#!/usr/bin/env perl

use strict;
use warnings;

use Inline::Files;

my %seq; # example: 'scooped up again' => 'scoopedbbbupbbbagain',

while (my $line = <SEQ>) 
{
    $line =~ s/^\s+//;
    $line =~ s/\s+$//;

    ($seq{$line} = $line) =~ s/\h+/bbb/g;
}   

my $search_phrases = join '|', keys %seq;
my $re = qr{($search_phrases)};

while (<TXT>) {
    s/$re/$seq{$1}/g;
    print;
}   

__SEQ__
          scooped up by
          social travesty
          without proper sanitation
__TXT__
Many of them are scooped up by chambermaids, thrown into bin bags and sent off to landfill sites, which is a disaster for the environment and a social travesty given that many people around the world are going without proper sanitation.