COMPANY PROFILE
1 . Name : Hai Duong Porcelain Company
2 . Address : Pham Ngu Lao str Hai Duong City , Vietnam
3 . State : State Owned Company
4 . Capital : Government 10 billion vnd , Bank 3 million vnd
5 . Annual sales : 3 million US $6 . Product : Porcelain
7 . Production : 14 million pieces/year
8 . Employee : 955
9 . Working hour : 7.00 ～17.00
10 . Energy consumption

CONSUMPTION
2001

2002

FACILITY

Diesel oil (kg)25,22925,473Generator

L P G (ton)

251.8

799.1

Porcelain firing

Natural gas (m3)647,623

594,160

Insulator firing

Coal (ton)

4,407

4,736

Porcelain firing

1

PRODUCTION PROCESSDETAILPROCESSFACILITY

Raw material

Quartz , feldspar , kaolin , clay etc

Crushing

Coarse , medium

Jaw crusher , roll mill

Blending

Fine crushing with water

Ball mill

Adjustment

Sieving , de-ironing , kneading ,Filter press , de-airing machine

Forming

Jiggering , casting

Jiggering machine , plaster mould

DryingRemove moisture

Dryer

FiringGlossy , decoration

Tunnel , shuttle , roller hearth

Inspection

Warp , color , pinhole , crack etc

DeliveryPacking

21MAIN FACILITY AND CAPACITY

FACILITY

ENERGYCAPACITY

Power equipment

Electricity

90,755 kw

BoilerCoal

3.2 ton/hr

Tunnel kiln

Coal

1 million pcs/mon

Decoration kiln

Electricity

496 pcs/hr

Decoration kiln ( R H K )LPG

1,230 pcs/hr

Shuttle kiln ( 10 m3 )LPG

3,500 pcs/time

Shuttle kiln ( 4.7 m3 )LPG

1,800 pcs/time3

SPECIFICATION OF FIRING FACILITY

TUNNEL KILNROLLERHEARTH KILNSHUTTLE KILN
10m 34.7m3

Length (m)86.720－－Inside width (mm)

1300

1150

2070

1550

Effective height (mm)

1250

260

1300

1100

Maximum temperature (℃)

1350

915

1350

1350

Reduction

Oxidization

Reduction

Reduction

Firing atmosphere
Number of burners (one side)

23

Pushing speed of kiln car

62 min/car

Fuel

Producer gas

Composition

CO 24 %

1830.2 m/min

1024 hr/time

19 hr/time

LPG

LPG

Butane60 % Propane40% Butane60 % Propane40%

LPG
Butane60 % Propane40%

1,440 /m3

11,000 /kg

11,000 /kg

11,000 /kg

13,820,730m3

38kg/hr

556kg/time

260kg/time

Number of cars inside kiln

4240slabs/row×3rows－－Length (mm)2000

500/slab－－

Width (mm)1300

380/slab－－

Effective height (mm)

1310

260－－

Calorific value (kcal /)Consumption
Kiln car42

SURVEY AND ADVICE ITEM FOR ENERGY CONSERVATIONEFFECT (ENERGY CONSERVATION)INVESTMENT

Tunnel kiln
Not necessary

Heat balance
Reduce radiation heat loss from kiln surface Coal = 474 ton/year 21,400 us $/year

10,000 us$

Reduce heat loss of combustion exhaust gas

Coal = 237 ton/year 10,700 us $/year

Not necessary

Replace sand for sand seal and optimizing
the volumeTemperature difference small

3,000 us$

Provide gap between sagger and car top

Decrease temperature difference between
top and bottom

5,000 us$

Maintain sagger height for kiln car

Stabilize gas flow and temperature insidekiln , improve yield

Not necessary

Install kiln exit door

Stabilize atmosphere and temperature ofmaximum temperature zone , improve yield

1,000 us$

Extend pre-firing hour from entrance
before reduction atmosphere zone

Decrease temperature difference between
top and bottom , improve yield

Not necessary

Roller hearth kiln
Increase kiln pressure to positive

LPG = 6.6 ton/year 2,500 us $/year

Not necessary

Introduce biscuit firing process

Improve quality of ware

Not necessary

Decrease temperature difference between
top and bottom , improve yield

5,000
us$ 50,000 5us$

Shuttle kiln
Install high speed type burner or introduce
high speed type kiln

HEAT BALANCE OF KILNTUNNEL KILN

I nput heat

Fuel combustion heat
Heat carried by pre-fired goods and sagger
Heat carried by pre-fired goods
Heat carried by sagger
Heat carried by kiln car
Heat carried by the refractory
Heat carried by iron part
Total

Outp ut hea t

Heat carried by pre-fired goods and sagger
Heat carried by fired goods
Heat carried by sagger
Heat carried by kiln car
Heat carried by the refractory
Heat carried by iron part
Heat carried by cooling air

Effe cti ve heat

Heat carried by combustion exhaust gas

Calorific value
7387.2×103
0%
99.80

Calorific value
836.0×103
3.4

00
13.1

0

2.1
1.3

0.4
0.2

12.3
0.8
7400.3×103

100

839.4×103

100

8.0
3.1
4.9
144.4
141.1

0.2
0.1
0.1

23.8
6.2
7.62.83.30.1
23.3
24.0

295.0
442.0

35.1
52.7

1732.6
1772.83742.5

Total
Effective heat per ton of fired goods

7400.3×103
457.5×10 3

Heat required for heating sagger
Heat efficiency for fired goods only
Heat efficiency for fired goods including sagger

%
99.6

00.2
0.1
0.1

Heat loss due to radiation and others

Heat required for firing the pre- fired goods
Effective heat per ton of fired goods including sagger(Unit : kcal/t)
ROLLER HEARTH KILN

