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PHYSICAL, CHEMICAL, AND BIOLOGICAL PROPERTIES OF MUNICIPAL SOLID WASTE
1. Make sure that you remember the following words and expressions: battery; mayhem, cause/create/wreak ~; manslaughter, to admit/deny ~; negligence, criminal negligence, to sue (sb) for negligence; mercy (syn. euthanasia); maim, disfigurement, disfigured, disfiguring; statutory rape; subservient, subservient to, subservient role/position; embezzle, embezzler, embezzlement; forgery, to counterfeit, to counterfeit currency/money/goods/software, accessory after the fact; a fence 2. Match the words in Column A with their definitions in Column B. Make up your own sentences with these words.
3. Match the words in Column A with the words in Column  to make up possible word combinations.
4. Choose the word that best completes the sentence and insert it in the correct form:
1. Linked to the Mafia he was also behind _________ currency scams and drug_________. 5. Insert prepositions where necessary: 1. Most doctors are opposed ____euthanasia ____ethical grounds. 2. They admitted ___ counterfeiting documents. 3. The United Nations estimates that 800 people are killed ____ mines every month, and another 1,200 are maimed. 4. On two separate but very well publicized occasions Errol Flynn was accused _____ statutory rape. 5. Those arrested Wednesday face ____ criminal charges ____ forgery and falsifying business records, both ____ which carry possible jail sentences. 6. Canseco was charged _____ simple battery and was scheduled for a bond hearing Thursday.
PHYSICAL, CHEMICAL, AND BIOLOGICAL PROPERTIES OF MUNICIPAL SOLID WASTE Unit 4 Task 1. In pairs answer the following questions: 1. Why do you think it is important to know physical, chemical, and biological properties of MSW? 2. What physical, chemical, and biological properties of MSW do you know?
Task 2. Pay attention to the correct pronunciation of the following words.
Task 3. Learn new words and phrases.
Task 4. Translate the following words and phrases.
Task 5. Make up your own sentences using words and phrases from the tasks 2, 3, 4. Task 6. Skim the text and tell what the general idea of the text is.
PHYSICAL, CHEMICAL, AND BIOLOGICAL PROPERTIES OF MUNICIPAL SOLID WASTE The purpose of this chapter is to introduce the reader to the physical, chemical, and biological properties of municipal solid wastes and to the transformations that can affect the form and composition of MSW. These properties must be known to develop and design integrated solid waste management systems. PHYSICAL PROPERTIES Important physical characteristics of MSW include specific weight, moisture content, particle size and size distribution, field capacity, and compacted waste porosity. Note, that the fundamentals of analysis presented in this chapter are applicable to all types of solid wastes. Specific Weight Specific weight is defined as the weight of a material per unit volume (e.g., lb/ft3, lb/yd3). Because the specific weight of MSW is often reported as loose, as found in containers, uncompacted, compacted, and the like, the basis used for the reported values should always be noted. Specific weight data are often needed to assess the total mass and volume of waste that must be managed. Unfortunately, there is little or no uniformity in the way solid waste specific weights have been reported in the literature. Frequently, no distinction has been made between uncompacted or compacted specific weights. Because the specific weights of solid wastes vary markedly with geographic location, season of the year, and length of time in storage, great care should be used in selecting typical values. Municipal solid wastes as delivered in compaction vehicles have been found to vary from 300 to 700 Ib/yd3; a typical value is about 500 Ib/yd3. Moisture Content The moisture content of solid wastes usually is expressed in one of two ways. In the wet-weight method of measurement, the moisture in a sample is expressed as a percentage of the wet weight of the material; in the dry-weight method, it is expressed as a percentage of the dry weight of the material. The wet-weight method is used most commonly in the field of solid waste management. Particle size and size distribution The size and size distribution of the component materials in solid wastes are an important consideration in the recovery of materials, especially with mechanical means such as trammel screens and magnetic separator Field Capacity The field capacity of solid waste is the total amount of moisture that can be retained in a waste, sample subject to the downward pull of gravity. The field capacity of waste materials is of critical importance in determining the formation of leachate in landfills. Water in excess of the field capacity will be released as leachate. The field capacity varies with the degree of applied pressure and the state of decomposition of the waste. A field capacity of 30 percent by volume corresponds to 30 in/100 in. The field capacity of uncompacted commingled wastes from residential and commercial sources is in the range of 50 to 60 percent. Permeability of Compacted Waste The hydraulic conductivity of compacted wastes is an important physical property that, to a large extent, governs the movement of liquids and gases in a landfill. Date: 2014-12-28; view: 3122
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