Introduction

In this project emphasis has given to use toilet for producing biogas. By taking the help of modern engineering and technology, this project aims to supply the biogas at the inlet of every kitchen stove in a village. It keeps our environment neat and clean. It helps in “Swachha Bharat Mission”. Through this project we can easily promote the habit of using toilet in villages and can get bio-fertilizers for our agriculture.

Block diagram

Components required

1. Transformer
2. Battery
3. Microcontroller
4. Relay
5. Seven segment display
6. Resistance
7. Variable Resistance
8. Capacitor
9. L.D.R.
10. IC NE555
11. LASER
12. Crystal oscillator
13. Motor
14. Valve
15. Pipe
16. Tank
17. Connecting wire
18. L.E.D.

Components Description

Resistor

A resistor restricts the flow of current. The resistors used here are carbon film and quarter watt type.

Capacitor

A capacitor stores electric charge. Capacitor used here is 0.01 µF and it is a mica type.

LED (Light Emitting Diode)

It is a transducer which converts electrical energy into light energy.

Transistor

A transistor amplifies current. It can be used with other components to make an amplifier or switching circuit. BC 547 is a general purpose transistor. It is an npn epitaxial silicon transistor. Its maximum collector current (DC) is 100mA.

LDR

LDR Stands for Light Dependant Resistor. LDR is a kind of variable resistor and its resistance value varies depending on the intensity of light falling on it. In dark, LDR offers extremely high resistance as high as 10 Mega Ohm but it reduces to 100 Ohms or less in bright light. So LDR is an ideal light sensor when our circuit has a dependency parameter as sun light. You can use a 5mm diameter LDR here.

NE 555

The 8-pin NE 555 timer is the most useful ICs ever made in the world. Its popular name is timer IC. It is used in many electronics projects. Just adding a few external components, it can be used to construct so many circuits. The 555 has three operating modes: Monostable mode, Astable mode and Bistable mode. It can withstand maximum supply voltage up to 16 volt. It has a maximum power dissipation up to 600mW.

Relay

Generally relay is defined as an electromagnetic switch. The relay used here is a 12 volt ice cube type.

Motor

A motor is a device which converts electrical power into mechanical power. Here we have used a small 12 volt permanent magnet type DC motor. A gear motor will be better here.

Diode 1N4007

These are general purpose diodes. These diodes have high current capability and low forward voltage drop. The average rectified output current is one ampere.

Transformer

It consists of two coils of insulated copper wire linked by an iron core. Transformers are used to step up (increase) or step down (decrease) AC voltages. Energy is transferred between the coils by the magnetic field in the core. There is   no electrical connection between the coils. Here we have used a shell type step down transformer which step downs 230 volt AC to 12 volt AC. It can  supply maximum 750 mA current.

7805 voltage regulator

The 7805 voltage regulator IC gives us a constant 5 volt DC power supply from a 12 volt rectified output voltage. So , where the rest of the 7 volt goes ? Actually, the rest 7 volt goes nowhere. It is dissipated as heat in the heat sink provided to the voltage regulator IC.

Microcontroller

A microcontroller is a compressed microcomputer which acts by getting commands through software program.

Seven segment display

It has seven light emitting diodes to display a digit from zero to nine. There is also an extra led to display the decimal point.

LASER(Light amplification by stimulated emission of radiation)

A laser is a device that emits light through a process of optical amplification based on the stimulated emission of electromagnetic radiation.

Working

When toilet is used, waste material is deposited in the tank. There is also a provision of dumping the cattle waste material in the tank. Decomposers produce biogas from the waste. From the tank, biogas is supplied to the inlet of kitchen stove through pipe. A reward point is given every time after using toilet or by dumping cattle waste in to the tank. A sensor can detect the waste flowing through the pipe and sends a signal to microcontroller. As a result, the number on seven segment display is increased by one every time. When the display value reaches at three, the valve opens automatically to delivery biogas. The valve opens due to the rotation of gear motor for a specific short interval of time. This time of rotation is due to the delay in microcontroller program. If somebody doesn’t use toilet or dump any cattle waste in the tank, then he is rewarded by a zero point which means no biogas connection to his kitchen.

Microcontroller Circuit Diagram

LDR Circuit Diagram

Power Supply Circuit Diagram

Properties of Biogas

The production of biogas is done by the anaerobic digestion of biodegradable materials like manure, green waste, sewage, plant material, municipal waste and crops. Biogas mainly consists of carbon dioxide, methane and small amounts of hydrogen sulphide, siloxanes, and moistures.

The general composition of Biogas

Methane gas- 55-70%

Carbon dioxide gas- 30-45%

Hydrogen Sulphide- 2-8%

The gases methane, carbon monoxide and hydrogen can be oxidized with oxygen. The energy which is released allows biogas to be used as a combustible fuel for purpose of heating. So, we can cook our food by directly burning it. Biogas is one of the renewable energy sources. So, it can be used for renewable energy subsidies in some parts of the world. Cleaned biogas can be upgraded to natural gas when it is changed to bio methane. Anaerobic digesters are used for producing biogas.

Advantages

1. Biogas can be produced in this way.
2. To get a biogas supply connection, every villager will show interest to use toilet. So, a clean environment can be expected.
3. After extraction of biogas, the residual waste from the tank can be used as a better bio-fertilizer for agriculture.
4. This helps in clean India program.

Program code for 8051 microcontroller

#include<reg51.h>
sbit SW1=P0^0;
sbit pin1=P1^0;
void UpCount(void);
void Delay(void);
unsigned char Count;
unsigned char Pattern[10]={0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8,0x80,0x90,0xC0};
void main(void)
{
Count=0;
SW1=1;
pin1=0;
P2=0xC0;
while(1)
 {
  if(SW1==0)
		
   {
     UpCount();
     Delay();
     while(SW1==0);
		 Delay();
     P2=Pattern[Count];
		 
		 if(Count==2) pin1=1;		 //display value 3 and pin 1 high So,valve opens
		 Delay();// for this time pin1 becomes high
		 pin1=0;// this helps to trigger the timer ckt if timer ckt is used  to rotate //the motor
		 
                      
		 if(Count!=2) pin1=0; // valve remains opened from display value 4,5,6,7,8,9, 
		                     //before display value 0, valve closed                       //mannually,
		                     // valve remains closed for diplay value 1,2
		 
	 
   }
 }
}
void UpCount(void)
{
	
	
 Count++;
 if(Count==10) Count=0;
	
}
void Delay(void)
{
	int j;
	int i;
	for(i=0;i<10;i++)
	  {
		for(j=0;j<10000;j++)
		  {
			}
		}
}

Contact:

Er. Anil Kumar Prusty.

Phone No: +91 9861004895