WKJT Engineering & Construction (PVT) Ltd

Why Choose WKJT Biogas Units?

We don't just build tanks; we engineer sustainable energy solutions. Our units are designed based on the NERDC 'Semi-Dry Process' technology to ensure maximum gas production and safety.

NERDC Certified Tech

Officially licensed by NERDC to construct 'Semi-Dry Process' units highly efficient for Sri Lanka.

Premium Materials

SLS Certified PVC pipes (Type 600/1000), high-gauge Stainless Steel, and reinforced concrete for 20+ years lifespan.

Registered Company

Registered Private Limited Company (PV 00337743). Ensures accountability and after-sales support.

How We Work (Biogas Process)

Site Inspection

We visit your location to identify the best spot and system type.

Quotation & Design

We provide a detailed estimate and construction plan.

Construction

Our skilled team builds the unit using high-quality materials.

Handover & Training

We test the system and train you on how to use it safely.

How Does Biogas Work?

Biogas is a type of biofuel that is naturally produced from the decomposition of organic waste. When organic material, such as food scraps and animal waste, breaks down in an oxygen-free environment (anaerobic conditions), a blend of gases primarily methane and carbon dioxide, is released.

At WKJ Engineering, our units are designed to capture this gas efficiently so you can use it for cooking, lighting, and heating.

1. Inlet: Feed waste mixed with water.
2. Digester: Bacteria break down waste (Fermentation).
3. Gas Holder: Collects Methane gas.
4. Outlet: Releases organic liquid fertilizer.

WKJT Biogas Production Process

Available Models

Stainless Steel Unit

Compact & Rust-proof. Ideal for modern homes with limited space.

✅ Compact Design
✅ 100% Rust Proof
✅ Quick Installation

Concrete Fixed Dome

Underground construction. Best for long-term usage (20+ Years).

✅ Underground (Saves Space)
✅ High Gas Production
✅ 20+ Years Lifespan

Fiberglass/Plastic Unit

Portable solution. Suitable for semi-urban areas and farms.

✅ Portable & Movable
✅ Leak Proof
✅ Low Maintenance

Industrial Plant

Large scale stainless steel tanks for factories and large farms.

✅ High Capacity (20m³ - 100m³)
✅ Electricity Generation Capable
✅ Waste Management Solution

Choose Your Portable Unit

Plastic Biogas Unit

Cost-Effective Solution

Material: High-Quality Plastic
Lifespan: 10 Years
Capacity: 1m³ - 3m³
Biogas Burn: Normal Pressure

Get Quote

Fiberglass Biogas Unit

Premium Long-Lasting

Material: Reinforced Fiberglass
Lifespan: 20 Years
Durability: High Strength
Capacity: 1m³ - 5m³
Biogas Burn: Normal Pressure

Get Quote

What's Included in Our Package?

🏗️ Materials

Cement, Sand, Metal, Bricks, Steel Bars (10mm/8mm)

🔧 Plumbing

PVC Pipes (Types 600/400), Elbows, Sockets, Ball Valves

⚙️ Equipment

Biogas Stove, Gas Holder, Binding Wire, Polythene

👷 Labor

Excavation, Construction, Plumbing, Commissioning

Request a Quote

Our Construction Process

High-quality construction standards maintained at every step.

Base Concrete & Foundation

Steel Reinforcement

Tank Construction

Inlet Chamber & Finishing

Generate Electricity from Biogas

Why use a Biogas Generator?

Did you know that the biogas produced from your daily waste can be used to generate electricity? By connecting a specialized Biogas Generator (1kW - 5kW) to your WKJT Biogas unit, you can power your home appliances for free.

Free Electricity
Cut down your electricity bill by using your own homemade gas to run generators.
100% Eco-Friendly
Zero carbon emission. A clean energy source that protects the environment.
Power Backup Solution
Perfect solution during power cuts. Keep your lights and fans running.

Note: We can guide you on choosing the right generator conversion kit (By Biogas) suitable for domestic usage.

Other Biogas Applications

Biogas Lamp

Light up your home using free biogas energy. These special lamps work directly with methane gas pressure, providing bright illumination without electricity.

Zero Electricity Cost

Instant Water Heater

Enjoy instant hot water for bathing and washing. Our Biogas Water Heaters are designed to operate safely and efficiently with domestic biogas units.

Hot Water on Demand

Benefits of Installing a Unit

Free Cooking Gas

Reduce your LPG bills to zero. A standard domestic unit produces enough gas for daily cooking needs.

Organic Fertilizer

The liquid output (slurry) is a high-quality organic fertilizer, rich in Nitrogen for your crops.

Waste Management

Solve your garbage disposal problem hygienically. No more bad odors or flies from open waste.

Technical Engineering Data

1. Gas Production (Per 1kg Waste)

🐐 Goat Waste 160 Liters
🍲 Food Waste 150 Liters
🐖 Pig Waste 75 Liters
🐄 Cow Dung 35 Liters
🚽 Human waste 70 Liters

2. Temperature Effects

26°C - 32°C: Normal Production (Ideal for Sri Lanka)

> 50°C: CRITICAL (Bacteria dies)

3. HRT (Retention Time)

How long waste should stay in the tank.

