1. Effluents with high organic loads
   Palm Oil Mill industry, Alcohol breweries (bio-ethanol production) and Farm producing large amounts of liquid manure (cattle or pigs).
2. Diluted Effluents
   Slaughterhouses, rendering plants, paper industry, sugar mills, coffee processing industries, yeast and milk processing industry’s effluents.
   

Many tropical agro-industries generate highly contaminated organic effluents (COD higher than 15.000 mg/L or 15 kg of COD/m³). They are then classified as “environmental unfriendly” due to the important contamination they generate. For these kinds of effluents BIO-TEC has developed an efficient biodigester system known as the “BIO-TEC COVERED LAGOON SYSTEM”.

The system main applications concern:
- Palm Oil Mill industry
- Alcohol breweries (bio-ethanol production)
- Farm producing large amounts of liquid manure (cattle or pigs)

The traditional system used in these industries for effluent treatment consists in a set of open anaerobic lagoons as it is the most extensive cost-efficient system as long as land is available and cheap. Usually these traditional systems are simple ponds and lack of pre-treatments, sludge removal and disposal systems.

These uncovered ponds generate biogas (half of it being methane) which is discharged onto the atmosphere contributing to the enhancement of global warming. The methane released is classified as a powerful green house effect gas and its emissions are ruled by the Kyoto Protocol. Given the high organic loads contained in these effluents, methane generation is important and the impact on global warming cannot be underestimated.

BIOTEC’s activity emphasises on three main areas

• Optimize the traditional effluent treatment system through efficient and sustainable covered anaerobic biodigestor(s) (lagoons). Ensure the impermeability of the system and the adequate effluent treatments (pre-treatment, internal mixing, sludge recirculation, biological sludge removal and post-treatment if necessary). 
• Cover the lagoons (adapting the old ones or building new ones) in order to capture the biogas generated. Biogas trapping and combustion enables the project to register as Clean Development Mechanism under the Kyoto Protocol framework. This registration allows selling Certificates of Emissions Reduction (CERs or Carbon Credits) increasing the project’s profitably. The CERs commercialization requires a good instrumentation and monitoring system, data storing and reports generation software and finally trained and qualified operators to run the system smoothly ensuring its efficiency and the project’s incomes. 
• Use the biogas for energetic purposes in the factories (or farm) or sell it (to neighbouring industries or selling electricity to the general grid).

BIOTEC is known to be a world leader in effluent treatment and biogas valorisation for Palm Oil Mills.

Examples: 

1. PALMEIRAS (Colombia 1999): 70.000 Tons of Fresh Fruit (TFF) per year. Biogas used to run a 550kW generator to supply the crude oil mill and the mechanical palmist oil extraction unit. 
   
   
2. EECOPALSA (Honduras, 2006): 100.000 TFF/year. Generation of 1,25 MW sold to the national grid. It was the first biogas project (in the Palm Oil Mill industry) in the world which has been registered as a CDM project by the UNFCCC. The whole system is locally operated by BIOTEC and remotely surveyed via the web. It generates 5 GWh and 25.000 Tons of CO2 equivalent (CERs) per year. The electricity is sold at 0,075 US$/kWh and the CERs price is 13,5 Euros/TCO2. The project validation took place in June 2006 and its first verification in April 2007. The CDM project was awarded with a Gold Standard label. 
   
   
3. INDUSTRIAS DEL ESPINO (Peru): 280.000 TFF/year (projected). The biogas is used in the thermic oil boilers for the crude oil refinery and the biodiesel refinery. The project is designed for a generation of 42.000 T of CERs per year.
   
   

 2 - Diluted Effluents

Since 1990 BIOTEC has dedicated itself in adapting the UASB reactor technology (for diluted effluent treatment) to tropical agro-industries (the so called ‘Biotec tropicalization’).

This know-how has been applied to: Slaughterhouses, rendering plants, paper industry, sugar mills, coffee processing industries, yeast and milk processing industry’s effluents.

Examples:

1. CARTONES AMERICA SA (CAME, Cali, Colombia)
   

   CARTONES AMERICA S.A. 180 T DQO/day - 30 L/s Cali, Colombia

   CAME is a factory producing 300T/d of carton and paper from recycled paper. BIOTEC activities started in 1990 when the plant only produced 80T of paper and carton per day. The first step taken was the diagnostic of the existing treatment system. Since then, both parties have worked together in order to adapt and enhance both process and effluent treatment system’s efficiency to remove contamination.
   
   The actual treatment plant is formed by a stationary sieve, rotating drums, two sedimentation tanks for paper pulp, an acidification tank, a cooling tower, an UASB reactor of 1000 m³, an aeration tank (activated biological sludge) and finally a water clarifier.
   
