Burning Sugarcane Bagasse Research Articles

Techno-economic analysis of a hybrid combined cycle applied to sugarcane plants

Hybrid combined cycles, fueled by natural gas and biomass, have been present in several power plants. As shown by different authors, it is possible to increase the overall efficiency of these plants by means of waste heat recovery from exhaust gases of gas turbines. The main disadvantage, for some cases, is the higher natural gas consumption, making some plants economically unfeasible. The present work applies the concept of a novel hybrid combined cycle (HCC), adapted for sugarcane mills, burning sugarcane bagasse and natural gas. In order to evaluate the potential of application of this concept, a new hybrid configuration, starting from an existing plant, is proposed. A thermodynamic performance study has shown an electrical efficiency improvement (from 6.8% to 17.8%) for the same amount of bagasse originally burnt, thus allowing the plant to operate throughout the year, increasing the electricity generation (from 108.9 to 323.0GWhel) as well as meeting the same steam demands for sugar and ethanol production processes. The economic evaluation, considering investments, operating expenses and plant requisites, has pointed to an internal rate of return (IRR) of 22.89%. Furthermore, this new configuration does not depend on a large natural gas consumption (gas share of 11.4%), making the plant’s economic feasibility less dependent on fluctuations of natural gas prices. Finally, a sensitivity analysis of four different hybrid plants have shown the techno-economic feasibility of hybrid combined cycles applied to sugarcane mills, including during the off-season period.

Utilization of Sugarcane Bagasse Ash with Fly Ash as Alternative Fillers in Bituminous Concrete

Most of the roads in India are paved with bituminous concrete due to its low cost initial investment with respect to cement concrete pavement. Bituminous concrete is a dense mixture of coarse aggregate, fine aggregate, fillers and bitumen as binder. It requires frequently maintenance work. Performance of bituminous concrete depends upon its density and gradation. Its density and stability can be increased by filling its very fine voids. These voids are generally filled with filler materials, like stone dust or silica fume. Fillers are very effective in stability and rut resistance properties in bituminous concrete. Sugarcane bagasse ash is waste material, which is generally disposed in open land after burning sugarcane bagasse in Sugar mills. It is a locally available material and can be utilized as a filler material. In this paper, three different bitumen concrete grade II mixes with Sugarcane bagasse ash as filler (BCSBA), with Fly ash as filler (BCFA) and with both Fly ash and Sugarcane bagasse ash (BCSBFA) were prepared at 5%, 5.5%, 6%, 6.5% and 7% bitumen content. Content of fly ash and sugarcane bagasse ash were decided as per blending requirement of bituminous concrete grade II. Performance of bituminous concrete with fly ash and sugarcane bagasse ash were tested by Marshall stability Test. The laboratory result showed that sugarcane bagasse ash can be used as filler with fly ash without significant reduction of stability of bituminous concrete. It was also found that excess addition of sugarcane bagasse ash can increase flow value. This type of study can be a solution of sugarcane bagasse ash disposal problem.

Seasonal variations of PM10 — Trace elements, PAHs and Levoglucosan: Rural sugarcane growing area versus coastal urban area in Southeastern Florida, USA. Part II: Elemental concentrations

