Detergent Spray Drying Tower

Are you ready to start your own production of synthetic detergent powder?

STPP Group offers a full package of solutions, from initial feasibility study to operational facility handover, followed by worry-free raw material supplies and lifetime aftersales support.

Synthetic detergent powder spray drying process

Most of the synthetic washing detergents consumed today are lightweight puffed powders with a bulk density range of 250-500 g/l, and good free-flowing property. The formulas principally consist of hollow particles with dimensions of 0.2-2.5mm.

The most reliable way to produce such lightweight puffed detergent powder is a spray drying process.

Compared to Dry Mixing and Agglomeration processes, Spray Drying delivers a superior outcome. Besides weight, the spray-dried detergent powder is almost perfectly dehydrated, which prevents agglomeration and caking of the final product. In addition, the spray drying process offers significantly improved efficiency and capacity.

As the key features of the powder detergent manufacturing process, spray drying towers are immense constructions. On average, they measure 3-12 meters in diameter and 20-35 meters in height. The output capacity projects from 1 ton/hour to 30 tons/hour.

Production process description


Raw Materials Storage and Transport

An average synthetic detergent formula features 9-17 ingredients. All raw materials are sorted into two types: the solid and the liquid. Solid ones are prevalent in powder forms, such as Sodium Sulfate Anhydrous, Soda Ash Light, STPP, and others. Solid raw materials are commonly packed in woven bags and stored in appropriate warehouse conditions, from where they get transported by conveyor belt or pneumatic lift for dosing. Liquid ones, such as Surfactants, Caustic Lye, Sodium Silicate Solution, and Fragrances, are contained in tanks and drums and transported by pipes.


Solid and Liquid Raw Materials Dosing

According to the target formula, each raw material is measured and dosed in a process automatically monitored and controlled by a PLC system.

Besides monitoring, the PLC system saves all formula information, allowing storage and full control over hundreds of different production formulas.


Slurry Preparation and Aging

All base raw materials (LABSA, Caustic lye, Sodium silicate solution, Soda ash light, Sodium sulfate anhydrous, STPP, etc.) are dosed and delivered to the cruncher in the dosing process. Here they get transformed into the base powder compound, normally known as the Detergent Slurry. The slurry is then transported for the aging of up to 30 minutes in the aging tank.


Spray Drying

Aged detergent slurry is pumped to the top of the spray drying tower and sprayed from nozzles in the tower to form atomized droplets. Meanwhile, hot air produced in the furnace dehydrates the droplets, so they fall down as hollow particles, free of moisture, to form a semi-finished base powder.

We are able to provide different furnaces for different conditions, based on the fuel accessibility in the specific area. Our products can cover gas, coal, heavy oil, and biomass fuel.


Exhaust Air Filtration and Scrap Recycling

After the hot air cools down, it’s mixed with fine dust residue. Dust removing devices are used to filter the exhaust air before being discharged. Collected particles must be recycled for dosing as raw materials.


Post-Tower Raw Material Dosing, Blending, and Final Packing

In this part of the process, raw materials like Fragrances, Enzymes, Nonionic surfactants, and Color Speckles are usually dosed into the base powder and blended in a post-tower blender, as these raw materials cannot pass through the spray drying process due to limits of their own properties. After integrating, the compound becomes the final finished powder with complete functions as formulated, ready for delivering to the storage bins and from there further to packing machines.

A selection of both manual and automatic packing machines is available. Options include packaging of the final finished powder into pouches, boxes, buckets, and woven bags.

An alliance between two giants

Over the last 10+ years, STPP Group has been partnering with another industry leader, Zhejiang Meibao Industrial Technology Co., Ltd. MEIBAO INDUSTRIAL has long been dedicated to designing, developing, and supplying industrial chemical plants in various sectors, including synthetic detergents, cements, fertilizers, and others.

To maximize the respective advantages of our two enterprises, we established a joint project team, JPT-MS. The team is made up of 16 experts from both enterprises, featuring more than 100 years of combined experience in detergent manufacturing. Experts from STPP Group possess plenty of know-how in the operation of detergent plants, while experts from MEIBAO INDUSTRIAL have abundant experience in designing, supplying, and installing synthetic detergent plants. Together we employ the most advanced technologies and the most durable materials.

STPP Group takes pride in its comprehensive life-time after-sales services. Our core business and the ultimate goal is the global supply of detergent raw materials. The motivation to supply the most dependable and durable plants comes from a desire to ensure stable and smooth production so that we can mutually thrive through the long-term parntership.

We provide quality based on a simple motto: One day off at your plant is also one day wasted for STPP Group!

We offer flexible options

Two main outputs of the detergent spray drying process are Base Powder and Final Product. The process can be conducted in two entirely independent phases. Depending on the clients’ plans, it’s possible to deliver and set-up only the post-tower processing line, in which case the base powder will be manufactured and supplied externally.

It’s also possible to invest in only the packing line and buy complete finished detergent powder in bulk packing (25kg, 50kg, 500Kg, etc.) for repacking into branded commercial washing powder.

Post-tower detergent base powder processing line

Post-tower detergent base powder processing line

STPP Group provides unbeatable package of services for the post-tower base powder processing plants. We design, supply, and install the plant, meticulously tailored to fit your specific needs. Furthermore, we supply base powder, auxiliary chemicals, and packaging materials.
We also provide lifetime after-sales services! STPP Group's first overseas subsidiary, DAFA SOAP AND DETERGENT MANUFACTURING PLC in Ethiopia, is an efficient exemplary model for the success of this type of cooperation. You are most welcome to visit and get familiar with the entire process on-site.

Ask an expert

Did we forget something? Do you have a specific issue that needs a solution? Consider it done! Our professionals are at your service 24/7, ready to answer every question in a clear and concise manner.

No. STPP Group does not supply Dry mixing and Agglomeration process detergent plants. We only supply synthetic detergent plant of Spray drying process.

As far as we have learnt, the other suppliers who supply detergent plants are only Machinery manufacturers or traders. Compared to them, the alliance of STPP Group and MEIBAO INDUSTRIAL is holding below obvious advantages.

  • STPP Group owns 3 detergent plants. We ourselves have been producing synthetic detergents since 1994. STPP Group’s engineering team, as the user and operator for more than 2 decades, knows about the detergent plant equipment very well. Compared to the engineers who only design and manufacture equipment, our team knows better what good equipment should be like – in practice.
  • We offer turn-key solutions and lifetime aftersales services. STPP Group’s core business and ultimate goal is to supply detergent raw materials. We help our customers to implement manufacturing plants, so that STPP Group can supply raw materials in the long run. So, it stands to reason that we are motivated to supply quality equipment and provide lifetime aftersales services, to ensure stable and smooth production on your side. 
  • STPP Group is competitive on prices. As our ultimate purpose is to supply you with raw materials on a regular basis. We don’t seek high margin on supply of plant equipment. However, the machinery manufacturers must lock their margin level as the supply of equipment is likely to be a one-time business for them.

Yes, we are able to supply all supplementary units, including Sulfonation line of LABSA, Caustic soda dissolving unit, Sodium silicate dissolving unit or production line(from Silica sand and Caustic soda), and so on.

Have more questions?

Contact our product manager now, to get fast and in-depth answers.

Angie Liu

Product Manager

  • Fill in below fields, and I will get back to you with in-depth answers in 24 hours.