Junk Mail - Raw Materials
Process industries are an important aspect of operations management as they have peculiar characteristics compared to discrete manufacturing industries. Various chemical processes happen in a closed manufacturing setup and finished goods are obtained at the end of the manufacturing process. In some cases, it is possible to derive products during the intermediate process in the form of byproducts.
This section discusses the process of paper manufacturing as the main issue, which include raw material acquisition, logging and chopping, crushing, processing, cleaning and bleaching, wood pulp refining, drying of the wood pulp and finally packaging. The logistical aspects of distribution and transportation of the products and waste management are also discussed.
Raw material acquisition
The process of material acquisition for papermaking is long. It starts by identifying the trees to be planted followed by the farms where they are to be planted. On the tree farms, trees are planted in rows, and given care throughout their growth period. At the proper time, they are harvested. The process of material acquisition, therefore begins at the nursery, where superior seedlings are produced. Research goes into the selection, and production of seeds from high quality seeds from high quality seeds that are resistant to diseases and grow rapidly. Many of the seedlings are crosses between two species or strains of trees. When they have grown to a certain stage in the nursery, they are transferred to the plantation farm. Succession is controlled by thinning the tree. As the tree grows and begin to compete for each other for sunlight and nutrients, some are harvested. Usually the trees cut are those that are slow growing or poor in quality. The best trees are kept. The trees harvested in the thinning process are good for paper production.
After felling and some on site processing, logs or trees are transported from the plantation to a central area. From the central area, they are loaded into trucks or trailers for transport to the paper processing plant. This is the primary transport.
The process of paper manufacturing
The figure below shows an example of a typical process industry, in this case paper manufacturing, in simple terms.
Figure: Diagram flow process of making paper
An analysis of the paper manufacturing process will reveal several features of the process industry. There are three stages in the in the paper manufacturing process. The first stages are the preparatory stage where logs of woods and chips of various sizes are first fed into the system. The logs of wood are and the chips are broken down into smaller and uniform pieces in a crusher. After the pieces are cut into smaller pieces, they are cooked in a huge chamber where some chemicals are added. During the process of cooking, the pieces are digested and the fibers are laid in a uniform pattern. This is done through a chemical process that are part of the process. After the process is complete, it is ready for making wood pulp.
The pulp making process is nothing but a further refining of the wood fiber and cleaning and bleaching of the material. Finally, excess moisture is removed from the pulp. At this stage, the pulp is almost devoid of moisture and near solid state. Therefore, it is possible to press it into the required thickness and further moisture can be removed. This is the last stage of the process known as papermaking. The dried and processed paper can be rolled into reels, and cut to required length, and shape.
At this stage, the product is the raw material that can be used for the various uses of paper. These include writing materials such as exercise books, notebooks. Printing materials for textbooks and others are also included. The next section is the logistic that enable the transport and distribution of the paper-manufactured process described above.
Ink production printing process
Colored ink production is just similar to other ink production. It is basically a carrier with a pigment for the color. In modern printing works, pigments are obtained from nitrogen components and selected salts. This ink is used in offset printing process.
The offset printing process is now the most widely used process for printing papers the basic principle of offsets lithography relies on mechanical damping of a printing plate which consists of an oleophilic image area and a hydrophobic non-image area. The plate is then inked and put into contact with a rubber blanket which, under pressure, transfers the image to the printing substrate. On the printing plate the image areas are covered with water. Intimate contact between ink and water must lead to emulsion being formed between the two. The ink then dries aided by the oxidation process.
Transport and distribution
This paper conforms with the hierarchical approach to logistics system analysis. This one of the approach that has recently been used as an effective tool for logistic problems. The separation of strategic or long-term logistic decision can greatly simplify logistics system analysis. The figure below shows the logistic system analysis structure.
Figure: Logistic system analysis structure
There are a number of logistics tradeoffs in the logistic system design that are important to be explicitly considered as part of the logistic system analysis. The importance of each trade-off differs as part of the distribution and transport concern for the industry or company. In general, they include:
Transit Cost versus Warehouse cost. In most distribution and transport system, or in simpler terms, logistic system, come economies of scale. This can be obtained through the use of the national warehouse network, if they are in place. This is because, with more warehouse, the transit cost of the customer is reduced, allowing shipment to warehouses to be accomplished in economical loads. However, numerous houses increase warehousing, and event inventory costs.
