Environmental Management in Practice Part 10 ppt

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Environmental Management in Practice Part 10 ppt

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Retrofit Approach for the Reduction of Water and Energy Consumptionin Pulp and Paper Production Processes 261 Fig. 11. Representation of the pulp production process after reduction of fresh water consumption. Environmental Management in Practice 262 No. Flowrate (ton/hr) Concentration (%) Mass Load (Kg) No. Flowrate (ton/hr) Concentration (%) Mass Load (Kg) 1 72.500 12 8700 14 767.140 0.009369 71.87 2 202.731 0.009369 18.99 15 71.208 12 8545 3 302.600 3 9078 16 596.167 0.009369 55.85 4 54.412 0.009369 5.566 17 170.973 0.009369 16.02 5 65.748 2.1 1380.7 18 33.199 1.5 498 6 296.264 2.6 7702.9 19 5.831 2.321 135.4 7 19.483 0.009369 1.825 20 27.369 1.325 362.634 8 33.199 1.5 498 21 27.369 1.325 362.634 9 52.032 1.7 884.54 22 27.369 1.325 359.007 10 348.296 2.466 8547.4 23 1.260 0.2878 3.626 11 314.541 0.009369 29.47 24 27.369 1.312 359.007 12 662.837 1.3 8616.9 25 1.260 0 0 13 175.512 0 0 Table 5. Process information for the stabilized process. On the start up of the plant, 760.56 ton/hr of fresh water are needed. Of these, 168.78 ton/hr are sent to the washing stage while the rest, 591.678 ton/hr are used for dilution purposes before entering filter 3. Once the regeneration processes enter into operation and the reuse of effluent 3 is established, the fresh water consumption is reduced to 176.772 ton/hr. From the ongoing discussion it can be seen that regeneration and reuse considerable reduce the fresh water consumption by reducing the need of using fresh water to feed the filter at a concentration of 1.2%, thus achieving a saving of 582.626 ton/hr. In the case under consideration there are various types of effluent stream with different contaminant concentrations, therefore it is important the adequate selection of the regeneration process for water reuse of recycling whatever the case. Regeneration processes are of the distributed type unlike the end of pipe treatment, which in the majority of cases is of centralized type. Fig. 12 shows the inlet and outlet process water flow rates. Fig. 12. Water effluent streams of the pulp production process. 4.2.3 Regeneration for water reuse Fig. 13 shows the application of a specific treatment to each of the effluent streams in the pulp production process. Appropriate selection of each of these treatments is critical since given the different contaminant composition. Retrofit Approach for the Reduction of Water and Energy Consumptionin Pulp and Paper Production Processes 263 The characteristic of the effluents of the cooking processes as given by Sumathi and Hung (2006) are: high oxygen demand (BOD), color, it may have sulfur and resin reduced compounds. The effluent of the washing process, on the other hand, contains large amounts of suspended solids (SS), BOD and color. The effluent from the bleaching process contains organochloride compounds, BOD and resin. Now, the level of regeneration can be total or partial. The main types of regeneration processes can be divided in to physical-chemical and biological. Amidst the physical-chemical are: membrane separation techniques (inverse osmosis, ultrafiltration, nanofiltration, etc.), chemical flotation and precipitation and advanced oxidation processes. The biological processes are: activated sludge, anaerobic treatment, sequential anaerobic-aerobic system and fungi system for color and organo- halogenated derivatives. It is important to emphasize that in the majority of cases 100% regeneration is not targeted; however, what is sought is the minimization of the fresh water consumption and the flow rate o the discharged effluent. In this part, no numerical results are presented since this is outside the scope of this work. Fig. 13. Distributed treatment system for the effluents from each of the stages of the pulp production process. 4.2.4 Heat recovery system The reduction of fresh water brings about important changes in the need of energy consumption since the pulp production process requires water streams at different temperatures. This stage of the analysis seeks to clearly identify the situations where energy is reduced as a result of a reduction in water consumption through the application of pinch analysis. Fig. 14 shows the case where water consumption is reduced after increasing the conversion in one of the reactors if the bleaching stage. If fresh water is available at 40ºC and it has to be heated up to 60 ºC before been fed to the filter as shown in Fig. 15, the amount of energy saved is 52.1 kW . So, in order to take the temperature from 20 ºC to 40 ºC, the water and energy saving is 10.391 ton/hr and 242.45 kW, respectively. Another type of sitations that arises is the one shown in Fig. 15, where stream 13 enters the process at 60 ºC and stream 12 reaches the filter at a temperature equal or larger than 35 ºC. After a water reuse scheme is applied, stream is reused 11 and since its temperature is above 35°C, an energy saving of 5,504 kW is achieved compared to the system where fresh water is used. Environmental Management in Practice 264 Fig. 14. Schematic of an energy saving application in the washing stage. Fig. 15. Schematic of an energy saving process application. In summary and putting together the results of the reviewed operations (washing and bleaching), the total amount of water saved is 582.626 ton/hr and an energy saving of 5504 kW is achieved. En el blanqueo se obtiene un ahorro de agua fresca de 11.511 ton/hr y un ahorro de energía de 294.55 kW. It is