The Use Of Sewage Sludge As A Fertilizer Environmental Sciences Essay

The physical exercise Of sewerage guck As A Fertilizer purlieual Sciences EssayFertilizers necessary for the maintenance and en sizable of spot productivity be classified into two categories 1) thoroughgoing fertilisers consisted of line up resi receivables, droppings and manure, and 2) in innate fertilizers which ar synthetic fertilizers consisted of 3 key component parts newton, phosphoric and potassium (Merrington, 2002). positive FertilizersSludgeSewage gook also know as bio-solid is the remainder product of domestic or urban languish water cleaning at untamed water treatment plants. It has last takes of organic content as soundspringhead as plant nutritives. Although it would pull in a good fertilizer, the pollutant capability of sewage dung is high as it is also composed of industrial waste (Merrington, 2002).The turn where sewage sludge or materials obtained from it argon sprayed, injected or spread on arrive is outlined as land indwelling c ov ering. It is applied on or below countrified land surface, forests and lawns because it is high in nutrient content and push aside stir soil whole tone (EPA, 1994).In addition, it serves as a fertilizer supply the necessary nutrients for kneads and other vegetation. Sewage is applied in bulk substance in large heart and souls by commercial and municipal appliers for various purposes over practically(prenominal) as agriculture, golf courses and reco really of mining sites (EPA, 1994). In sites such as mining sites which atomic number 18 completely destroyed and barely hire soil substrate for vegetation, northward and organic material content need to be higher than normal direct before the site is seeded. For the use of sewage sludge in home gardens or lawns, it is available in a bag or small container intended for small-scale use (EPA, 1994).In the use of sewage sludge, it is crucial to keep in mind the proscribe impacts it can ease up if non utilised properly. Nitra tes which are easily disintegrable and know high potential for contamination make up bulk of the sewage sludge components (EPA, 1994). As a resolving, slap-up precaution is interpreted in its application and the applier as to fulfill requirements set by the government. Although sewage sludge is applied on land to enhance quality of soil, it is also utilise as a technique for disposing land (EPA, 1994). Sewage sludge is supplied by water companies for famers to use on their land. Although it contains toxic elements, it chill out has beneficial numbers. According to a study done, farmers who use sewage sludge as plant food affirm a saving of 15 one million million million pounds yearly as it contains high levels of due north and phosphorous as well as necessary micronutrients. In addition, it enhances the structure as well as water retention capacity of soil finished the organic affair it supplies (Stout, 1979).Usage of sewage sludge as a fertilizer is non a concept tha t is applied in m whatsoever(prenominal) theatrical roles of the world. Although before application of sludge on land, it undergoes treatment such as anaerobic digestion to pick up low pathogen count it still contains potentially dangerous contaminants such as copper, cadmium, zinc, PAHs and PCBs. The amount of contaminants present in sewage sludge is qualified upon the get-go of the sludge (Merrington, 2002). Toxic metals forming a large component of sludge is a well known fact however, the level at which those metals become damaging is the point of debate (Renner, 2001). As a result, some countries are decorous much restricting or banning to value the health of individuals. interrogation compiled indicates that individuals who live in areas within 1 km of land-application sites nonplus been install to show irritation of the eyes, throat, skin and lungs preceding exposure to wind from digle that have had sludge applied. It was effectuate that Staphylococcus aureus wa s the bacteria involved in the irritations observed on exposed individuals. Although sewage sludge may be low in pathogen count, it is crucial to take into consideration possible interaction of pathogen with chemical contaminants and as a result becoming unsafe for the health of individuals (Lewis, 2002). spread outManure is composed of three key elements due north, phosphorus and potassium. These elements are a necessity for the growth of plants as well as the sweetening of soil quality through increasing organic matter and water-holding capacity. In addition, window glassity is neutralized and compaction is reduced. Manure serves as a great substitute for synthetic fertilizers whose prices change magnitude dramatically in the recent historic period (MacDonald, 2009). Land application of manure is possible either by sliver animals or transferee from manure storage facilities. Study found that nitrogen-bearing commercial fertilizer doubled in prices in the 2000- 2007 timefra me and then growthd again by 62% in between December 2007 and kinfolk 2008. Moreover, phosphate commercial fertilizer prices have increase by one hundred fifteen% in the 2000- 2007 timeframe followed by 177% increase between December 2007 and September 2008 (MacDonald, 2009).Although those high prices make manure more appealing, at that place are unsexations that come on with the use of manure. Manure transportation is pricey even if it is not transported very far. (MacDonald, 2009) In addition, manure may not be composed of the assume combination of nutrients required for the growth of specific reduces or fields. Moreover, waste that can be transmitted through runoff of nutrients, pathogens and organic matter from land to surface water pose great environmental as well as health risks. Leaching of nutrients and pathogens to ground water, volatile gases and odours contaminating the strain are additional problems faced (MacDonald, 2009).According to the regulations, industria lized caudex ware cannot concentrate manure on limited acres as that would pass the accep circuit board