457.5
1188.5731.0
6.2 %16.1 %0.21.90.9

2.0
1.9

50.5
10078.6
9.4100839.4×103
308.2 ×10 3308.2
395.9
87.7
36.9 %

647.4 %

3

Effective heat

EFFECTIVE HEAT OF SHUTTLE KILN

Effective heat per batch of fired goods

10m3 SHUTTLE KILN

4.7m3 SHUTTLE KILN

321.9×103 kcal/batch

165.6×10 3 kcal/batch

Heat required for firing the pre-fired goods

321.9

165.6

Effective heat per batch of fired goods including slabs

748.6

384.2

Heat required for heating slabs

426.7

218.6

Heat efficiency for fired goods only

5.3 %5.8 %Heat efficiency for fired goods including heating slabs

12.2 %

13.4 %

7

ITEM OF ENERGY CONSERVATION
Response of HAPOCO: discussed by Management
Board but not implemented yetⅠ．Tunnel kiln

(1) Reduce radiation heat loss from kiln surface
Action : Cover ( 50 mm ) kiln surface by ceramic fiber or board (only for firing zone)
Effect : Energy conservation

10 % ( according to the actual results and experience)

Fuel ( coal ) consumption : 4,736 ton / 2001year
Unit price of coal : 700,000 vnd / ton
Energy consumption : 4,736 ×0.1 × 700,000 = 33,152 × 104 vnd / year
=21,400 us $ / year

Ceramic fiber orboardProduct( Thickness 50 mm )BurnerKiln car84

Response of HAPOCO: implemented( 2) Reduce heat loss of combustion exhaust gas
Action : Maintenance of sand for sand seal and suitable kiln pressure
Effect : Energy conservation

5 % (According to the actual results and experience)

Fuel ( coal ) consumption : 4,736 ton / 2001year
Unit price of coal : 700,000 vnd / ton
Energy consumption : 4,736 ×0.05 × 700,000 = 16,576 × 104 vnd / year
=10,700 us $ / year

Response of HAPOCO:
implemented(3) Replace sand for sand seal and optimizing the volume
Action : Replace sand for sand seal
Material : Shamott or sandGrain size : 3 ～ 5 mmφ
Charge : 80% of sand channel
No, of charge : once a day from exit to entrance
Sieving : pass through small size

Effect : Cut off air from under car to inside of kiln , save fuel ,temperature difference small

9Kiln wall
Product60 mm
Kiln car
Sand channel

Car apron

Sand channel

105Response of HAPOCO:(4) Provide gap between sagger and car top

implemented

Action : Laying bricks between sagger and car top
Effect : Increase temperature of center and lower shelve ,decrease temperature difference between t op and bottom

SaggerBrickCar top

11(5) Maintain sagger height for kiln car
Action : Adjust height of same level

Response of HAPOCO:
Finished

Effect : Stabilize gas flow and temperature inside kiln , improve yield126

(6) Install kiln exit door

Response of HAPOCO: sealed by high pressure air

Action : Install door
Effect : Prevent to intrude cold air into the kiln , stabilize atmosphereand temperature of maximum temperature zo ne , improve yield(7) Extend pre-firing hour from entrance before reduction atmosphere zone
Action : Change 2 ～3 burners (each side) of reduction burner to oxidation burner
Effect : Decrease temperature difference between top and bottom , improve yield

Response of HAPOCO: could not changed, tomaintain temperature and products quality

13(℃)
1200

Heat curve(mmH 2 O)
0.4
0.3
0.2
0.1
0- 0.1
- 0.2
- 0.3
- 0.4

Kiln pressurePressureTemperature

1000800
600
400Oxidization

Reduction

200Time (h)InletExhaustWaste heat

FFOO

R ROOO O × × R R R R R R R R

R R R R R R R R R R

Cooling airF← Status Burner Ope.
Burner← Modified Burner Ope.

OutletShut down147

Ⅱ. Roller hearth kiln

Response of HAPOCO:
Finished(1) Increase kiln pressure to positive

Action : To be ±0 mmH20 at 1st burner by closing exhaust damper
Effect : Decrease to intrude cold air from outside into the kiln
Energy conservation

2 % (According to the actual results and experience)

Fuel ( LPG ) consumption : 328 ton / 2001year
Unit price of LPG : 6,000,000 vnd / ton
Energy consumption : 328 × 0.02 × 6,000,000 = 3,936 × 10 4 vnd / year
=2,500 us $ / year
(mmH 2 O)
0.3
0.2
0.1
0
- 0.1
- 0.2
- 0.3
- 0.4

Kiln pressure

Pressure

Temperature

(℃)
1000
800
600

Heat curve

400200Time (h)ExhaustWaste heatFF

Cooling air

F

Inlet

OutletBurner

15

Response of HAPOCO:
implemented(2) Introduce biscuit firing process

Action : No need to change firing condition ( heat curve, kiln pressure etc )of decoration firing , but should be increase pushing speed
Effect : Improve quality of ware ( to be smooth glazed surface , whiteness andtranslucency )but fuel ( LPG ) consumption increase much more than decoration firing

Response of HAPOCO:
implemented

Ⅲ. Shuttle kiln

(1) Install high speed type burner or introduce high speed type kiln
Effect : decrease temperature difference between top and bottom
shorten firing hour ( firing cycle )Energy conservation

1 % (According to the actual results and experience)

Fuel ( LPG ) consumption : 816 kg / batch for 2 kiln
Unit price of LPG : 6,000 vnd / kg
Energy consumption : 816 × 0.01 × 6,000 = 4.9 × 10 4 vnd / batch for 2 kiln
= 3 us $ / batch for 2 kiln

168

Fiber wall

Firing goods
Stack gas

Inlet ( door )( Kiln car )ChimneyHigh speed burner

179