The primary objective of this project is to develop and test a novel process for production of high-value carbon from the pyrolysis of uneconomical wellhead natural gas through graphitization of virgin pyrolysis carbon, or the precipitation of graphite from a carbon-saturated molten metal solution.

The carbons will be analyzed for their application to specific end-use markets. This will be followed by demonstrating a bench-scale (10 g of carbon per batch) carbon-upgrading reactor that can produce carbon at the specified market properties. In the final phase, the project will develop a laboratory-scale prototype capable of producing up to 1 kg/day of upgraded carbon.

Palo Alto Research Center (PARC) — Palo Alto, CA 94304

Partnering Organizations:
University of California, Riverside — Riverside, CA 92521
Susteon, Inc. — Durham, NC 99502
Modular Chemical, Inc. — Anchorage, AK 99502
Phillips 66 Research Center — Bartlesville, OK 74003
Civitas Resources, Inc. — Denver, CO 80202
 

The inherent compositional variability, intermittency, and distributed nature of flared natural gas poses a significant challenge to bringing it to market. Consequently, approximately 1% of annual gas production is flared or vented (an average of 645,000 cubic feet per day (Mcfd) in 2017), corresponding to a loss of nearly $1B in potential annual revenue.

Growing concerns over the environmental impact of natural gas flaring and venting has motivated efforts to utilize this gas for onsite electricity generation, modular natural gas liquids recovery, and small modular natural gas liquefaction. However, these approaches have struggled to be cost-effective at a size sufficiently small to address natural gas flares. A typical oil and gas site flaring rate is on the order of 10–1,000 Mcfd and has a corresponding annual value of $10k–$1M, making economical solutions a significant challenge.

The fundamental issue with transporting natural gas to market is its low density — or more specifically its low value density ($/m3). The transportability of any product to market is determined by its value per unit volume. To monetize flared natural gas, it needs to be converted into a much higher value density product.

In the initial phase of the project, a process for the production of carbon fiber from pyrolysis carbon will be investigated for feasibility. A technique called micro-pulldown will be adapted to pull single crystal fibers from carbon-saturated molten nickel. The fundamentals of the process will be investigated, such as rate of production, single fiber properties, materials of construction, temperature gradients, and molten nickel-carbon properties. If the feasibility assessment is successful, a micro-pulldown reactor will be procured and adapted for the process.

In the second phase of the project, an experimental proof-of-concept reactor will be developed which is able to produce graphitic carbon from pyrolysis carbon. The carbon coming out of the reactor will be measured for material properties such as crystallinity, purity, and crystal size—all properties important to the commercial viability of synthetic graphite production. Additionally, the pyrolysis reactor which will produce the carbon from the wellhead gas will be tailored from the recipient’s novel pyrolysis reactor technology to focus on the production of on-purpose carbon at as low of a price-of-production as possible.

In the project's final phase, a prototype bench-scale reactor will be designed, commissioned, and operated. This reactor will be capable of producing upgraded carbon product at a rate of 1 kg/hour from a pyrolysis carbon precursor. The properties of the carbon product will be investigated for specific market applications, potentially as a high-performance lithium-ion battery anode.

The proposed research represents a potential high-risk, high-reward solution to issues related to the production of high-grade graphite, with possible impacts on energy, the environment, and markets. Upstream, the proposed technology offers the potential to provide an economically attractive alternative to natural gas flaring, helping to mitigate substantial quantities of CO2 emissions. Downstream, this process could disrupt synthetic graphite markets, through the production of a low-cost synthetic graphite that are increasing in demand due to lithium-ion battery and graphite electrode markets.

• Established collaboration with both an upstream company that flares gas (Civitas Resources, a carbon-neutral oil and gas extractor), and a downstream company (Phillips 66, a refiner and world’s largest needle coke producer) that will be an off-taker for the carbons being produced.
• Successfully identified an achievable strategy that involves producing high-quality graphite from the pyrolysis carbon being produced from the flared gas.
• Demonstrated lab-scale production of carbon via methane pyrolysis.
• Demonstrated proof-of-concept production high-value carbon from amorphous carbon.

The project team has successfully determined a revised strategy focusing the project on the production of high-quality graphite as opposed to carbon fiber (original project intent).

PARC’s pyrolysis process will produce solid carbon from flared gas. Carbon will then be moved to a central facility for upgrading to a higher value carbon, such as graphite. Carbon powder being produced by a lab-scale experimental pyrolysis reactor will be characterized for key characteristics to determine potential end-use markets. Phillips 66 will help evaluate the carbon quality as it pertains to the battery anode and graphite electrodes markets.
 

$2,689,889

$672,472

NETL – Dave Cercone (david.cercone@netl.doe.gov)

PARC – Brad Rupp (brupp@parc.com)