Journal Information
Title: Enfoque UTE
Copyright: 2023, The Authors
Abbreviated Title: Enfoque UTE
Volume: 14
Issue: 4
ISSN (electronic): 1390-6542
Copyright statement: License (open-access,
https://creativecommons.org/licenses/by/3.0/ec/):
Article Information
Date received: 10 August 2023
Date revised: 23 August 2023
Date accepted: 25 August 2023
Publication date: Oct. 2023
Publisher: Universidad UTE (Quito, Ecuador)
Pages: 1-8
DOI: https://doi.org/10.29019/enfoqueute.988
http://ingenieria.ute.edu.ec/enfoqueute/
Greenhouse Gas emissions from the Abandoned Solid Waste Final Disposal Site of the City of Veracruz, Mexico
Manuel Alberto Susunaga-Miranda1, Benigno Ortiz-Muñiz2, Bertha María Estévez-Garrido3, Rodrigo Manuel Susunaga-Estévez4, Mario Díaz-González5, Olaya Pirene Castellanos-Onorio6
Abstract
The Abandoned Sanitary Landfill of the City of Veracruz, located to the north of the municipality, was built in the year 2000 and operated according to the regulations in force at the time, for a useful life of 10 years. However, it continued its operation irregularly, collapsing and becoming a controlled final disposal site that was closed by the state environmental authorities in 2019. Through the use of Google Earth satellite images using multicriteria techniques, it was determined that it has an area of 167 228 m² and an accumulated volume of waste of 1 505 052 m³, The Mexican Biogas Model 2.0 was used to estimate the generation of biogas that until the year 2023 was a total of 2 898 064 tons of biogas and with the help of the methodology for the greenhouse effect calculation for urban solid waste. It was determined that in this same period a total of 2 522 057.3 tons of carbon dioxide, 1 162 154.8 tons of methane and 47 115.9 tons of nitrous oxide were emitted. Which represents a total of 47.5 Mt CO2 eq, which shows the importance of minimizing greenhouse gas emissions and their impact on the environment due to global warming of the atmosphere, especially in the coastal ecosystem where the municipality of Veracruz, Mexico is located.
Keywords
Remote Sensing; Mexican Model of Biogas; contaminant migration; GHG; climate change.
Resumen
El relleno sanitario abandonado en la ciudad de Veracruz, ubicado al norte del municipio, fue construido en el año 2000. Operó, para un tiempo de vida útil de 10 años, de acuerdo a la normatividad vigente en la época. Sin embargo, continuó su operación de manera irregular, colapsando y convirtiéndose en un sitio de disposición final controlado que fue clausurado por las autoridades ambientales estatales en el año 2019. Mediante el uso de imágenes satelitales de Google Earth y el uso de técnicas multicriterio se determinó que cuenta con una superficie de 167 228 m² y un volumen acumulado de residuos de 1 505 052 m³. Se utilizó el Modelo Mexicano de Biogás 2.0 para estimar la generación de Biogás, que hasta el año 2023 fue de un total de 2 898 064 toneladas de Biogás. Con la ayuda de la metodología para el cálculo de efecto invernadero por residuos sólidos urbanos se determinó que en este mismo período se emitieron un total de 2 522 057.3 toneladas de dióxido de carbono, 1 162 154.8 toneladas de metano y 47 115.9 toneladas de óxido nitroso, lo que representa un total de 47.5 Mt CO2 eq. Lo dicho evidencia la importancia de minimizar las emisiones de gases de efecto invernadero, así como su impacto al ambiente por el calentamiento global de la atmósfera, sobre todo en el ecosistema costero en el que se asienta el municipio de Veracruz, México.
Palabras Clave
Percepción remota; Modelo Mexicano de Biogás; migración de contaminantes; GEI; cambio climático.
I. Introduction
The Municipal Solid Waste (MSW), are generated in households as result of domestic and some commercial activities, and also the cleaning inside of public spaces as schools, streets, parks and gardens [1]. In México according at Ministry of Environment and Natural Resources (SEMARNAT) the waste is composed of their packages and containers of food products, food leftovers, paper, wood, cardboard and a fraction of inorganic materials such as plastic, glass and metals [2]. Worldwide almost two thirds of this heterogeneous mixture are biodegradable since they are generally composed of 50 % cellulose, 15 % lignin, 10 % hemicellulose, 5 % protein, starch, pectin and other soluble sugars whose product of anaerobic digestion generates a series of gases called biogas .