The largest sugarcane-growing area in the United States is in South Florida. An estimated 7 million tons of dry sugarcane leafy biomass is removed from the fields before harvest by burning the leaves off the sugarcane stalks. Preharvest sugarcane leaf foliage burning is a major source of airborne particulate matter (PM), polycyclic aromatic hydrocarbons (PAHs), biogenic trace elements such as K, volatile hydrocarbons and other pollutants. In one harvesting period, approximately 22 million tons of CO2, a greenhouse gas, is released, 7 million tons from leaf foliage preharvest burning alone and 15 million tons from burning sugarcane bagasse in the sugar mills for power generation. In this study, PM10 was collected from Belle Glade, close to the sugarcane-growing area, and from Delray Beach, an urbanized area along the East Coast of Florida. The PM samples were analyzed for trace elements and close to organic compounds. To elucidate the importance of preharvest sugarcane biomass smoke emissions on air quality, 39 trace elements, 18 PAHs, and levoglucosan were selected to apportion ambient PM constituents. Al, Ca and to a great extend also Mg are the major soil-related trace elements and key markers for fugitive soil dust emissions. Similarly, sea salt aerosol blown from the Atlantic Ocean into Florida added appreciably to PM10 trace elements concentration, especially Na and Cl. Approximately half of the sea salt aerosol (PM10 -portion) by mass is removed from the atmosphere during the transport of ocean air from Delray Beach to Belle Glade. Ambient acid displacement reactions caused a substantial portion of the Cl (˜30%) to be liberated from the sea salt aerosol to the atmosphere during transport as gaseous HCl. The PAH concentrations at Belle Glade were high when the biomass combustion markers levoglucosan and K also showed the highest concentrations. This indicates that during the sugarcane harvest season, when leaf foliage is burned off just before harvest, most of the ambient PAHs associated with PM10 are indeed related to preharvest burning, harvesting machinery emissions, bagasse burning in sugarcane mills, and other related activities that consume biomass and/or fossil fuels for sugarcane harvesting and processing.

Compressive Behaviour of Concrete by Using Bagasse Ash From Sugar Mill

The materials which are useless and unwanted is called waste product and this waste product is a burden and harmful to the environment. Sugarcane bagasse ash (SCBA) is one kind of waste which can be termed as the residue left over from burning sugar cane bagasse. The utilization of this waste may be very economical and can also solve the environmental problem. Silica and alumina are the main element of SCBA which is used as a pozzolanic material. This recycling procedure of SCBA reduces environmental pollution and this is also considered the cost-effective material. In this paper, SCBA replaces the cement as a weight of 5%, 10% and 15% which is considered. After completing the compressive strength test, the result shows that the compressive strength increases when 5% cement is replaced by sugarcane bagasse ash and this is the correct replacement of cement.

English

The aquatic macrophytes removed from hydroelectric power plants, as well as boiler ash derived from burning sugarcane bagasse can provide nutrients and recover degraded soils more quickly. Thus, this study aimed to evaluate the chemical attributes of a degraded soil in recovery process with mechanical preparation, with or without addition of organic residue (aquatic macrophytes) or agroindustrial residue (ash from sugarcane bagasse), compared to a degraded area without interference  in the time of soil removal and in a conserved Cerrado area. The experimental design was a randomized block with four replications. The treatments were: conserved Cerrado soil (T1), area of degraded soil without human intervention since their degradation (T2), soil with mechanized preparation without addition of residue (T3), soil with mechanized preparation and addition of 32 Mg ha-1 of organic residue (T4), soil with mechanical preparation and addition of 45 Mg ha-1 of agroindustrial residue (T5). The orthogonal contrasts analyzed were C1 [(T2+T3+T4+T5)/4 -T1], C2 [(T2+T3) - (T4+T5)], C3 [(T2) -(T3)] and C4 [(T4) - (T5)]. In general, the chemical attributes of degraded soil increased after the incorporation of organic and agroindustrial residue, which is higher than the soil of the conserved Cerrado area. The boiler ash contributed most, to increase the nutrient content and fertility of the degraded soil.   Key words: Aquatic macrophytes, ash from sugarcane bagasse, degraded soil, fertility, soil tillage.

Sugarcane bagasse ash sand (SBAS): Brazilian agroindustrial by-product for use in mortar

SBAS (sugarcane bagasse ash sand) is the term used for the residue left over from burning sugarcane bagasse. Large amounts of this agro-industrial by-product are generated in Brazilian sugar and ethanol plants, and its disposal is an environmental problem. The application of SBAS as a fine aggregate in mortars can add value to this waste and also reduce the use of natural sand. The growing need to extract natural sand from Brazilian rivers has caused environmental problems. In this article, the effect of SBAS on mortars was investigated, specifically its compressive strength, porosity, carbonation depth and chloride penetration. The present study fills the gap in knowledge on the durability of mortars using different levels of SBAS. The substitution of natural sand by SBAS, especially with content of 30%, can lead to maintenance of mechanical properties, micropore clogging and improvement of the durability of mortars, in comparison with a reference mixture.

