Chemical Dosing PumpSupplier in Bangladesh
EMEC and SEKO solenoid and motor-driven diaphragm metering pumps from Italy for ETP, WTP, boiler and cooling tower chemical dosing, supplied with installation and after-sales support by Techno Bangla Creation.
What Is a Chemical Dosing Pump?
A chemical dosing pump, also called a metering pump, injects a small, controlled amount of chemical into water or process liquid. Each stroke moves a set volume, so flow can be set and repeated. ETP, WTP, boiler and cooling tower plants use it to dose coagulants, acids, alkalis, polymers and disinfectants.
A dosing pump is not a transfer pump. A transfer pump moves liquid in bulk, such as a drum and container pump, while a dosing pump delivers precise small flows. See the EMEC and SEKO pages for brand details.
- Solenoid pumps for small flows and electronic control
- Motor-driven diaphragm pumps for larger flows and higher pressure
- Wetted parts in PVC, PP, PVDF, PTFE, SS-304 and SS-316
- Installation and after-sales support in Bangladesh
Chemical Dosing Pump Specifications
- Solenoid Driven Pump
- 1 ~ 16 L/h (about 0.27 L/min), 1 ~ 20 bar (about 0.1 ~ 2 MPa)
- Motor Driven Diaphragm Pump
- 1 ~ 1000 L/h (about 1 m³/h), 1 ~ 100 bar (about 0.1 ~ 10 MPa)
- Wetted Part Material
- PVC, PP, PVDF, PTFE, SS-304, SS-316
- Liquids
- Normal chemicals, corrosive liquids, hot liquids and other substances
- Application
- Waste water, boiler water, cooling tower, high-viscosity liquids
- Industries
- Chemical, textile, pharmaceutical, food and beverage
- Brand
- EMEC, SEKO
- Origin
- Italy
Flow, pressure, material and control options depend on the model you select. Send us the chemical, dose rate and back pressure and our engineers will confirm the right pump.
Solenoid vs Motor-Driven Diaphragm Dosing Pump
Both are diaphragm metering pumps. The drive decides the flow, pressure and control you get.
| Feature | Solenoid Driven Pump | Motor Driven Diaphragm Pump |
|---|---|---|
| Drive | Electromagnetic coil pushes the diaphragm in pulses | Motor and cam or eccentric move the diaphragm |
| Our range | 1 ~ 16 L/h, 1 ~ 20 bar | 1 ~ 1000 L/h, 1 ~ 100 bar |
| Control | Electronic stroke and frequency setting, and it can follow a flow-meter pulse signal | Stroke length adjustment, often with a speed controller |
| Accuracy | Confirm on the datasheet of the exact model | Technical papers quote about ±2% for mechanical diaphragm pumps |
| Size and design | Compact, few moving parts | Larger, simple mechanical design |
| Maintenance | Valves and diaphragm need preventive care | Valves and diaphragm need preventive care |
| Cost | Often slightly higher with controls, as reported in water treatment guides | Often lower for the same duty |
| Best fit | Small dosing of polymer, disinfectant and inhibitors | Higher-flow ETP coagulant, acid and alkali dosing |
Typical values from engineering and manufacturer sources. Always confirm against the datasheet of the exact model.
How Does a Dosing Pump Work?
- Diaphragm Pulls BackThe drive moves the diaphragm back and creates suction in the pump head.
- Chemical Is Drawn InA suction check valve opens and lets chemical in from the tank.
- Diaphragm Pushes ForwardThe suction valve closes and the diaphragm pushes a set volume out.
- Chemical Is InjectedThe discharge valve opens and the dose enters the pipe or tank at the injection point.
- Dose Is AdjustedStroke length, stroke rate or a signal from a pH analyzer or flow meter sets the flow.
Which Pump Head Material for Which Chemical?
