Solid Waste Management 2018/12/1

Outline Introduction Refuse Disposal/collection in Buildings Transfer Station Solid Waste Disposal Methods Sanitary Landfills Legislation of Waste Control/Management Solid Waste Management Strategy in Hong Kong Construction & Environment Environmental Management System Appendix 1 – Wastes Appendix 2 – What have we done ? 2018/12/1

Introduction Classification of Solid Wastes Composition of Wastes in Hong Kong Recycle, Recover, and other pretreatment processes Summary of Waste Disposal Methods What are the problems we are facing on solid waste disposal ? 2018/12/1

Classification of Solid Wastes Domestic wastes Commercial wastes Industrial wastes including food-processing residue, ash, plastic, package wastes, etc. Construction wastes Hospital wastes Bulky waste including trees, furniture, telephone poles, etc. Hazardous wastes comprising of explosives, radioactive materials, toxic material, etc. Others : marine mud, sludge, livestock, abattoir, PFA, etc. 2018/12/1

Methods of Waste Disposal Domestic Wastes – by landfill, incineration, recycling Construction wastes – by public dump, recycle, landfill, Dredged & Excavated spoil – by marine dumping, public dumping Etc……. 2018/12/1

What are the problems with solid wastes ? 2018/12/1

What are the major solid wastes in HK ? Construction & Demolition Domestics Industrial Commercial Special 2018/12/1

How Construction Wastes are disposed of ? Reclamation (public dump) By landfills Moving towards more dumping dump Not much reuse 2018/12/1

What are the major composition of Domestic Wastes ? Putrescibles Papers Plastics Others Textiles, metals, Glass, Bulky wastes 2018/12/1

What are the major composition of Industrial & Commercial Wastes ? Papers Plastics Rattan/Wood Putrescibles Others Metals, glass, bulky wastes 2018/12/1

Disposal of chemical wastes Chemical wastes disposed at Chemical wastes Treatment centre at Tsing Yi, Others by landfills 2018/12/1

What conclusion can you draw ? Disposal is mainly one-way result in resource scarcity at one end and disposal problems at the other. Papers, Construction wastes, glass, etc. are valuable wastes that can be recycled, reused, recover Government should promote to use less and produce less wastes A lot of wastes are disposed of by landfill that requires a lot of land Landfill also creates environmental problems such as groundwater, air and noise pollution, explosion, traffic, disease, etc. 2018/12/1

What else can we do ? 2018/12/1

Use of Pre-treatment process (see figure) Grinding Pulverizing Sorting Separating Compacting Reuse, Recycle Disposed of by landfill, incineration, Generate power 2018/12/1

Waste Recover in HK Papers, Metals Glass Rubber tyres 2018/12/1

What other countries are doing ? Recycling and resource recovery in Japan – well organised and successful Use of other methods such as composting, pyrolysis, Anaerobic digestion 2018/12/1

Solid Waste Disposal Path 2018/12/1

Solid Waste Disposal Path Waste Collection Waste Reception & Transfer Waste disposal 2018/12/1

Waste Collection in Building Refuse chute Pneumatic system On-site incineration 2018/12/1

What are the pros and cons of the following Waste Collection methods ? Refuse chute Pneumatic system On-site incineration 2018/12/1

Waste Reception & Transfer Refuse transfer stations Refuse collection points Barge loading areas Waste handling facilities 2018/12/1

Solid Disposal Methods Open dumping Sanitary landfill Incineration Composting Pyrolysis High-temperature Size reduction (shredding, grinding pulverizing) 2018/12/1

Transfer Station 2018/12/1

What are the functions of a transfer station ? Compaction Size reduction by grinding, shredding, pulverising Material recovery Loading for transportation 2018/12/1

What are the considerations of a transfer station ? Haul distance to the disposal site 2018/12/1

Transfer Station in HK 1992 – Island East 1994 - Sha Tin 1997 – Island west, Kowloon west 1998 - outlying islands 2000 - NWNT 2005 - NNT 2018/12/1

Solid Waste Disposal Methods Open dumping Sanitary landfill Incineration Composting Pyrolysis High-temperature Size reduction 2018/12/1

Sanitary Landfill 2018/12/1

Pros of Sanitary Landfill Process is sanitary Highly skilled personnel not required After restoration, landfill site can become recreational land Natural resource returned to land 2018/12/1

Cons of Sanitary Landfill Large area is required Transportation cost Produce hazardous gas Ground and Surface Water contamination 2018/12/1

Selection of Landfill site Economic Socioeconomic Environmental/Geotechnical 2018/12/1

Process of Landfill Trench method – trucks dump the wastes into trench and a bulldozer spreads & compacts, and covers them at the end of day Area method – bulldozers spread out the waste and a scraper hauls the cover materials Ramp method – the wastes are compacted but the cover is excavated directly in front of the working face 2018/12/1

What are the problems with landfill ? Groundwater contamination by leachate Gas generation 2018/12/1

