products
Complexity is evident in materials and combinations of materials, advanced surface
treatments, production of single-use products which are difficult or impossible to
separate, etc. The consequence of this development is that the possibilities for recycling
are limited, which leads to increasing demands on the recovery industry. There is, thus, a
need to develop technologies which can break down, separate, manage, etc. products that
are today discarded.
In order to reduce the problems which arise from the complexity of new products,
demands should be placed on the composition of new products. If the complexity of waste is
to be reduced in the future, and if it is to be possible to better manage complex waste
than at present, there must be new forms of cooperation between manufacturers, waste
collectors, waste-treatment enterprises, and the authorities. Such cooperation must
contribute to waste recycling and disposal being considered during product development.
These issues are also addressed in the Position Paper Intensified Product-oriented
Environmental Action.
3.3. Hazardous waste
Regulations on hazardous waste
Hazardous waste differs from other waste in that there can be fire, health or
environmental hazards to consider when managing hazardous waste. Table 2 outlines the
characteristics which make waste hazardous. Regulation of hazardous waste is through EU
directives and was transposed to Danish legislation in summer 1996. This replaced
regulation on oil and chemical waste.
The composition of waste
The composition of waste determines the extent to which it is a burden on the
environment. If a waste fraction contains hazardous substances, the waste itself may be
hazardous, depending on how much of the hazardous substances occur, and how firmly bound
the hazardous substances are to the waste.
Registration of hazardous waste
Hazardous waste must therefore be registered and, as a point of departure, must be
collected by the municipality which is responsible for the disposal of hazardous waste.
Special registration and collection of hazardous waste must ensure that hazardous waste is
not managed and disposed of inappropriately, causing hazards to the environment and the
population.
Disposal according to a specific assessment
How hazardous waste is disposed of is determined by a specific assessment of the
composition of the waste and its characteristics, taking account of the waste disposal
plants which are available.
Upon incineration, the nature of waste changes. Waste which was originally hazardous
can be converted to non-hazardous components. For example, this applies to some organic
solvents. In contrast, non-hazardous waste can generate hazardous residues;
this applies, for example, to PVC which generates acidic flue-gas cleaning products.
Some waste fractions contain environmental contaminants. This need not imply that such
fractions are hazardous waste. Contaminants can be present in low concentrations, for
example. However, the waste fraction can create environmental problems upon landfilling,
or incineration, particularly if the waste fraction occurs in large amounts. This applies
to impregnated wood, for example.
Upon incineration, environmental contaminants are transferred to residues. Some
contaminants can subsequently be released into the environment, for example, through
leaching. When landfilling there should assessments on whether the environmental
contaminants could leach.
Some types of waste can be recycled, eg. oil. Other types can conveniently be collected
and treated separately with a view to recovering, eg. heavy metals. This applies to lead
batteries and photographic agents, for example.
Hazardous waste, eg. solvents, can in some circumstances be incinerated in conventional
waste incineration plants, whereas other types of waste require special treatment, for
example at Kommunekemi A/S.
Table 2. Outline of characteristics which make waste hazardous
Fire hazard |
· explosive · inflammable
· highly inflammable |
Environmental hazard |
· aquatic env. · other eco-systems |
Health hazard |
· toxic
· harmful to health
· corrosive
· locally irritant
· allergenic
· carcinogenic
· mutagenic
· causes infertility
· contagious |
Other |
· waste which on contact with water, air or acid emits toxic
or highly toxic gas.
· waste which on disposal can result in other substances, eg. a leachate with one of the
above characteristics |
Just as for all other waste, the decisive factor for disposal is that the waste is
disposed of in a manner which offers the best possible protection for health and the
environment, the best possible recycling of residues, and the best possible recovery of
energy and raw materials.
The establishment of Kommunekemi A/S in 1972 and a collection system for hazardous
waste has meant that for many years Denmark has had environmentally sound management and
disposal of hazardous waste. However, most of the waste is incinerated or landfilled.
Awareness of developing methods which better promote utilisation of raw materials,
including recovering environmental contaminants in hazardous waste has not been prevalent.
Less waste to Kommunekemi A/S
Over recent years, Kommunekemi A/S has noted a fall in the amount of waste received.
