I suggest that you explore using boiling water:

See for example:

https://homeguides.sfgate.com/use-hot-water-weed-control-95265.html

https://drecampbell.com/killing-weeds-with-boiling-water/

and there are You Tubes on the subject as well.

No registration required and no residues...

All the best.

Another option that could be useful is plasticulture (plastic mulch), to prevent weed growth.

Mulching with plastic sheet, use of biaagents, regular physical removal and spray with sodium chloride are some important options.

Thank you to those who provided an answer. Note, I am asking about options in broadacre farming situations. I am referring to grain and fibre crops. These areas can be hundreds of hectares on a farm.

I appreciate boiling water would work but not be energy efficient in a global warming world and I am not aware of machines that could cover a 100-hectare paddock in a few hours.

Plastic mulch is used with medicinal hemp and in horticulture crops. These are high-value crops and can afford the $1,000 odd dollars to lay down the plastic. The grain and fibre crops do not have enough dollar return to make this affordable. This is not likely a good use of resources and again a global warming issue. Negates hemp's potential carbon positive footprint. Medicinal hemp uses spaced plants totalling 10,000-20,000/ha. Grain and fibre crops need 500,000- 600,000 plants/ha. These are not row crops. You cannot chip, interrow spray or boil between these plants when you have 50-100 per square metre.

This is why we need a herbicide option. This is not a request for "potted pot know-how". The silence confirms what I suspected that there are no herbicide options researched anywhere in the world.