A really big desalination facility

A single nuclear power plant demands 8 desalinators worth of fresh water. Even with recycling water, it still comes to a lot of space and piping.
It gets even worse for large projects like, say, focusing on nuclear desalination for everything. Then you might have dozens of desalinators.
A large desalination module 4-8 times the capacity of the small one would be a nice improvement.

Reverse osmosis filter, does not need steam and requires less energy but consumes osmosis filter elements.

希望增加更大的抽水和排水设施，更高级的管道，现在的抽水泵要满足一座三级核电站满功率运行淡化海水需要64台抽水器和16根三级管道，这要占据相当长的海岸线

Totally agree, a larger facility is needed. In some of my end-game maps I had entire coastlines of desalinators and dumps.

Or a modular facility which you can expand somewhat dynamically.