diff --git a/warc_wat_url_processor.py b/warc_wat_url_processor.py
index 77a0cce..7b7f177 100644
--- a/warc_wat_url_processor.py
+++ b/warc_wat_url_processor.py
@@ -1,9 +1,9 @@
-import subprocess
 import os
 import gzip
 import re
 import traceback
-from multiprocessing import Pool
+from concurrent.futures import ProcessPoolExecutor, as_completed, wait
+import subprocess
 
 def extract_urls_from_file(file_path):
     urls = []
@@ -23,69 +23,77 @@ def extract_urls_from_file(file_path):
     return urls
 
 def process_file(file_path):
-    print(f"Processing file: {file_path}")
+    try:
+        print(f"Processing file: {file_path}")
 
-    # Extract URLs from the gzipped file
-    urls = extract_urls_from_file(file_path)
+        # Extract URLs from the gzipped file
+        urls = extract_urls_from_file(file_path)
 
-    # Create the output file path with '_urls.txt' extension
-    output_file_path = os.path.splitext(file_path)[0] + '_urls.txt'
-    print(f"Output file path: {output_file_path}")
+        # Create the output file path with '_urls.txt' extension
+        output_file_path = os.path.splitext(file_path)[0] + '_urls.txt'
+        print(f"Output file path: {output_file_path}")
 
-    # Write the URLs to the output file
-    with open(output_file_path, 'w') as output_file:
-        output_file.write('\n'.join(urls))
-    print(f"URLs written to {output_file_path}")
+        # Write the URLs to the output file
+        with open(output_file_path, 'w') as output_file:
+            output_file.write('\n'.join(urls))
+        print(f"URLs written to {output_file_path}")
 
-    # Use zstd command-line tool for compression
-    compressed_file_path = f'{output_file_path}.zst'
-    command_compress = f'zstd -T0 -12 --long {output_file_path} -o {compressed_file_path}'
-    subprocess.run(command_compress, shell=True)
-    print(f"Compressed file saved as '{compressed_file_path}'")
+        # Use zstd command-line tool for compression
+        compressed_file_path = f'{output_file_path}.zst'
+        command_compress = f'zstd -T0 -12 --long {output_file_path} -o {compressed_file_path}'
 
-    # Remove the original gzipped file
-    os.remove(file_path)
-    print(f"Original file removed: {file_path}")
+        # Run the compression command synchronously and wait for it to complete
+        compression_process = subprocess.Popen(command_compress, shell=True)
+        compression_process.communicate()
 
-    # Remove the original _urls.txt file
-    os.remove(output_file_path)
-    print(f"Original file removed: {output_file_path}")
+        print(f"Compressed file saved as '{compressed_file_path}'")
 
-    # Remove the line containing the filename (without "_urls.txt") from urls_to_download.txt
-    filename = os.path.basename(output_file_path).replace('_urls.txt', '')
-    command = f'sed -i "/{filename}/d" "urls_to_download.txt"'
-    if subprocess.run(command, shell=True).returncode == 0:
-        print(f"File {filename} has been successfully removed from urls_to_download.txt")
-        with open('urls_to_download.txt', 'r') as file:
-            remaining_count = sum(1 for line in file)
-        print(f"URLs remaining to be processed: {remaining_count}")
-    else:
-        print(f"Failed to remove {filename} from urls_to_download.txt")
+        # Remove the original gzipped file
+        os.remove(file_path)
+        print(f"Original file removed: {file_path}")
 
-def extract_urls_from_directory(directory_path):
-    file_list = sorted(os.listdir(directory_path))
-    pool = Pool(processes=7)
-    pool.map(process_file, [os.path.join(directory_path, filename) for filename in file_list if filename.endswith('.warc.gz')])
-    pool.close()
-    pool.join()
+        # Remove the original _urls.txt file
+        os.remove(output_file_path)
+        print(f"Original file removed: {output_file_path}")
 
-with open('urls_to_download.txt', 'r') as file:
-    urls = file.readlines()
+        # Remove the line containing the filename (without "_urls.txt") from urls_to_download.txt
+        filename = os.path.basename(output_file_path).replace('_urls.txt', '')
+        command = f'sed -i "/{filename}/d" "urls_to_download.txt"'
+        if subprocess.run(command, shell=True).returncode == 0:
+            print(f"File {filename} has been successfully removed from urls_to_download.txt")
+            with open('urls_to_download.txt', 'r') as file:
+                remaining_count = sum(1 for line in file)
+            print(f"URLs remaining to be processed: {remaining_count}")
+        else:
+            print(f"Failed to remove {filename} from urls_to_download.txt")
 
-urls = [url.strip() for url in urls]
+    except Exception as e:
+        print(f"Error during processing {file_path}: {e}")
+        traceback.print_exc()
 
-batch_size = 48
-concurrency_level = 4
-batches = [urls[i:i+batch_size] for i in range(0, len(urls), batch_size)]
-
-for batch in batches:
-    pool = Pool(processes=concurrency_level)
-
-    for url in batch:
+def download_and_process_file(url):
+    try:
         command = f'axel -n 4 {url}'
-        pool.apply_async(subprocess.run, args=(command,), kwds={'shell': True})
+        subprocess.run(command, shell=True)
+        file_path = os.path.join(os.getcwd(), os.path.basename(url))
+        process_file(file_path)
+    except Exception as e:
+        print(f"Error during download and processing {url}: {e}")
 
-    pool.close()
-    pool.join()
+def main():
+    with open('urls_to_download.txt', 'r') as file:
+        urls = file.readlines()
 
-extract_urls_from_directory(os.getcwd())
+    urls = [url.strip() for url in urls]
+
+    download_concurrency_level = 4
+
+    # Start downloading and processing files in parallel
+    with ProcessPoolExecutor(max_workers=download_concurrency_level) as executor:
+        futures = [executor.submit(download_and_process_file, url) for url in urls]
+
+        # Wait for all downloads and processing to complete before starting the next iteration
+        wait(futures)
+
+if __name__ == "__main__":
+    main()
\ No newline at end of file