   Due to BIOTEC’s intervention, the fabric water consumption has dropped from 40m³ /Ton to 5m³ of water consumed per ton of paper produced. In the case of CAME the biogas produced is used in a small steam boiler.
   
   Nowadays the treated effluent characteristics meet the local environmental standards and also the World Bank standards for water quality.
   
   
2. Colanta Planeta Rica
   

   COLANTA, Planeta Rica 200 T DQO/day, 170 m3/day Department of Córdoba, Colombia

   Given the variable pH of the effluent, the sudden temperature rises and the fat & oil concentrations peaks, these kind effluents
3. require a pre-conditioning system before any biological treatment. The aim is to homogenize pH and temperature while removing the excess of fat and suspended solids.
   
   Colanta Planeta Rica is located in the Cordoba Department in the northern coastal area of Colombia. Average temperature in the region is 27,5°C. This plant processes in average 300.000 L/day of milk in order to produce powder milk, butter and pasteurized milk.
   
   During the washing process 170m³/d of effluents are generated. Their temperature oscillates between 30°-60°C with a pH ranging from 2 to 12.
   Organic load concentrations are:
   - COD: 7.000 mg/L
   - BOD: 4.000 mg/L
   - Suspended Solids: 1.300 mg/L
   - Fat and oil: 950 mg/L
   
   The plant designed and built by BIOTEC in 1999 is formed by:
   - Pumping shaft
   - Sand removal filter
   - Homogenization tank
   - Flotation tank
   - UASB reactor
   - Percolating filter
   - Secondary decanter
   The treatment plant is also provided with automatic pH control system. The area required for such treatment (including pavements and green areas) is only 200m².
   The primary sludge produced in the floatation tank is neutralised with lime and dried out through a pressing band filter. Afterwards it is used as an organic fertilizer on the surrounding farms’ soils.
   For biological sludge dehydration, the excess generated in the UASB is spread on a drying bed and water is removed by solar radiation and temperature.
   The primary physico-chemical treatment ensures that the effluent quality meets the biological requirements before entering the UASB reactor.
   The effluent discharged after treatment has got the following characteristics:
   - COD < 150 mg/L
   - BOD < 80 mg/L
   - Suspended Solids < 100 mg/L
   - Fat and oil < 50 mg/L
   The effluent discharged after treatment is transparent and odourless.
   
   
4. AGROSAN (Amaga, Colombia)
   

   FABRICA DE CAFÉ LIOFILIZADO Chinchiná, Colombia 10.000 T soluble coffee per year 10 L/s ; 2.6 T DQO/day

   This plant is located in the municipality of Amaga closed to Medellín in Colombia. In 1997 it processed 80 T/day of slaughterhouses’ wastes (guts, feathers, blood, fat, bones) and required BIOTEC’s services for the treatment of its contaminated wastewater.
   AGROSAN generated approximately 3,2 Tons of COD per day (24m³ of waste water x 150 kg of COD/m³). This high organic load was due to type of processes running in the plant (autoclaves, direct steam).
   AGROSAN decided to solve its environmental problem making firstly a shift in its internal process (using a cookers with indirect steam heating replaced the autoclaves). These actions enabled to cut off 90% of organic contamination (0,24 Tons of COD produced instead of 3,2T per day)
   Contamination was confined finally in the washing waters and the condensated water from the cookers. These effluents had a contamination of 2.000ppm of COD but an elevated concentration in ammonia (600ppm) and sulphurs (300ppm) making them odoriferous and uneasy to handle.
   
   

   AGROSAN, Amagá, Colombia 100 T of meat wastes per day

   The major environmental problem of the rendering plant was the smell generated by its activities and not really the organic load contained in the discharged remaining effluents. The smell was coming from the cookers condensates and these effluents were discharged into the nearby river.
   In order to solve the odours problems of the gaseous phase a biological BIO-TEC filter was used removing over 99% of the H2S and ammonia.
   To handle the plant cleaning waters and the condensates, AGROSAN built a mixed system:
   a) Floor cleaning waters (25m³/d) were treated in an UASB reactor after removing fat and the sandy fraction. They were “polished” through a percolating filter treatment
   b) The condensates (70m³/d) were treated in a percolating filter after a homogenization and cooling process.
   
   In 2007 AGROSAN contracted BIOTEC to handle the extension of its treatment plant as the daily production increased from 80 to 300Tons of daily waste.

   NABISCO ROYAL COLOMBIANA 6000 T of weast per year - 7 T DQO/day Palmira, Colombia	COLOMBINA S.A. 15 Ton DQO/day, 16 l/s Department del Valle del Cauca, Colombia