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By Ing. Elías Jorge Matta
Even keeping the emission levels within the limits that they set themselves, in the medium or long term, the accumulation of pollutants in the food chain will transform the region: severe losses in quality of life; land depreciation and economic ventures; and unfortunately, also the deterioration of the health of the inhabitants of the region.
The purpose of this report is to describe - in summary form, the most important pollutants emitted by the bleached pulp mill that the firm "Botnia Fray Bentos S.A." (Fray Bentos, Oriental Republic of Uruguay) is operating in the town of the same name, on the Uruguay River. They are of great relevance to understand the environmental impact of these pollutants, the knowledge of the basic characteristics of these compounds and their effects on the possible receptors, the annual quantities that will be discharged and how they are distributed in the region.
This writing is preceded by various documents, articles and conferences by the author. Particularly noteworthy is his participation as Advisor for the Universidad Nacional del Litoral (Santa Fe) to the President of the Argentine Delegation in the Argentine-Uruguayan Binational Commission (GTAN / DA, 2005/2006) (1), the cooperation with the Argentine Foreign Ministry for the drafting of the responses to the first Reports of the International Finance Corporation (IFC, World Bank), the technical advice to the Argentine Foreign Ministry for the preparation of the Argentine Presentation before the International Court of Justice in the Request for Provisional Measure (June 2006 ). The Argentine Delegation that traveled to The Hague (Holland) to present said Provisional Measure was appointed Member.
We also highlight a recent and extensive article in three parts, published in the technical dissemination magazine "Ecociencia y Naturaleza" (N ° 3/4/5, ISSN1851-0620, M. Peña, Editor), "Proyectos Celulosicos de la República Oriental of Uruguay. The Environmental Risk "(2,3,4).
The description of the pollutants will be reduced to the permanent emissions that accompany the liquid effluents that end up in the Uruguay River and those emitted into the atmosphere, mainly by the plant chimneys, under "normal operation" conditions, which we consider the of greater relevance.
In consequence, pollutants in solid waste will not be considered; sporadic or occasional emissions, whether accidental or the result of "non-normal operation". Pollutants emitted by activities directly related to the operation of the plant, but which take place outside the plant's premises, such as forestry, river and land transportation, and others, are also outside the description.
II. Plant in Normal Operation
The concept of emissions during the "normal operation" of the plant, as understood in the industrial practice of the sector, the corresponding bibliography and documentation, implies that:
- The plant is out of its normally one-year start-up period.
- It operates 24 hours a day, from 340 to 350 days a year, producing according to design. In the case of Botnia Fray Bentos SA, 1,000,000 tons per year, at a rate of approximately 3,000-3,100 tons per day.
- The plant has all the mitigation systems also operating normally, in particular the primary and secondary liquid effluent treatment systems, as well as the filtering and flue gas scrubbing systems.
It should be taken into account that the Botnia Fray Bentos plant, according to the company, will produce in normal operation for no less than 35-40 consecutive years.
III. Bleached Kraft Pulp Plant. Contaminant Characteristics.
In modern bleached Kraft pulp plants, four main groups of contaminants are distinguished:
- Organic material in the final liquid effluents, whose degradation in the river by microorganisms consumes dissolved oxygen in the water.
- Highly Hazardous Gases, not all discharged from the main chimney.
- Cumulative Effect Pollutants.
- Particulate material.
Incidence of Pollutants on Receptors.
The effect of the various pollutants emitted by the plant on potential receptors, the so-called "environmental impact", is a highly complex issue. First, due to the quantity and variety of toxic compounds involved, which act both individually and in joint association (synergistic combined effects). Second, because there are also numerous receptors (flora, microorganisms, fauna, human beings), each of which has its own sensitivity to pollutants and their combinations. Third, because the interaction between receptors and pollutants can be very high and often not very predictable. We will not delve into these issues, clearly within the competence of medicine and biology, rather than chemistry.
III.1. Organic material in final liquid effluents, whose degradation in the river by microorganisms consumes dissolved oxygen in the water, essential oxygen for all river life. It is evaluated through various tests, the most common being the determination of the Biochemical Oxygen Demand (BOD5 or BOD5) and the Chemical Oxygen Demand (COD or COD). The greater the discharge of BOD5 and COD, in terms of Kg / day or Kg / year, the greater the risk for all the living inhabitants of the river, especially if the level of dissolved oxygen is, prior to discharge, relatively very low . This usually happens if the water temperature is high. Another factor to consider is the river flow (amount of water) in relation to the Kg of BOD that is being discharged in a period considered. Consequently, the relationship between the Kg O2 dissolved / m3 and the Kg of BOD / m3 is of importance. But this last value by itself does not represent anything, since the concentration of BOD does not have a main role in the degradation and consumption of oxygen.