Another factor considered in transport and distribution of the products such as this is the proximity to the source of the raw material versus proximity to the customer. For a national producer, which in most cases paper manufacturers are, it is good to locate the manufacturing plant near the source of the raw material. This is because proximity to the raw materials is particularly important in industries where transportation costs are high. The paper industry has high transportation cost hence appropriate for the industry. Manufacturing industry must be located near the source of the raw material or very close to the transportation link. This must be in line with the service requirements and distribution cost structures that might suggest locating the manufacturing facilities close to warehouse locations.
The transport and distribution will depend on the two options described above. The specific use of the cost element analysis depends upon the level of complexity of logistic system. The basic form of cost element analysis simply determines alternative cost functions which include transportation, distribution and other operating costs a function of basic variables. With the development of the transport and distribution cost, its cost is related to basic activity such as the flow through the facility. Cost element analysis will be used to determine the cost of transportation and distribution within the logistics system. Local transportation costs, that is transportation cost of local production plant or warehouse to customers or consumers, may be estimated directly using freight rates. This considers the cost to each market and calculating a weighted average local transport rates to each targeted market and calculating a weighted local transport cost by multiplying and totaling the rate for each targeted market by its share of the warehouse location anticipated demand.
The functional relationship of transit cost has been often in the form of constant plus a second consultant time distance. Cost element analysis shows that such functional form may be valid for all regions of the country. The consultant should vary according to the region of the country or the direction where the finished paper product is being transported for consumption or use.
Transportation and distribution cost over different connection or transit links in the system, such as between the warehouse or between plants and warehouses, usually can derive using cost element analysis. If the transit system is not extensive, specific transportation rates can be obtained for each transit link, and transit cost estimated using the individual rates and volumes. Sometimes the network is too large and there are a number of links. A great many transport and distribution system design must be evaluated. It is impractical to obtain realistic rate quotations over proposed links that are not correctly used by the company, then the analysis requires the development of the functional relationship in order to estimate transport costs over some or all of the links in the transport and distribution network being evaluated.
The discussion ensures that the paper has been produced and has been delivered to the primary consumers. The primary consumer under consideration in this case is the advertising producers. After paper has been printed, they are passed on the secondary consumers of the papermaking product. There is need for a proper way to manage it by recycling. The next section focuses on paper recycling to produce paper for advertising mail.
This process actually begins with the collection of waste paper collection process as mentioned above. The purpose of recycling is to produce a pup with optical and physical properties which are acceptable for their end use. When recycled fibers are processed to produce print, the recycle facility is referred to as a dying plant. The exact configuration of the process equipment varies. The major operations of a deinking plant are pulping, screening, cleaning, deinking, dispersion, bleaching, solid-waste handling and water clarification.
The deinking technology that is utilized in the production of paper from recycled fibers is well established. However, the technology which is widely developed mainly in North America differs with others developed in other parts of the world such as Europe and Asia. Some of the factors that have influence of paper production are
- The quality of the intended product
- The availability water, power and other resources
- The properties of the waste paper
- The recycle fiber percentage in the finish
- Environmental regulation
- The process of paper pulp separation
The process of recycling paper requires the separation of the paper fraction from the aluminum and polyethylene layers. The process steps involved are cutting, soaking, re-pulping, and screening. The different recycling stages are described below in more detail.
The first step is cutting. This stage requires wastepaper and are cut with scissors into pieces to decrease their size and increase their surface area. This is necessary to facilitate the re-pulping process for paper recycling and reduce the time required to refine the fiber and form the pulp.
The second step is soaking. The wastepaper that has been cut into pieces is put in a tank filled with water and left overnight before pulping. This reduces the time required to refine the fibers for pulping and accordingly increases the pulper facility capacity.
The next step is re-pulping. Two available alternative technologies are used for re-pulping to separate pulp from Al and PE. The first alternative uses a hydropulper, which operates like a blender. The cut paper materials and water are added in the hydropulper where they are vigorously mixed resulting in friction forces between the materials that accordingly leads to the separation of the fibers from unwanted materials. The second alternative uses a beater. The cut paper pieces and water are added in the beater and circulate in its oval tank. As they circulate, they pass in between a rotating drum and a bed plate. This leads to separation of the paper fibers due to impact and high friction. Continuous circulation of the material in the tank results in refining the fibers.
