Hydrothermal Processing Pilot System

Genifuel Corporation developed a pilot system to transform a mixture of 20% algae and 80% water into bio-crude oil and natural gas, licensing a technology from Pacific Northwest National Laboratory (PNNL). PNNL had proven their technology at a lab scale, but Genifuel wanted to scale the system up to process one wet ton per day (WTPD) of feed, a system 20 times bigger than what had previously been done.

Merrick provided turnkey services for the scale up, including engineering, hazard assessment, cost estimating, procurement, fabrication/assembly oversight, and commissioning. Merrick’s involvement included both front-end engineering and detailed engineering. The engineering team was comprised of process, mechanical, structural, piping design, electrical, instrumentation, commissioning, and project management.

One-of-a-Kind Features

The hydrothermal process is unique in that it is highly efficient, converting 85% of the feedstock into fuel. Also, this is a wet process, therefore, it does not waste energy drying the feedstock. Another unique feature of the system is the use of a slurry of 20% biosolids (in this case, algae) and 80% water. Dewatering of biomass, a necessary step in most other biosolids-to-fuel processes, is an energy intensive and expensive step. The Genifuel system avoids this step by processing the 80/20 slurry directly.

This was a first-of-its-kind application, so Merrick also designed skids and specified a combination of standard vendor equipment and custom-designed equipment. The system was designed to be fit into standard ISO shipping containers, allowing the skids to be easily shipped around the world. Merrick used 3D modeling to ensure that the fully equipped skids would fit into these standard containers. Merrick and the fabricator invested a significant amount of time in reviewing the 3D models and modifying layouts to accommodate the necessary equipment sizes.

An Environmentally Conscious Solution

This innovative project converts something as common as algae into fuel for your car, ultimately reducing America’s dependence on petroleum-based fuels. Although the system was designed using algae as the biomass feedstock, almost any biosolid mixed in a slurry could be used. For example, hydrocarbon rich waste from other processes such as agricultural, food processing, or wastewater systems could be turned into a usable fuel. Since no solvents or chemicals are used, there is no need to then sequester the solvent or chemical at the end of the process. The use of biomass-produced fuel causes no net increase in greenhouse gases and produces clear, sterile water as a byproduct.