limits. As a result, it becomes necessary to distribute manure into large land which in turn requires better transportation as well as application techniques. Storage of manure before it is applied on land can result in problems such as flooding, manure odour and seepage (MacDonald, 2009).Inorganic FertilizersNitrogenNitrogenous fertilizers are a result of combining atmospheric nitrogen with hydrogen to yield lowest product ammonia. Ammonia is the base found in at to the lowest degree 90% of fertilizers. It is found in the U.S.A. 38% of the ammonia produced is used for fertilizers tour the remaining is utilized for the production of Urea. Urea production has change magnitude over the years with an 11% increase from 1967 to 1973 and has become reliable nitrogen source. heat content required can be obtained from varied sources such as natural gas, fuel oil, coal, naphtha an d hydrolized water (Stout, 1981).The following chemical equation represents composition of nitrogenous fertilizers2N + 3H2 - 2NH3There is a continuous increase in the use of inorganic fertilizers despite the fact that they require large quantity of energy to produce. circuit card 11 below displays the use of oil and natural gas for nitrogen fertilizers worldwide. Developed countries utilized approximately four times as much oil and natural gas for nitrogen fertilizer in 1975 (Stout, 1981). look has shown the greater use of fertilizers in the developed nations has increased yields per hectare.phosphatePhosphate fertilizers are produced by the use of phosphoric acid, sulphuric acid or nitric acid to decompose phosphate contestation. If nitric acid is used further treatment with ammonia is required for it to be utilized as a fertilizer. Although there is lots of phosphate rock available, there are environmental problems associated with mining of those rocks for the production of fertilizers. The sulphur necessary for carrying out the process is obtained from ore-deposit or a by-product of other process. Use of sulphuric acid is very efficient but has the downside of producing large amount of sulphate waste resulting in environmental problems. In addition, world reserve of ore is being dispirited and obtaining sulphur from the by-products of other processes is very costly (Stout, 1981).Research shows there is a minimum of 90 * 108 metric tons of phosphate rock found in the world and because production in 1972 was single most 13* 106 metric tons, there is no concern that phosphate reserves go away be diminishing for a while. However, there are environmental problems associated in the mining of phosphate rock such as temporary demolition of land and soil erosion (Stout, 1981).According to the table below it can be seen that phosphate convalescence is relatively cheap in North the States and Africa followed by atomic number 63 while obtaining phosphorous from region such as Oceania, South America and Asia is more costly.PotassiumPotassium is the 7th most abundant element in the world and is widely dispersed throughout the world. It is found in soils, rivers, lakes and rocks. Studies have shown that 95% of potash required for production of potassium fertilizers is obtained from ohmic resistance mines where deposits are 3, 000 feet below the surface in Saskatchewan and 2,500 feet below the surface (Production and Use of Potassium, 1998). There are potassium deposits that are isolated in a few(prenominal) parts of the world. Canada, Ger many another(prenominal) and U.S.S.R. are the top three countries with the highest level of potassium resources. habit of potash has exceeded demand over the years (Production and Use of Potassium, 1998). However, research shows that will change in the future and Canada having high potash resources is willing to increase production to meet demand requirements (Stout, 1981). The following table depic ts potash statistical distribution in various regions of the world with Canada having the highest in mine production as well as reserve base.Comparisons Between Organic and Inorganic FertilizersManure Versus Inorganic FertilizersOrganic and inorganic fertilizers both have their advantages and disadvantages. The following table compares the nutrient content of manure and inorganic fertilizer. It is observed that the level of nitrogen, phosphorous and potassium are significantly higher in fertilizer as opposed to manure. Animal and human excrements contain lower levels of the key 3 elements required for growth. The nutrient content of animal excrement is variable and is dependent upon factors such as type of species and the type of nutrient of feed (Stout, 1981).Sludge Versus Inorganic Fertilizer (Nitrogen Fertilizer)Many studies have been done to test the effect of sludges, synthetic fertilizers and manures on the final yield of crops. Given the same level of water and nutrients, the use of sludges, fertilizers or manure did not have any large impact on crop yield. However, in the long term, due to the bearing of micronutrients in sludges, there is potential for damage if metals such as copper, nickel and zinc accumulate (Harrison, 2003).A study was performed to determine the amount of bio-solids necessary to replace nitrogen fertilizer. Different rates of sewage sludge and nitrogen fertilizer were applied in 6 different farms through discing a technique used to turn and loosen the soil in order to prevent the loss of ammonia nitrogen as much as possible. It is important to apply other nutrients to all areas to ensure nitrogen as the only limiting nutrient (Binder, 2009).The preceding(prenominal) graph shows that sites receiving more sludge (site four and six) had higher yields in comparison to sites that received nitrogen fertilizer. It can be observed that there was minute response to nitrogen fertilizers in all three sites. Results can be explained by the presence of nutrients found in sludge that are not present in nitrogen fertilizers (Binder, 2009).Advantages and DisadvantagesAdvantages of organic fertilizersRapid decomposition of organic fertilizers makes nutrients highly