If it's not ideal right now, how well does it scale if more and more desalination plants come online to meet freshwater demands, and dispose of their brine in the same manner?
The global water cycle is the embodiment of scale and even though engineers would learn a lot of interesting new things and make mistakes in the process of implementing desalination at scale, the brine problem is trivially solvable with existing technology like longer pipes and flow control (changing the exhaust concentration based on ocean currents and seasonal factors).
The problem is the criminal mispricing of water in most of the world. Anything that interacts with saltwater - especially brine - is in a completely different class of infrastructure that requires constant maintenance, something that most political systems are especially bad at. It's compounded by the artificially low price of water and accompanying lack of funds.
Humans have built over three million kilometers of natural gas and oil pipelines globally. The longest undersea pipeline is over 1,200 km long, which is at least twenty times longer than the longest pipelines we'd need to build for ideal brine dispersion in the worst case geographies. For better or worse, the problems with desalination are economic and political, not technological. We just need to spread out our impact so that it's within the margin of error of ocean currents and evaporation.
This statement could mean just about anything. My understanding is that desalination plants often have a fairly-sizable fairly-dead-zone around them, taht the salinity is a pretty pronounced local issue.
Sea-water is about 3.5% salt by weight. Are you saying that the brine water coming out is 3.5 * 1.025% salt, or that it's 5.5% salt? Do you have anything you can cite? What % of the water that goes in the inlet makes it to the "brine" outlet?
Yeah the local imbalance is what worries me. I have a mental image of a big long 'soaker hose' style brine dumping pipe rather than a single outlet, that way the brine is further diluted. Wonder how much that helps.
The problem is the criminal mispricing of water in most of the world. Anything that interacts with saltwater - especially brine - is in a completely different class of infrastructure that requires constant maintenance, something that most political systems are especially bad at. It's compounded by the artificially low price of water and accompanying lack of funds.
Humans have built over three million kilometers of natural gas and oil pipelines globally. The longest undersea pipeline is over 1,200 km long, which is at least twenty times longer than the longest pipelines we'd need to build for ideal brine dispersion in the worst case geographies. For better or worse, the problems with desalination are economic and political, not technological. We just need to spread out our impact so that it's within the margin of error of ocean currents and evaporation.