Wrong material is a common cause of leaks and pump head damage. Match it to the chemical, strength and temperature.
| Material | Commonly Used For | Note |
|---|---|---|
| PVC | Sulfuric acid, PAC, caustic soda, aluminium chloride | More sensitive to heat than PP or PVDF |
| PP | Caustic soda, hydrochloric acid, many general chemicals | Often rated roughly 4 to 60 °C |
| PVDF | Sodium hypochlorite, stronger acids, chlorine | Wider temperature range, also used in food-grade duty |
| PTFE | Diaphragms and parts for most acids and solvents | Very wide chemical resistance |
| SS-316 | Dilute sulfuric acid, phosphoric acid, food and beverage | Resistance depends on acid strength and temperature |
| SS-304 | Mild, non-chloride liquids | Generally less corrosion resistant than SS-316, so check the datasheet |
General guidance only. Always check a chemical compatibility chart for your exact chemical, strength and temperature, or ask our engineers.
Key Benefits
Correct dosing saves chemical and protects the treatment process that follows.
- Repeatable dose: each stroke delivers a set volume, so flow can be set and repeated
- Two drive types cover small flows of 1 L/h up to 1000 L/h
- Pressure up to 20 bar on solenoid and 100 bar on motor-driven pumps
- Six wetted materials to suit acids, alkalis, hypochlorite and other chemicals
- Can link with a pH analyzer or flow meter for automatic dosing
- Local engineering and after-sales support from Techno Bangla
Which Industries Use Chemical Dosing Pumps?
Chemical processing, water treatment and pharmaceutical plants are the main users of metering pumps in Bangladesh.
| Industry | What Is Dosed | Why Dosing Matters |
|---|---|---|
| Textile and dyeing ETP | PAC or alum, polymer, caustic soda, sulfuric acid | Biological treatment alone removes little colour, so chemical dosing stays central in ETP plants |
| Water treatment (WTP) | Sodium hypochlorite, coagulant, pH chemicals | Disinfection and clarification need steady, small doses in a water treatment plant |
| Boiler and cooling tower | Scale and corrosion inhibitors, biocides, acid | Inhibitors are usually dosed in proportion to make-up water. See our cooling tower |
| Pharmaceutical | pH adjusters, disinfectants, process chemicals | Tight pH and dose control supports process quality and discharge limits |
| Food and beverage | Cleaning and sanitising chemicals, pH control | PVDF and SS-316 wetted parts suit hygiene-critical duty |
| Chemical industry | Process additives and neutralising agents | Accurate feed cuts waste of costly chemicals |
| Sewage treatment (STP) | Disinfectant, coagulant, polymer | Supports discharge quality in an STP |
- ETP
- WTP
- STP
- Boiler Water
- Cooling Tower
- Textile
- Pharmaceutical
- Food & Beverage
- Chemical Plant
How to Calculate the Dosing Pump Size
A simple mass balance gives the flow you need in litres per hour.
The Formula
- Pump flow (L/h) = water flow (m³/h) × dose (mg/L) ÷ chemical strength (g/L)
- Water flow is the stream you treat, in m³/h
- Dose comes from a jar test or supplier advice, in mg/L
- Strength is the active chemical per litre of solution, in g/L
Worked Example
- ETP flow 50 m³/h and a PAC dose of 60 mg/L (an example dose from a published textile study)
- 50 × 60 = 3000 g/h, or 3 kg/h of PAC
- With a 10% solution, which is about 100 g/L, the pump flow is 30 L/h
- 30 L/h is above the solenoid range, so a motor-driven pump fits. Add a margin and check back pressure
The dose is an example only. Real doses change with effluent, so run a jar test. Under-dosing leaves pollutants in the water, and wrong dosing can upset the biological stage that follows.
Which Dosing Pump Fits Your Plant?
Choose a Solenoid Pump When
- The dose is small, up to 16 L/h
- Pressure at the injection point is up to 20 bar
- You need electronic control or flow-proportional dosing
- Space is tight and a compact unit helps
- You dose polymer, disinfectant or inhibitor
Choose a Motor-Driven Pump When
- The dose is larger, up to 1000 L/h
- Back pressure is high, up to 100 bar
- The pump runs continuously for many hours
- You want a simple mechanical design
- You dose coagulant, acid or caustic in a larger ETP
How to Choose the Right Dosing Pump
Share these details with our engineers and we will recommend a suitable model and material.