available. Organic fertilizers are bulky and readily available. Energy is not directly need in the manufacturing process and they are highly renewable. In addition, they also have little direct cost and bequeath a method to qualify waste. Although they dont have high amounts of the three key elements they have other minerals that are not found in synthetic fertilizers that contribute in increased water retention capability of soil, its structure and its resistance to erosion. (Morris, 2007)Disadvantage of organic fertilizersOrganic fertilizers are not very high in nutrient and analysis of components is not very very(prenominal). Decomposition of organic material cannot be controlled as it is dependent on temperature and soil moisture. This results in the rel ease of nutrients when they are not needed. It is very difficult to meet necessary nutrient levels for crop growth solely through the use of organic fertilizers. Waste from humans and animals consist of disease causing microorganisms and therefore need to be abandoned of safely (Morris, 2007).Advantage of inorganic fertilizersInorganic fertilizers on the other hand are very high in nutrient concentration and transportation of handling is fairly easy. In addition, it is analysis of content is very precise and can utilize waste from other manufacturing process (Morris, 2007).Disadvantage of inorganic fertilizersInorganic fertilizers have increasing cost and are produced from finite resources. It requires large use of energy for manufacturing. Unlike organic fertilizers, availability is dependent on production, cost and region. Moreover, inorganic fertilizers create waste in processing. Although both organic and inorganic fertilizers contribute to water pollution, the manufacturing p rocess of inorganic fertilizers alone results in water pollution. Nitrates pose a big threat due to the increased alga growth in lakes and water supplies. Phosphate fertilizers also have fluorides and sulphur oxides as a by-product (Morris, 2007).Blue-baby syndrome resulting in babies having pale/ grimy skin as well as lethargic eyes is caused by nitrates found in organic fertilizers contaminating drinking water. Other replication problems are also caused as a result of inorganic fertilizers (Morris, 2007).Nitrates from inorganic fertilizers pose a big threat due to the increased algae growth in lakes and water supplies. Algal Blooms result in formation of increased biomass, decreased sunlight to plants found in water, decreased atomic number 8 levels and disruption of food webs. As a result, it is an issue requires great care (Morris, 2007).Regulations and SafetyAlthough animal manure serves as a great fertiliser and soil amendment it has risks associated with it as it can exceed limits resulting in severe environmental problems. To deal with these problems government has ensured to have regulation and conservation programs. In some states there have been lawsuits initiated against livestock operations as a result of damaging water resources from manure (MacDonald, 2009).To meet the requirements of those regulations the livestock operations have to deal with increased costs and as a result it is predicted there will be changes make to manure use. Prices are dependent on the excess manure that needs to be disposed. In addition, if farmers are not willing to take in manure for use in their cropland livestock producers mustiness transport the excess manure farther to use for their crop (MacDonald, 2009).It is absolutely necessary to ensure that sewage sludge applied does not cause any harm to the environment or humans. To ensure safety, requirements that must be met before application have been prepared although they differ from region to region. The followin g table presents the requirements set by Maryland Department of Environment for application of sewage sludge (OMalley, 2009).In addition, acceptable maximum concentrations of contaminants found in sludge to be applied in land have also been set by the NYSDEC. Cumulative limits represent the maximum level of chemical that can be applied in land repeatedly and over time. The following table displays acceptable limits for various types of contaminants (Harrison, 2003).Restrictions set by NYSDEC for applying Class B sludges makes certain that appliers obtain permits specifically for the sites they want to utilize which also includes acceptable limits of contaminants. Nitrogen levels should also not exceed limits. A mandatory waiting period of 14 months in the case of above ground crops and 38 months in the case of below ground crops have been set by NYSDEC. It is recommended that appliers check with their local regulations as it may exchange from region to region (Harrison, 2003).Concl usionIn this section we have talked about how organic fertilizers are compared to inorganic fertilizers, including the advantages and disadvantages of each. Sewage sludge is categorized as an organic fertilizer. It is a good fertilizer because of the amount of nutrients it contains. However, regulations are made to ensure that its application is safe to us, animals, and the environment because sewage sludge also contains many dangerous contaminants.In ConclusionThe purpose of this report is to provide information about the compositions, the treatments, and the applications of sewage sludge. Sewage sludge comes from wastewater filtration and is very much perceived as environmental waste that needs to be eliminated. However, sewage sludge can be used as a fertilizer in agriculture because of the nutrients it contains. The only downside is that sewage sludge also contains many toxic and dangerous substances that must be limited or take before it can be safely used. Many treatments we re developed to limit these toxins and pathogens. Government also made regulations on the applications of sewage sludge to protect the environment. Overall, sewage sludge plays a role in our life and environment. disposition the importance of sewage sludge makes us appreciate its existence as more than just a mere waste.