CASE STUDY: Waste Management in Buciniland

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CASE STUDY: Waste Management in Bucciniland
Overview: You are members of the Senior Technical Advisory Board to the Ministry of the
Environment for the populous and rapidly industrializing coastal nation of Bucciniland.
Bucciniland has recently ratified the Stockholm POPs Convention and is hard at work on its
national action plan for addressing the unintentional POPs listed in Annex C. You have been
asked to advise the Ministry on the appropriate implementation strategy for the open waste
burning and incineration categories. In particular, your task is to recommend to the government
what should be considered the best available techniques (BAT) and best environmental practices
(BEP) for these categories of sources.
Background:
Bucciniland is in transition from a primarily agrarian economy to a mix of agricultural
and industrial specialties. The interior of the island is well-suited for growing sugar cane, many
types of grain, and timber for export. Industries, particularly light manufacturing and a
burgeoning semi-conductor business, have tended to locate in the low-lying coastal areas
adjacent to a small number of deep water ports. The capital city of Johnsville boasts the best
harbor, has the largest concentration of industrial facilities, and houses almost 60% of the
nation’s 5 million inhabitants.
While the economy has been growing at a steady rate, the infrastructure of the country
has not kept pace. Outside the metropolitan area of Johnsville, good roads are a rarity and
electrification is just now reaching many parts of the interior. A single rail line was built from
the heavily forested center of the country to Johnsville in 1980 to transport timber to the port.
The rapid growth of the economy has led to a dramatic increase in demand for consumer
products. Imports of appliances, clothing, household goods, construction materials and luxury
items are at an all time high and a “disposable” society mentality is beginning to take hold. New
construction, as well as the demolition of older buildings and homes, is a common sight in the
cities.
Waste Management Practices:
Traditional waste management in Bucciniland has been by “town dump” or backyard
burning. Dumps receive all manner of wastes and are periodically burned to reduce volume (or
may spontaneously combust and perpetually smolder). Crop residues and stubble are regularly
burned off to reduce insect pests and prepare for the next planting, and prescribed burning is a
regular practice in forested areas to re-claim land for farming, stimulate forest recovery, or
reduce the likelihood of uncontrolled bush fires.
With the rapid industrialization of Bucciniland, the influx of population to the major
cities, particularly Johnsville, has created a municipal solid waste (MSW) crisis. MSW volumes
have increased dramatically over the past two decades and the composition of these wastes has
changed considerably. The Johnsville “Mount Trashmore” landfill now rivals the tallest
buildings in the city.
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The Johnsville Metropolitan Waste Authority, in 1993, initiated voluntary recycling
programs for aluminum, glass, and newsprint which have had some beneficial effect on waste
volume (reducing the annual growth rate from 10% to 8%); but in the absence of adequate
markets for the recycled materials, most have ended up in large stockpiles that are only slightly
less unsightly than the landfill.
Another unsettling event was the discovery in 1995 that waste solvents and other toxic
chemicals were leaching from the unlined landfill into Johnsville’s groundwater supply. The
problem was made worse by the presence of a shallow water table in most of the coastal areas.
This finding led the government to announce the near-term closure of the landfill and to
hurriedly negotiate the purchase, at the cost of US $200 million, of a large MSW incinerator.
The landfill, which was closed and capped when the incinerator began operation in 1998, has
now had to be re-opened to accommodate an increase in waste volume that has outstripped the
incinerator’s rated capacity.
Although the Environmental Ministry has established guidelines defining hazardous
wastes, and requires that such wastes be kept separate from other municipal and household
wastes, there are currently no dedicated facilities available on the island for hazardous waste
treatment and disposal. Some industries dispose of such wastes in captive incinerators. Others
provide fuel grade wastes (e.g., spent solvents) to local cement kilns or store the materials onsite. A small proportion of these wastes, however, appear to be entering the country’s municipal
waste stream.
Medical wastes (including pathogenic wastes) are generally disposed of in incinerators
adjacent to the island’s hospitals and medical centers. These incinerators are typically small,
single chamber, batch units that handle all of the trash collected at the center and are operated by
the custodial staff. Ashes are disposed of local landfills. Some unincinerated medical wastes
(including sharps) have been found in MSW landfills but the amount is small.
The government of Bucciniland mandated in 1996 that future MSW disposal throughout
the country must either be accomplished through the construction of lined sanitary landfills or
controlled incineration, and set a deadline of 2006 for implementation. Some of the larger
villages have invested in small, batch operated, modular incinerators. Either alternative,
however, is beyond the financial reach of most of the small villages in the interior and the
government’s deadline seems unlikely to be met.
The government has also initiated a public awareness campaign to try to reduce the
amount of backyard trash burning. This program has met with some success, but has placed
even more stress on the existing municipal collection and disposal systems. The Ministry has
also attempted to persuade farmers and foresters to limit the amount of open burning of
agricultural residues forested areas but with little success.
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Relevant Data:
National POPs Inventory. As a part of its national action plan to meet the obligations
of Article 5 of the POPs convention, the Environmental Ministry has recently completed an
inventory of estimated releases of the unintentional POPs from the categories of sources
identified in Annex C. The inventory has identified open burning, including the burning of
landfills, and MSW and medical waste incineration as potentially significant sources of
unintentionally produced dioxins and furans. The inventory also forecasts that these releases will
increase with further industrial and population growth, unless current waste management
practices change.