According to Kommunekemi, this is partly due to enterprises adopting clean technology, and
that there is more and more recycling of certain profitable fractions.
Another aspect is that more incineration plants are able to treat oil and chemical
waste, and hazardous waste. Thus, today there are more municipalities which dispose of
hazardous waste at plants other than Kommunekemi A/S. This is also a consequence of new
regulations for hazardous waste which state, for example, that waste can be hazardous for
the single reason that it is inflammable. This means that disposal of inflammable waste
may occur at conventional incineration plants.
253,000 tonnes of hazardous waste per year
In 1995, the total amount of hazardous waste in Denmark amounted to over 253,000
tonnes, see Table 3. This information originates from Kommunekemi A/S, ISAG (Information
System of Waste and Recycling), other hazardous waste disposal plants, and export
statistics. The table is partly made up from information which covers the amounts produced
(other types), and partly from amounts which Kommunekemi A/S received in 1995.
The Environmental Protection Agency assesses that these combined amounts offer a
representative picture of the amounts of hazardous waste which are generated in Denmark.
Table 3 outlines how hazardous waste is distributed over various waste fractions, and
the largest waste fractions received by Kommunekemi are specified. The Environmental
Protection Agency is in possession of detailed information on the types of waste included
in other waste received at Kommunekemi. However, these waste types are all
received in amounts of less than 1,000 tonnes per year, and are therefore not analysed
more specifically here.
Need for special efforts for small and medium-sized enterprises
The waste fractions mentioned in Table 3 come from large enterprises, as well as many
small and medium-sized enterprises. Continued reductions in the total amount of hazardous
waste require that special efforts are also made for small and medium-sized enterprises to
spread clean technologies, or establish special collection, and separate treatment schemes
if recycling of waste is to be promoted. This applies to the graphic and galvanising
sectors, for example.
Waste taxes for hazardous waste
Hazardous waste is exempted from waste taxes. This is to avoid further incentives to
dispose of hazardous waste by mixing it with other waste, as well as the incentives which
the higher costs of disposing of hazardous waste bear in themselves. Treatment costs for
hazardous waste have hitherto generally been significantly higher than costs for other
waste.
However, the costs of disposal of hazardous waste vary considerable today, depending on
the type of hazardous waste under consideration. The costs of disposing of certain types
of hazardous waste are no higher than for normal waste.
The basis for exempting hazardous waste from taxes has therefore changed and the
question is now, how far imposing taxes can contribute to limiting the amount of hazardous
waste, encourage further use of clean technology, and possibly increase recycling.
Table 3. Outline of hazardous waste fractions generated in 1995
Hazardous waste |
|
|
|
Received at Kommunekemi A/S 1995 |
Waste type |
Amount
(tonnes) |
Total |
|
Washing and cleaning agent waste |
1619 |
|
|
Aromatic organic solvents |
4380 |
|
|
Other organic solvents |
2448 |
|
|
Printing dyes, paint, varnish, etc. with org. solvents |
6472 |
|
|
Liquid organic residues from distillation |
3154 |
|
|
Anti-freeze |
1039 |
|
|
Acidic solvents, aqueous |
5023 |
|
|
Photographic developing baths |
7186 |
|
|
Alkali aqueous solvents |
3045 |
|
|
Metal hydroxide and metal oxide sludge |
5509 |
|
|
Smoke-cleaning sludge & smoke-filter dust |
2415 |
|
|
Waste from prod. etc. of pesticides |
1050 |
|
|
Medical waste |
1012 |
|
|
Chemical waste from laboratories etc. |
1650 |
|
|
Oil waste |
16709 |
|
|
Other waste received at Kommunekemi |
29549 |
|
|
Total |
|
92260 |
Other types of hazardous waste, not treated at Kommunekemi
A/S, 1995 |
|
|
|
|
Primary sources |
|
|
|
Hospital waste |
11400 |
|
|
Lead batteries |
12282 |
|
|
Nickel-cadmium batteries |
120 |
|
|
Sulphuric acid |
22000 |
|
|
Waste oil delivered to district heating plants |
19200 |
|
|
Oil & chemical waste from other primary sources |
15200 |
|
|
Asbestos |
7300 |
|
|
Total |
|
87502 |
|
Secondary sources |
|
|
|
Filter dust from flue-gas cleaning |
9991 |
|
|
Flue-gas cleaning products (waste incineration) |
63300 |
|
|
Total |
|
73291 |
Tot. haz.waste |
|
|
253053 |
3.4 Environmental contaminants
Harm to the environment and people
Environmental contaminants include substances which occur naturally, and substances
which are artificial. They are substances which, if present in unnaturally high amounts,
will harm the environment and people. Environmental contaminants comprise, in themselves,
a raw material resource. Some environmental contaminants are also characterised as being
limited raw materials resources.