important to mention that water and energy savings have been achieved simultaneously by applying the methodology to particular unit operations. Retrofit Approach for the Reduction of Water and Energy Consumptionin Pulp and Paper Production Processes 265 5. Conclusions This chapter has introduced a genera approach for the retrofit of existing processes for the reduction of water and energy consumption. The methodology introduced is based on a conceptual structured scheme with different hierarchical levels arranged in the following way: Level 1. Analysis of the reaction system Level 2. Analysis of the water using network Level 3. Analysis and implementation of water regeneration schemes. Level 4. Analysis of the heat recovery system. This new approach direct us to determine the way changes to operating conditions affect the water and energy requirements in a process. In addition, these modifications can be viewed in the light of an economical analysis which shows the economical feasibility of the retrofit projects. 6. Acknowledgment Thanks to Haydee Morales Razo. This work was supported by SEP-PROMEP (México) through grant PROMEP/103.5/11/0140. 7. References Calloway, J., T. Retsina, et al. (1990). Pinch technology in practical kraft mill optimisation. Engineering Conference Proceedings. Linnhoff B. Townsend, D.W., Boland, D., Hewitt, D.F., Thomas, B.E.A., Guy, A.R. and Marsland RH. (1982)User Guide on Process Integration for the Efficient Use of Energy, Institution of Chemical Engineers. IchemE, Rugby-UK. Berglin, N., J. Strömberg, et al. (1997). Using process integration to approach the minimum impact pulp mill. Environmental Conference Proceedings. Rouzinou, S., T. Retsina, et al. (2003). Pinch analysis: A powerful tool for the integration of new process equiment into existing pulp and paper. Fall Technical Conference. Savulescu, L., B. Poulin, et al. (September 2005 c). "Water and energy savings at a kraft paperboard mill using process integration." Pulp & Paper Canada 106(9): 29 -31 Towers, M. (March 2005). "Energy reduction at a kraft mill: Examining the effects of process integration, benchmarking, and water reduction,." Tappi Journal 4 (3): 15 - 21. Wising, U., T. Berntsson, et al. (2005). "The potencial for energy savings when reducing the water consumption in a Kraft Pulp Mill." Applied Thermal Engineering 25: 1057 - 1066. Nordman, R. and T. Berntsson (2006). "Design of kraft pulp mill hot and warm water systems- A new method that maximizes excess heat." Applied Thermal Engineering 26: 363 - 373. Parthasarathy, G. and G. Krishnagopalan (2001). "Sistematic reallocation of aqueous resources using mass integration in a typical pulp mill." Advances in Enviromental Research 5 61 - 79. Lovelady, E. M., M. El-Halwagi, et al. (2007). "An integrated approach to the optimisation of water usage and discharge in pulp and paper plants." International Journal of Environment and Pollution 2007 29(No. 1/2/3): 274 - 307. Environmental Management in Practice 266 Savulescu L. E., A. Alva-Argáez, Direct heat transfer considerations for improving energy efficiency in pulp and paper Kraft mills, Energy, 33(10) (2008), 1562-1571. European Commission (2001). "BREF in the Pulp and Paper Industry". Westerberg A. W., H.P. Hutchinson, R.L. Motard y P. Winter (1979). "Process Flowsheeting", Cambridge Univ. Press, Cambridge, England. Shenoy U. V. (1995)."Heat Exchanger network Synthesis", Gulf Publishing Co. 1995 Douglas J. (1988), "Conceptual Design of Chemical Processes". Mc Graw-Hill Co. Walas S.M (1988) Chemical Process Equipment Selection and Design, Butterworths Gullichsen J., C.J. Fogelholm, Papermaking Science and Technology – Chemical Pulping, Fapet OY, Helsinki, 1999. Peters, M., Timmerhaus, K. 1991. Planta design and economics forchemical engineers. 4. ed. Mc.Graw Hill. Nueva York, NY. EEUU. R. Smith, Chemical Process Design and Integration, John Wiley & Sons Ltd., Chichester, 2005. Jacob, J., H. Kaipe, et al. (2002). "Water network analysis in pulp and paper processes by pinch and linear programming techniques." chemical Engineering Communications 189(2): 184 - 206. Koufos, D. and T. Retsina (2001). "Practical energy and water management through pinch analysis for the pulp and paper industry." Water Science Technology 43 (2): 327 - 332. Sumathi S., Yung-Tse Hung ,(2006). Treatment of Pulp and Paper Mill Wastes. Treatment in the Process Industries. (Editores: Wang, L.K., Hung Y., Lo H.H., Yapijakis, C.). Editado por Taylor and Francis. Pp 453-497. 13 An Application Model for Sustainability in the Construction Industry Fernando Beiriz and Assed Haddad Federal Fluminense University and Federal University of Rio de Janeiro Brazil 1. Introduction Over the years, mankind’s development of a large industrial capacity and its ability to create new technologies that turn easier society’s daily life has been a mark of innovation era. In many developing industries, technologies are incorporated into daily life by becoming indispensable to the modern lifestyle. Waste production has been increasingly alarming throughout the world, standing as a major problem to be solved.In order to achieve life quality and be able to provide favorable environmental conditions to future generations, it is indispensable to become conscious about environmental effects of all mankind’s production activities. It is vital to promote and encourage an environmental sustainability culture development: meeting society’s demand of industrial and technological products with the indispensable proper disposal of their products at the end of life, that is, discard minimizing environmental impacts on the completion of