Performance of mortars produced with the incorporation of sugar cane bagasse ash

This paper presents the technical feasibility of using ash in mortars, from burning sugarcane bagasse, to generate power as a mineral admixture. The sugarcane bagasse ash (SCBA) underwent chemical characterization and x-ray diffraction tests. The milling of the material was studied, together with the composition of the mortars containing the SCBA at 3%, 5%, 8% and 10% ratios by weight, as partial replacement of fine aggregates. The mechanical properties were studied by compressive and diametral tensile strength tests. Some properties related to the durability of the material were also studied, such as drying shrinkage, capillary absorption and accelerated reactivity. The work was performed using low pozzolanic activity SCBA. However, the results indicate that it is possible to use SCBA as partial replacement of fine aggregates in the production of mortars. Rev. ing. constr. [online]. 2014, vol.29, n.2, pp. 187-199. ISSN 0718-5073. http://dx.doi.org/10.4067/S0718-50732014000200005

Comparative analysis of electricity cogeneration scenarios in sugarcane production by LCA

Purpose The decentralization of the Brazilian electricity sector in association with the internal electricity supply crisis has encouraged companies in the sugarcane industry to produce electricity by burning sugarcane bagasse in cogeneration plants. This approach reduces the environmental impact of the sugarcane production and has opened up opportunities for distilleries and annex plants to increase their product portfolios. Potential scenarios for technically and environmentally improving the cogeneration performance were analyzed by using thermodynamic analysis and Life Cycle Assessment (LCA).

Operation Analysis and Thermoeconomic Evaluation of a Cogeneration Power Plant Operating as a Self-Generator in the Ecuadorian Electrical Market and Sugar Industry

This study evaluates the integral use of the sugarcane bagasse on the productive process of a cogeneration power plant in an Ecuadorian Sugar Company. Thermoelectric power plants burning biomass require a large initial investment and, for example, this initial investment requires $800/kW, which is double the initial investment of a conventional thermoelectric power plant that is $400/kW, and almost similar to the initial cost of a hydroelectric power plant that is $1000/kW. A thermoeconomic study was made on the production of electricity and the sales of the exceeding 27 MW average. From the results, it was concluded that generated electricity costs are $0.0443/kW h, in comparison with the costs of the supplied electricity through fossil power plants with values in the range $0.03–$0.15/kW h and hydroelectric power plants with a value of about $0.02/kW h. Cogeneration power plants burning sugarcane bagasse could contribute to the mitigation of climatic change. This specific case study shows the reduction of the prospective emissions of greenhouse effect gases in the amount of 55,188 ton of CO2 equivalent per year.

Flexibility and uncertainty in agribusiness projects: investing in a cogeneration plant

Energy generation from biomass has become a source of increasing interest due to growing environmental concerns and the depletion of the world's fossil fuel reserves. In this paper we analyze a sugar and ethanol producing plant in Brazil which has both the option to expand and to add a cogeneration unit to allow the sale of surplus energy, generated by burning sugar cane bagasse, where the existence of the second option is conditional to the exercise of the first option. We model sugar, ethanol, and electricity prices as geometric mean reverting processes and apply the real options approach to determine the value of these managerial flexibilities, considering that these options have three distinct underlying assets. The option to expand production is a function of the expected future prices of sugar and ethanol, while, on the other hand, the decision to invest in the cogeneration plant will depend on the future prices of energy. Both decisions are modeled as American Compound Options over their respective underlying assets. The model is then solved using the non-censored binomial mean reverting lattice proposed by Bastian-Pinto, Brandão, and Hahn (2010) using the software DPL TM. The results indicate that a significant value can be derived from the flexibility to choose the optimal timing of investment in both options: the investment in the cogeneration unit adds an amount equivalent to the value of the expanding sugar and ethanol production, and represents up to 44% of the project's static NPV of R$ 195.9 million. We conclude that given that only half of the sugar cane crushing mills currently have cogeneration units installed and given the increasing demand for clean and renewable sources of energy, this may indicate there is a significant potential for investment and further development of bioelectricity cogeneration power plants, and even in the retrofit of older cogeneration units, and that government incentives have been effective in contributing to this development.