Using nanofiltration to concentrate the end of ultrafiltration filtration and making certain of the concentrated multiple, the problem to extract the broth has turned out. To use the membrane technology including the ultrafiltration and nanofiltration membrane,the filtration of higy concentration can be got,and the yield of filtration has been increased. With the use of this method,the volume of the filtration decreases 25 percent,the yield can increase 1 percent,the volume of the COD of the broth waste can decrease 96 percent.