Industrial Wastewater treatment process

Industrial Wastewater treatment process Presented by Dr Trzcinski P. Antoine, Senior Research Fellow & Safety Officer

Prof. Ng Wun Jern, Exec-Dir NEWRI, Dean & Professor,

College of Engineering, NTU

4th September, 2013

Presentation outline Introduction to NEWRI Nature of industrial wastewaters Impacts of discharges Industrial wastewater treatment - pre-treatment units - Aerobic processes - Anaerobic processes • Case studies: slaughterhouse and palm oil milling • Case studies: sugarcane vinasses • • • • •

Connecting with NEWRI

Project sampling: •

Application of Water Treatment Process in Candirejo Village, Yogyakarta Special Province, Indonesia

•

Potential for the Conversion of a Waste Stabilisation Pond System into an Integrated Pond Wetland System for the Treatment of Wastewater in Dongkok Wetland, Laos

•

Mitigation of Pollution in Kandy Lake and Mid Canal, Sri Lanka

•

Improving the Life Quality of the Cibuntu Community with Biogas, Indonesia

•

Fate of Arsenic in Waste Generated from Arsenic Removal, Nepal

•

Development of Clean Water and Sanitation Systems at Inle Lake, Myanmar

•

Energy from organic waste from small communities, India

NEWRITech

“Reaching out to industry and monetizing R&D ”

RTD +FS

RTD +FS

Impacts of industrial wastewater discharges in Asia

• 785 million people have no access to safe water

• Coastal waters supporting fisheries and tourism industries, damaged. • Tansui River (Taiwan): pesticides and heavy metals (Liu & Kuo, 1988) • Nam Pong River (Thailand): polluted by the pulp and paper industry (Jindarojana, 1988) • Buriganga River (Bangladesh): polluted by tanneries • Koayu River: Cryptosporidum oocysts and Giardia cysts from piggery wastewater (Hashimoto & Hirata, 1999) • Hainan Island (Southern China): sugar refineries, paper mills, shipyards, and fertilizer plants  red tide in Houshui Bay (Du,1995).

Key pollution factors • Temperature • pH (acidic/alkaline) • Suspended solids (TSS1. Less than 3 biodegradable  biological process likely to be successful

Anaerobic – aerobic treatment

Ng, W. J., Industrial wastewater treatment, London, Imperial College Press


How to tackle Oil and Grease ?


Oil and grease trap in a POME refinery IWTP

Baffle plate O&G trap inserted into a surface drain leading to the IWTP at a palm oil refinery. • Effective • but not enough to meet discharge limits


Oil and grease trap in a POME refinery IWTP


Baffled tank O&G trap at palm oil refinery provides for more quiescent conditions to allow for greater removal of O&G than what is possible with the simple trap shown

Reactor Configurations • continuous-flow stirred-tank reactor (CFSTR) • plug flow reactor • batch reactor

Anaerobic process Anaerobic filter Anaerobic lagoon Anaerobic digester UASB Anaerobic SBR

Aerobic process Activated sludge process Aerobic SBR MBR

SLAUGHTERHOUSE WASTEWATER

very strong wastewater stream if blood is not adequately segregated (BOD > 100 000 mg/L)


• BOD:COD ratio  easily biodegradable wastewater, • Low BOD:N ratio  need for nitrification and possibly even nitrogen removal • High SS

• The wastewater can be expected to contain some O&G + blood and fine SS  a scum results. • Good housekeeping • O&G + blood  high aeration requirements

Pre-treatment: coagulationflocculation followed by DAF


Aerobic biological treatment options: activated sludge process, oxidation ditch, and sequencing batch reactor.

• if space is available: lagoons • Screens — coarse and possibly fine screens. DAFs may not be used then. • Anaerobic lagoons • 2 stages (0.7 kg BOD/ m3 lagoon volume and 0.2). Typical BOD removal by the first and second: about 65% and 60%, respectively

anaerobic lagoons  aerated lagoon (0.07 kg BOD/m3, HRT ~ 2–3 days, 80% BOD removal


PALM OIL MILL AND REFINERY WASTEWATER

Palm oil FFB receiving bay. Oil press  wastewater treatment plant.


Palm oil mill effluent (POME) characteristics • High organic content, thick brownish appearance. • Low pH • Nutrients deficient (BOD:N:P at 100:3.5:0.5)  Typically treated anaerobically first (lagoon 1 at 60 days HRT, lagoon 2 at 40 days)  Effluent is typically 200-1000 mg BOD/L. • 60 tonnes FFB/h mills  2–4 ha.

Energy positive process: • 2 stages anaerobic digester (HRT > 15 days, 80% BOD removal, OLR ~5 kg VS/m3.day). • Biogas yields ~ 900 L/kg


•anaerobic lagoons and digesters  aerated lagoons. • Sludge residence times of 20–30 days and MLSS ~ 5000 mg/L. • Effluent BOD: 50–100 mg/L Ng, W. J., Industrial wastewater treatment, London, Imperial College Press

Aerated lagoon treating POME. • rectangular-shaped lagoons • > 2 surface aerators

Sugarcane industry - Vinasse-Dependence on Raw Material and Ethanol Process Surplus bagasse Bagasse Sugarcane

Reception and cleaning

Cogeneration system

Clear juice

Steam and power for the process

Sugar factory

Preparation

Surplus electricity

Distillery

Evaporation

Fermentation

Recycled yeast

Syrup Milling

Dilution

Centrifugation

Treatment of yeast

Juice Primary treatment

Cooking

Destilation

Cristallization

Rectification

Centrifugation

Hydrated ethanol

Yeast Drying

Sulfurizing

Liming

Dehydration

Molasses Drying

Heating Vinasse Decanting

Filtration Filter cake

Clarified juice

Filtered juice

Sugar

Hydrated ethanol

Anhydrous ethanol

Dry yeast

Sugarcane industry - Vinasse-Dependence on Raw Material and Ethanol Process

When obtained straight from sugar cane juice –Light brown color with 20,000 – 40,000 mg/l solid content

When obtained from sugar cane molasses: –Black-reddish color with 50,000 –100,000 mg/l solid content

A 420,000 L/day ethanol distillery produces a volume of vinasse equivalent to the wastewater of a city with population of 768,000 people

A cluster of three anaerobic digesters used at a sugar mill


Anaerobic lagoons


Two anaerobic lagoon cells under construction. Note that the lagoon cells had not been lined nor had the bunds been fully constructed. The reinforced concrete inlet and outlet works had yet to be constructed.

Comparative Vinasse Composition

Source: Barreto de Menezes, T. J., Etanol, o Combustible do Brasil (Ethanol, Brazil's fuel, in Portuguese language),1980, Editora agronomica Ceres Ltda, Sao Paulo, Brasil

pH between 4 and 5 BOD content between 10,000 and 50,000 mg/l

Assumption

Example

Operation temperature

35-40°C

BOD conversion

90%

Vinasse BOD

50,000 mg BOD/L

Methane yield

600 L/kg BOD (250-900)

Methane content

60% (55-70%)

Biogas energy value

5.5 kWh/m3

HRT

40 days

Distillery Production Data

Example

Ethanol production, l/year

37,850,000

Vinasse production, l/l ethanol

12

Days/year

150

AD Production Data

Example

Digesters volume, m3

121,000

Biogas production rate, m3/day

81,756

Methane production rate, m3/day

49,053

Power generated

7.3 MW

Vinasse effluent

5,000 mg BOD/L

The NEWRI

Community

Some 400 researchers. Pan NTU.

Be a part of the solution