Luckily I backed up what I had already synchronized, so that I do not have to start from scratch.
When I finish synchronizing, I will provide a windows snapshot.
how to speed up the sync of Emerald wallet
download the Emerald Blockchain Snapshot https://snapshot.emeraldcrypto.de
put and unpack the snapshot.zip file into your Emerald directory
start the Emerald client (emerald-qt.exe for linux/windows and emeraldd for linux) with the option -reindex
now the indexing of the copied blockchain is started
https://www.emeraldcrypto.de/FAQ/FAQ.html
workaround for Emerald Crypto on Ubuntu 18.04 LTS
download the emerald daemon from github (emeraldd) https://github.com/Crypto-Currency/Emerald/releases/tag/V0.8.7.7
download the libboost libraries 1.58 and unpack the on /usr/lib/x86_64-linux-gnu/
start the emerald client