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Question: please help with question 3 i am posting this question...

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Please help with Question 3, I am posting this question 4 times

Question 1. Two types of grocery bags, plastic and paper, are available for consumers in supermarkets. Many studies have been conducted to compare the two products based on life cycle assessment. For paper bags, the life cycle includes steps of timber harvesting, pulping, paper making, product use and waste disposal. For polyethylene (PE) bags, the life cycle includes petroleum extraction, ethylene manufacture, ethylene polymerization, polymer processing, product use and waste disposal. A life cycle audit identified waste and emission inventories of paper and PE grocery bags as shown in Table 1. Although both types of bags are designed to have a capacity of 1/6 barrel, fewer groceries are generally placed in PE bags than in paper bags, with reported values ranging from 1.2 to 3. In this problem, it is assumed that 2 PE grocery bags are required to replace a paper grocery bag 1) Using the data in Table 1, determine the energy required (MMBtu) and the quantity of air pollutants released (Ib) per 1000 lb of PE bags produced. Also, determine the energy required and the quantity of air pollutants released for the quantity of paper bags capable of carrying the same volume of groceries as the 1000 lb of PE bags Both the air emissions and the energy requirements are functions of the recycle rate. So, perform means half of the bags are disposed of and the other half recycled after the product use stage of your calculations at three recycle rates: 0%, 50% and 100% recycled. Note that a 50% recycle rate their life cycle. PE bags have a mass of 0.2633 oz each; paper bags have a mass of 2.144 oz each. 2) Compare the energy requirements and air emissions of the paper bags with those of the PE bags 3) Table 2 indicates the characteristics of the air emissions due to both types of bags. Briefly discuss at different recycle rates the significant differences in atmospheric emissions for paper vs. PE grocery bags 4) The material and energy requirements of the PE bags are primarily satisfied using petroleum, a non-renewable resource. In contrast, the paper bags rely on petroleum only to a limited extent and only for generating a small fraction of the manufacturing energy requirements. Most of the energy requirements of pulp and paper manufacturing are met by burning wood waste Compare the amount of petroleum required for the manufacture of two PE bags to the amount of petroleum necessary to provide 10% of the energy required in the manufacture of one paper bag Assume 0% recycle, and that it needs 1.2 lb of petroleum to manufacture 1 lb of polyethylene The higher heating value (HHV) of petroleum is 20,000 Btu/lb Table 1. Air emissions and energy requirement for polyethylene and Life cycle stages Air emissions, oz/ba Pa Btu/ba PE 464 Ener PE 0.0146 Materials manufacture, product 0.0516 manufacture and product use 905 Raw material acquisition and 0.0510 0.0045 724 185 duct dis 1Franklin Associates Ltd. 1990. Resource and environmental profile analysis of polyethylene and unbleached paper grocery sacks: final report for The Council for Solid Waste SolutionsTable 2. Profile of atmospheric emissions for paper and plastic grocery bags Atmospheric emissions lb per 10,000 ba Paper ba Pollutant category Polvethylene ba 100% 100% Particulates Nitrogen oxides Hydrocarbons Sulfur oxides Carbon monoxide Aldehydes Other organics Odorous sulfur 0.8 2.1 5.8 2.6 0.7 0 0.8 1.7 3.2 2.7 0.6 0 24.6 9.2 4.9 13.6 7.0 0.1 0.3 4.5 0 2.8 8.0 3.9 10.6 6.5 0.2 0 0 0 0 Lead

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