The Use of LCA in Waste Management
Life Cycle Assessment is a process that is objective, and which is used to evaluate the ecological burdens correlated with an action, products or process, through quantification and identification of materials and energies used as waste. As Barton (1996, pp. 40) puts it, LCA implements and assesses alternatives to permit ecological improvements. Moreover, LCA is used to evaluate ecological burdens that are correlated with products or processes, which are involved in a Cradle to grave manner. That is, from manufacture of raw substances to eventual waste disposal. LCA accounts aspects that are not dealt with by other tools of ecological management, such as, evaluation of statutory consequences. In addition, LCA is used as an ecological tool of evaluating options for disposing waste. The hierarchy of managing solid waste is usually validated by life cycle analysis.
The aim of sustainable waste management is to handle the societys waste in a manner that is environmentally efficient, socially acceptable and economically affordable. To evaluate such sustainability, tools are required that can predict the probable entire environmental burdens of a given waste management system. Life cycle assessment (LCA) can be used in waste management systems to evaluate their entire environmental burdens. The aspect of integrated waste management combines waste collections, waste rivers, and treatment and disposal techniques with the aim of attaining environmental gains, societal acceptability and economic optimization. Tools of life cycle assessment can be applied to integrated waste management to prop up the development of sophisticated sustainable systems of waste management.
Generally, life cycle assessment practitioners usually focus on the techniques and the aspects associated with product life cycle development. Today, there is significant interest in the application of life cycle assessment to entire waste management systems and not on a particular waste management process applied in treating a single product. The outcome of this area of research has brought about the optimization of the entire waste management systems which are responsible for treating municipal solid waste (Finnveden et al, pp. 190).
The Various Considerations in Assessing the Environmental Impacts of Waste Disposal
In order to learn this topic, As Ekvall1 and Finnveden (2000, pp. 27) explain, a number of life cycle assessments have been carried out while focussing on the correlations between burning and reprocessing, as well as energy recovery. A number of studies have resulted to a variety of conclusions because of the discrepancies in the methodologies and hypotheses that were made in the analysis of the LCI (life cycle inventory). Main factors in the results of life cycle inventory would encompass the amount of energy replaced by the burnt waste paper the material that is surrogated by fibres that have been recycled the usage of pulpwood savings the external energy haulier that was applied in the process of recycling and the ecological encumbers that are correlated with the alteration in the demand of electricity. Various decision milieus as well as a variety of geographical, time, and moral perceptions can be used to investigate these factors. Moreover, different perceptions and time will require different alternatives. Thus, for one to get a conclusion that is sufficient, heshe needs to specify the correlation in terms of the relevant perceptions.
Nowadays, the methodologies used in LCA are being applied by several nations to assess sundry policies an incorporated management of solid waste together with treatment alternatives for fractions of particular wastes. The ongoing controversy is on the ecological aspects of a number of options for managing wastes. Waste managements, like incineration and recycling may lead to ecological gain. Although, recycling of material can minimize the ecological burdens that are correlated with an alternative way of producing energy. Consequently, recovery of energy can as well minimize ecological burdens that are correlated with options for producing energy. The approach of LCA, which is usually systematic and broad, makes it probable to assess the ecological burdens and gains of different alternatives, like Incineration, Recycling, Composting, and Land Fill (Al-Humoud, 2002, pp. 407).
Recycling vs. Incineration
The process of recycling process is encompassed within the confines of the system of managing wastes. The ecological burden that is correlated with the re-processing of every waste fraction recovered while accounting the following processes the consequences of transporting recovered material and possibility of saving consumption of energy. The amount of material replaced per ton of the product that has been recycled is dependent on the quality as well as varies with every material that has been recovered, and which is going to be reprocessed. The total energy that is used in recycling is lower than in incineration, with recovery of heat given that the content of energy is encompassed in the balance.
