多队列。如何指定用哪一个队列

'consumer'  => [
    'handler'     => Webman\RedisQueue\Process\Consumer::class,
    'count'       => 18, // 可以设置多进程同时消费
    'constructor' => [
        // 消费者类目录
        'consumer_dir' => app_path() . '/queue/redis'
    ]
],
'consumer_slow'  => [
    'handler'     => Webman\RedisQueue\Process\Consumer::class,
    'count'       => 1,
    'constructor' => [
        // 消费者类目录
        'consumer_dir' => app_path() . '/queue/redis/slow'
    ]
],