If you are going to take the trouble, you can also wash silk blankets by hand.
Fill a container with lukewarm water and add 1/4 capful of mild liquid laundry detergent for every gallon of water. Submerge the silk blanket in the water and swirl it around with your hand. Allow it to stay in water for two to three minutes. Rinse it in a clean container filled with clean, lukewarm water. Add 2 to 3 tbsp of white vinegar to the clean rinse water to neutralize the soap residue, if desired. If you add vinegar, you need to rinse it once more in clean, lukewarm water. Lightly squeeze the blanket to rid it of excess water. Do not wring it.
Wow, washing Chinese silk blanket by hand is really a delicate job, can you ladies do it now?