Loren G. Flaugh
Navigator CO2 Ventures LLC plans to start construction on its Heartland Greenway pipeline in second-quarter 2024, with project commissioning and startup in mid-2025. Earlier this year, executive vice-president Stephen Lee briefed the O’Brien County, Iowa, board of supervisors on recent progress and developments with Navigator’s proposed Heartland Greenway carbon capture and sequestration (CCS) pipeline system. Accompanying Lee were Navigator vice president of government and public affairs Elizabeth Burns-Thompson and Valero Renewable Fuels Co.’s Hartley, Iowa, plant manager Kraig Kruger.
Just 1 week earlier, Sioux Falls, SD, based POET LLC had committed to transport 5 million tons/year (tpy) of CO2 using Navigator’s CCS pipeline. Heartland Greenway was initially proposed as a 1,300-mile, $3 billion CCS pipeline system crossing South Dakota, Nebraska, Iowa, and Minnesota, with a southeast endpoint in Illinois where CO2 will be sequestered 6,500 ft down in the Mt. Simon sandstone formation.
Navigator vice president of capital projects Chris Brown noted in a separate meeting that higher costs for both gasoline and diesel were likely to hike overall project costs beyond initial estimates given the multitude of heavy machinery that would be used both during construction and restoration.
With the addition of POET to the platform, Heartland Greenway system will provide CCS for more than 30 industrial processors across the agriculture and food production value chains, representing 10 million tpy of CO2 emissions, including the two largest bioethanol producers in the US: POET and Valero.
POET produces more than 3 billion gal/year at plants from northeastern Colorado to northwestern Ohio and northern South Dakota to central Kansas. Valero produces 1.6 billion gal/year from plants between South Dakota and Kansas to the West and southern Ohio to the East. The bulk of both companies’ plants, however, are in Iowa.
The POET effect
In light of POET’s participation, Navigator filed a request June 15 with the Iowa Utilities Board (IUB) to hold additional landowner informational meetings to those already scheduled for August 2022 in counties newly affected by potential pipeline construction.
No liquified CO2 pipelines currently operate in Iowa. When all of POET’s Iowa ethanol plants are eventually connected to Heartland Greenway, Navigator could end up building more than 900 miles of new pipeline in Iowa, Burns-Thompson reported.
She was optimistic that POET’s addition to the Navigator project would help ensure that both it and other sequestration projects would get built. “I think with POET coming on board this showcases that a predominant portion of the ethanol industry has recognized the value and potential that carbon capture has for the ethanol marketplace,” Burns-Thompson said. “We now see how much the industry has reflected on these large aggregating projects like ours, or Summit’s, or some of the others.” She went on to express her belief that a majority of the ethanol industry had either committed to self-storing (if in a geologically suitable setting) or joining an aggregating project like Heartland Greenway.
Summit Carbon Solutions LLC is proposing 706-miles of pipeline through Iowa as part of its 2,000-mile Midwest Carbon Express project. Summit expects to start construction in second-quarter 2023 to meet project commissioning in mid-2024. And an Archer-Daniels-Midland (ADM) Co.-Wolf Carbon Solutions US LLC. partnership has proposed a CCS pipeline project from Cedar Rapids, Iowa, east to an existing ADM ethanol plant and underground CO2 storage site near Decatur, Ill. ADM has been sequestering CO2 under the plant for more than 10 years.
Four of the lateral pipelines that are part of Heartland Greenway will converge at Valero’s Hartley plant, operating since 2007. A 12-in. OD lateral will come in from the southwest carrying liquified CO2 from three ethanol plants in Nebraska. An 8-in. OD lateral will carry liquified CO2 from six of POET’s South Dakota ethanol plants as well as its Ashton, Iowa, production site. Another 8-in. OD lateral will collect CO2 from two ethanol plants northeast of Hartley. And finally, a 6-in. OD pipe will run from Valero’s fermentation processing unit to the CCS site it will engineer and build at the same location.
These four CO2 streams will be aggregated into a large manifold piping assembly built at the Valero site that could encompass about 1 acre. This manifold assembly would be similar in appearance to what might be seen at any large petroleum products pipeline station. Exiting that CO2 manifold piping assembly will be a 16-in. OD pipeline headed southeast and becoming Heartland Greenway’s mainline to Illinois.
A booster pump station will be built in Story County near Des Moines, with the mainline increasing to 20-in. OD. A second booster pump station will be sited in Lee County, with the pipeline increasing to 24-in. OD before crossing the Mississippi River into Illinois. Brown said another pump station will be built in Illinois between the border and Mt. Simon. No compression will be installed on the gathering portions of the system.
The system will be able to add each new carbon-capture site as its ready, with system balancing ensuring that additions upstream or downstream of plants already sending CO2 into the pipeline won’t displace that material. Navigator will use reciprocating compressors for Heartland Greenway, with Valero using integral-geared compression for its operations.
Heartland Greenway has not yet decided whether its main control room will be in Des Moines or Dallas. But the pipeline will have multiple control rooms for redundancy, with Omaha also a possibility.
The 0.25-in. WT pipeline’s maximum allowable operating pressure will be 2,200 psig, with 8-hr hydrostatic testing under Pipeline and Hazardous Material Safety Administration supervision to 2,750 psi.
Heartland Greenway will purge and pack the system after successful completion of pre-startup review by all ethanol plant participants. Commissioning will begin from the easternmost lateral. Adjacent upstream segments will be commissioned until the entire 1,300 miles of initially proposed pipe is purged.
The system will be purged (0-30 psig) with either CO2 or N2 to remove all initial contents. It will then be vented to the atmosphere. Upon successful purge of 2-3 pipe volumes, the system will be packed to ~1,200 psig, according to Lee.
Navigator’s senior director of environmental and regulatory affairs, Monica Howard, said the company will file its hazardous liquid pipeline permit applications with the Iowa Utilities Board and the South Dakota Public Utilities Commission in October-November 2022. Navigator on July 25, 2022, filed its petition to build the 250 miles of Heartland Greenway in Illinois. Howard noted that Nebraska doesn’t have a state-level regulatory process for addressing such permit requests, with each county instead issuing individual permits. The pipeline’s Minnesota filing will occur last, with only one ethanol-capture site and a few dozen miles of pipeline currently planned near the Iowa-Minnesota border.
Loren Gaylord Flaugh is a freelance writer based in Primghar, Iowa. Previous work includes more than 12 years with Dresser Engineering, many of them spent as a power and control technician on pipelines and other petroleum sites in numerous states. Flaugh graduated (1966) from Paullina Community School in Paullina, Iowa, before enlisting in the US Navy Reserve Seabees and serving in Vietnam.