Technology

CASCADE

We use an In Silico screening platform called “Computer-Assisted Strain Construction and Development Engineering (CASCADE)” to systematically select organisms in respect to different wastewaters. By applying CASCADE, our product is able to link massive genetic and chemical fingerprints in the metabolic and energy-generating biological pathways to assess an organism’s metabolic capability to digest the organic matters and generate electricity, and at the same time to clean the wastewater.  This makes it possible to customize and find efficient microbes (or even to discover novel microorganisms) for electricity generation and biochemical oxygen demand (BOD) reduction based on the initial content of a wastewater. This drastically increases the conversion rates of both hydrogen and electricity productions. CASCADE selects the optimal bacteria consortia to maximize the yields of the desired renewable energy products.

CASCADE was developed in January 2007.  We are currently running four real-life tests of selection microorganisms for their metabolic advantages. The CASCADE technology is undergoing validation at ARL/ARO for MFC, University of Wyoming for spider silk production and Georgetown University for pathogen detection. For a given organism, a given content of a bio-waste input and a desired clean energy output, we first compile a profile for that organism. For example, data and text that describes a biological system as a whole can be collected including information on gene similarity among organisms, gene functions, metabolic functions, biological pathways and pathway substrates/products involving energy-generation. This is done for the organisms in various public and private databases. We then apply a network of Knowledge Pattern Search to group the organism population into characteristic groups based on the profiles compiled previously. One or a group of microorganisms are selected based on a profile match score. The score is calculated for each organism from a defined metabolic efficiency measure for the organism. A metabolic efficiency measure is a prediction of a desired capability in real life based on an organism’s profile. 

CASCADE Methane

As opposed to the aerobic systems used in most WWTF today, CASCADE Methane utilizes an anaerobic digestion process for organic material decomposition without oxygen. The dark fermentation process of anaerobic respiration produces hydrogen and methane (CH₄) and other greenhouse gases such as carbon dioxide (CO­₂). Anaerobic systems require much less electricity than the aerobic system. The annual power usage of a single residential system is in the range of 50 to 100 kWh (7% of an aerobic system) and requires no air supply.

Methanogenic anaerobic digestion is installed in 1% of WWTF. According to the Lawrence Berkeley Lab’s report, the most widely used technology for methaogenic anaerobic wastewater treatment is the Upflow Anaerobic Sludge Blanket (UASB) reactor, which was developed in 1980 in The Netherlands for use predominantly in the paper and food industries, but some industries such as chemical and pharmaceuticals also use this technology. Globally, there are approximately 1500 anaerobic wastewater treatment plants (80 percent are UASBs), of which approximately 150 are in the U.S.

CASCADE Microbial Fuel Cell (MFC)

Microbial Fuel Cell (MFC) technology utilizes bacteria to produce electricity in what is referred to as the MFCs are a novel method of renewable energy recovery; electricity can be made from any biodegradable material, even wastewater, without needing to add special chemicals. Historically, MFCs did not produce electricity economically.

Applying CASCADE makes it possible to customize and find efficient microbes for electricity generation and BOD reduction based on the content of a wastewater.  For example, we compiled number of substrates consumed and products produced in the reactions involved in a fermentation process which uses a biowaste input as the feeding substrates. Using CASCADE, we include the combined information of substrates (In), products (Out), metabolic pathways (Pathway) and interested properties (Target) such as electrogenic results in a list of microorganisms that are likely taking cellulose or actetate as a substrate reflecting in the various wastewater contents. It provides a fast path to find the microorganisms that are able to digest diversified waste contents and recover clean electricity.