The fourth step is screening. This stage main objective is to remove the pulp from the unwanted waste. Water and the re-pulped material is added to the screening device from the top. An air injection system is used to blow air through the water containing the suspended materials for a few minutes to avoid blocking the screens and allow efficient separation of the materials from each other. The airflow is stopped and a water valve at the bottom of the device is open for draining water. The pulp produced is obtained by being removed from the screen at the bottom.
In conclusion, a keen study will show that the advertising industry and also the paper industry utilizes a certain amount of waste materials such as the one discussed above as raw materials especially recycled fibers. Some, of the key recycling procedures are a utilization of filter or strainers to recycle secondary fibers, recycling, and reuse of water, and solvents used for cleaning operations can be recycled.
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Professor Christina Cogdell
13 March 2013
Junk Mail and Its Impact on Our Environment
The production of junk mail, defined for this research paper as advertisements in its paper form which are typically found in mailboxes, both in color and black and white, involves many processes for it to eventually reach the mailbox. Considering the paper manufacturing process, printing ink production, transportation, and also recycling, junk mail has a negative impact on the environment because of the many kinds of wastes that each and every production process creates. Despite the recycling efforts to create an environmentally friendly alternative to paper production, there are still both increasing air and water pollution being released into the ecosystem, affecting both human and animal life. Taking into account the entire life cycle of junk mail from the beginning of paper as a tree to eventually either its recycling or incineration, the amount of energy, resources, and thus the environmental impact it has on the world is a serious concern.
The creation process of paper begins with a tree, or more specifically, the fibers that are produced “biosynthetically as plant cells” (Roberts, 11). Understanding that the non-recycled paper, or, the original copy of paper is produced from large quantities of wood, we can explore the amount of waste produced from this part of the life cycle. According to the U.S. Environmental Protection Agency, the pulp and paper industry in America produce “9 million tons of pulp” a year, accounting for “35% of pulp produced in the world.” Wood’s two primary components that make up the pulp are its cellulose and lignin. During the pulping process, chemicals are typically used to alter and break down the ingredients’ structure which emits toxic fumes and pollutants such as “formaldehyde, methanol, acetaldehyde, and methyl ethyl ketone” (EPA.org). Afterwards, the pulp has to be washed “at high temperatures which generates a large volume of exhaust gases” and chemical fumes into the air (EPA.org). The waste from the initial pulping process is only a portion of other dangerous pollutants that are a result of paper production. A major controversy for the paper industry occurred in the 1990s when large amounts of dioxins were discovered in many food products such as “meat, dairy, fish, and shellfish…” which not only posed an environmental threat but also a risk to human lives (WHO.int). Dioxins are a product of using chlorine to bleach paper to be as white as we are normally use to and caused many serious health issues, especially when it was discovered in the wastewater (Popp, 1). According to the EPA, dioxin has been discovered to cause cancer once “a living creature has been exposed to dioxins… at high enough levels.” This became an obvious issue for the paper industry but as well as for the inhabitants around the pulp mills and industrial plants.
With the concern and debates around dioxin during the 1990s, the paper industry began to look for alternative methods to bleaching paper. International campaigns by Greenpeace, the Women’s Environmental Network, and other non-government organizations pushed for the paper industry to adopt elemental chlorine-free (ECF) and total-chlorine free (TCF) technologies that eliminated majority of the toxic pollutants to become more environmentally friendly (Sonnenfeld, 9-11). Both ECF and TCF technologies aimed to decrease or eliminate the use of chlorine and are still in use today, with majority of plants taking advantage of ECF and its chlorine dioxide compound to eliminate the toxic carcinogen -- dioxin (Popp, 5). For mass production paper, such as the kind being distributed for low cost and efficient advertisement, it is much more likely that companies would opt for TCF bleached paper because of its lower costs but lesser quality paper. This is the case because TCF bleaching uses no chlorine at all, resulting in the best environmental performance of the pair (6).
