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CH4 w/ H2 Blend
2

CH4 w/ H2 Blend

CH4 w/ H2 Blend

(OP)
New Zealand's Firstgas Group says they will start delivery of CH4/H2 blend by pipeline in 2030 for use in electric generation via lower carbon emission gas turbines to be used in conjunction with renewable sources.
https://www.pipeline-journal.net/news/firstgas-gro...

RE: CH4 w/ H2 Blend

Dinosaur flatulence?

Please remember: we're not all rednecks!
www.sparweb.ca

RE: CH4 w/ H2 Blend

(OP)
While the source of the hydrogen is not explicitly stated, as you may remember the use of hydrogen as a future fuel source is typically proposed in conjunction with renewable energy sources being used to produce the H2. Since both are included in the description of the project, it is logical to assume that is Firstgas' intent here.

RE: CH4 w/ H2 Blend

(OP)
Catallaxy also says the Tx grid problem was caused by wind turbines, rather than unavailability of the gas turbine generators. The $6/kg cost is also questionable. Where did that come from? U.S. Department of Energy cost targets are $3.10/kg for central hydrogen plants and $3.70/kg for distributed hydrogen plants.

On the other hand, GE says their gas turbines will run on H2 blend. Not much of a stretch there.

RE: CH4 w/ H2 Blend

Texas grid articles by different authors...

Don't know where the $6 comes from, author cites "a number of places". Australian dollars I assume, though not explicitly stated.

To me the figure of interest is the net power output. Again, assuming the authors numbers, 188 MW in, 34 out. Hydrogen "economy".

The problem with sloppy work is that the supply FAR EXCEEDS the demand

RE: CH4 w/ H2 Blend

In parts of the UK they are generating H2 via electolizers using wind turbines. The electrolizers don't care about fluctuating power levels. They are blending 10% into NatGas distribution lines.
I am working on an industrial project where they will have both wind and solar power all feeding the electrolizers. Basically using H2 as a storage system. H2 is used in the process so we may end up not even burning any of it.
Lots of investment, very little operating cost.
Hitachi has been running land based turbines on 100% H2 for a couple of decades.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

RE: CH4 w/ H2 Blend

Does anyone want to talk about how Hydrogen slowly and eventually attacks all carbon steel ?.... No ????? .... Wrong Forum ???

Is a "little bit" of pipeline Hydrogen cracking risk acceptable to the public ? .... Lets talk with the Nuclear Power people about getting the public to accept a "little bit" of risk for vast long term benefit

https://www.twi-global.com/technical-knowledge/faq...

Nothing is easy ....

It's fun to talk about substituting H2 for Methane and using existing carbon steel pipelines and infrastructure .... makes things feasible and cheap !!!

.......and, of course you will not lose any of the precious hydrogen through pipe flange gaskets or valve stems that were originally selected to transport the big and heavy molecules of Natural Gas ..... Right ???? ..... Right ????

..... and when you store Hydrogen, you have to compress it and the gas temperature increases !!! thereby, you have increased the Hydrogen threat for cracking somewhere in the system.

We currently do not store NAT gas/methane in pressure vessels .... storage is done at the gas well. Will we not have to design, specify and construct fairly massive Hydrogen Compression and Storage facilities across the country ? ..... no Comments ?????

Who will want to live near these potential "Bombs" ??

What about the increased cost for inspection of existing Nat Gas piping systems that have been repurposed for mixed gas ?...... Don't they require additional periodic inspection to determine the amount of dangerous cracking induced by Hydrogen ?

Oh, wait !!!.... I forgot ..... we will soon have massive numbers of newly-minted STEM ENGINEERS available to solve these problems ....

(former hamburger flippers, sure .... but young and enthusiastic none the less)

Anybody have anything here on what is practical (and what is not) ??

?????????

MJCronin
Sr. Process Engineer

RE: CH4 w/ H2 Blend

(OP)
Distribution pipelines leak quite a bit of methane. More than they should, but nobody is doing much about it until they take out a city block or two. The pipeline insurance companies pay up and keep on letting them get away with it. I have written my senators and others urging better design, operation and maintenance requirements be introduced into law. Please do the same. You can include adequate credentials, experience and professional engineer only designer qualifications as a requirement exactly as I have recommended to keep the MBA well and away from the work.

