Cambodian firms need decentralized wastewater treatment techs
chinagate.cn, March 23, 2015 Adjust font size:
Tongji University recently issued a survey report on Cambodian wastewater treatment technology demands, listed the needs for sewage treatment technology in Cambodia and discussed possible cooperation on wastewater treatment technology between Cambodia and China.
Phnom Penh, located on the banks of the Tonlé Sap and Mekong River, is the capital and largest city of Cambodia. It is the nation's center of economic and industrial activities, as well as the center of security, politics, cultural heritage, and diplomacy. Cambodia has a stable domestic politics and social economy, with an annual GDP growth rate of above 7%. However, as the economic activity and annual GDP of Phnom Penh continue to grow, so too has its sewage problem. The municipal infrastructure in Cambodia, even in its capital, has lagged behind its social development.
Industrial enterprises’ need for decentralized wastewater treatment technology and facilities
Cambodia has an industrial system centered on light industry, in which garment manufacturing occupies a large share. According to the Garment Manufacturers Association of Cambodia, there are 550 garment factories in Cambodia of which 60 are garment washing plants. Seventy percent of these factories are owned by Chinese investment companies.
After spinning, dyeing and garmenting, textile needs to be washed for decontamination, shrink-proofing and other special visual functions. This washing process produces fiber tow, dyes, pastes and chemical additives (detergent, softener etc.). Without treatment, discharge from the washing process will cause serious water pollution.
The Cambodian government is currently improving its environmental legislation and regulations to meet its social development objectives. It is therefore forcing enterprises to run primary wastewater treatment (Table1). The original simple water filtration device for the washing process cannot meet current water quality discharge standards. There is an urgent need to introduce advanced technology and equipment for washing wastewater treatment.
Table 1Effluent standard for pollution sources discharging wastewater to public water areas or sewer access
|
No |
Parameters（项目） |
Unit （单位） |
Allowable limits for pollutant substance discharging to（限值） |
|
|
Protected public water area |
Public water area and sewer |
|||
|
1 |
Temperature |
0C |
< 45 |
< 45 |
|
2 |
pH |
|
6 – 9 |
5 - 9 |
|
3 |
BOD5 ( 5 days at 200 C ) |
mg/l |
< 30 |
< 80 |
|
4 |
COD |
mg/l |
< 50 |
< 100 |
|
5 |
Total Suspended Solids |
mg/l |
< 50 |
< 80 |
|
6 |
Total Dissolved Solids |
mg/l |
< 1000 |
< 2000 |
|
7 |
Grease and Oil |
mg/l |
< 5.0 |
< 15 |
|
8 |
Detergents |
mg/l |
< 5.0 |
< 15 |
|
9 |
Phenols |
mg/l |
< 0.1 |
< 1.2 |
|
10 |
Nitrate (NO3 ) |
mg/l |
< 10 |
< 20 |
|
11 |
Chlorine ( free ) |
mg/l |
< 1.0 |
< 2.0 |
|
12 |
Chloride ( ion ) |
mg/l |
< 500 |
< 700 |
|
13 |
Sulphate ( as SO4 ) |
mg/l |
< 300 |
< 500 |
|
14 |
Sulphide ( as Sulphur ) |
mg/l |
< 0.2 |
< 1.0 |
|
15 |
Phosphate ( PO4 ) |
mg/l |
< 3.0 |
< 6.0 |
|
16 |
Cyanide ( CN ) |
mg/l |
< 0.2 |
< 1.5 |
|
17 |
Barium ( Ba ) |
mg/l |
< 4.0 |
< 7.0 |
|
18 |
Arsenic ( As ) |
mg/l |
< 0.10 |
< 1.0 |
|
19 |
Tin ( Sn ) |
mg/l |
< 2.0 |
< 8.0 |
|
20 |
Iron ( Fe ) |
mg/l |
< 1.0 |
< 20 |
|
21 |
Boron ( B ) |
mg/l |
< 1.0 |
< 5.0 |
|
22 |
Manganese ( Mn ) |
mg/l |
< 1.0 |
< 5.0 |
|
23 |
Cadmium ( Cd ) |
mg/l |
< 0.1 |
< 0.5 |
|
24 |
Chromium ( Cr )+3 |
mg/l |
< 0.2 |
< 1.0 |
|
25 |
Chromium ( Cr )+6 |
mg/l |
< 0.05 |
< 0.5 |
|
26 |
Copper ( Cu ) |
mg/l |
< 0.2 |
< 1.0 |
|
27 |
Lead ( Pb ) |
mg/l |
< 0.1 |
< 1.0 |
|
28 |
Mercury (Hg ) |
mg/l |
< 0.002 |
< 0.05 |
|
29 |
Nickel ( Ni ) |
mg/l |
< 0.2 |
< 1.0 |
|
30 |
Selenium ( Se ) |
mg/l |
< 0.05 |
< 0.5 |
|
31 |
Silver ( Ag ) |
mg/l |
< 0.1 |
< 0.5 |
|
32 |
Zinc ( Zn ) |
mg/l |
< 1.0 |
< 3.0 |
|
33 |
Molybdenum ( Mo ) |
mg/l |
< 0.1 |
< 1.0 |
|
34 |
Ammonia ( NH3 ) |
mg/l |
< 5.0 |
< 7.0 |
|
35 |
DO |
mg/l |
> 2.0 |
> 1.0 |
|
36 |
Polychlorinated Biphenyl |
mg/l |
< 0.003 |
< 0.003 |
|
37 |
Calcium |
mg/l |
< 150 |
< 200 |
|
38 |
Magnesium |
mg/l |
< 150 |
< 200 |
|
39 |
Carbon tetrachloride |
mg/l |
< 3 |
< 3 |
|
40 |
Hexachloro benzene |
mg/l |
< 2 |
< 2 |
|
41 |
DTT |
mg/l |
< 1.3 |
< 1.3 |
|
42 |
Endrin |
mg/l |
< 0.01 |
< 0.01 |
|
43 |
Dieldrin |
mg/l |
< 0.01 |
< 0.01 |
|
44 |
Aldrin |
mg/l |
< 0.01 |
< 0.01 |
|
45 |
Isodrin |
mg/l |
< 0.01 |
< 0.01 |
|
46 |
Perchloro ethylene |
mg/l |
< 2.5 |
< 2.5 |
|
47 |
Hexachloro butadiene |
mg/l |
< 3 |
< 3 |
|
48 |
Chloroform |
mg/l |
< 1 |
< 1 |
|
49 |
1,2 Dichloro ethylene |
mg/l |
< 2.5 |
< 2.5 |
|
50 |
Trichloro ethylene |
mg/l |
< 1 |
< 1 |
|
51 |
Trichloro benzene |
mg/l |
< 2 |
< 2 |
|
52 |
Hexaxhloro cyclohexene |
mg/l |
< 2 |
< 2 |
