Potassium Hydroxide (KOH)

Potassium hydroxide (KOH), commonly known as caustic potash, is the largest-volume potassium chemical for non-fertilizer use. It is produced by the electrolysis of potassium chloride with membrane cell technology.  Co-products are chlorine and hydrogen.A strong alkali, Potassium Hydroxide is available in both liquid and dry forms. It has applications in fertilizers, batteries, soaps and detergents, specialty glasses and other industrial operations. It also serves as a chemical intermediate for dyes, pharmaceuticals and photographic chemicals.

The industrial preparation of KOH is similar to that of NaOH, by the chlor-alkali process. It is prepared by the electrolysis of potassium chloride solutions, along with chlorine gas as a by-product:

2 KCl + 2 H2O → 2 KOH + Cl2 + H2

Potassium Hydroxide plant supplied by KALF is manufactured using electrolysis utilising membrane cell technology. Potassium salt in the form of brine is electrolysed to produce Potassium Hydroxide, Chlorine and Hydrogen. The solution is typically 32% in Strength which is concentrated to 50% & 90%-93% using evaporation.

KALF based on our own technology to design, supply, erection of Potassium Hydroxide plant as long as with KOH evaporator for produce of 90%-93% KOH flakes.

Multiple-effect Evaporation System

KALF designed Multi-effect falling film evaporators mainly adapts in continuous evaporation and concentration under low temperature for NaOH and KOH Especially suitable for processing the material with character of heat sensitive, viscosity and foamability. The machine has characteristics of high heat transfer efficiency, material heating In short time etc.


Each stage consisting of Evaporators & separators, condenser, heat pressure pump, sterilizer, insulating tube, material transfer pumps, condensate water pump, operation platform, electric meter control cabinet, valve, pipeline etc.


  • High heat transfer efficiency and material heating In short time realized for the heating system even heated with steam and feed liquid
  • evaporated in flow film style, The equipment has lower energy & Steam consumption and lower cooling water circulation capacity if equipped with heat pressure pump.
  • Feed liquid evaporated while accelerated flow downward along the pipe wall that suitable for evaporation and concentration of high viscosity material.
  • Liquid heated in a very short time for it inner film evaporated at every tubes which is highly suitable for chlor-alkali application.
  • Whole process operated under vacuum condition Which meet the sanitary requirement and environmental protection requirement, Meanwhile it can be reduce the temperature of evaporation significantly, If it equipped with heat pressure pump, and the secondary steam will be re-inhaled and mixed with new steam. Steam pass through pump, spray into heating shell, spread rapidly and make liquid heated gently, its suitable for concentration of heat sensitive products.
  • Equipment suitable for evaporation and concentration of foamability material, Liquid film evaporated in heating tube then formed liquid-vapor separate, meanwhile the most liquid of feed extracted from the bottom of cylinder, Only small amount of feed liquid and all secondary steam enter into separator, therefore Feed liquid foam formed can be completely avoided in the whole process.
  • Equipment can also sterilize food Feed liquid flow to sterilizer after preheated,Temperature up to 94ºCand lasting for 24 seconds,Then flow into first stage,Liquid evaporated in seconds then temperature drop at once.
  • Continuously working and produced flakes.
  • System automatic control feed material capacity, heat temperature and discharge viscosity and cleaning. Can equip with protection facilities in case of suddenly blackout, break down which will cause trouble with heat sensitive products, other safeties issue, alarm facilities can achieve automatic operate and control.