Table 4. Selected environmental contaminants and their effects on the
environment and health
Arsenic and arsenic compounds |
· Harmful to the aquatic env
· Bio-accumulate in the food chain
· Carcinogenic
· Highly toxic |
Copper compounds |
· Harmful to the aquatic env.
· Harmful to health |
Lead and lead compounds |
· Harmful to the env.
· Accumulate in the food chain
· Carcinogenic
· Neuro-toxic
Toxic to reproduction |
Mercury and mercury compounds |
· Harmful to the aquatic env.
· Highly toxic
· Neuro-toxic
· Accumulate in the food chain |
Cadmium and cadmium compounds |
· Harmful to the aquatic env.
· Accumulate in the food chain
· Carcinogenic
· Highly toxic |
Nickel and nickel compounds |
· Allergenic
· Carcinogenic |
Chromium compounds |
· Harmful to the env.
· Highly toxic
· Carcinogenic
· Allergenic |
Phthalates |
· Harmful to the aquatic env. |
The most harmful environmental contaminants
In 1991, the Environmental Protection Agency established the Framework
programme for limiting environmental contaminants in waste, residues, and recyclable
materials, which was to indicate the most harmful contaminants in the waste flow,
and identify important sources of such waste.
The programme has included analyses of emissions from incineration plants, landfills
and composting plants for domestic waste and normal commercial and industrial waste in
Denmark. That is to say, oil and chemical waste (hazardous waste) and other special waste
delivered to special plants such as Kommunekemi A/S were not included in the analysis.
The Framework Programme has indicated a number of the most harmful contaminants found
in residues from incineration plants. These include the heavy metals lead, mercury and
cadmium, which are well known as environmental contaminants due to their toxicity in all
recipients. However, nickel, chromium, copper, half-metallicised arsenic, and organic
substances such as phthalates can also give rise to environmental and health problems
shown in Table 4.
Mass-flow analyses
In order to have an impression of where environmental contaminants originate and
where they end up, the Environmental Protection Agency has commissioned mass-flow analyses
for the most harmful substances. The analyses show which waste fractions contribute heavy
metals, and how different heavy metals are distributed in different disposal methods such
as landfilling, incineration, at Kommunekemi A/S, or as waste-water sludge. Furthermore,
they show the amount contributed to the overall burden by different products or processes.
Amount of heavy metals in different forms of disposal
Table 5 provides an overview of the amount of a number of selected heavy metals
delivered to different forms of disposal. The figures are the best estimates the
Environmental Protection Agency could attain, based on various surveys. The uncertainty of
the various estimates is therefore different. It appears that waste fractions which
contain environmental contaminants are primarily delivered to landfills or incineration.
Table 5. Delivery of selected heavy metals (estimated amounts in tonnes/year)
via different forms of waste disposal
Heavy metal |
Deposit/
landfill |
Incineration |
Kommunekemi A/S |
Waste-
water sludge0 |
Arsenic* |
2 |
18 |
unknown |
1 |
Lead** |
880-2,200 |
520 - 1,200 |
99 - 101 |
13 |
Cadmium*** |
2 |
22 |
unknown |
0.7 |
Copper** |
2,500 - 6,000 |
2,300 - 4,400 |
133 |
15 |
Chromium* |
<100 |
200 - 500 |
unknown |
9 |
Mercury** |
0.4 - 1.1 |
1.3 |
0.4 - 1.6 |
0.1 |
Nickel** |
175 - 400 |
350 - 770 |
44 |
3 |
* Estimate based on Orientering fra Miljøstyrelsen nr. 7' Consumption and
pollution of arsenic, chromium, cobalt, and nickel, Environmental Protection Agency
(1985), Environmental project No. XX Wood protection agents and impregnated wood,
Environmental Protection Agency (being printed)
**Mass-flow analyses for lead, nickel, copper, mercury, Environmental Protection Agency
(1996)
