Expertise: Carbon Capture

Summary

In the rapidly evolving landscape of sustainability and carbon reduction, staying ahead of the curve is crucial. CANUSA EPC has curated a list of 2026 carbon-related events, conferences, and tradeshows across Canada & the USA.

Each event has been selected for its networking opportunities, panels of leading experts, and discovering cutting-edge solutions. Whether you’re a seasoned professional or just beginning your journey in the field of carbon reduction, this e-book will help you determine which event(s) you may want to attend this year. Download now and let the team at CANUSA EPC know which ones you’re attending!

This carbon-related conferences guide includes:

• 9 events across Canada & USA
• Event Summaries
• Direct Links to Agendas

Summary

Download the presentation from CANUSA EPC’s 2025 Carbon Capture and Injection Update – Market Developments. The conference incorporated new regulations, supply chain uses for CO2, and technology development for new separation processes.

Our presentation provided insights to the follow CO2 injection trend:

• Saturated CO2 processing
• Cost models for CO2 injection
• Execution strategies for commercial success
• Future drivers of CO2 injection project

Introduction

In January 2026, the U.S. Environmental Protection Agency finalized long-awaited updates to the New Source Performance Standards (NSPS) for stationary combustion turbines—marking the first major revision since 2006. With power generation developers increasingly dependent on flexible, rapid-deployment solutions such as temporary turbines and trailer-mounted generation, these changes bring important implications for project scheduling, emissions compliance, and technology selection.

This blog outlines what has changed, how the new temporary turbine subcategory works, and what developers should consider as they plan new installations or short-term power solutions.

Updated NOx Standards for Modern Turbines

The EPA’s final rule restructures emissions requirements by grouping turbines into subcategories based on:

• Heat input (MMBtu/hr)
• Thermal efficiency (≥38% or <38%)
• Expected utilization (12-month capacity factor)
• Fuel type and load conditions

The changes align emissions expectations with what modern combustion controls and SCR technology can realistically achieve.

Key NOx Standard Revisions

• Large, high-utilization turbines (>850 MMBtu/hr, >45% CF) must now meet single-digit NOx emissions using combustion controls + SCR.
• Medium and small turbines retain combustion-controls-only pathways with updated ppm limits.
• Natural gas remains the basis for hourly emissions performance.
• SO₂ standards remain unchanged, with more flexible compliance options.

For developers, these updates will influence technology specifications, EPC execution planning, and permitting timelines.

The New Temporary Turbine Subcategory

The 2026 rule introduces a dedicated regulatory framework for stationary temporary combustion turbines, addressing an industry need for short-term, flexible power during outages, commissioning, construction sequencing, or emergency support.

Key Features of the Temporary Turbine Category

• Applies to turbines up to 850 MMBtu/hr
• Limited to 24 months at a given location
• NOx standard: 25 ppm using combustion controls only
• Reduced monitoring and recordkeeping
• Exempts certain portable Title II-covered engines
• Prevents “serial swapping” to extend temporary status

This category enables faster, more efficient deployment of turbine temporary power and trailer-mounted power generation systems—without excessive compliance burden.

MW Output Estimates Based on EPA Heat Input Categories

Because EPA regulates turbines by heat input (MMBtu/hr), developers often need a practical translation into MW output. Using typical turbine thermal efficiencies, here is a rough guide:

Turbine Category	Heat Input	Efficiency	Approx. MW Output
Large	>850 MMBtu/hr	≥38%	~95 MW
Medium	50–850 MMBtu/hr	≥38%	5–95 MW
Small	≤50 MMBtu/hr	30–38%	4–6 MW
Temporary Turbines	≤850 MMBtu/hr	30–38%	5–95 MW

These estimates help developers size temporary solutions and anticipate the emissions requirements tied to turbine selection.

Economic and Project Delivery Implications

According to EPA’s Economic Impact Analysis, the updated rule is expected to:

• Reduce annual NOx emissions by up to 296 tons by 2032
• Save industry up to $87 million over eight years
• Focus SCR deployment only on large, high-duty units where it is cost-justified

For developers, this results in:

• Lower capital costs for many turbine classes
• Continued viability of non-SCR combustion turbines
• Streamlined permitting for temporary deployments
• Enhanced flexibility in project scheduling and outage planning

The regulatory environment now better supports short-term and contingency power solutions.

