A System Dynamics Approach to Evaluating Sludge Management Strategies in Vinasse Treatment: Cost-Benefit Analysis and Scenario Assessment
Agustin Olivares, Paul Leger, Rodrigo Poblete
TL;DR
This paper tackles the industrial vinasse wastewater challenge in Chile's alcohol sector by introducing a System Dynamics Model (SDM) to evaluate sludge-management strategies. The model employs a stock-flow diagram that captures vinasse and sludge accumulation, coagulant dosing, sludge transport, and ambient temperature to simulate hypothetical scenarios. It contributes a pioneering SDM for industrial sludge management and presents cost implications for three management options, calibrated with historical data from a Chilean producer. The findings offer decision-makers quantitative insights into strategies such as coagulation-flocculation, transport optimization, and capacity expansion, supporting cost-effective vinasse treatment and regulatory compliance in the pisco industry.
Abstract
In the Chilean local alcohol industry (pisco indus- try), for one liter of alcohol produced 10-15 liters of vinasse as the main wastewater of the process. To comply with industrial waste regulations, vinasse must be stored, which enables evaporation, leaving behind a residual sludge. However, treating vinasse remains an environmental and industrial challenge, having a high nutrient concentration and acidity that can degrade soil quality and harm surrounding vegetation. While previous studies have modeled sludge generation and transport in urban water systems, research on industrial wastewater, such as the alcohol industry, remains limited, affecting the search for opportunities to improve the treatment process.. This paper proposes a System Dynamics Model (SDM) to assess the costs associated with three management strategies: natural drying of vinasse, relocation to an alternative site, and implementation of a coagulation- flocculation treatment to accelerate sludge production. This paper makes two contributions. First, we describe a pioneer SDM applicable to sludge management, which includes variables such as sludge transport, coagulant quantity, and ambient temperature to make hypothetical scenarios that affect the treatment processes of vinasse. Second, we present the expected results of the associated costs of the scenarios proposed in the model, helping decision-makers to manage vinasse. The model is calibrated with historical data provided by a company in the North of Chile, helping to improve the decision-making for vinasse treatment.