its life cycle. Some measures have been taken over recent years, with the intention of minimizing the generation of environmentally hazardous waste in the world, emphasizing the relevance of changes in production processes. In the specific case of construction, begins to be aroused interest from external factors. Among them, there is the availability of solutions to minimize negative environmental impacts identified and applicable management tools. Methods for evaluating environmental performance of the construction industry and increased competition in the industry and customer requirements are also seen as elements boosters, which come to be added to increase environmental awareness at the part of builders. Similarly, as many construction companies have implemented quality management systems that have brought them considerable benefits, it increases their interest in introducing environmental elements into existing systems. However, there are few builders that are committed to environmental issues. Still, environmental solutions have begun to be applied in enterprises, although this does not ensure continuous improvement and sustainable development of the sector. Despite its recognized economic impacts to the country such as: high job creation, income and viability of housing, infrastructure, roads and others; in the construction sector one still lacks a firm policy for disposal of solid waste, mainly in urban centers. The need to take the RCC not only results in a desire to economize. This is a fundamental attitude towards the preservation of our environment. Environmental Management in Practice 268 The important thing to be improved in this sector is the management process, with the decrease in solid waste generation and appropriate management of the same construction site, building awareness of the actors involved, creating the methodology. It is noteworthy that is necessary a change of culture among all those involved in the process of IC, indicating the importance of preserving the environment we live. Therefore, it is notorious the necessity of a mentality change in the aspect of environmental sustainability at the IC sector’s stakeholders, in order to fortify and develop a responsible conduct, aware of the relevance of preserving and extracting as better as possible the environment’s resources. 2. Construction industry sustainability The term sustainable development can be seen as a key word this time. As there are numerous definitions for this term, the two most common definitions known, cited and accepted are the Brundtland Report (WCED, 1987) and the document known as Agenda 21. The best known definition of the Brundtland Report, presents the question of future generations and its possibilities. It contains two key concepts: the necessity and the idea of limitation. The first refers particularly to the needs of developing countries and, second, the idea imposed by the state of technology and social organization to meet the needs of present and future. The question of emphasis on the social component of sustainable development is reflected in the debate taking place about the inclusion or not of social measures in the definition. This discussion appears in the variety of ideas about sustainability that contains components that are not usually measured, such as cultural and historical. Social indicators are considered particularly controversial, since they reflect political contexts and value judgments. The integration of mitigation measures is further complicated because of different and often conflicting dimensions. The definition of the Brundtland Report does not provide a static state, a more dynamic process that can continue to exist without self-defeating logic prevailing. The different forces acting on the system must be in balance for the system as a whole is maintained over time. According to Pearce (1993), there are different environmental ideologies that make environmentalism a complex and dynamic phenomenon. Inside of environmentalism, the author identifies two ideological extremes: on one hand the technocentrism, and the other the “ecocentrism”. Within this continuum one can identify four fields, with particular characteristic. Pearce uses four classifications: sustainability very weak (very weak sustentability), weak sustainability (weak sustentability), strong sustainability (strong sustentability) and sustainability very strong (very strong sustentability). You can also find a parallel Naess (1966) makes between Deep Ecology (deep ecology) and ecology superficial (shallow ecology). In ecology the central objective is superficial affluence and health, along with the fight against pollution and resource depletion. Focus on deep ecology focuses on biospheric egalitarianism and the principles of diversity, complexity and autonomy. Authors linked the trend technocentric believe that sustainability refers to the maintenance of total capital available on the planet and that it can be achieved by substituting natural capital for capital created by human ingenuity. In extreme ecocentric the authors emphasize An Application Model for Sustainability in the Construction Industry 269 the importance of natural capital and the need to preserve it, I value not only for financial but mainly for its substantive value. Ecological sustainability means to expand the capacity of the planet by using the potential found in diverse ecosystems, while the continuing deterioration in a minimum level. It should reduce fossil fuel use and emission of pollutants, but also adopt policies for the conservation of energy and resources to replace. The geographical sustainability