For instance, less energy is required in waste paper recycling, while paper production and virgin pulp requires more energy. Moreover, the usage of biomass, for energy, and for paper, is lower with regard to recycling than in incineration, with recovery of heat. Thus, recycling saves biomass, which can be applied for other purposes in the universe. For each management option, the additional activities required may be required will encompass to carry out the ecological correlation between recovery of material, and energy in different perceptions appropriately choose the method of managing waste choosing between other renewable ways of producing energy, or investing in firms that deal with waste incineration and making decision basing on ecological correlation between recovery of material and energy.
Correlations ought to base on ethical views regarding what makes a good action. A probable perception could be to assess every action basing on the impacts of that action (Finnveden et al, pp. 193).
Composting
Composting encompasses a net energy consumption to produce a substance that will be used as a fertilizer. Energy consumed during the process of composting is 54MJton, of inputs to the process of composting, and the diesel consumption in strainers, wheel loaders, and mills is 555.5 MJton of inputs to the process of composting. The unprocessed material, which is obtained during the process of composting, can be used as a fertilizer. The material that has been avoided is a chemical fertilizer that contains amount of nutrients that are equivalent to N and P. As Finnveden et al (1995, pp. 190) observe, the compost has a nutrient content of 2.0 kg of P and 8.3 kg of N per ton of inputs to the process of composting. Basing on assumption, the replacement of unprocessed fertilizer in the model and with regard to the contents of P and N is 100 percent. This shows that emissions that are evaded by use of compost in place of chemical fertilizer are accredited to the system of managing waste Idemat is used to obtain the LCI (life cycle inventory) P and N chemical fertilizer that is usually avoided (Ozeler et al, 2006, pp. 329).
Land Fill
Waste streams that can be sent to the landfill depending on the circumstances can be categorized into three Residual substance from the processes of composting Residual restwasteswastes, which are gathered, and land filled directly and Using processes of sorting to sort residues at MRFs. The process of land filling normally consumes energy in form of diesel while in disposal operations. As Finnveden et al (1995, pp. 193) puts it, solid wastes that directly arrive at the landfill consume fuel of 6.72 MJton of waste disposed. The impacts from generation of leachate and land fill gas have been deemed for every fraction of waste. Production of land fill gas is mainly from waste fractions that are biodegradable. About 250m3N Biogas is formed per ton of unprocessed wastes that is biodegradable, such as textile, putrescible, and paper. On the other hand, approximately 100 m3N land filled residues per ton is formed from the process of composting. A calorific value (of 19.5 MJ per m3), is assumed.
Presently, much of the solid wastes (with exception of paper wastes), are being land filled. With time Land Fill will replace paper recycling in the incinerators, but this is dependent on the choice of the consumer. The waste, which is surrogated by an incinerated paper, is likely to end-up in land fills, where eventually, it will be decomposed. This will result to emissions of poisonous gases, such as methane (34). To that effect, this ought to be accounted in the ecological correlation, if the ethical view is that environmentally, actions that are deemed to be good are those with good ecological consequences.
Why Waste Managers and Local Authorities are Increasingly Using LCA for Deciding the Best Option for Waste Disposal
LCA is being increasingly used by managers as well as local authorities because with LCA, the best choice, which has the best ecological impacts, can be easily identified for the evaluations (Finnveden et al, 1995, pp. 197). The best option is the one that has least contribution to ecologically systems that are poor, and which are reliable to ethical views that every activity ought to be evaluated basing on whether it kowtow to a good rule, or not. Local authorities and managers can then assess this rule with regard to another principle, or effects of the rule. In addition, LCA enables local authorities and managers to compare alternatives in different perceptions. More so, they are capable of distinguishing between perceptions that are either short-term or long-term. The distinction is that, in short-term perceptions, different systems have a constant production capacity, but variations in their utilization. In the perception that is long-term, different systems have different production capacity.
