ODP.NETでLONG RAW型の項目からデータを読み出すには

StringBuilder sbw00Select = new StringBuilder("");
sbw00Select.Append("SELECT BIN_EXCELDATA , ");  //ExcelBinaryデータ
sbw00Select.Append("       DATA , ");
sbw00Select.Append("  FROM WORK ");
sbw00Select.Append(" WHERE A = '" + strA + "' ");
sbw00Select.Append("   AND B = '" + strB + "' ");

//SQL実行
OracleDataReader odr = this.objOracle.oraSelect(sbw00Select.ToString());


//SELECT用メソッド
public OracleDataReader oraSelect(string sql)
{
    // SQL実行
    this.oc.CommandText = sql;
    this.oc.CommandType = CommandType.Text;
    try
    {
        this.odr = this.oc.ExecuteReader();
    }
    catch( Exception ex )
    {
        throw ex;
    }
    // 結果返却
    return this.odr;
}

string strExcelFile = "C:/work/upload.xls";
FileStream Fs;
BinaryWriter Bw;
Fs = new FileStream(strExcelFile, FileMode.Create, FileAccess.Write);
Bw = new BinaryWriter(Fs);

//Excelファイル作成
byte[] bytUpLoadData = new byte[100];
bytUpLoadData = (byte[])odr["BIN_EXCELDATA "];
Bw.Write(bytUpLoadData,0,bytUpLoadData.Length);