III.2. Highly dangerous gases. Chlorine dioxide (ClO2), produced in the cellulose bleaching plant), and gases produced by combustion such as hydrogen sulfide (H2S), nitrogen oxides (NOx,) and sulfur dioxide (SO2). All have effects on living beings, an effect directly related to the product "toxicity" x concentration x exposure time. They can have very quick consequences, lethal or not, but also long-term effects, generated by repeated exposure to concentrations much lower than lethal. The concept of dangerousness or toxicity is relative, since allergic, predisposed or overly sensitive people react very differently when exposed to the same concentration of the pollutant for the same time.
III.3. Cumulative Effect Pollutants. Within this group are the organo-halogenated in general (AOX) and the Dioxins and Furans in particular. Also "heavy metals" (arsenic, lead, mercury, chromium, etc.). They are almost all highly toxic, but they hardly have immediate effects - except if they enter the bloodstream directly, since the most common entry of these contaminants into the receptor is through the digestive system. To a lesser extent, via the respiratory system. They have serious consequences (widely known today), usually in the long term.
The cycle of these pollutants begins when they are deposited and increase in grasslands, waterways and rivers (fixed to particles and sediments), since most are stable compounds that do not react or change for months or years. At some point, a living being ingests them involuntarily, initiating the second cycle of accumulation, known as the "food chain" or "food chain". They can be crustaceans or plankton in the aquatic environment; all types of livestock and poultry animals outside the aquatic environment, due to water and forage intake. In the case of Dioxins and Furans, the compounds are stored in tissues and fat cells. It is thus transferred to the rest of the food chain, through meat, milk (including breast milk) and eggs. It is estimated that currently in Europe a person ingests around 0.13-0.15 nanograms (ngTEQ) of Dioxins and Furans per day through their normal diet, mainly meat, fish and dairy products. The concentration of the contaminant in human fatty tissue varies from 3-35 ngTEQ / Kg, but can reach much higher values, depending on the level of contamination of the food.
III.4. Particulate material, especially PM10 and PM2.5, coming from the chimneys. They are a unique case of great impact on health, through the respiratory tract. Due to their small diameter, the particles are easily carried through the air, even over long distances. Upon entering the lungs, they cause severe irritation to the bronchial tubes and acute oxygen transfer and monoxide (respiratory) expulsion problems, which over time lead to cancer and heart disease. The particles are irritating even when they are chemically inert, such as grains of sand (quartz). The particles from chimneys (mostly calcium sulfate) are much more dangerous, because they contain - adsorbed on their surface, pollutants such as H2S, NOx, Dioxins and Furans, which exacerbate lung problems. This effect of particulate matter is noticeable even with very small concentrations in the air. And it worsens with repeated exposure, prolonged or not.
The particulate material that does not end up in the lungs of higher living beings (livestock and humans) is deposited in land and water, contributing with its pollutant load to chemically alter the river sediments and increase the content of toxins in the food chain.
IV. Discharge of Pollutants in Liquid Effluents to the Uruguay River.
Table 1 (Annex Tables) summarizes the main pollutants discharged into the river, according to Botnia SA, directly or in the reports submitted to the World Bank. As seen in the last column on the right, the compounds that consume dissolved oxygen from the river add up to hundreds or thousands of tons per year (BOD5, COD). Clearly toxic and cumulative compounds (Sulfides, AOX, Heavy Metals, Dioxins and Furans), are released in large quantities. No matter how you put them, the numbers are huge and staggering.
Table 2 is a compilation of the most relevant information on discharges from modern bleached Kraft pulp mills, worldwide, with the same or superior technology than that of Botnia Fray Bentos SA. The differences in some areas are disproportionate, which generates unavoidable doubts and questions about the information provided by Botnia SA.
The case of the Dioxin and Furan spills is undoubtedly one of the most worrying. As far as we know, the R.O. del Uruguay has not granted authorization to dump this type of compound with liquid effluents. But the World Bank report says the spill will be "less than 250 million" toxic units (ngTEQ), an unacceptably large amount, even if it were only ten times less.
V. Pollutants in Emissions to the Atmosphere.
Table 3 summarizes the main pollutants in the atmosphere, as reported by Botnia and B. Mundial. All values are extremely high, with more than 450 tons / year of particulate matter and several thousand tons / year in gaseous pollutants, including a (technically unclear) amount of 25 to 40 tons / year of hydrogen sulfide. H2S is a very odorous and toxic gas, the most important fraction of TRS, which is completed with mercaptans, in much lower percentages. Mercaptans are even more odorous than H2S, so that even in very low concentrations they are clearly perceived. Hydrogen sulfide and mercaptans give the characteristic smell of a Kraft plant.
