create or replace trigger trg_temp_load 
before insert on temp
for each row
begin
:new."Description" := translate(:new."Description",'A"','A');
end;
/

SQL> with t as (
  2       select 'that''s a single quote and a "double" quote' x from dual)
  3  select translate(x, ' '||chr(39)||chr(34), ' ' ) from t;

TRANSLATE(X,''||CHR(39)||CHR(34),'')
---------------------------------------
thats a single quote and a double quote

SQL> select '''' from dual;

'
-
'

SQL> 

SQL> select 'abc''def' from dual;

'ABC''D
-------
abc'def

SQL> 

  1* select replace('abc''def','''',null) from dual
SQL> /

REPLAC
------
abcdef

SQL> 

SQL> with t as (
  2     select 'that''s a single quote and a "double" quote' x from dual)
  3  select replace(x, '''"') from t;

REPLACE(X,'''"')
------------------------------------------
that's a single quote and a "double" quote

SQL> with t as (
  2        select 'that''s a "single quote and a "double" quote' x from dual)
  3     select Translate(x, 'a''"','a') y from t;

Y
---------------------------------------
thats a single quote and a double quote

SQL> with t as (
  2        select 'that''s a "single quote and a "double" quote' x from dual)
  3     select REPLACE(REPLACE(x, ''''),'"') y from t;

Y
---------------------------------------
thats a single quote and a double quote

SQL>