for (int i = 0; i < DocumentRow.RowCount; i++)
            {
                ++DocumentRow.Row;
                Range.SetValue(ExcelRow, 1, DocumentRow.Значение1);
         --//--
                Range.SetValue(ExcelRow, 7, DocumentRow.Значение7);
                ExcelRow++;
                if (ExcelRow >= 16000) { Excel.WriteRange(Range); }; //<< Начиная с 16000 строки добавлять в книгу при каждой итерации по 16000+ строк...
            }

using System;
using System.Text;
using System.Windows;
using Excel = Microsoft.Office.Interop.Excel;

namespace ConsoleApplication1
{
    class Program
    {
        [STAThread]
        static void Main(string[] args)
        {
            Excel.Application oXL;
            Excel._Workbook oWB;
	        Excel._Worksheet oSheet;
            oXL = new Excel.Application();
            oWB = (Excel._Workbook)(oXL.Workbooks.Add());
            oSheet = (Excel._Worksheet)oWB.ActiveSheet;
            StringBuilder sb = new StringBuilder();
            for (int i = 1; i <= 36000; i++)
            {
                sb.AppendFormat("{0}\t\t\t\t\t{1}\r\n", i, "Тра-ла-ла");
            }

            System.Windows.Forms.Clipboard.SetText(sb.ToString());
           
            oSheet.Cells[1, 1].PasteSpecial();
            oXL.Visible = true;
            oSheet = null;
            oWB = null;
            oXL = null;
        }
    }
}