Along with toxic chemicals, paper production creates other types of waste as well, such as paper sludge and biodegradable nutrients. Paper sludge consists of the leftover fibers, inorganic materials, and chemical residue that are not fit for paper production and must be disposed of from the paper mill (Das, 129). Currently, “the residue from pulp and paper mills is handled by… [disposing it] to the land in the form of solid waste” (Scott, 239). Therefore, they are taken to landfills and left to decompose. According to Gary M. Scott’s research, America is producing approximately “4.1 million dry tons of sludge… each year” and is only increasing from here (239). The issue the paper industry currently faces is that landfills will eventually reach capacity, forcing them to find new waste disposing methods. Currently, the alternative to landfill storing is incineration which releases air pollutants including sulfur dioxide, nitrogen dioxide, nitric oxide, and carbon monoxide (Wang, 92). However, not all sludge is considered to have a negative impact on the environment. “High-fiber-content sludge could be used as animal bedding or for ethanol production” to lower landfill and incineration percentages and become usable material in a form of reusing “waste” (Scott, 242). The other variety of waste that is a frequent product of paper mills are biodegradable nutrients, typically found in the sewage outflow and accidental spillage that contain organic molecules potentially fatal to aquatic ecosystems. The carbohydrates from wood that feed and grow microorganisms can deoxygenate an entire body of water if left unregulated (Roberts, 166). These types of wastes produced by the initial paper production do not include the other environmental hazards printing and other processes required to produce junk mail.
Once the paper has been properly manufactured, the printing industry is required to produce quality inks for the advertisements and mail that are meant for the consumer. The mass production of ink poses threats to both the environment and human health because of the “hazardous air pollutants (HAPs)… such as volatile organic compounds (VOCs) including benzene, toluene, and xylene” that have been known to cause serious health issues (Djogo, 101). Additionally, VOCs are known to be a contributor to ozone which is dangerous to human health and has been found to be a cause of lung cancer (103). While the printing ink industry has began to adopt water-based inks to minimize chemical pollutants and VOC emissions, there has been an increase in pollution within the wastewater after cleaning, causing the water to contain “high levels of colored pigments and organic materials” (101). These air pollutants are a result of the many various chemicals required to produce ink at an industrial level and even with governmental regulations, it still remain an issue for the industry and the environment. To mitigate a portion of the large quantities of waste and emissions, the paper industry has attempted and is continuing to advocate reusable resources as the “green” alternative.
Recycling is a relatively new idea of environmental conservation that came about to address the ever-increasing demand for supplies and is defined in the Oxford English Dictionary as “reus[ing] material in an industrial process” (1.a). According to an EPA research on what Americans have in their trash, paper constitutes 40.4% or 71.6 million tons of waste throughout the entire country. By recycling, there are the obvious advantages such as less pulp manufacturing and wood-cutting, but a major disadvantage to recycling paper, particularly printed paper, is the use of de-inking chemicals to separate the paper from the ink (Roberts, 163). This becomes an issue once the “ink-rich waste … must then be disposed of… impos[ing] a burden on the effluent treatment system,” producing more water and chemical waste (164). With how much junk mail comes through to mailboxes through the post office, majority of the paper would be colored or printed on, and typically then tossed away to be recycled. Taking into consideration the possibility that not 100% of paper is recycled, whether it is due to economical reasons or simply people not bothering to separate their trash and their recycling, which study shows that “20-25% of domestic refuse is still made up of paper,” it is evident that recycling has yet to become entirely efficient and environmentally friendly (154). Additionally, once the junk mail arrives to the recycling facility, the de-inking process is similar to the bleaching process used in producing new paper and along with it, the same type of environmental issues such as toxic chemicals and fumes (Roberts, 160).
De-inking removes ink and toner from the paper to allow the wastepaper pulp to enter the recycling process without any contamination. There are two types of ink printing, known as impact and nonimpact ink. Impact ink is normally used in newspaper printing while nonimpact ink produces much higher quality prints, but in turn, makes them much more difficult to de-ink (Lee, 3809). Generally, sodium hydroxide is used to loosen ink particles from the paper’s fiber that ultimately is removed from the pulp mixture (Roberts 159). The remaining residue from the pulp mixture, referred to as de-inking paper sludge, is left to either decompose in a landfill or incinerated, releasing high amounts of carbon and nitrogen into the air (Mendez, 736). Typically, new pulp must be mixed in with the recycled pulp to produce a certain degree of rigidity. Furthermore, to reach a specific amount of brightness, the same ECF or TCF bleaching methods used on new paper must also be used here, producing the same emissions as when new paper is bleached (160). While recycling conserves resources such as wood, there is still the issue of being able to maintain and produce similar paper through recycling as if it was new, which still requires many other resources that continue to produce and inevitably increases the amount of waste the paper industry releases.
