Technoplast - Nairobi

7/27/2019 Technoplast - Nairobi

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ENERGY AUDITat

Technoplast Ltd.Nairobi

on behalf of

Kenya Association of Manufacturers

by

Lean Energy Solutions, Nairobi



Equipments at Technoplast



Monthly Electricity Consumption (10-11)

MONTH

ELECTRICITY (KENYA POWER) Specific

energy

costKSh/kWhDemandkVA PowerFactor ConsumptionkWh Total BillKSh CostKSh/kWh

Load

Factor,%

JUL '10 137 0.98 35,542 496,642 13.97 37 13.97

AUG '10 151 0.97 61,222 801,321 13.09 58 13.09

SEP ,10 146 0.97 62,481 14,434 13.03 61 13.03

OCT '10 144 0.97 66,236 862,021 13.01 66 13.01

NOV '10 142 0.96 64,269 885,485 13.78 65 13.78

JAN '11 170 0.75 55,680 786,364 14.12 61 14.12

FEB' 11 144 0.97 60,705 879,523 14.49 60 14.49

MAR '11 161 0.99 54,894 877,203 15.98 48 15.98

APR '11 165 0.98 64,154 1,084,190 16.90 55 16.90

MAY '11 201 0.97 56,999 1,032,488 18.11 41 18.11

JUN '11 201 0.98 77,454 1,407,135 18.17 55 18.17

Total 659,636 9,926,807 15.05



Approximate Break-up of Electricity

Consumption

Pulverisers58.6%

Roto MouldingMachines

17.9%

Cooling Tower Fan

& Pumps11.4%

Others12.1%



Control Operation of Cooling Tower Fans

Existing Condition: Cooling water is used for cooling Pulverizing machines &

recycled plastic extruder. 1 no. primary pump circulates water

from the hot well to cold well through the cooling tower. 1 no.

secondary pump circulates water from the cold well to the plantand back to the hot well. Both pumps and fan are operating

continuously.

The cold well temperature in the cold well during normal

production time was observed to be varying from 23°C. Duringshift changeover, the cold well temperature was 17.5°C.



Control Operation of Cooling Tower Fans

Recommendation: Install temperature controller for switching the cooling tower

fan ON or OFF depending on the cold well temperature. It is

recommended that the fan be switched ON when the cold well

water temperature is 30°C and switched OFF when thetemperature is 25°C. Considering the Nairobi ambient

conditions, it is likely that the cooling tower fan will remain

OFF for about 50% of the time.

Savings: 20,000 kWh/annum i.e. KShs 300,000 per annum

Investment for Temperature Controller: KShs 60,000.

Payback Period: 3 months



Eliminate Primary Pump in Cooling Tower

Existing Condition: 1 no. primary pump circulates water from the hot well to cold

well through the cooling tower. 1 no. secondary pump

circulates water from the cold well to the plant and back to the

hot well. Both pumps and fan are operating continuously.

Recommendation:

Connect the return line of secondary pump to the top of cooling

tower and eliminate the primary pump.

Savings: 15,000 kWh/annum i.e. KShs 225,000 per annum

Investment: Negligible

Payback Period: Immediate



IDO Composition & Calorific Value

IDO Composition & Calorific Value

Carbon 83.7 %

Hydrogen 13.1 %

1.8 %

Oxygen 0.5 %

Nitrogen 0.7

Ash 0.02

Moisture 0.25 %

Higher Heating Value of fuel 10700 kcal/kg



Indirect Efficiency Oven No. 1%O2 in Flue Gas (before APH) 9.80 %

%CO2 in Flue Gas (before APH) 7.25 %

CO in Flue Gas (before APH) 35.00 ppm

Flue Gas Temp. (Tf ) 226.00 °C

Ambient Temp. (Ta) 22.00 °C

Humidity of air 0.010 kg/kg of dry air

Specific Heat of Flue Gas (Cp) 0.24 kcal/kg/°

Specific heat of fly ash 0.16kcal/kg°C

Calculations

Stoichiometric air requirement 14.05 kg of air/kg of fuel

Excess air 87.50 %

Actual air supplied 26.35 kg of air/kg of fuel

Unburnt Carbon in Ash 0.00 kg/kg of fuel

(1) Heat Loss Due to Dry flue Gas 14.87 %

(2) Heat Loss due to evaporation of water formed due to H2 in

fuel 7.43 %

(3) Heat loss due partial conversion of C to CO 0.02 %

(4) Heat loss due to moisture in air 0.23 %

(5) Heat loss due to moisture in fuel 0.02 %

(6) Heat Loss due to radiation & convection (assumed) 2.00 %

Oven Efficiency = 100 - (1+2+3+4) = 75.43 %



Summary of Energy Efficiency of Ovens

& Expected Savings by Improved Sealing

(with door closed)

Roto

Moulding

Oven

Existing

Efficiency

Expected

Increase in

Efficiency

Remarks

Oven1 75.4% 2.2% Heavy leaks

near burner duct

Oven 3 68.5% 11.6%

Oven 4 71.7% 10.6%

Overall energy efficiency including door opening losses, heating of moulds from cold etc. is likely to be 10% to 40%, also depending on

the size of tanks.

Plug leakages and save about 33,000 litres of IDO per annum i.e. KShs

2.90 million, investment is minor.



Wood or Agro Briquette Gasification

Down Draft Gasifier Producer Gas Burner



Basics of Biomass Gasification

Calorific value of Biomass Briquettes : 3800 kcal/kg

Conversion efficiency: 60%

Calorific value of Producer Gas: 1100 -1200 kcal/m3

Quantity of producer gas produced: 2.0 m3/kg biomass

Existing Condition:

IDO is fired in the Roto Moulding Ovens for heating moulds

ECO: Replace IDO in Roto Moulding Ovens

with Gasified Wood or Agro Briquettes

Proposed:

Substitute IDO with Producer Gas produced in Biomass Gasifiers



Existing IDO consumption: 330,000 litres/annumPrice of IDO: Kshs 88 per litre

Cost of IDO: KShs 29 million per annum

Expected agro briquette consumption: 1.5 million tonsPrice of agro briquette: Kshs 14 per kg

Cost of agro briquettes: KShs 21 million per annum

Saving: KShs 8 million per annum

Investment for Gasifier, gas piping & burners: KShs 30 million

Payback period: 4 years

ECO: Replace IDO in Roto Moulding Ovens

with Gasified Wood or Agro Briquettes

Documents

Technoplast - Nairobi