code: public function removeColumn($pColumn, $pNumCols = 1)
      {
          if (!is_numeric($pColumn)) {
              $highestColumn = $this->getHighestDataColumn();
              $pColumn = Coordinate::stringFromColumnIndex(Coordinate::columnIndexFromString($pColumn) + $pNumCols);
              $objReferenceHelper = ReferenceHelper::getInstance();
              $objReferenceHelper->insertNewBefore($pColumn . '1', -$pNumCols, 0, $this);
              for ($c = 0; $c < $pNumCols; ++$c) {
                  $this->getCellCollection()->removeColumn($highestColumn);
                  $highestColumn = Coordinate::stringFromColumnIndex(Coordinate::columnIndexFromString($highestColumn) - 1);
              }
          } else {
              throw new Exception('Column references should not be numeric.');
          }
  
          return $this;
      }
docs: Remove a column, updating all possible related data.
  
  @param string $pColumn Remove starting with this one, eg: 'A'
  @param int $pNumCols Number of columns to remove
  
  @throws Exception
  
  @return Worksheet