Feed	Days
Cow Dung	30-40 Days
Food Waste	20-30 Days
Mixed Feed	25-35 Days

Generator Sizing Guide (Technical)

Technical breakdown of gas requirements for electricity generation.

Connection: Digester → Scrubber → Generator

Generator(kW/Hour)	Gas Need (Hr)	Digester Size	Cow Dung (Daily)
1 kW	0.6 m³	8 – 10 m³	25 – 30 kg
3 kW	2.0 m³	20 – 25 m³	70 – 90 kg
5 kW	3.5 m³	35 – 45 m³	120 – 150 kg
10 kW	7.0 m³	70 – 90 m³	250 – 300 kg

Optimizing Biogas Production

Temperature plays a critical role in biogas efficiency. Maintaining the correct temperature ensures optimal gas production.

20°C - 25°C

Biogas Production is slow

Bacteria activity slows down significantly.

Low Temp

26°C - 32°C

Biogas Production is Normal

Optimal range for standard digestion.

Recommended

37°C - 46°C

Biogas Production is High/Fast

High efficiency but needs control.

High Efficiency

Above 50°C

CRITICAL

Bacteria may die. Production stops.

Danger Zone

The Challenge: Cold Climates

In regions like Nuwara Eliya, Kandy, Bandarawela & badulla, low environmental temperature causes the water inside the unit to cool down.

Result: Gas Production Slows Down

WKJT Solution

Our Solution: Heat Exchanger

We install a specialized Internal Heat Exchanger coil within the plant. This circulates warm water to maintain the optimal temperature (35°C - 45°C ).

Result: Fast & Continuous Gas Production

Scientific Composition & Prohibited Materials

Biogas Chemical Composition

Biogas is a mixture of gases produced by the breakdown of organic matter. High Methane content ensures a strong blue flame.

Methane (CH₄) 55% - 70%

Carbon Dioxide (CO₂) 30% - 40%

Hydrogen Sulfide (H₂S) 1% - 5%

Other Gases (H₂, N₂, NH₃) Trace Amounts

Materials to STRICTLY AVOID

Never put these into the digester:

Soap Water (සබන් වතුර)
Pesticides (කෘමිනාශක)
Metal / Glass (වීදුරු/යකඩ)
Sawdust (ලී කුඩු)

Laundry Water (රෙදි සෝදන වතුර)
Polythene / Plastics
Sand / Soil (වැලි/පස්)
Coconut Shells (පොල් කටු)

Concrete Underground Unit Capacities

Usage Type	Digester Capacity
Domestic (නිවාස සඳහා)	8,000L(8m³) - 12,000L(12m³)
Farm / Agriculture (ගොවිපල)	15,000L(15m³) - 25,000L(25m³)
Hotel / Restaurant (හොටෙල්)	30,000L(30m³) - 40,000L(40m³)
Industrial (කර්මාන්ත)	60,000L(60m³) - 80,000L(80m³)
Electricity Generation (විදුලි ජනක)	100,000L(100m³) - 500,000L(500m³)

Energy Comparison: LP Gas vs. Biogas

Understanding the real energy value of your Biogas

1 kg LP Gas

= 46 MJ Energy

High intensity energy source

Equivalent To

2100 Liters Biogas

≈ 2.5 kg Biogas

Useful cooking equivalent

Scientific Breakdown

Energy Content (LPG):

1 kg LP Gas = 46 MJ

Energy Content (Biogas - 60% Methane):

21 - 22 MJ per m³ (1000L)

Practical Memory Rule:

1 kg LPG ≈ 2.1 m³ of Biogas

Practical Savings

12.5 kg LP Gas Cylinder Equivalent

≈ 5,500 – 6,000 Liters Biogas

Average Family Daily Cooking Need

≈ 800 – 1,000 Liters / Day

* All energy calculations are based on standard 60% methane concentration for Biogas.

Practical Usage: LP Gas vs Biogas

Direct substitution for your daily cooking needs.

How much Biogas do you need?

1kg LP Gas ≈ 2.1 m³ (2100 Liters) Biogas

The energy equivalent for standardized household use.

12.5kg LP Cylinder ≈ 5,500 - 6,000 Liters Biogas

Replace your entire monthly gas cylinder with free biogas.

Daily Cooking Needs ≈ 800 - 1000 Liters/Day

Based on an average Sri Lankan family requirements.

Technical System Overview

Complete Biogas Plant with Heat Exchanger System

This diagram illustrates the complete cycle: from organic waste input to the Anaerobic Digester (with internal heating coils), leading to Biogas Upgradation, CHP Engine operation, and Waste Heat Recovery.

Internal Heat Exchanger Maintenance

Why Cleaning is Important?

Over time, the internal coils can accumulate residue, reducing heat transfer efficiency.

Before Cleaning: Residue blocks heat transfer (Slow Gas Production).
After Cleaning: Maximum heat efficiency (Fast Gas Production).

We provide full maintenance support.

Start Your Energy Journey Today

Call 0763811765

* Site inspection fees may apply depending on the location distance.
(දුර ප්‍රමාණය අනුව ගමන් වියදම් ගාස්තු අය කරනු ලැබේ)

Biogas Solutions