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Modern wastewater treatment plant at a modified starch industry by Papop

Papop completed a modern and state of the art wastewater treatment plant at a modified starch industry. In this project, Papop undertook detailed design, construction, equipment installation, commissioning and startup. Project duration was 12 months from start to hand over.

Modified starch industry wastewater treatment plant by Papop

Before we proceed to the wastewater treatment plant, first we shall have a good understanding of the modified starch industry. First the raw materials could be starch from tapioca, rice, sticky rice or corn. Modifies can be applied as a important ingredient in various food industries.

Foreign countries typically use corn starch to produce modified starch. However, Thailand and Asian countries prefer to use tapioca starch, since it has its own uniqueness and has non-GMOs.  Slowly tapioca modified starch is becoming widely accepted worldwide.

Wastewater generated from the production of modified starch has varying characteristics depending on the raw materials and products/processes design. The wastewater is often found to have moderately high concentration of organic matter (i.e. COD and BOD) and Total Kjeldahl Nitrogen (TKN) or some kinds of ions such as sodium (Na+). This is due to the usage of some chemicals to produce the desirable products.

The design of wastewater treatment plant for this industry have to consider the wastewater characteristics on a case-by-case basis, since each industry may have totally different wastewater characteristic. In this project, the wastewater has moderately high COD (Biochemical Oxygen Demand), Total Dissolved Solid และ TKN (Total Kjeldahl Nitrogen). Hence, the process will involve chemical precipitation, anaerobic (UASB) and followed by activated sludge process.

First the wastewater is collected and stored in an equalization tank which also acts like an acidification tank. This is where the large molecular organic constituents will turn into smaller molecular organic constituents. Afterwards, the effluent from the equalization tank will go to the chemical precipitation process to remove suspended solids and dissolved solids. The chemical sludge from this process will be treated at the filter press.

Chemical precipitation process

The effluent from chemical precipitation will be pumped to UASB tank which is designed as a rectangular concrete tank. Inside this tank, granular sludge will degrade organic matter to produce biogas. The wastewater flows through the sludge blanket at the bottom of the tank and effluent will leave via the weir at the top. The produced biogas quantity is quite small, so it is not economically feasible to apply it. Hence, the factory installs a biogas flare to oxidize all biogas.

UASB Tank by Papop
UASB Weir Papop
Biogas flare

The effluent from the UASB tank passes through the aeration tank (activated sludge process) which is designed to also remove nitrogen using biological activity. Afterwards, the clear effluent goes through the sand filtration process to remove any remaining suspended solids before it is discharged to the nearby watercourse. The excess sludge is delivered to the screw press.

Aeration tank Papop
Sedimentation tank
Sand filter

If you are interested in a modern wastewater treatment plant like this one, please feel free to contact us at Papop LINE: @papop or Email: info@papop.com. Our friendly staff will always be happy to serve you in due course.