麦草NH4OH-KOH制浆清洁工艺

以氨水为主，添加少量苛性钾碱对麦草原料进行蒸煮，少量钾碱作为强碱不仅能减少氨量、缩短蒸煮时间，而且可为黑液中氨木素提供钾源.蒸煮黑液经回收游离氨后含有农作物生长所需的多种成分，可进行黑液资源化综合利用，使草浆生产实施清洁工艺.一种方法是将黑液直接作为液体肥料用于农田灌溉；另一种方法是将黑液在碱性条件下絮凝沉降，生成的絮凝沉降物经化学改性，可制备功能性肥料用于农业生产；上层清液呈碱性，补加NH₄OH-KOH后，作为工艺水循环重新用于蒸煮.从根本上消除草浆生产黑液的污染问题，建立起造纸工业和农业之间物质良性循环新模式.

CLEANER PROCESS OF NH4OH-KOH PULPING OF WHEAT STRAW

A cleaner process of wheat straw pulping with aqueous ammonia containing a small amount of caustic potash was studied.The caustic potash as a strong base not only could reduce the needed quantity of NH 3 used and cooking time, but also enriched black liquor with potassium element.The black liquor after recovering excess NH 3 contained nitrogen, potassium and organic substance and could be used as a fertilizer.The black liquor could be applied as liquid fertilizer directly,or the black liquor could be treated by coagulation in alkaline condition and the precipitate could be chemically modified to solid fertilizer.The clear liquid after precipitation could be recycled to cooking by adding NH 4OH and KOH.The environmental pollution of black liquor would be solved and a new pattern of virtuous cycle was set up between paper industry and farming.