Dong Younsuk, Safferman Steven I, Ostahowski Jeff, Herold Tom, Panter Ronald
a Department of Biosystems and Agricultural Engineering , Michigan State University , East Lansing , Michigan , USA.
b Sustainable Environmental Technologies , Mount Morris , Michigan , USA.
J Environ Sci Health A Tox Hazard Subst Environ Eng. 2017 Jan 2;52(1):55-63. doi: 10.1080/10934529.2016.1229928. Epub 2016 Oct 11.
When a fast-food restaurant's wastewater containing fats, oil and grease (FOG) is discharged into a collection system, it builds up over time and clogs pipes. Similarly, when such wastewater flows into a septic soil treatment system, it adheres to the surface of inlet pipes, gravel/distribution media and soil, restricting the flow and eventually clogging the septic soil treatment system. In this study, an enzymatic pretreatment system was tested on wastewater from a fast-food restaurant to determine its effectiveness in preventing septic soil treatment system clogging. This system used aeration equipment, baffles and a one-time inoculum that excretes enzymes to reduce the molecular weight and number of double bonds associated with FOG. FOG containing triglycerides having lower molecular weights and fewer double bonds are less sticky. The enzymatic pretreatment system was found to cause these changes as verified by measuring the types of triglycerides (compounds in FOG) using liquid chromatography/mass spectrometry. A unique bench-scale septic soil treatment system (soil trench) was also used. Each contained six soil moisture sensors to enable the determination of moisture saturation trends among the five tested conditions: sanitary wastewater only, a combination of sanitary and kitchen wastewater, enzymatically pretreated sanitary and kitchen wastewater, kitchen wastewater, and enzymatically pretreated kitchen wastewater. For all influent types, a significant amount of FOG and other pollutants were removed, regardless of the initial concentrations. Moisture sensor readings showed differences among the tested conditions, indicating that septic soil treatment system clogging was delayed. Inspection of the influent pipe and gravel at the end of testing verified these differences as did the measurements of volatile solids.
当一家快餐店含有脂肪、油和油脂（FOG）的废水排放到收集系统中时，随着时间的推移，它会积聚并堵塞管道。同样，当这种废水流入化粪池土壤处理系统时，它会附着在进水管、砾石/分配介质和土壤的表面，限制水流，最终堵塞化粪池土壤处理系统。在本研究中，对一家快餐店的废水进行了酶预处理系统测试，以确定其在防止化粪池土壤处理系统堵塞方面的有效性。该系统使用曝气设备、挡板和一次性接种物，接种物会分泌酶以降低与FOG相关的分子量和双键数量。含有较低分子量和较少双键的甘油三酯的FOG粘性较小。通过使用液相色谱/质谱法测量甘油三酯（FOG中的化合物）的类型，证实酶预处理系统会导致这些变化。还使用了一个独特的实验室规模的化粪池土壤处理系统（土壤沟渠）。每个系统包含六个土壤湿度传感器，以便能够确定五种测试条件下的水分饱和趋势：仅生活污水、生活污水和厨房废水的组合、经酶预处理的生活污水和厨房废水、厨房废水以及经酶预处理的厨房废水。对于所有进水类型，无论初始浓度如何，都去除了大量的FOG和其他污染物。湿度传感器读数显示了测试条件之间的差异，表明化粪池土壤处理系统堵塞被延迟。测试结束时对进水管和砾石的检查以及挥发性固体的测量都证实了这些差异。
