diff --git a/trimage/ThreadPool/ThreadPool.py b/trimage/ThreadPool/ThreadPool.py
index 9f9e051..17e55e4 100644
--- a/trimage/ThreadPool/ThreadPool.py
+++ b/trimage/ThreadPool/ThreadPool.py
@@ -30,9 +30,6 @@ class ThreadPoolMixIn:
     def __init__(self, threadpool=None):
         if (threadpool == None):
             threadpool = ThreadPool()
-            self.__private_threadpool = True
-        else:
-            self.__private_threadpool = False
 
         self.__threadpool = threadpool
 
@@ -52,10 +49,6 @@ class ThreadPoolMixIn:
     def process_request(self, request, client_address):
         self.__threadpool.add_job(self.process_request_thread, [request, client_address])
 
-    def shutdown(self):
-        if (self.__private_threadpool): self.__threadpool.shutdown()
-
-
 class AddJobException(Exception):
     '''
     Exceptoion raised when a Job could not be added
diff --git a/trimage/trimage.py b/trimage/trimage.py
index 3f7dbc3..1ef81be 100644
--- a/trimage/trimage.py
+++ b/trimage/trimage.py
@@ -409,9 +409,6 @@ class Worker(QThread):
         self.toDisplay = Queue()
         self.threadpool = ThreadPool(max_workers=cpu_count())
 
-    def __del__(self):
-        self.threadpool.shutdown()
-
     def compress_file(self, images, showapp, verbose, imagelist):
         """Start the worker thread."""
         for image in images: