For capacity reasons, {HEAD ~ several ultrafiltration modules} may be required in {TAIL ~ an industrial environment} 
required in
For capacity reasons , { HEAD ~ several ultrafiltration modules } may be required in { TAIL ~ an industrial environment }
OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH REL REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL