Waste management Flashcards
what are 4 difficulties of locating a lanfill site
1- planning permission is required which will stall the construction of the landfill site for possibly many years
2- A permit is required for operation to ensure all proper surveys have been carried out, this is time consuming and adds to up front costs
3- There may be objections by local residents due to odor and eyesore, this will delay planning permission being issued and subsequent permits
4- Suitable transport links are required to ensure the contents can be carried to the site in hgv’s
what are 6 issues in development in a landfill site
Once a permit / licence has been granted it takes a further 18 months
from the beginning of construction to operation adding to up-front
investment costs.
* The site must be geographically suitable so that the polluting leachates from the site cannot affect the surrounding land and water.
* A detailed site survey is required prior to operation to ensure that the landfill site will not cause movement of the surrounding land.
* An environmental assessment is required to confirm that the effect of the landfill site on the local environmental is minimal.
* The landfill must include leachate and landfill gas treatment measures to
minimise water and air pollution.
* Leak detection is required as flammable methane gas can be released.
Methane gas is a greenhouse gas.
How is NI Over reliant on landfill sites
The management of waste contributes directly to climate change through
emission of GHG from landfill sites and energy use. Overall, waste emissions
account for around 3% of the UKs GHG emissions. The latest NI C&I survey published in 2011, which covered the year 2009,
estimated that there was almost 1.3 million tonnes of C&I waste collected
in NI, 0.8 million tonnes of which was from the industrial sector and 0.5 million
tonnes from the commercial sector.
What are 5 major waste types
- Municipal waste
- Commercial and industrial waste.
- Construction, demolition and excavation waste.
- Hazardous waste.
- Agricultural waste.
what is municipal waste
muncicipal waste - Means waste from households and other waste which is similar in nature to waste from a household. This includes C&I waste which is similar in
nature to waste from a household.
what is commercial and industrial waste
commercial and industrial waste - Mostly means waste from premises used wholly or mainly for the purposes of a trade of business, sport, recreation or entertainment.
what is construction, demolition and excavation waste
- Means waste from construction or demolition works, including
waste from preparatory works.
What are the complications with hazardous waste
There is a restriction on the use of hazardous substances in electrical and
electronic equipment (EEE) and EU directives aims to protect human health
and the environment by minimising the amount of potentially hazardous
substances ending up in landfill sites and recycling processes. The restricted
substances include lead, cadmium and mercury.
What are the priority waste under EU legislation
1-Packaging
2- Waste Electrical & Electronic Equipment (WEEE)
3-End of life Vehicles
4-Tyres
5-Batteries and accumulators
6-
What are the European waste management policys
1-EU waste framework directive (WFD) requires establishments of waste management strategies and plan.
2-EU landfill directive, aims to prevent or reduce as far as
possible negative effects on the environment from the landfilling of waste.
Give 2 examples where NI waste management influenced by the EU
Example 1 - The requirements of the revised WFD have been transposed into NI legislation through the Waste Regulations (NI) 2011.
Example 2 - NI Waste Management Strategies to date; NI Waste Management Strategy (WMS) 2000 first published.
NI WMS 2006 – Reflects move away from simply managing the waste
we produce in a more environmentally friendly manner to preventing
waste and managing resources.
What is the purpose of the waste management hierarchy and when was it introduced
The primary purpose of the waste hierarchy is to minimize adverse affects and to increase resource efficiency in waste management policy.
The hierarchy was introduced in 2011 in the waste regulation NI 2011
What does the waste management hierarchy contain from top to bottom
Prevention
Preparing for re-use
Recycling
recovery
disposal
what is the purpose of the hierarchy
The primary purpose of the hierarchy is to minimise adverse environmental
effects from waste and to increase resource efficiency in waste management
and policy.
What is prevention in the waste management hierarchy
Trying to reduce the creation of waste by
1-Sourcing materials locally – incorporation into construction contracts that
materials such as concrete, aggregate steel e.t.c are to be sourced locally
2- Dealing with waste locally - The Proximity Principle highlights a need to
treat and/or dispose of wastes in reasonable proximity to their point of
generation.
3-ceating legislation which will promote sustainable options, promote ecodesign (with re-use at the end of service life in mind).
4- Producers responsiblilty scheme - makes producers manufacture products in a more sustainable manner
5-Governement initiatives- make governments think more green like using a carrier bag levy
what is preparing for reuse in the waste management hierarchy
This is checking cleaning and preparing products and comonents that have become waste to be reused.
Example of products
1-Electrical equipment
2-furniture
3-bikes
4-paint
5-clothes
What is Reclycling in the waste management hierarchy
This involves manufacturing products with recyclable material and it also incoporates the use of the brown and blue bin. High qaulity recycling is important as it help to maximise the use of materials and thier economic value making products more sustainable
what is energy recovery in the waste management hierarchy
Waste contains energy and one way to extract this waste is by incineration however burning plastics and other maaterials can release harmful gases
what is disposal in the waste management hierarchy
using a traditional landfill site is the disposal aspect however it is a last resort
what is a MRF
Material recovery facility
what happens in a MRF
After we segregate are rubbish into different bins it goes to an MRF where it is separate further into different groups
what is stage one of MRF
Quality Inspection - To ensure that only those materials required for recycling are moved onto the next stage of the process. The waste material is pushed onto conveyors where it first enters a pre-sort cabin. Here personnel
remove any unwanted items.
whats stage two of MRF
Separation this is where a series of technologies are used to separate the waste into their own piles ;
1-over band magnets for steel cans
2-glass bottles and jars are seperated by a screening method to be cleaned
3-PLastic bottles go into a separator and are split into HDPE, PET and unwanted mixed plastic.