The biggest problem with H2 in the current systems is keeping it out of the welds during pipe fabrication and assembly. As your link states, H2 is not usually adsorbed by steel, unless high temperatures make it possible, ie during welding. Other than that, pipelines operate at low temperatures. H2 induced stress corrosion cracking is problematic for high pressure pipelines, but the risk is supposedly small for well designed, maintained and routinely inspected pipeline systems. The problem has been adequately controlled for the most part with improvements in pipe fabrication techniques since the 80's. As for the rest, ASME B31.12, Hydrogen Pipeline Design, which I have not had occasion to read yet, surely will adequately address that well known issue to keep risk within acceptable levels, at least for the pipeline industry. Blending H2 with methane should reduce the risk further. The use of flanges in Cross Country pipelines is undesirable for many reasons, so much of that risk will be confined to stations and company properties, although there will be some additional leakage at valve stems at intermediate shut down valves. I imagine that ASME would not be wasting their time with developing B31.12, if any of them thought the result would not be acceptable for intended purpose. At this time, I am not aware of any company that is proposing that H2 actually be piped through the city for domestic use, but there are some studies and trials going on that probably will consider that service. Firstgas does envision this by 2050.

https://www.pipeline-journal.net/articles/ductile-...

https://www.pipeline-journal.net/articles/qualific...

Pipeline engineering specialist contractor Penspen, is working on H2 quality and integrity monitoring now.
https://www.pipeline-journal.net/articles/applicat...

If you get your hands on a B31.12, please let us know if that adequately addresses your concerns.

RE: CH4 w/ H2 Blend

(OP)
That $6/kg is inceed strange. If they are making H2 with renewable power, as the Catallexy article confirms, why would they need to buy H2 at market price? The cost of H2 is already included in the cap/op/ex of the project and there is no need to buy the H2 at additional cost.

It would also appear that the author is not aware of the low temperature H2 gen process that can be run at a far lower energy cost.

RE: CH4 w/ H2 Blend

$6/kg seems wildly optimistic according to https://arena.gov.au/assets/2016/05/Assessment-of-... Note these prices are in Australian dollars,

Our evaluation of the current and future (2030) cost of hydrogen from PV and electrolysis shows
that the potential cost using currently available technology is approximately $18.70/kg H2. The
base case system consists of a PV module with power electronics connected to a proton exchange
membrane electrolysis plant, which produces hydrogen only when the PV system is producing
power. The assessment is based on an estimated system cost of $2300/kW for a large scale, nontracking PV system with a mid-range capacity factor of 20.5% and a weighted average cost of
capital of 6.4%, as recently published by the CO2CRC (2015). It is assumed that the uninstalled cost
of the electrolyser and associated components is $2,285/kW, in line with recent estimates from
the European Fuel Cell and Hydrogen Joint Undertaking (Bertuccioli et al., 2014). Significant cost
reductions are predicted for both these technologies, cutting the estimated cost of hydrogen to
$9.10/kg by 2030.
The study also examined the potential of battery storage to reduce the cost of hydrogen
production. In this scenario, the battery system was used to condition the power supply from the
PV system, with sufficient storage capacity provided to enable continuous operation of the
electrolyser. Lithium-ion battery technology was selected as the most appropriate. In both current
and future scenarios, battery storage increased the cost of hydrogen relative to the base case, due
to its relatively high cost compared with energy production from PV. Based on current and future
battery costs of $540 and $200/kWh, the estimated cost of hydrogen was $28.40 and $11.30/kg in
2015 and 2030 respectively.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376: Eng-Tips.com Forum Policies http://eng-tips.com/market.cfm?

RE: CH4 w/ H2 Blend

For ambient temp/intermediate pressure service most pipeline steels are very content with hydrogen being used.
Some very old steels may have more issues.
High pressure and/or temp is much more problematic.
Likely the only utility with more leaks than gas distribution is water. It is a travesty that NatGas systems are so generally poorly maintained.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

RE: CH4 w/ H2 Blend

Quote (GregLocock)

So Firstgas didn't mention a hydrogen source? Point made.

Please tell me they're not getting the hydrogen from steam reforming ... with methane input.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

RE: CH4 w/ H2 Blend

Quote (MJCronin)

Oh, wait !!!.... I forgot ..... we will soon have massive numbers of newly-minted STEM ENGINEERS available to solve these problems ....

Relax, there's an app now for practically anything. Toilet paper, clean drinking water, world peace...

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

RE: CH4 w/ H2 Blend

(OP)
hydrogen from steam reforming is not the plan.

RE: CH4 w/ H2 Blend

I hear that "STEM" is being considered elitist and there's a move to change it to "STEAM" (or just "edukayshun").

Maybe that could provide a feedstock of H2 (and solve another problem at the same time) ?

another day in paradise, or is paradise one day closer ?

RE: CH4 w/ H2 Blend

You need a STEM brain, or a brain STEM, I can't remember which.
(Entropy and time have had their way with my brain.)

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

RE: CH4 w/ H2 Blend

Anyone who thinks we'll blend gases just to pump them, and then separate them again at destination, needs to give their head a very vigorous shaking.

Fraunhofer has really gone nuts this past while. First that useless overhyped "powerpaste" stuff- MgH2 used to make H2, with perhaps a cycle efficiency from electricity to electricity again in the single digits- and now THIS...

