diff --git a/conf/modules.config b/conf/modules.config
index f83fd98..f9bd285 100644
--- a/conf/modules.config
+++ b/conf/modules.config
@@ -106,7 +106,7 @@ process {
                 "-s ${parse_int(params.wfmash_segment_length)}",
                 "-p ${params.wfmash_map_pct_id}",
                 params.wfmash_merge_segments   ? "-M"                                : "",
-                params.wfmash_exclude_delim    ? "-Y ${params.wfmash_exclude_delim}" : "-X",
+                params.wfmash_exclude_delim    ? "-Y \"${params.wfmash_exclude_delim}\"" : "-X",
                 params.wfmash_no_splits        ? "-N"                                : "",
                 params.wfmash_block_length     ? "-l ${parse_int(params.wfmash_block_length)}"  : "-l ${parse_int(params.wfmash_segment_length) * 5}",
                 "-k ${params.wfmash_mash_kmer}",
@@ -129,7 +129,7 @@ process {
                 "-s ${parse_int(params.wfmash_segment_length)}",
                 "-p ${params.wfmash_map_pct_id}",
                 params.wfmash_merge_segments   ? "-M"                                : "",
-                params.wfmash_exclude_delim    ? "-Y ${params.wfmash_exclude_delim}" : "-X",
+                params.wfmash_exclude_delim    ? "-Y \"${params.wfmash_exclude_delim}\"" : "-X",
                 params.wfmash_no_splits        ? "-N"                                : "",
                 params.wfmash_block_length     ? "-l ${parse_int(params.wfmash_block_length)}"  : "-l ${parse_int(params.wfmash_segment_length) * 5}",
                 "-k ${params.wfmash_mash_kmer}",
@@ -153,7 +153,7 @@ process {
                 "-s ${parse_int(params.wfmash_segment_length)}",
                 "-p ${params.wfmash_map_pct_id}",
                 params.wfmash_merge_segments   ? "-M"                                : "",
-                params.wfmash_exclude_delim    ? "-Y ${params.wfmash_exclude_delim}" : "-X",
+                params.wfmash_exclude_delim    ? "-Y \"${params.wfmash_exclude_delim}\"" : "-X",
                 params.wfmash_no_splits        ? "-N"                                : "",
                 params.wfmash_block_length     ? "-l ${parse_int(params.wfmash_block_length)}"  : "-l ${parse_int(params.wfmash_segment_length) * 5}",
                 "-k ${params.wfmash_mash_kmer}",
@@ -186,7 +186,7 @@ process {
                 "-s ${parse_int(params.wfmash_segment_length)}",
                 "-p ${params.wfmash_map_pct_id}",
                 params.wfmash_merge_segments   ? "-M"                                : "",
-                params.wfmash_exclude_delim    ? "-Y ${params.wfmash_exclude_delim}" : "-X",
+                params.wfmash_exclude_delim    ? "-Y \"${params.wfmash_exclude_delim}\"" : "-X",
                 params.wfmash_no_splits        ? "-N"                                : "",
                 params.wfmash_block_length     ? "-l ${parse_int(params.wfmash_block_length)}"  : "-l ${parse_int(params.wfmash_segment_length) * 5}",
                 "-k ${params.wfmash_mash_kmer}",