What Developers and Turbine Representatives Should Do Now

1. Assess Turbine Classification Early
Efficiency, utilization, and heat input now directly determine regulatory requirements.

2. Factor in Temporary Power Strategy
Temporary turbines provide cost-effective coverage for outages, interconnection delays, and commissioning.

3. Coordinate with OEMs and EPC Partners
Thermal efficiency thresholds and NOx limits influence model selection and long-term operating strategy.

4. Review Documentation Requirements
Temporary status requires manufacturer certification and periodic (five-year) testing records.

Conclusion

The EPA’s updated NOx standards significantly modernize the emissions landscape for new and modified turbines. For developers and OEM representatives, the changes reinforce the need to plan turbine selection and temporary power strategies early in the project lifecycle. With the introduction of the temporary turbine subcategory, the industry gains a more flexible, streamlined path for meeting both short-term and long-term power generation needs.

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If you need support navigating the new NOx standards, evaluating turbine options, or planning temporary generation during outages and construction, our team is here to help you develop a compliant and cost-effective strategy.

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Author(s)

Marc Collins

At one of our recent ethanol projects, we were tasked with developing a relief solution for a dense-phase CO2 system. Like most early-stage sequestration sites in the U.S., this one had no simple way to recycle or offload off-spec product during a process upset. When working with dense-phase CO2, roughly 300 psi and as cold as -15°F, you’re dealing with a unique beast. It’s cold, high-pressure, and doesn’t behave like most fluids in a natural gas processing plant.

If the transport offtake shuts in or the CO2 goes off spec, the challenge becomes: how do you relieve this safely? What makes it especially challenging is how rapidly it changes states under relief conditions. This phase change can cause various operational issues and presents a massive safety hazard. API STD 521 is considered the bible, but this was one of those times when we had to look beyond the basic code.

Problems with Relieving Dense-Phase CO2

Safe operational design of CO2 capture facilities requires relief designs for dense-phase CO2 through a PSV.  Relieving the CO2 liquid will induce a pressure drop and phase change, dramatically reducing the temperature during the relief. As the liquid expands, it pulls heat from its surroundings and transforms into a solid, sublimation effect. Dry ice begins to form at around -130°F. Relief temperatures can dip even lower, closer to -180°F. At these temperatures, you’re almost guaranteed to get solids that can:

• Clog or choke the relief device,
• Reduce flow capacity, or
• Completely block the path to relief.

A blocked relief device means the vessel is no longer protected. Leaving you with a serious safety issue. As more CO2 capture and processing facilities are constructed, the normal approaches for relieving unsafe conditions won’t work for CO2. This requires that we develop solutions that protect the equipment while leveraging best practices from the industry.

Code API STD 521 and Solid CO2 Plugging Risks

API STD 521: Guide for Pressure-relieving and Depressuring Systems is the go-to standard for pressure-relieving systems, as it acknowledges this flash freezing issue. Section 4.9.2 touches on “Liquid-Vapor Mixture and Solids Formation” and warns about the potential for flashing fluids to cause choking or blockages. It also cites wet propane as an example of a fluid that can form solids.

However, there’s an issue. API STD 521 states that “some fluids (e.g. carbon dioxide and wet propane) can form solids when they are discharged through the relieving device. No uniformly accepted method has been established for reducing the possibility of plugging”.

There’s no established method to reliably predict or mitigate plugging caused by solid CO2 formation. It tells you the hazard exists but leaves the solution up to you. This was the biggest gap we have found and had to address in the design of our CO2 capture facilities.

An Approach to Pressure Relief for CO2 Processing: “Burping” CO2 Safely

We started with a question: What’s the safest way to handle relief of pressure for dense-phase CO2 that can’t be recycled or sent down the line?

One solution we have designed in our processing facilities for CO2 is to block and hold the system and send large volumes of the dense phase liquid to the distillation column through control valves that trigger based on plant upsets. The column is capable of holding large volumes of CO2 and any amount that vaporizes while being held can naturally vent through the overhead vent.

Thermal relief valves (TRV’s) are used to protect any equipment and piping that can possibly be isolated by check valves and can’t be sent to the distillation column during a block and hold scenario. While a pipeline is shut in, and if the pipeline is exposed to a heat source, such as heat from solar radiation or even ambient conditions during hot summer months, the internal process material will also heat up, expand, and increase pressure. In this case, the CO2 is at the bubble point and can vaporize with heat exposure. If thermal expansion occurs, these TRV’s will relieve this isolated high-pressure vapor, and prevent over pressurization of the system. Once the vapor is relieved, the TRV will reseat, and not allow further relieving.

