For using on Area rug fringes, the citrus solv would act as a good detergent for the main dirt, but Citrus Solv is prone to leaving residue and is highly alkaline, hence I dont think its the best thing to use on fringes, unless the fringes have some sort of oil or grease on them. Citris Solv is a degreaser, works great at breaking down oily soils and grease.

Use your regular prespray, rub it in with a brush then extract with the wand. You can put another piece of carpet underneath if extracting with the wand, or if they are hanging up you can use your upholstery tool and wear a rubber glove to make sure they are well rinsed and extracted.

After "detergent" cleaning, spray the fringes with acetic or citric acid and comb it through with an old hair brush and leave to dry. This will help to ensure they dry bright without yellowing. Dont hang red orientals to dry that have white fringes, dry them flat.