Monday, February 15, 2010

Solid Waste Management (RA 9003), Biodegradable-vs-non biodegradable, and other hazardous wastes



[ REPUBLIC ACT NO. 9003 ]

AN ACT PROVIDING FOR AN ECOLOGICAL SOLID WASTE MANAGEMENT PROGRAM, CREATING THE NECESSARY INSTITUTIONAL MECHANISMS AND INCENTIVES, DECLARING CERTAIN ACTS PROHIBITED AND PROVIDING PENALTIES,APPROPRIATING FUNDS THEREFOR, AND FOR OTHER PURPOSES.



In living organisms, waste is the unwanted substances or toxins that are expelled from them. More commonly, waste refers to the materials that are disposed of in a system of
waste management.



Through proper waste management, it can be converted into valuable products by composting, or energy by waste-to-energy processes such as anaerobic digestion and incineration. As part of an integrated waste management system, waste-to-energy processes reduces the emission of landfill gas
Landfill gas;
Production:Landfill gas production results from chemical reactions and microbes acting upon the waste as the putrescible materials begins to break down in the landfill. Due to the constant production of landfill gas, the increase in pressure within the landfill provokes the gas's release
into the atmosphere.
Composting
: converts biodegradable waste into compost. Anaerobic digestion converts biodegradable waste biogas and soil amendment (digestate). Incineration as well as biogas can be used to generate electricity and/or heat for district heating.


The internationally accepted hierarchical approach to management of wastes is:

a) Waste avoidance / minimisation

b) Re-use and recycling (if it does not threaten public health safety and the environment).The biodegradable wastes are a good source for compost and biofuels. Resource recovery is also possible for non- biodegradable wastes if there are no constraints with regard to public health and the environment.

c) Treatment to destroy the hazardous components of the waste:

(i) Land treatment for biodegradable wastes

(ii) Incineration- This is a treatment technology involving destruction of hazardous component of waste by controlled burning at high temperatures. The resulting non- burnable ash and other residue must be removed and transported to a final disposal site. (

iii) Treatment of sewage- The treatment processes produce a liquid effluent and sewage sludge. The liquid effluent is discharged to natural waters subject to applicable standards and regulations. The sewage sludge can be used as a fertilizer on agricultural land (If it does not pose harm to health and the environment), otherwise it is incinerated.

d) Final disposal:

i) Engineered landfill - The open dumps create a nuisance by being unsightly, breeding pests, polluting the air, and polluting ground water and surface water. The engineered landfills (sanitary and secure) are designed to minimise the chance of release of leachate (hazardous liquid substances) into the environment.
(ii) Ocean dumping or disposal at sea (subject to public health and environmental considerations).
(iii) Deep-well disposal:- This entails disposing of waste by injection into deep wells, in the rock which is below and completely isolated from all fresh water aquifers, thereby circumventing contamination of water table. However, disposal of liquid waste in deep wells has been linked to increase in occurrences of earthquakes in seismically active areas.
(iv) Concentrate and contain -This is used for wastes that defy known treatment method.









“In a society where we think of so many things as disposable, where we expect to be constantly discarding last year's gadget and replacing it with this year's model, do we end up tempted to think of people and relationships as disposable? If we live in a context where we construct everything from computers to buildings to relationships on the assumption that they'll need to be replaced before long, what have we lost? God is involved in building to last. He doesn't give up on the material of human lives and He asks us to approach one another and our physical world with the same commitment. God doesn't do 'waste'.”
- Rowan Williams

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