Also, different locations can be affected by the decisions of local authorities and managers, locations that are in the fore ground, that is, systems in waste management that are affected by the decisions can be easily identified (Barton, 1996, pp. 43). For instance, the incineration of the Foreground might be situated in the United Kingdom, in Sweden, or in another nation. With LCA, the local authorities are able to avoid burdens, which are correlated with production of energy. This energy is then replaced by incineration of waste paper, with energy recovery. LCAs long-term perception can result to an escalated consumption of heat and electricity. Thus, managers and local authorities ought to use this perception to find an alternative source of energy. For the future to be sustainable managers and local authorities ought not to probably use fossil fuels, especially not with the present emissions as an alternative, they should use an alternative source of energy. If the decision by managers and local authorities is to employ a policy that leads to an escalated rate of recycling, this policy will lead to ecological gain of an escalated recycling even though, the policy may not be effective if it stimulates paper collection in a limited area.
Different LCAs have resulted to different conclusions with regard to the option that is best for managing paper waste, that is incineration, composition, recycling, or land fill. LCA has made waste managers and local authorities to understand that recycling of paper wastes have lower ecological consequence. However, this assumption contradicts the conclusions from other studies. The discrepancy can largely be elucidated disparities regarding the energy source that is surrogated by energy from incineration of waste paper. Local authorities and waste managers ought to understand this so as to avoid burdens. Nevertheless, Life Cycle Analysis, have assisted them to understand that nowadays, fuel competition is also a type of solid waste, and fossil fuels is the main source of competition for energy. Lastly, from LCA studies, waste managers as well as local authorities have been able to conclude that emissions of NOX, dust, and oxygen exhausting emissions from water, and green house houses, are lower in the recycling process and the total amount of the land filled solid waste is usually lower in the recycling base (Barton (1996, pp. 47).
Current debates on waste management option
The environment issues of various waste management methods for paper material are the topic of a continuing debate. Indeed, numerous LCAs have been carried out regarding and assessed regarding this subject. The main issue of contention regarding recycling and incineration is the amount of energy recovered from packaging materials. Accordingly, varying LCAs have achieved varying conclusions concerning the best option to be applied in waste paper management, if it is recycling or incineration. Many have concluded that recycling of paper material at the moment leads t lower environmental effects in relation to parameters used. However, this conclusion differed with other previous studies.
This difference can mainly be explained through differences concerning the type of energy source replaced during the incineration. Whereas others studies conclude that at the moment the competing fuels are normally the varieties of solid wastes, some other studies are founded on the presumption that the fossil fuels are the main competing energy source.
However, in studies undertaken by Finnveden et al (1995) regarding this issue, it was established that
The net application of energy was lesser where recycling was used
The net utilization of biomass was lesser in recycling method
The emissions of gases such as NOx was lesser in recycling
The net amount of solid waste in landfills was lesser when recycling was used
The utilization of fossil fuels could either rise or reduce.
Dust emissions where lower in recycling processes
Basing the above parameters it can be clearly agued that recycling option will result in lower environmental loads. The only exceptions are utilization of fossil fuels, which may end up either increasing or decreasing. However, there is still no 100 answer to the overall question between recycling and incineration, which is the better option when it comes to management of waste paper. This is certain even in a situation where the answer is limited to CO2 emissions or the effect on climate changes. When using LCA, the results depends on the specific methodology used, which in turn depends on the appropriate perspective.
To get a correct answer, the overall questions should be specified exceptionally carefully in relation to the decision required, and what is implied by the term environmentally better, the time perspective as well as the graphical area also needs to be taken into account (Al-Humoud, 2002, pp. 412).
Conclusion
As discussed above, Environmental Life Assessment (LCA) entails studying the environmental aspects as well as the possible effects throughout a products life, beginning from the raw material acquired from the production to the end of that material disposed as a waste product. Before assessing the environment various considerations have to be undertaken, among these considerations are the use of LCA in waste management considerations in evaluation of ecological consequences of waste disposal, why local authorities and are using LCA for decision the option that is best.Presently, the ongoing debate is whether waste paper material should be recycled or incinerated, to achieve better energy recovery. This debate remains inconclusive since different studies have reached at different results. Nonetheless with present environmental concerns and the need to develop friendly environmental practices, LCA remains important methodology in waste management
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