Johnsville Incinerator. In 2004, the Environment Ministry completed a technical study
of the MSW incinerator in Johnsville. The incinerator is a continuous feed moving grate
incinerator composed of 2 units each with a capacity of 1,000 metric tons of waste throughput
per day. The energy recovered from the incineration process is sufficient to meet 25% of the
electricity demand in the capital. The facility was designed to accommodate 2 additional units of
the similar size but these have not been constructed due to budget limitations.
The waste feed is primarily MSW but includes a small amount (<2%) of hazardous and
medical waste. Based on the Ministry’s testing, the incinerator routinely operates at a
combustion temperature of 900°C with a residence time of 2 seconds. Flue gases are treated to
remove acid gases and particulate matter through a combination of wet scrubbers, cyclones, and
electrostatic precipitators. The latter are operated at a temperature of 220°C. The residues
(bottom and fly ash) are combined and transported in open trucks to the Mount Trashmore
landfill. Measurement of dioxins in the stack gases ranged from 0.05-0.5 ng TEQ/Nm3.
Rural Incinerators. Although sufficient funds were not available to test any of the 150
small modular incinerators scattered through the smaller urban and rural areas of the country, the
Environment Ministry was able to conduct a qualitative survey during 2004. The survey found
that, while a few of these units included a secondary combustion chamber, most were single
chamber batch incinerators operated by the same individuals who had previously served as
custodians for the town dumps.
Medical Waste Incinerators. As with the rural incinerators, funds were not available
for testing the hospital incinerators but application of the emission factors in the POPs Toolkit
identified these sources as being of concern. A qualitative study revealed that many of the
incinerators continued to smolder for several hours after being fired and that the exhaust stacks
were often adjacent to the air exchange systems for the hospitals.
Alternative Approaches to Incineration. In early 2005, an expert group commissioned
by the National Academy of Technology met to examine alternatives to waste incineration,
particularly those that were not considered to lead to the formation and release of the
unintentional POPs. The group concluded that, while there were many promising technologies
under development, the full environmental and economic dimensions of most were not well
understood and few could be considered sufficiently demonstrated on a scale that would permit a
rapid transition in the larger municipalities. The group noted, however, that several pilot
demonstrations of autoclaving and other non-incineration technologies had been successfully
applied to treat hazardous, medical and MSW and encouraged their consideration in future
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decisionmaking. The group also stressed that waste minimization, source separation, and recycling and re-use initiatives merited further investment, regardless of the final disposal option
selected.
Waste, Agricultural, and Forestry Open Burning Practices. The Ministries of
Agriculture and Environment collaborated on a study of open burning practices in early 2005.
The study concluded that much of the open backyard burning conducted in the country resulted
in incomplete combustion which, under the right conditions or in the presence of high waste
loads of chlorine or catalytic metals, could result in significant formation and release of
unintentionally formed POPs. The study recommended that, at a minimum, the government
establish guidance on ways to minimize releases from open burning and undertake a public
awareness campaign.
Questions for the Senior Technical Advisory Board:
1. Recognizing the particular circumstances in which Bucciniland finds itself and the
available information, how would you recommend the Environmental Ministry
address the following questions:
a. Does the existing large MSW incinerator meet the requirements for BAT? If
not, what changes/improvements would be necessary?
Answer: No. Separate haz and med waste from normal MSW. Scrubbers need
to operate at below 200°C. Bottom & fly ash are not separated and fly ash is not
treated (see MWC section 12.3, p 76). Need to establish dedicated facility to deal
with hazardous waste and divert medical/infectious waste to existing
incinerators.
b. Do the existing rural incinerators represent BAT for these areas? If not,
what changes/improvements would be necessary?
Answer: two combustion chambers yes, one combustion chamber no. In both
cases it is not apparent that operators are sufficiently trained to operate units
efficiently and correctly.
c. Do the existing medical waste incinerators meet BAT? If not, what
changes/improvements would be necessary?
Answer: Operating parameters not being met if smoldering is occurring. What
about source separation of non-medical/infectious waste? Location increases
exposure. Need to relocate to minimize exposure.
d. In considering non-incineration alternatives to the construction of new
incineration facilities (including any facilities to treat and dispose of
hazardous waste), what kinds of issues would need to be addressed?
Answer: cost, availability, technical feasibility (including operator training,
maintenance of equipment), accessibility (see Annex F)
2. What improvements in best environmental practices (BEP) would you recommend
for:
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a. Generation, collection, handling and disposal of MSW
Answer: Develop markets for recycled materials; internalizing costs of waste
disposal via fees;
b. Open waste burning (including backyard burning and smoldering landfills)
Answer:
c. Open agricultural and forestry burning
Answer: Develop markets for recycled materials; internalizing costs of waste
disposal via fees;
d. General waste management practices
Answer: Source reduction/minimization; material recovery and recycling;
composting of compostibles; raising awareness about waste; Develop markets
for recycled materials; internalizing costs of waste disposal via fees;
3. What challenges do you think Bucciniland will face in meeting its waste
management obligations under Article 5 for these categories of sources?
Answer: ensuring proper operation of incineration facilities; dealing with growing
amounts of waste; infrastructure to separate and deal with haz and medical waste;
discouraging open burning;
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