- Chemical and strength. Name the chemical and concentration. This decides the head and diaphragm material.
- Dose rate. Give the flow in L/h, or the water flow and dose so we can calculate it.
- Back pressure. Tell us the pressure at the injection point in bar, including pipe losses.
- Control method. Manual stroke setting, pulse input, 4-20 mA, or pH control with an online analyzer.
- Temperature and viscosity. Hot Bangladesh summers and warm effluent narrow the safe range of plastics, and thick liquids need a suitable pump head.
Why Accurate Dosing Matters
Too little chemical leaves colour, turbidity and solids in the water. Too much wastes chemical, adds sludge and can disturb the biological stage after it.
One industry article reports about 30 to 40% less sludge with PAC than with alum under similar conditions. Results vary by effluent, so ask for a jar test. Pair dosing with a mixing agitator for good contact.
Installation and After-Sales Support
Techno Bangla Creation supplies treatment plant equipment together with installation, commissioning and after-sales support for factories, businesses and organizations across Bangladesh.
Our team is based in Mohakhali, Dhaka. Send your chemical and dose details and our engineers will recommend a suitable dosing pump. Ask us about spare diaphragm and valve kits.
Frequently Asked Questions
What is a chemical dosing pump?
A chemical dosing pump, also called a metering pump, injects a small, controlled amount of chemical into water or process liquid. Each stroke moves a set volume, so flow can be set and repeated. ETP, WTP, boiler and cooling tower plants use it to dose coagulants, acids, alkalis, polymers and disinfectants.
What is the difference between a solenoid and a motor-driven dosing pump?
A solenoid pump uses an electromagnetic coil, is compact and suits small flows with electronic control. Ours cover 1 to 16 L/h up to 20 bar. A motor-driven diaphragm pump uses a motor and cam for larger flows and higher pressure, covering 1 to 1000 L/h up to 100 bar.
What capacity and pressure range do you supply?
Our EMEC and SEKO solenoid pumps cover 1 to 16 L/h at 1 to 20 bar. Our motor-driven diaphragm pumps cover 1 to 1000 L/h (about 1 m3/h) at 1 to 100 bar. Exact limits depend on the model, so we confirm the right size from your dose rate and back pressure.
Which pump material should I choose for my chemical?
Material depends on the chemical, strength and temperature. PVC and PP are common for caustic soda and PAC, PVDF suits sodium hypochlorite and stronger acids, and PTFE gives wide resistance. We supply PVC, PP, PVDF, PTFE, SS-304 and SS-316. Check a compatibility chart or ask our engineers.
How do I calculate the dosing pump flow I need?
Multiply the water flow in m3/h by the dose in mg/L to get grams per hour, then divide by the chemical strength in g/L to get litres per hour. For example, 50 m3/h at 60 mg/L with a 10% solution needs about 30 L/h. Confirm the dose with a jar test.
Which industries in Bangladesh use chemical dosing pumps?
Chemical processing, water treatment and pharmaceutical plants are the main users of metering pumps in Bangladesh. Textile and dyeing ETPs, boilers, cooling towers, food and beverage plants and sewage treatment plants also depend on them to dose coagulants, pH chemicals, inhibitors and disinfectants.
What maintenance does a dosing pump need?
Both solenoid and motor-driven diaphragm pumps need preventive care on the valves and diaphragm. Check for leaks, worn diaphragms and blocked check valves, and keep spare kits on hand. Service intervals depend on the chemical and duty, so confirm them on the datasheet of the exact model.
How can I get a quotation for a chemical dosing pump?
Send your chemical name and strength, required dose in L/h, back pressure and control method to our engineers by phone or email. We reply with a free quotation for your ETP, WTP, STP or water treatment equipment, and we can also advise on the matching analyzer and flow meter.
