Anaerobic digestion of thin stillage for energy recovery and waste management

IGPC Bioethanol每年生产1.7亿升乙醇，沿着12万吨酒糟。 这一过程产生了34亿升高有机含量的稀酒糟。目前，薄 酒糟在使用蒸发器的能源密集型过程中浓缩，从糖浆中提取玉米油， 用于生物柴油生产，并将浓缩的糖浆添加到酒糟中。考虑到 稀釜馏物的蒸发是能量密集型的，IGPC最近开发了生产高浓度蒸馏水的能力。 不能与糖浆结合的优质蛋白质酒糟， 稀酒糟至关重要。 该项目的目标有三个方面。首先，我们的目标是减少废物中的有机污染物 玉米生物乙醇产业的流，从而减轻其不利的环境影响， 消化技术第二，由于有机废物的厌氧消化，将产生能量， 发电将用于生物乙醇生产工厂。第三个目标是循环利用污水 厌氧消化池的前端工厂，以减少所需的淡水量， 过程每升玉米乙醇的生产导致产生20升具有高浓度的乙醇的废物流。 有机污染物的水平，即稀酒糟。因此，使用 厌氧消化技术将大大提高玉米生物乙醇生产的可持续性。 鉴于地球上可用的淡水资源有限，开发一种技术， 在工厂中使用的工业废水的再循环是非常重要的。为此，主要 本计画的目的是建立厌氧折流板反应器的最佳操作条件 (ABR)这导致存在于稀酒糟中的有机污染物转化为沼气的最高生物转化率， 一种能量的来源生物反应器最佳运行条件的确定 通知工艺设计以按比例放大反应器。

IGPC Bioethanol produces 170 million litres of ethanol per year, along with 120,000 tons of distillers grains. This process results in production of 3.4 billion litres of thin stillage with high organic content. Currently, thin stillage is concentrated within an energy intensive process using evaporators, corn oil extracted from the syrup for biodiesel production and the concentrated syrup is added to the distiller's grain. Given that the process of evaporation of thin stillage is energy intensive and IGPC has recently developed the capability to produce high quality protein distiller's grain which can not be combined with the syrup, finding alternative application for thin stillage is crucial. The objective of this project is threefold. First, we aim to reduce the organic contaminants present in waste streams of corn-bioethanol industries and thus to mitigate their adverse environmental impacts using anaerobic digestion technology. Second, as a result of anaerobic digestion of organic wastes, energy will be produced for electricity generation to be used in the bioethanol production plant. The third objective is to recycle the effluent of anaerobic digester to the front end of the plant in order to reduce the amount of fresh water required in the process. Production of each liter of corn-ethanol results in generation of 20 liter of waste streams with high level of organic contaminants, namely thin stillage. Therefore, management of thin stillage waste streams using the technology of anaerobic digestion will largely improve the sustainability of corn-bioethanol production. Given that limited fresh water resources are available on earth, development of a technology that enables recycling of the industrial wastewater to be used in the plant is significantly important. To this end, the main objective of this project is to establish the optimum operation conditions of an Anaerobic Baffled Reactor (ABR) that lead to the highest bioconversion rate of organic contaminants present in thin stillage into biogas as a source of energy. Establishment of the optimum condition for the highest performance of the bioreactor informs process design for scaling up the reactor.