The population increase and the change in domestic activities, particularly in developing countries, has caused the generation of large volumes of waste, exceeding the capacity of municipal authorities for its proper disposal [5]. According to data and estimates from the World Bank by the year 2020, around 2 010 million tons of MWS were generated on our planet, of which it has been calculated that around 66 % of these are not managed in an environmentally safe manner, expecting that by the year 2050 the global amount of waste increases to 3 400 million tons, with a growth close to 70 % [6].
In Mexico, final disposal sites are classified depending on their operation, depending on the degree of control of municipal solid waste such as Sanitary Landfills, Controlled Disposal Sites and Uncontrolled Disposal Sites, and the technical characteristics can range from complex technological processes to avoid environmental contamination to the complete absence of infrastructure [7]. This constitutes a long-term source of contamination, since they impact the environment for years or decades after their closure, abandonment or decommissioning [8].
The final disposal sites of waste they generate and emit biogas [9], which is mainly composed of carbon dioxide (30-45 %), methane (40-65 %) and a variety of gases such as water vapor (1-5 %), hydrogen sulfide (1-3 %), nitrous oxide (1-3 %), ammonia whose emission rate is influenced by factors such as the volume of accumulated waste, organic matter content, moisture, temperature, age of the waste [10], and its stages of operation.
The final waste disposal sites contribute globally with approximately 5 % of the global generation of greenhouse gases (GHG), since these emissions that begin during the operation stages continue for many years after the closure or abandonment of the final disposal site, which represents risks to the environment and to the health of the people who inhabit their environment [9]. It has been calculated that in 2020 methane emissions from sanitary landfills and dumpsites in Mexico generated 24.67 Mt CO2 equivalent, being the second country in Latin America with the highest emission rate of this greenhouse gas from landfills [11].
The sanitary landfill of the city of Veracruz, Mexico, began its operations in 2000. It was built using environmental engineering techniques that through the use of cells with membranes, gas venting wells and leachate lagoon, which would have a useful life of 10 years. However continued in use until 2019 when was closed by the Environmental Attorney of the Government of the State of Veracruz, due to the fact that it had collapsed, covering the entire infrastructure with waste and due to frequent fires [13]. Therefore, at the end of its operation stage, it was already considered a controlled final disposal site [7].
With Geographic Information Systems (GIS) that use remote sensing techniques [14] the final disposal sites and their facilities have been georeferenced [14] and through spatial data [15] its characteristics (topography and vegetal cover) the foregoing is possible using Google Eart satellite images [16]. As Susunaga et al., in 2022 who carried out an investigation using this methodology and determined the characteristics of the uncontrolled final disposal sites of the Sotavento Region in the state of Veracruz, Mexico [13].
Greenhouse gases (GHG) are those that trap heat in the atmosphere and that generate a series of environmental impacts such as global warming and, as a consequence, climate change [7], among these gases are included carbon dioxide, methane and oxide nitrous [11]. Methane and carbon dioxide are the two most important greenhouse gases, although the lifetime of both in the atmosphere is different (12 years for CH4 and between 50 and 200 years for CO2), however the difference lies in the warming power and that methane when reacting in the atmosphere becomes CO2 and water, reinforcing the global warming potential through the greenhouse effect [17].
The emission rate of methane, carbon dioxide a nitrous oxide can be determined using the Mexican Biogas 2.0 model [11]. Which considers the amount of waste accumulated in a year, and that the composition of the gas is 40% methane and 50 % carbon dioxide and assuming that six months after the closure of the site the maximum generation occurs, which decreases as the organic matter is consumed and what occurs one year after the abandonment or closure of the final disposal site [18], and a 1.5 % of emission as nitrous oxide.
The inadequate disposal of Municipal Solid Waste in the uncontrolled abandoned final disposal sites represents an important source of contamination for the surrounding in-habitants, since remediation techniques, waste isolation or monitoring of the same are not generally included [12] [13], the aim of this work was to determine the generation rate of methane and carbon dioxide, which are the greenhouse gases with the highest proportion of biogas from the abandoned disposal site of the City of Veracruz, Mexico in order to demonstrate the importance of the adequate closure of the site to minimize the emission of greenhouse gases and their potential impact on the environment.