Whats stage 3 of MRF
– The separate streams of plastic are sent for quality control before
handling to be punctured and squashed, ready for bailing.
What is a landfill
A structure that is built into or on top of the ground where waste is seperated from the surrounding environment (groundwater, air and rain) which is achieved by a bottom liner and a daily soil covering.
what is a bottom liner system and what is its purpose
The purpose of a bottom liner is to stop trash from coming into contact with the external environment. The bottom liner is made out of synthetic plastic which usually is (PE, HDPE or PVC) an alternative is sanitary landfill that uses clay
how doe a leachate collection system work in landfill
Leachate is allowed to run down the bottom liner system to where pipes with holes in them are held. These pipes then run the leachate out to a sump then the leachate can be ran to a collection pond. The leachate is then tested for chemicals and after this it is treated like any other sewage .
what is leachate
Leachate is generally water that has come of waste and runs down through the landill which is black in colour and acidic
how does storm water drainage systems work
It is important to keep landfill as dry as possible and this can be done in two ways:
1-Exclude liquids from the solid waste. Solid waste must be tested for liquids before entering the landfill. This is done by passing samples of the waste through standard paint filters. If no liquid comes through the sample
after 10 minutes, then the trash is accepted into the landfill.
2-Keep rainwater out of the landfill. To exclude rainwater, the landfill has a storm drainage system. Plastic drainage pipes and storm liners collect water from areas of the landfill and channel it to drainage ditches
surrounding the landfills base.
How is methane produced in landfill
Bacteria in landfill breaks down the trash in the absence of oxygen (anerobic) because the landfill is airtight. This produces LFG which is aprox 50% methane 50% CO2
Why and how is methane removed
Methane is 25% more harmful than CO2 and causes a hazard as it is explosive meaning it has to be removed. It is remove by a series of pipes are embedded within the landfill to collect the gas. In some landfills, this gas is
vented or burned. Methane can be used for heating or electricity
What is a bioreactor landfill
Any permitted landfill or landfill cell
where liquid or air is injected in a controlled fashion into the waste mass in order to accelerate or enhance biostabilisation of the waste
what operations does a bioreactor do
A bioreactor operates to rapidly transform and degrade organic waste. The increase in waste degradation and stabilisation is accomplished through the addition of liquid and air to enhance microbial processes
what are the 3 different general types of bioreactor landfill configurations?
1- Aerobic
2- Anaerobic bioreactor
3- Hybrid (aerobic and anaerobic)
How does an aerobic bioreactor work
In an aerobic bioreactor landfill, leachate is removed from the bottom layer, piped to liquid storage tanks, and recirculated into the landfill in a controlled manner. Air is injected into the waste mass, using vertical or
horizontal wells, to promote aerobic activity and accelerate stabilisation.
How does an anaerobic bioreactor work
In an anaerobic bioreactor landfill, moisture is added to the waste mass in the form of re-circulated leachate and other sources to
obtain optimal moisture levels. Biodegradation occurs in the absence of
oxygen (anaerobically) and produces landfill gas. LFG primarily methane, can
be captured to minimise greenhouse gas emissions and from energy recovery.
How does a hybrid bioreactor work
The hybrid bioreactor landfill accelerates
waste degradation by employing a sequential aerobic-anaerobic treatment to rapidly degrade organics in the upper sections of the landfill and collect gas from he lower sections.
what is the primary function of a bioreactor
accelerate the decomposition and stabilisation of waste
How does bioreactor accelearte the decomposition of waste
leachate, stormwater, stormwater drainage treatment sludge is used to enchance the microbiological process.
3 advantages of a bioreactor
Decomposition and biological stabilisation in years vs. decades in a dry
tomb.
Lower waste toxicity due to both anaerobic and aerobic condictions.
Reduced lechate disposal costs.
what is a dry tomb landfill
A try tomb is a fully sealed landfill site. The
waste in maintained in dry conditions to minimise biodegradation and the release of leachate and LFG. a dry tomb has a long life span of 20-30 years.
What is phase 1 of decomposition a dry tomb in landfill
Aerobic biodegradation takes place; oxygen is gradually removed and replaced by CO2
What is phase 2 of decomposition a dry tomb in landfill
Substances such as cellulose, proteins and fats decompose to produce substrates for further biodegradation that provide short fatty acids, CO2 and H2 . This process can take two weeks to become established. During this phase methane bacteria begin to establish themselves in the waste.
What is phase 3 of decomposition a dry tomb in landfill
Landfill gas begins to be produced in significant quantities. This phase takes three to four months to become established. The rate of gas production stabilises within two to three years
What is phase 4 of decomposition a dry tomb in landfill
the sites will produce gas over a long period of time
What are the two catgeories of waste for landfill tax
Inactive waste and active waste
What does inactive waste consist of
materials used in buildings, concrete, brick, glass, soil and gravel. Basically materials
that will not react when buried, giving of harmful GHGs (methane and CO2) or
produce leachate.
What is active waste
waste that produces gas and leachate when being broke down
what are the two types of tax categories and how do these deter users
lower tax bracket which on average is 2.50 per ton. standard rate that is constantly rising year on year at £80/ton which deters people from using landfill as it is so expensive
Within these rates rates active waste is taken into account
is there is 0-10% of active waste within the content you are in the lower tax bracket.
11-100 is in the higher tax bracket.