There are no major discrepancies with third party references (Table 4), except for Dioxins and Furans. When in the world it is recognized that a chimney emission of 20-28 ngTEQ per ton of pulp produced is usual, Botnia does not report emissions of Dioxins and Furans. Strangely, the only authorization from the RO of Uruguay to Botnia Fray Bentos SA, in relation to Dioxins and Furans (5), says that the emission into the atmosphere of the company "... may not exceed the value of 163 mg eqt / year" , or what is equal, 163 million toxic units (ng TEQ) per year.
It is convenient to emphasize - again, that the amount of each pollutant that appears in all the Tables, including third party references, must be considered minimum or optimal quantities: those that a perfectly designed, built and operated plant would emit, without considering - as stated above, accidents or "non-normal" periods, which the company recognizes will occur.
SAW. Distribution of Pollutants and Transboundary Effects
As has been explained in previous writings (3), the bulk of the pollutants, emitted by the chimneys or with the liquid effluents, will remain around the area surrounding the plant. Possibly 45-60% of the values that appear in the Tables will be deposited in a radius not greater than 25 km. An additional 15-25% in the area ranging from 25 to 60 km. Not more than 20% it will be deposited at further distances.
All the pollutants in the effluents discharged into the Uruguay River will undoubtedly have transboundary effects in Argentina. It is nonsense to think that a supposed heterogeneous distribution of pollutants in the water (greater on the Uruguayan side than on the Argentine coast) will affect only Uruguay: chemically and biologically, the river is a single entity. What happens on one shore will affect the other in the same way.
Regarding the pollutants emitted into the atmosphere, there are three well-defined fractions. An important part will be deposited in the river, with the results analyzed in the previous point. The deposition will be direct or indirect (sooner or later), by rain washing of the surrounding lands. The other two fractions will be deposited, one in Uruguayan territory, the other in Argentine territory. What amount will be deposited on one side and the other? Very difficult to predict, even if we have the ability to predict how surface winds will move. Would it be important that this fraction of the stack emissions remains 60% in Uruguay and 40% in Argentina?
There is still another factor to consider. Disregarded in all Uruguayan reports, those of the Botnia Fray Bentos SA firm and those of the World Bank, the particular phenomenon of the Uruguay River flowing in a South-North direction will clearly discharge many more pollutants on the vast wetlands of the Argentine coast than on the coast. Uruguayan (4), recognized as a high coast in general. The same behavior that sand and sediments have today will be repeated with pollutants, which will accompany them.
For all this, it is totally logical to affirm that all the pollutants from the plant will have almost the same or greater effect in Argentine territory than in Uruguay.
- Without a doubt, the operation of the Botnia Fray Bentos S.A. it will emit pollutants. In many cases, in relatively very high quantities and dangerous to living beings, including humans. Very high for some pollutants, due to the accumulated in Kg / year recognized by the company; very high, in other cases, due to the extreme toxicity of the pollutant in question.
- The Argentine Republic will suffer the impact of these pollutants to practically the same extent as the Republic of Uruguay.
- If we're lucky, the plant may not have serious accidents or frequent, high-impact spills. But even keeping the emission levels within the limits that they set themselves, in the medium or long term, the accumulation of pollutants in the food chain will transform the region: severe losses in quality of life; land depreciation and economic ventures; and unfortunately, also the deterioration of the health of the inhabitants of the region.
(1) Reports and Minutes of the Binational Commission, GTAN. Argentine Chancellery Website, http://www.mrecic.gov.ar/ (February 2008).
(2) Matta, E. J. Cellulose Projects of the Oriental Republic of Uruguay. Environmental Risk
Part One: Basic Aspects of Kraft Plants. Ecociencia y Naturaleza, N ° 3, p 18-23, August 2007. ISSN 1851-0620
(3) Matta, E. The Environmental Risk
Part Two: Kraft Plants, Contaminants and Pollution. Ecociencia y Naturaleza, N ° 4, p 8-15, October 2007. ISSN 1851-0620
(4) Matta, E. The Environmental Risk
Third Part: International Business and Nature. Ecociencia y Naturaleza, N ° 5, p 6-13, December 2007. ISSN 1851-0620
(5) Oriental Republic of Uruguay. Ministry of Housing, Land Management and Environment. R.M. 63/2005 of February 14, 2005. File. 2004 / 1177.http: //www.mvotma.gub.uy/dinama/index.php? Option = com_docman & Itemid = 153 (February 2008)
Annex Tables Not included
Note: Elías Jorge Matta is a Chemical Engineer, research professor at the Faculty of Chemical Engineering (FIQ) and one of the UNL specialists who advised the Argentine Foreign Ministry in the conflict over the cellulose pulp factories. Article sent by Martín Alazard