<?php

$txt = 'Текст   Текст       
	 
					 
	Текст             те    кст';
$patterns = [
	'/\n(\s*\n){2,}/',
	'/ {2,}/',
	'/\t/',
	
];
$replace = [
	PHP_EOL . PHP_EOL,
	' ',
	''
];
echo $txt = preg_replace($patterns, $replace, $txt), PHP_EOL;
echo '==================', PHP_EOL, nl2br($txt);