can be achieved through a better distribution of human settlements and economic activities. It must seek a rural-urban setting most appropriate to protect biological diversity, while it improves the quality of life. Finally, cultural sustainability, the most difficult to bring the second SACHS (1997), is related to the path of modernization without the disruption of cultural identity within specific spatial contexts. To SACHS (1997), the concept of sustainable development refers to a conception of the limits and the recognition of the weaknesses of the planet; focuses on both the socioeconomic problem and satisfying the basic needs of populations. Although the starting point of the various approaches is different, there is a recognition that there is a space of interconnection or overlap between these different dimensions. Achieve progress toward sustainability is clearly a choice of society, organizations, communities and individuals. How covers different choices, change is only possible if there is greater involvement of society. In short, sustainable development requires the society to think in terms of long-term and recognize its place within the biosphere. The concept provides a new perspective of observing the world, which has proven to be the current state of human activity inadequate to meet existing needs, and seriously threaten the prospect of future generations. The goals of sustainable development challenge contemporary institutions. They have governed global changes reluctant to recognize that this process is actually occurring. The differences in the concept of sustainable development are so great that there is no consensus on how to measure sustainability. Unfortunately, for most authors cited earlier, does not have an operational definition of minimally acceptable. All definitions and tools related to sustainability must consider the fact that no one knows fully how the system operates; one can only discover environmental impacts of activities and interaction as human welfare, the economy and the environment. In general, it is known that the system interacts between different dimensions, but do not know specifically the impact of these interactions. All aspects presented show the diversity and complexity of the term sustainable development. 3. Reverse logistics and waste management The high competition among companies and constant increase in efficiency in the management processes of production, has characterized the current business environment. Among the many processes present in a company, there is the logistics business, which is geared to ensure the delivery of the product produced correctly in the right place at the moment and want the lowest possible cost. In many industries, logistics has received more attention, mainly due to the globalization of markets and consumer pressure to reduce distribution costs. The client, in turn, is embedded in consumer culture, which is driven by the cycle "buy-use- disposal", demonstrating that culture is unsustainable and inadequate to perishable Environmental Management in Practice 270 perpetuation of current conditions for survival in contemporary society, because it stimulates the increasing manufacture of new products to the detriment of reuse and recycling of byproducts or waste. Thus it is observed that actions to boost consumption are not planned with a systemic view, since their products are not useless options, structured reuse, leaving only the landfilling as a solution to dispose of them. In this scenario, reverse logistics, or more precisely the deployment of reverse logistics gains importance in the supply chain. The structure of the reverse channel is a way to make new use of these products, through a new job or a transformation of industrial processing, in other useful products. Thus, reverse logistics has a great interface with sustainable development, since the mobilization of the chains allows the reuse of reverse obsolete products, byproducts and waste, reducing the volume of discarded into the environment and the extraction of new resources. It also presents another favorable feature, since the emergence of new business also promotes the social, financial returns and allows companies involved in chains reverses. Particularly in the construction industry, reverse logistics systems are designed to develop reverse chain for reuse of products and waste generated in production processes and establish the agents working in it, the census of responsibility throughout the product life cycle. This attitude is shared not only by builders but, especially, by supplying materials for these are in an industrial environment, where there is less variability of the process. Thus, these companies can become drivers of implementation of this concept throughout the production chain construction. In the construction sector, it is assumed that interest is still incipient and demonstrated by a few industries, as are the Brazilian initiatives for the reuse of industrial waste. Applying the concept of reverse logistics in IC may occur in several ways. It can form themselves into organizational tool for the flow of aftermarket products, post-consumer waste from the production process of mobilization and demobilization of equipment used during construction of the project, and set yourself up as a new initiative or as an enhancement of existing reverse channel. Specifically, with regard to flows, the amount and variability of waste composition of the construction industry generate flows of very different characteristics. IC flows in post-consumption and production (waste) are hardly distinguished, because