Carbon dioxide assisted paraffinic froth treatment: Simulating flue gas

我们最近完成了NSERC CRD项目CRDPJ 516469 -17“CO2辅助石蜡泡沫处理”。在该项目中，我们将正庚烷与沥青以1.08的重量比混合，并观察到沥青质开始沉淀。随后，我们在21ºC或90ºC的该比例下将CO2气体注入庚烷/沥青混合物，并且CO2压力高达1.7 MPa，并且发现沉淀的沥青质的量显著增加。当向庚烷/沥青混合物中加入水，然后注入CO2时，甚至有更多的沥青质沉淀。总的来说，在庚烷/沥青比为1.08时，通过组合使用水和1.7 MPa CO2，沉淀的沥青质的量增加了7个百分点。因此，通过在石蜡泡沫处理中使用气态CO2可以实现溶剂剂量的显著减少。目前的提案是第二阶段研究的延续。在第2阶段，我们建议检查在烟道气中使用CO2以促进石蜡泡沫处理中的沥青质沉淀的操作参数。此外，将使用戊烷代替庚烷。烟气中的CO2含量范围为10 - 70体积%，这将在实验室中通过CO2/N2气体混合物来模拟。将使用来自König的沥青泡沫样品（已经含水）。CO2/N2混合物将在不同戊烷/沥青比下注入到戊烷/碳酸钾沥青泡沫样品的混合物中，总压力高达1.7 MPa。将确定沉淀的沥青质的量，并分析沥青产品（稀沥青）和沉淀的废物的质量。拟议项目的结果将使二氧化碳辅助石蜡泡沫处理的概念更接近于潜在的商业实施，以减少溶剂用量。

We recently completed an NSERC CRD project CRDPJ516469-17 "CO2-Assisted Paraffinic Froth Treatment". In the project, we mixed n-heptane with bitumen at a weight ratio of 1.08, and observed that asphaltene started to precipitate. Subsequently, we injected CO2 gas to the heptane/bitumen mixture at this ratio, 21ºC or 90ºC, and CO2 pressures up to 1.7 MPa, and found that the amount of precipitated asphaltene was increased significantly. When water was added to the heptane/bitumen mixture, followed by CO2 injection, even more asphaltene was precipitated. Overall the amount of precipitated asphaltene increased by 7 percentage points by the combined use of water and 1.7 MPa CO2 at heptane/bitumen ratio of 1.08. Therefore, significant reductions in solvent dosages may be achieved by using gaseous CO2 in paraffinic froth treatment. The current proposal is a continuation of the research into Phase 2. In Phase 2, we propose to examine operational parameters of using CO2 in flue gas to promote asphaltene precipitation in paraffinic froth treatment. Also, pentane will be used instead of heptane. CO2 content in flue gas ranges from 10 to 70 vol%, which will be simulated by CO2/N2 gas mixtures in the laboratories. A bitumen froth sample from Kearl will be used (which already contains water). The CO2/N2 mixtures will be injected to the mixtures of pentane/Kearl bitumen froth sample up to 1.7 MPa total pressure at different pentane/bitumen ratios. The amount of precipitated asphaltene will be determined, and the quality of the bitumen product (dilbit) and precipitated wastes will be analyzed. The results of the proposed project will bring the concept of CO2-assisted paraffinic froth treatment a step closer to potential commercial implementation for solvent dosage reduction.