A major resource for the production of paper, its printing, and its recycling is water as it plays a crucial role in the overall process. In a paper mill, a total of approximately 29,000 m3 of water is used to produce a day’s worth of paper (Manikavasagam, 172). While the modern paper mill aims to reuse their wastewater through processing and recycling, there is still wastewater being runoff into streams or rivers that eventually connect to the ocean (Richards, 172). With the paper mills consuming the majority of water needed throughout the entire junk mail life cycle, “environmental legislation concerned with water scarcity” is demanding the paper industry to “adopt a zero liquid effluent policy” to minimize the amount of wastewater wasted (Hermosilla, 1236). To do this, reverse osmosis in a closed water circuit is utilized to constantly reuse resources but still produces a high concentration of organic and inorganic matter that must be disposed of as an effluent (1237). By placing new technologies for processing wastewater, the paper industry is decreasing the amount of effluents that are a result of their manufacturing, but still has yet to create a totally effective and environmentally sound process.
Another major environmental waste producer throughout junk mail’s life cycle is transportation. The air pollutants from trucks ranging from large heavy duty vehicles to light duty delivery vans all contribute to increases in greenhouse gases and decreases in air quality. According to the EPA, greenhouse gases consist of “carbon dioxide, methane, nitrous oxide, and various hydrofluorocarbons,” all of which are products of fuel combustion. While exact percentages could not be found for the life cycle of junk mail in particular, the many stages of transportation for paper can still be examined. Beginning with the cut lumber to the creation of an advertisement and its delivery to your mailbox, and eventually to the recycling facilities to begin the life cycle again requires many forms of transportation. Currently, all heavy-duty trucks and in this case, many of the United States Postal Service’s delivery trucks burn gasoline or diesel which Colls states in his research that only 30% of the combustion energy is harnessed within a vehicle (Colls 2002). He also points out that despite the fact that diesel engine trucks “make up [only] around 3% of the vehicle population and travelled 5% of the miles,” over 50% of vehicle emissions still come from the heavy duty sector. Considering the amount of trucks that it takes to transport paper and the other required materials, such as chemicals, machinery, and general distribution, there is an unfavorable product to emissions ratio for the industry.
Additionally, continuing through the junk mail’s life cycle, the United States Postal Service (USPS) plays a significant role as they deliver the junk mail to mailboxes in every town. Since 1987, the USPS has been delivering mail in Long-Life Vehicles (LLVs) designed by Grumman to last 24 years (Energy.gov). The LLVs are equipped with a gasoline engine that produces the same kinds of emissions and exhaust as a normal passenger vehicle. With over 100,000 LLVs in the USPS fleet, they are delivering over 279.5 million pieces of advertising junk mail throughout the country a day, driving 4 million miles and constantly releasing greenhouse gases (USPS). Granted, the USPS is currently in the transition of becoming a more sustainable business by utilizing “more than 44,000” alternative fuel-using vehicles, but has yet to completely minimize their emissions footprint (USPS).
Going beyond emissions in the United States, paper recycling has become an economical benefit as well as an environmental one for developing countries such as China. By exporting American paper waste to be recycled in China, which is then made into paper products to be shipped back to Western countries, creates a theoretically never-ending cycle of reusable resources (Terazono, 83). This ideal cycle appears to be an effective process for paper recycling, but research on emissions of cargo ships shows that up to two thousand times more greenhouse gases are produced by ships than by automobiles (BP.com). The “carbon dioxide emissions from ships equals 4% of the global total” and just BP’s ship fleet alone burned 220 million tons of fuel in 2007 (BP.com). Despite the positive effects of the never-ending life cycle of paper recycling through exportation, there are still inevitable and significant emissions from global transportation using cargo ships.
Throughout the entire process for junk mail to begin as wood and to eventually be recycled, there is a substantial environmental impact, despite the industries’ efforts to minimize their wastes and emissions footprint with new technologies. In this research, while there was no exact quantification of how large of a contributor advertising mail itself is within the world’s environmental pollution, there is still considerable evidence to prove that the overall infrastructure requires improvement and should continue to look for alternatives to decrease emissions. The stages, including paper production, ink production, transportation, and even recycling have emissions and waste consisting mainly of different air emissions and solid waste. Beyond that, water waste is also a major issue for the production of junk mail and printed-paper in general. The measures that government legislation are passing signify the attempted reforms to improve this known issue but has yet to come to any definite and absolutely sustainable results.
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