Yeah, you CAN separate H2 from methane using membranes. It's expensive and lossy to fight entropy needlessly this way though. And you end up losing a lot of your H2 in the methane (from which it was MADE, so obviously it's worth MORE than the methane) and you also get methane in your hydrogen- not something that makes fuelcells happy because they have to vent anode tailgas to get rid of it.

RE: CH4 w/ H2 Blend

(OP)
I did not read that they propose to use this for making fuel cells. Their stated intent is use "in the transportation and distribution of hydrogen as an energy source". Nothing about making fuel cells.

RE: CH4 w/ H2 Blend

ok, so if they burn H2, I hope they collect the water vapour ... a much more significant GHG than CO2.

and if they're messing with CH4, I hope none of this is escaping ... also a much more significant GHG than CO2.

another day in paradise, or is paradise one day closer ?

RE: CH4 w/ H2 Blend

(OP)
Pipelines and the oilfield in general began reducing methane emissions a long time ago. Progress has not been as fast as desired by many, which was also hindered by the previous government's "relaxation" of prior regulations.

Have you tried reducing your own water vapor, CH4 and CO2 emissions? neutral

RE: CH4 w/ H2 Blend

Water vapour IS a powerful GHG, but it is in rapid PHYSICAL equilibrium with water liquid in the oceans and biosphere. Water vapour emissions are NOT of concern from a global warming perspective. However, as we warm the planet, we shift the equilibrium from water liquid to water vapour in the atmosphere, which is a powerful feedback...

Yes, methane leakage is a big problem.

But here's the problem folks: people are talking about adding 20% H2 to methane and keeping it there for burning- which you can do. The gas distribution and fuel burning infrastructure can tolerate 10% easily but maxes out around 20% by volume.

Sadly, a 20% mixture of H2 in methane has 14% less energy content than pure methane...

The reduction in GHG emissions, assuming the hydrogen is electrolytic and made from electricity as pure as the driven snow, is therefore what- 6%? At most?

Great business if your customers are idiots- and pay per unit volume. Rather like adding water to gasoline...

RE: CH4 w/ H2 Blend

(OP)
94% is better than 0. Profit is not the motive. Its more of a continued existence sort of thing. It may get to the point where methane disappears from the pipeline entirely some day and they still want to have something inside to move around.

RE: CH4 w/ H2 Blend

Merchant gas has a min heat capacity, as they add Hydrogen they will just add less air.
Like they had to when they took the butane and ethane out of gas.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

RE: CH4 w/ H2 Blend

(OP)
I've never seen air being added. The problem is in fact usually the opposite in that gas from the well heads contain more Btu's than the average pipeline blend and the excess heavier HCs contributing to the higher Btu contents being removed. That also saves them from condensing in the pipeline as temperatures cool. What is left is pretty much methane with very small quantities <5% of ethane, butane plus a few other limited impurities normally yielding around 1050 Btu/cf. Pure CH4 has only 980 Btu/lbm, so you can see that nobody is purposely adding air to lower the Btu content, all that is needed is to remove the richer heavier compounds, which are sold separately. Neither is anyone adding air to a heavier blend just so they can transport that air cross country only to sell the gas at a lesser volumetric price, since gas you know is bought and sold by Btu content.

BTW Adding H2 to methane reduces the volumetric energy content. A 30% H2 blend into methane results in a CF having 863 Btu, 80% that of pipeline quality methane. Adding air will drop it a bit more, so no point in that.

Table 3-1. Typical Pipeline Gas Specifications

Characteristic Specification
Water content 4–7 lbm H2O/MMscf of gas
Hydrogen sulfide content 0.25–1.0 grain/100 scf
Gross heating value 950–1200 Btu/scf
Hydrocarbon dewpoint 14–40 °F at specified pressure
Mercaptans content 0.25–1.0 grain/100 scf
Total sulfur content 0.5–20 grain/100 scf
Carbon dioxide content 2–4 mol%
Oxygen content 0.01 mol% (max)
Nitrogen content 4–5 mol%
Total inerts content (N2 + CO2) 4–5 mol%
Sand, dust, gums, and free liquid None
Typical delivery temperature Ambient
Typical delivery pressure 400–1200 psig

RE: CH4 w/ H2 Blend

Quote (1503-44)

The problem is in fact usually the opposite in that gas from the well heads contain more Btu's than the average pipeline blend and the excess heavier HCs contributing to the higher Btu contents being removed.

Not to mention those heavier HCs are more valuable when separated.

"Everyone is entitled to their own opinions, but they are not entitled to their own facts."

RE: CH4 w/ H2 Blend

(OP)
"richer heavier compounds" Yes, "richer" has a double meaning when it comes to petroleum products.

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