What is leachate ? Leachate is a liquid produced from a landfill that contains dissolved, suspended and/or microbial contaminants from solid wastes 2018/12/1

How leachate can be contained ? Provide soil cover and surface drainage to prevent infiltration of rain Liners to contain or attenuate the leachates Use under drains (single or double) to collect the leachate for further treatment Use slurry cut off wall/trench to contain the leachate To select a site in arid area To select a site above ground water To continuously monitor groundwater quality in the vicinity of the site 2018/12/1

What typical gases are generated from landfill ? CH4 CO H2S N2 NH4 H2 … 2018/12/1

How Gas Generation is controlled ? Passive Venting – the local geology allows the migration of gas to be collected by perimeter trench Active Venting – install gas extraction vent which is connected to a vacuum or blower to force the gas for collection 2018/12/1

What Constitute a good landfill ? Provide Extensive protection on Aesthetics measures regarding health and safety and quality of life of neighbours or pass by Ground water protection Surface water protection Control of landfill gas On site health & safety 2018/12/1

Aesthetics Provide slope berm and vegetation along the perimeter of the site Provide dust screen Prevent wind-blown dust Prevent erosion and animals Do not allow ponding of water Compact and cover waste daily 2018/12/1

Groundwater protection Provide liner Provide leachate collection system No groundwater around site Provide ground water monitoring 2018/12/1

Surface water protection Choose site in arid (dry) area Provide surface drainage to divert surface runoff No ponding of water on site 2018/12/1

Control of landfill gas Provide fully lined landfill Provide active venting system Choose site away from people Monitor gas around site 2018/12/1

Confine in-coming waste to one working area On site health & safety Cover soil daily Confine in-coming waste to one working area Provide safety training and safety procedures 2018/12/1

Solid waste disposal Open dumping Sanitary landfill Incineration Composting Pyrolysis High-temperature Size reduction 2018/12/1

What is incineration ? 2018/12/1

What are the pros and cons of incineration ? 2018/12/1

What is composting ? 2018/12/1

What is pyrolysis ? 2018/12/1

What is high temperature Incineration ? 2018/12/1

Comparing the cost of incineration and landfill 2018/12/1

Legislation for Waste Management 2018/12/1

What are the legislation for Waste Management Waste Disposal Ordinance, 1980- responsible for licensing of all types of wastes Regulations for livestock wastes in 1987. Regulations for chemical waste disposal, 1992. 2018/12/1

What are the industries and community facilities that require special requirements for waste disposal ? Industries e.g. Electricity, gas generation Metal finishing Printed circuit board, Tannery processing ..etc Community facilities e.g. abattoirs Hospitals Markets, cooked food stalls 2018/12/1

Government structure Policy Development – Environmental Protection Department Service Provision – Refuse collection (FEH); Special Waste collection (EPD); Solid Waste disposal (EPD); Special waste disposal (EPD); Sewage treatment (DSD) Legislation enforcement – Waste import/export (EPD); Livestock waste (EPD); Marine dumping (EPD); Domestic waste storing, collection, littering (FEH); 2018/12/1

Solid Waste Management in HK 2018/12/1

Waste Management in HK Municpal disposal by - 3 large landfills, 9 planned transfer stations Construction wastes disposal by - public dump for reclamation after segregation, sorting and recycling. Also adopt Polluters Pay Principle 30% clinical waste by incineration and 70% by landfill Marine mud by controlled dumping at specified seabed Waste reduction Plan by Waste minimisation by changes in people’s practice Waste recovery and recycling Reduce the volume of waste Disposal in environmentally satisfactory ways 2018/12/1

Environment & Construction 2018/12/1

Impact of Construction Cause changes to ecosystem Loss of forest Loss of cultivated land Air, noise, groundwater, ozone pollution Continuous reclamation Extraction of fossil fuel and minerals Consumption of resources Construction activities 2018/12/1

Measures to reduce Impact to Environment Reuse of building materials – e.g. use brick on pavement surface instead of concrete Recycle of materials – e.g. Use crushed concrete for roadbase Reduce energy consumption – e.g. use less energy means less electricity means less wastes from electric company Design & build energy efficient buildings Promotion by education programme Conduct EIA and EMS 2018/12/1

Environmental Management System 2018/12/1

What is a EMS EMS is a systematic approach for implementing environment management particularly at organisation level. Through identifying, minimising, preventing and managing the environment impacts 2018/12/1

What does EMS consist ? 1. Environmental policy 2. Organisation Structure 3. Environmental Management Programme 4. Audit of the programme & system 2018/12/1

Why EMS ? Comply with legislation Demand from customers Competition Save cost Reduce risk Investment approval Pressure from environmentalists 2018/12/1

What is ISO14000 ? A series of standards on environmental management ISO14001 set out the framework in management system for tracking environmental performance, setting objectives, developing procedures, and reviewing progress. 2018/12/1

END 2018/12/1