II. Material and methods
A. Abandoned Solid Waste Final Disposal Site of the City of Veracruz, Mexico.
The municipality of Veracruz is located in the central part of the State of Veracruz, in the Sotavento Region on the coast of the Gulf of Mexico, it has 297 km2 (0.3% of the state territory) and 607 209 inhabitants which represents 7.5 % of the state total and with the municipalities of Boca del Río, Medellín and Alvarado form as a whole the most metropolitan area in the state populated metropolitan area in the State of Veracruz with 939 046 inhabitants [19] (Fig. 1).
Fig. 1. Municipality of Veracruz, Veracruz State, Mexico.
According to the data provided by the National Institute of Statistics and Geography (INEGI), the climate in the municipality of Veracruz is type A (w2) Warm Subhumid with summer rains, with prevailing winds from the North with a speed of 2 m/sec., average temperature of 29°C and relative humidity of 75 % [19].
The Abandoned Sanitary Landfill of the city of Veracruz, was an infrastructure for the disposal of Municipal Solid Waste, closed since December 2019 by the environmental authorities of the Government of the State of Veracruz and which is located north of the municipality of Veracruz [20] in a property in commodatum of the Ex Hacienda Santa Fe of The Administration of the Veracruz National Port System (ASIPONA) at 19°13’56.98”N and 96°1 3’22.11”W (Fig. 2). In a radius of 2 kilometers, borders to the north and west with a wetland area, to the east with to the east with logistics zones and the Renacimiento, Bahía Libre and Condado Valle Dorado neighborhoods, to the southeast with the Chalchihuecan neighborhood, and to south with the Olmeca Industrial Park, and the Geovillas Los Pinos and Colinas de Santa Fe neighborhoods with a population in 2020 of 28 857 inhabitants [19], as shown in Table 1.
Table I. Population Around the Abandoned Sanitary Landfill of the City of Veracruz
Neighborhoods |
Population (2020) inhabitants |
Bahía Libre |
344 |
Renacimiento |
1780 |
Condado Valle Dorado |
673 |
Geo Villas Los Pinos |
16 855 |
Colinas de Santa Fé |
9205 |
Total |
28 857 |
|
|
Fig. 2. Abandoned Landfill of Municipality of Veracruz, Veracruz State, Mexico and its nearby neighborhoods.
B. Characteristics of the Abandoned Final Disposal Site of the City of Veracruz, Mexico using GIS tools.
The characterization of the abandoned final disposal site, their coverage area and some topographic features was carried out through of Geographic Information Systems through analysis of satellite images with the use of remote sensing techniques [14] using free-form satellite photographs from Google Earth (using available photographs from the years 2002, 2013 and 2023) with a multi-criteria decision analysis (MCDA) approach (which is an analytical technique that allows the identification of various solutions to a problem, mainly using cartographic variables as starting data.) [16], and using data available in the literature
C. Calculation of accumulated waste the Abandoned Final Disposal Site
The volume of the abandoned disposal site was determined using the formula proposed by Susunaga et al. in 2022 [13], multiplying the area determined with the satellite photographs using Google Earth with the average height that occurs in the abandoned sanitary with, the following formula we used.
Equation 1
Waste Volume = (A)(AH) (1)
Where A is the total area of Abandoned Landfill, AH is the average height of the waste resulted from tracking the cover layers using Google Earth, and to calculate the accumulated tons of waste, the average value of the established volumetric weight of 1 300 kg/m3 we used for compacted waste in Sanitary Landfills and controlled final disposal sites [13].
D. Calculation of the volume of methane, carbon dioxide and nitrous oxide based on the biogas generated in the abandoned disposal site by Mexican Model of Biogas 2.0.
For the estimation of the generation of methane and carbon dioxide from the Final Disposal Site, the equations proposed in the Mexican Biogas Model 2.0 will be used, which establishes that 40 % of the biogas produced corresponds to methane and the remaining 50 % corresponds to carbon dioxide and 3 % to nitrous oxide [11]. This method was selected since it is a calculation mechanism approved by the Mexican government in the standard NOM-083-SEMARNAT-2003 and in the project to modify the official Mexican standard NOM-083-SEMARNAT-2003 , which uses a first-order degradation equation which is described in Eq. (2).
Equation 2