*** Consumption and pollution of cadmium, Environmental Protection Agency (1995)
0 Calculated based on measurement of sludge in 1995.
Environmental contaminants disperse in residues
It can be seen from Table 6 how the most harmful environmental contaminants disperse
in residues after treatment in a conventional incineration plant. Dispersion is calculated
in tonnes of heavy metal per year. It is seen that after incineration almost 90 per cent
of heavy metals are bound in slag and fly ash. However, the majority of mercury is to be
found in the flue-gas cleaning product, and cadmium is mostly found in fly ash. The way in
which various heavy metals are dispersed in residues depends on the conditions the waste
is exposed to during incineration. For example, the incineration temperature greatly
influences the result.
Potential risks from residues
The potential risks from using residues cannot, however, be read from the table. When
assessing risks, account should be taken of the actual concentration of heavy metals in
the individual residues, the possibilities for metals being washed out, etc. The risk of
washing out from individual residues is partly dependent on how strongly the metal is
bound to the residue, the acidity to which the residues are exposed when utilised, etc.
Organic substances, in contrast to elements, are to a greater or lesser extent degraded
biologically, photochemically, or, for example, through appropriate thermal treatment
(incineration), so that there is rarely an accumulation of these substances in the
environment from residues from waste incineration.
It can be observed that organic, environmental contaminants are found in far lower
concentrations in residues from incineration plants than heavy metals. Moreover, these
substances disperse in less unique emission types compared with heavy metals. In the
framework programme, DEHP was found in much higher concentrations than other organic
substances. The total contribution from DEHP in residues from incineration plants amounts
to, however, only one tonne per year.
Table 6. Dispersion of selected environmental contaminants in residues from
incineration plants (per year)
Residue |
As |
Cd |
Cr |
Cu |
Hg |
Ni |
Pb |
Zn |
Flue gas |
5% |
3% |
1% |
- |
20% |
4% |
- |
- |
Slag |
45% |
12% |
79% |
95% |
20% |
86% |
71% |
63% |
Fly ash |
45% |
79% |
20% |
5% |
20% |
85 |
26% |
34% |
Flue-gas clng. pro. |
5% |
6% |
- |
- |
40% |
2% |
3% |
3% |
499,000 tonnes of residues - of which 420,000 tonnes slag
In 1995, a total of approximately 499,000 tonnes of residues was produced by waste
incineration plants in Denmark, of which slag amounted to over 420,000 tonnes. Fly ash and
flue-gas cleaning products amounted to more than 60,000 tonnes. The majority -
approximately 80 per cent - of slag is today reused, primarily as road-filling material,
noise barriers, etc. Today, there are no suitable opportunities to recycle fly ash and
flue-gas cleaning products, therefore they are deposited at special sites.
All other things being equal, the amount of residues must be expected to rise in the
future, partly due to the ban on landfilling waste suitable for incineration. Furthermore,
it must be expected that the content of environmental contaminants in residues will
increase well into the future, until the complex nature of waste has changed, and until
clean technology and the substitution of environmental contaminants have fully taken
effect.
There must be fewer environmental contaminants in residues
If waste containing environmental contaminants continues to be disposed of at
conventional incineration plants, these substances will continue to spread in all
residues. If opportunities to recycle slag are to continue, special efforts are necessary
to reduce the delivery to incineration plants of waste fractions containing large amounts
of environmental contaminants.
From the point of view of saving resources, and based on a desire to keep resources in
the cycle, in some situations it will be advantageous to exploit the resources of raw
materials to be found in waste through recovery. This will take account of non-renewable
resources. However, this will place demands on waste-treatment methods.
Leachate from landfills
Environmental contaminants in waste which are landfilled, will, to a large extent,
end as leachate from landfills. Treating the leachate will imply that non-biodegradable
substances end in waste-water sludge.
|