This constant relieving and reseating, or “burping” of warm, vaporized CO2 will reduce the risk of relieving dense phase CO2. This approach avoided the extreme phase change that commonly resulted in dry ice plugs.

The Trading Off to Venting CO2: Safety vs. Speed

Burping CO2 is a potentially time-consuming process. The maximum amount of dense phase CO2 possible is sent to the distillation column. However, this CO2 still has to vaporize naturally. The CO2 is condensed at bubble point temperature, so the delta temperature it has to overcome is relatively small, allowing the CO2 to vaporize in a relatively reasonable amount of time. The phase change, however, still imposes temperature issues due to the Joules-Thomson effect, and still has risk of plugging up the vent piping. Careful pressure monitoring of this vent is implemented to mitigate this risk.

The remaining CO2 to be relieved by the thermal relief valves will naturally reset once vaporized CO2 is relieved, naturally mitigating the risk of freezing and plugging. Considering the size of a plant, this can quickly take a long time to relieve an entire process. At CANUSA, we believe that this careful vapor relief vs. the prevention of piping freezing and plugging method is the safest known relief strategy for dense-phase CO2 if no recycle solution is available.

CO2, unlike the relief of natural gas, is heavier than air and will sink or collect in low-lying areas.  Therefore, venting locations need to be considered for safe release to ensure that de-oxygenated zones don’t form and there is adequate dispersion. Typical solutions include a vent pipe from the CO2 relief valves to higher elevations to allow the CO2 to disperse.  A slower release using the Burping method will release smaller amounts of CO2 over a longer period, reducing the risk the accumulation to unsafe concentrations. OSHA incidents for CO2 handling indicate how important dissipation considerations are for the safe operations of these facilities.

Considering Process Solutions to Reduce CO2 Venting

Reducing the scenarios of release to the atmosphere not only increases the safety of the operations, but less vented CO2 will also contribute to higher capture rates and more revenue.

To reduce the scenarios of vented CO2, recycle designs can be incorporated into the process. For some facilities, a recycling approach using a closed-loop system via a cooler and blower can reduce the need to vent altogether.

This isn’t always economical. Controlled heating of dense-phase CO2 to transition to a gas phase takes considerable energy. The CAPEX of this type of system is often cost prohibitive for the low increase in recapture rate, but it could mean a true 100% capture operation.

Engineering Safety into CO2 Capture Facilities

This project made one thing very clear: the CO2 sequestration industry is evolving quickly, but the standards aren’t updating at the same speed.

We’re seeing more clients face similar problems – like what to do when a process upset sends off-spec CO2 surging through the system? API STD 521 offers the “what,” but not the “how”. Safety is vital; so, sharing solutions for the “how” is important.

Our client for this carbon capture project required:

1. Thoughtful engineering to manage dense phase CO2 during upsets
2. Minimal contamination of dense phase CO2 product – less than 10 ppm O2 in product
3. Limited venting to the atmosphere

Our team developed a practical, field-ready solution. It’s not fast. But it satisfied all of our clients’ requirements and was the safest design.

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HAVE INSIGHT ON THIS?

If you have experienced this or want to weigh in with your insights, please join the conversation on LinkedIn. Visit this post and see what others have to say!

Author(s)

Nick Brown | Project Engineer

 

External Sources:

https://www.apiwebstore.org/standards/521

https://www.osha.gov/publications/hib19960605

 

 

 

 

 

 

 

 

Summary

The CO2 market is developing rapidly based on regulations, annual governmental commitments, and voluntary carbon markets. Start to understand the CO2 market from an industrial perspective and understand concepts of Co2 sources, capture technology, and marketing of CO2.

• Sources: Point Sources, Flue Gas, Production Gas, Atmosphere
• CO2 Emissions Trends
• CO2 Capture Types – detailed explanation & notes on improvements
• How to Market CO2 – EOR, Sequestration, Liquefaction, Pipelines

Summary

Download the presentation from CANUSA EPC’s Carbon Capture Feasibility From Compressor Exhaust Streams Conference Knowledge Bar. Content includes:

• Methane sources
• Quantifying the application
• Carbon capture technology options (Metal Organic Framework & Membrane Technology)
• Carbon capture execution
• How to generate revenue through carbon capture