An exploratory investigation of organic solid waste for energy use in the Dominican Republic: Case of the Municipality of Puñal, Santiago

One of the biggest problems that the Dominican Republic has had in recent decades is 1 the efficient management of solid waste produced by the population. This problem has worsened 2 in recent years due to the decrease in available areas for the construction of sanitary landfills, the 3 lack of recycling culture in the population, the deficiency in waste collection, and the scarce legal 4 controls aimed at preserving water and air and soil, among other factors. The objective of this study 5 was to explore the management of solid waste by the population and the municipality of Puñal, 6 province of Santiago, to evaluate and analyze the situation and generation of solid waste, municipal 7 solid waste management services, and the attitudes of the population regarding recycling projects 8 and waste management, to evaluate the viability and sustainability of the use organic waste for 9 energy generation. A total of 275 households from 29 localities in the municipality of Puñal were 10 surveyed, which allowed for a significant population sample. According to the results obtained, 11 the most significant type of waste produced by families is organic waste, followed by plastic 12 waste and paper. Of the total organic waste produced in the municipality, 53% of solid waste is 13 disregarded through the municipal waste collection system, while 47% is used as plant fertilizers 14 or animal feed. On the other hand, most households receive the municipal waste collection service 15 and pay for this service. The results of our research show that the implementation of an energy 16 production system based on organic waste would be viable in the municipality of Puñal. However, 17 a more efficient waste collection system would be necessary and the development of programs 18 and projects that allow all households to participate in the system. 19


22
The generation of solid waste in the Dominican Republic is considered a significant  In general terms, the problem described above is particularly relevant when con-58 sidering that population growth and economic development in recent decades have 59 led to an exponential increase in waste in different country areas. This increase has 60 further complicated the steps and mechanisms that must be established to implement 61 an efficient process between waste generation, its collection, and final disposal [5]. The 62 complexity of this first stage of the treatment process of solid waste generated by Domini- 63 can households has been highlighted in the National Multipurpose Household Survey

64
[6]. According to their data, 85.2% of households dispose of their solid waste through the collection mechanisms of the municipalities, 7.5% burn it, and 3.5% throw them 66 in the yard, lot, or nearby streets. These last two incorrect forms of disposal are used 67 by 11.0% of Dominican households [6]. Regarding the waste compositions produced, 68 60% is organic matter; 10% cardboard; 6% paper, plastic, and glass; 4% of metals. Other 69 unidentified materials represent 8% [1,2].

70
In addition to the damage to the environment, as mentioned before, and the expo-71 nential health risk that those practices cause, the incorrect handling of solid waste limits 72 the possibilities offered by some of the generated waste, especially the organic waste, 73 which could be used in the process of energy generation through the biogas producing 74 biodigesters, by anaerobic digestion of organic matter. Furthermore, this process yields 75 other by-products such as biol and biosol. The former is a valuable complex psychostim-76 ulant fertilizer, rich in essential nutrients for plants growth and development, and its 77 application to crops substantially improves their quality and production [7-9]. Biosol is 78 a biodigester output effluent that, when used in plantations, significantly influences the      The calculation of the sample was carried out with the following equation: where, SS sample size; z confidence level (z-score equal to 1.96 for a 95% confidence  pleted less than high school education, followed by 18% with a high school diploma,

187
15% with a university degree, and 12% with some college but no degree, only 3% of the 188 respondents had no formal education, and 10% did not report their level of education.   where it is observed that in 74% of the households, waste is collected once a week, while 221 8% collect it daily. In 13% of the households, the collection service is performed twice 222 week, while another 4% of the respondents stated that waste is collected every other day.    Regarding the sources of garbage and landfills generated in the communities, 47% 244 of those interviewed stated that it is due to the lack of waste collection. In contrast, 27% 245 indicated that it is due to deficiencies in waste collection, and 10% stated that it is due to 246 the lack of education of the inhabitants of the municipality, and 8% to thedeficiency in 247 the design of the waste collection routes (Supplementary Figure 4).  the production of quality biogas for industrial use.

279
Several companies have implemented biodigesters to produce biogas thus reuse the 280 waste produced by their economic activity. One of these cases is that of Agropecuaria

281
Fernández Muñoz SRL (AGROFEM), which has two biodigesters, which have enabled 282 it to produce 70% of the energy needed for its farms from the excrement of its animals, 283 allowing this company to reduce its dependence on fossil fuels, which ranslates into a 284 reduction in its carbon footprint.

285
According to the study conducted by Cuervo and collaborators, the generation   Despite the deficiencies in waste management in the municipality, it has the neces-296 sary capacities to develop biogas production systems and efficient energy generation 297 that make it possible to reuse the waste generated by its citizens. The municipality 298 and other governmental entities should develop education and incentive programs that 299 encourage citizens to revalue the waste at source to achieve this objective.

300
The reuse of organic waste can become an excellent opportunity for companies to 301 reduce their environmental impact and generate the energy necessary for its production,