they occur simultaneously, except when the demolition of a building, a notoriously product stream after consumption. Flows of products after sale are mainly for returns sent by mail-order and are usually intended for the secondary market, which, for example, donated to charity. Still others come from equipment and transportation as the return and withdrawal of lifts and cranes. The biggest concern now rests on the post-consumer products or processes, generally named construction waste. Applying the concept of reverse logistics in IC may also have coverage from a company in isolation, this and its supply chain, as well as sectored organization, or the entire production chain (the reverse supply chain). When the reverse logistics systems of IC are shared by all actors in the chain and these are strategic objectives aligned on the reuse of reverse flow, consolidates the management of reverse supply chain (reverse supply chain management). [...]... techniques are used having in mind preservation of these segregated materials for its future use or the use of the land itself throughout application of some engineering principles to confine them The Construction Industry Waste Management Integrated Plan (Plano Integrado de Gerenciamento de Resíduos da Construção Civil) structured as shown above 272 Environmental Management in Practice Construction... terminals for oil and gas, chemicals products and mining;  Aeroports;  All types of pipelines including sewage, oil, gas, mining and others;  Power lines, beyond 230KV;  Water resources facilities including Hydro Plants beyond 10MW, irrigation works, sewers, navigation channels, etc;  Fossil fuels extraction;  Mining extraction;  Sanitary landfills, toxic or hazardous;  Power Plants generating... generators;  Mapping of public or private areas, suitable for receiving, segregation a temporary storage of small waste volumes, according to urban municipal zoning This allows further destination for waste management plants or recycling;  Establishment of licensing procedures for areas of processing and final waste destination;  Determination of prohibition of disposal in non licensed areas;  Incentives... - EIA/RIMA) are only mandatory in special cases 4.1 The waste management program This waste management program aims at the reduction of waste production and correct destination of what remains in activities involving in construction, retrofitting, remodeling, maintenance and demolition in all types of construction related activities and subsectors of the Construction Industry Table 1 shows Brazilian... than 10MW;  Industrial and agricultural units and complexes;  Industrial districts and strictly industrial zones;  Wood exploration in large areas or in some subject to special environmental interest;  Urban Projects in large areas or in some subject to special environmental interest;  Any activity use coal from vegetal sources in excess to ten tons a day  Canals and Harbour structures The Environmental. .. implementation and operation of recycling plants;  Minimum and maximum indices of recycled content in certain products;  The environmental certification of products An Application Model for Sustainability in the Construction Industry 283 Trade unions should organize their members assisting in the dissemination studies and awareness of environmental responsibility and sustainable construction The academy... Global EPCM (Engineering, Procurement and Construction Management) Enterprise, RMIT University, Australia Couto A & Couto, J P (2 010) Guidelines to Improve Construction and Demolition Waste Management in Portugal, Process Management, pp 285-208, Intech, ISBN 978-953307-085-8, University of Minho, Portugal Rutherford, I (1997) Use of models to link indicators of sustainable development In: MOLDAN, B;... firms in Asia that had already received ISO 14001 certification and adopted these Environmental Management Systems (EMS) standards as their state policy No doubt that many firms have recognized the compatibility between environmental performance and profitability, as it witnessed by increasing interest in recycling programs and green marketing, in part due to realizing that the futility of running from... Second, it is defined by its capital volume that is less than 80 million Taiwan dollars The SMEs are typically much smaller in operation compared to the global and multinational enterprises, whereas most of the SEMs in Taiwan are positioned in the ending-role of the supply chain Most EMSs in Taiwanese SMEs are implemented in 286 Environmental Management in Practice accordance to specification in ISO 14001... Manoliadis, O G (2007) The Role of Adaptive Environmental Management in Sustainable Development Case Study Assessing the Economical Benefits of Sustainable Construction in Greece, Environmental Technologies: New Developments, E B Ö Güngör (Ed.), pp 85-96, InTech, ISBN 978-3-902613 -10- 3, Democritus University of Thrace, Greece Chan, H K., (2 010) A Process Re-engineering Framework for Reverse Logistics based . innovation era. In many developing industries, technologies are incorporated into daily life by becoming indispensable to the modern lifestyle. Waste production has been increasingly alarming. and mining;  Aeroports;  All types of pipelines including sewage, oil, gas, mining and others;  Power lines, beyond 230KV;  Water resources facilities including Hydro Plants beyond 10MW,. This waste management program aims at the reduction of waste production and correct destination of what remains in activities involving in construction, retrofitting, remodeling, maintenance

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